GE jet engine bracket challenge

All aircraft engines require the use of efficient and cost effective brackets. Additive manufacturing creates opportunities to build unique and highly efficient bracket-like structures. Here is an opportunity to show your best design.

When designing critical components for aircraft engines, today’s designers are constantly challenged with the tradeoﬀ between performance requirements for strength and stiﬀness on one hand and size and weight on the other. Recently, software tools have been developed to aid designers in optimizing their part designs. However, today’s manufacturing methods restrict designers ability to take advantage of these optimized structures beyond a certain level of complexity. Additive manufacturing is lifting the constraints of traditional manufacturing processes, giving designers the ability to grow practically any shape, enabling the use of fully optimized lightweight designs that do not sacriﬁce performance.

Participants in this challenge will use additive manufacturing as the basis for optimizing an existing aircraft engine bracket.

The designs submitted will be analyzed and evaluated via simulation, and the top ten designs will be selected for fabrication and testing. These optimized engine bracket designs will be additively manufactured and subjected to a given loading scenario. The winning entries will best satisfy all of the performance criteria with the lowest mass.

The part

Loading brackets on jet engines play a very critical role: they must support the weight of the engine during handling without breaking or warping. The brackets may be used only periodically, but they stay on the engine at all times, including during flight. But these brackets aren’t the only parts on an engine that offer weight-reduction opportunities. There are many similar load-carrying parts on the engine that, because they were designed for conventional manufacturing technologies, are not fully optimized for both performance and weight. By substantiating Additive Manufacturing in this particular case, we will enable significant weight savings throughout the engine.

The test section

The designs entered in this competition that meet the weight and size envelope requirements will be evaluated by simulation for performance based on the load conditions given in Requirements Section below. The top ten designs will be manufactured using additive manufacturing and subjected to the defined load cases. To simulate engine transport and demonstrate maximum load carrying capacity, the part will be subjected to the individual load conditions shown in the Requirements Section below with the specified load being applied to 3/4” diameter pin at interface 1 while interfaces 2-5 are fixed. For designs that meet the performance criteria, the static loading will be increased to show ultimate capability. Designs that do not match the interface dimensions will be disqualified.

This Challenge will have TWO phases:

PHASE I:

Submit an improved design based on the provided diagram and specs from June 12 to August 9 (note: extended on July 19, 2013). These designs will be analyzed and evaluated via simulation with the top ten designs awarded $1,000 each.

PHASE II:

The top ten optimized engine bracket designs from Phase I will then be additively manufactured and subjected to a given loading scenario. The top 8 designs will receive awards from a total prize pool of $20,000. Phase II will run from September 17 to November 15 (note: dates changed after Phase I extension on July 19, 2013). The final announcement is set for mid-December.

Requirements

You can design your entry in any CAD software as long as STEP or IGES file is submitted.
The optimized geometry must fit within the original part envelope. STEP file will be available via the Download specifications button, soon.
Material: Ti-6Al-4V
Service Temperature: 75 F
Minimum material feature size (wall thickness): 0.050 in.
Interface 1: 0.75 inch diameter pin. The pin is to be considered infinitely stiff.
Interfaces 2 – 5: 0.375-24 AS3239-26 machine bolt. Nut face 0.405 in. max ID and 0.558 in. min OD. The bolts are to be considered infinitely stiff.
Load Conditions:
1. Max static linear load of 8,000 lbs vertical up.
2. Max static linear load of 8,500 lbs horizontal out.
3. Max static linear load of 9,500 lbs 42 degrees from vertical.
4. Max static torsional load of 5,000 lb-in horizontal at intersection of centerline of pin and midpoint between clevis arms.
Added based on Community questions (6/11/2013):
- Assume yield strength is 131 ksi.
- Participants should target the lightest weight designs.
Please post your mass or volume reduction compared to the original part envelope in your entry description. This will make it easier for the judges to sort the entries at the end of the Challenge. Thanks! (Added 06/14/2013)

Download specification

Rules

See Official Rules at http://blog.grabcad.com/ge-terms-of-service/ for details. Contest opens on June 11, 2013. Must submit at least one Entry by July 26, 2013 (extended to August 9, 2013) to be eligible for Phase II. Must be 18 years of age or older to participate. No purchase necessary. Void where prohibited.

THESE OFFICIAL RULES SUPERSEDE ANY OTHER RULES AND TERMS & CONDITIONS ON THE WEBSITE OF SPONSOR OR GRABCAD.
By registering for the competition, you accept the conditions stated in these official rules (http://blog.grabcad.com/ge-terms-of-service/), agree to be bound by the decisions of the judges and warrant that you are eligible to participate in the competition. If you do not accept all of these official rules, then please do not register for the competition. We recommend that you print a copy of these official rules for your future reference.
PHASE I – During Phase I, Entrants will create an improved aircraft engine bracket design using the design and specification information (“Design and Specs”) on the Competition Website. Entrants can use any CAD software to create the design but the Entry must be submitted as a STEP or IGES file.
PHASE II – The top ten (10) Entries from Phase I will be additively manufactured and subjected to the loading scenarios defined on the Competition Website. The top eight (8) Entries with the lowest mass which also satisfy all the testing performance criteria (defined herein and also set forth on the Competition website) will receive additional prize awards (described herein).
The PHASE I of this Challenge starts on June 11, 2013 and ends on August 9, 2013 (note: extended end of Phase I on July 19, 2013).
PHASE II will run from September 17 to November 15 (note: dates moved due to Phase I extension, above). Final announcement is separate from Phase II dates.
Judging - Entries in Phase I and II will be analyzed and evaluated by a panel of (5) five judges (the “Jury”) comprised of experts from GE and GrabCAD.
PHASE I -The Entries will be analyzed and evaluated via simulation based on the identified performance criteria set forth on the Competition Website. Judging for Phase I will occur during a two week period from August 9th to August 23rd (dates moved due to Phase I extension, above). The top ten (10) Entries that meet the performance will be selected as prize winners.
PHASE II – The top ten (10) Entries from Phase I will be additively manufactured and subjected to the defined load cases on the Competition Website. Entries also will be evaluated for suitability for production from an additive manufacturing perspective. Other considerations will include determining load at failure and long term durability. Judging for Phase II will occur during a three month period from September 17 to November 15 (note: dates moved due to Phase I extension). The top eight (8) Entries that satisfy all the performance criteria with the lowest mass will be selected as Phase II winners. Final announcement of Phase II winners is planned for mid-December.
Tag your entries with "generalelectric"

Prizes

: Phase I: $1,000 for each of the TOP 10 entries
Phase II: Additional awards for TOP 8 entries from a total prize pool of $20,000 as shown below.
PHASE I, 1-10th Prize: $1,000 cash each
PHASE II, 1st Prize: $7,000 cash
PHASE II, 2nd Prize: $5,000 cash
PHASE II, 3rd Prize: $3,000 cash
PHASE II, 4-8th Prize: $1,000 cash each

About the jury?

The Jury consists of judges who are experts from GE and GrabCAD.

About GE

GE works on things that matter. The best people
and the best technologies taking on the toughest
challenges. Finding solutions in energy, health
and home, transportation and finance. Building,
powering, moving and curing the world. Not just
imagining. Doing. GE works.

For more information, visit the company's website
at www.ge.com

410 comments

Paul Tripon over 11 years ago

wow, that's a more serious contest. Great news

Paul Tripon has uploaded 75 CAD models & has left 2039 comments.
Tomas over 11 years ago

:) very serious! :)

Tomas has uploaded 50 CAD models & has left 752 comments.
Sara Sigel over 11 years ago

Who's excited for this one? I know the GrabCAD Community will create some amazing solutions for GE!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Oncescu Ionut Cosmin over 11 years ago

Are multiple entries allowed ?

Oncescu Ionut Cosmin has uploaded 9 CAD models & has left 11 comments.
Juan Jose P. over 11 years ago

Could we have a step file of the original file or the exact dimensions?. What is the max weight of the part?

Juan Jose P. has uploaded 4 CAD models & has left 54 comments.
William over 11 years ago

Woooow this has to be one of the best challanges ever on GrabCAD this is a big major stepping stone and a challange of a life time, good luck to all that enter.

William has uploaded 112 CAD models & has left 6853 comments.
Gochat over 11 years ago

wow

Gochat has uploaded 47 CAD models & has left 31 comments.
Andrew Coyne over 11 years ago

What is the original part envelope size? Is there a model of the original bracket to use as a reference anywhere?

Andrew Coyne has uploaded 41 CAD models & has left 60 comments.
Andrew Coyne over 11 years ago

Is there any tag that need to be applied to the entry?

Andrew Coyne has uploaded 41 CAD models & has left 60 comments.
Matthew Stonebraker over 11 years ago

Great challenge! Even if I don't participate, I will be VERY interested in watching this one play out. Great job GrabCAD on working to help put together such an interesting and high-stakes contest, and great job GE on taking a risk with out-sourcing your design to the public like this. If this is successful, I hope to see more things like this in the future!

Matthew Stonebraker has uploaded 6 CAD models & has left 51 comments.
bj over 11 years ago

What are the relevant material properties for simulating the Additive manufactured Ti–6Al–4V you guys at GE have in mind? The yield stress might be different from "normal" solid Ti–6Al–4V?

bj has uploaded 75 CAD models & has left 128 comments.
Ping Du over 11 years ago

agree with Juan, we need the dimensions to place the bolt and pin. By the way, the load 3 seems 30 degrees from horizontal instead of verticav, from the figure.

Ping Du has uploaded 0 CAD models & has left 1 comments.
Farandy Angesti Liong over 11 years ago

What is the original part envelope dimension?

Farandy Angesti Liong has uploaded 23 CAD models & has left 26 comments.
Siddarth over 11 years ago

superb challenge...thanks GE--this might be an interesting test on PLM skills...

Siddarth has uploaded 72 CAD models & has left 100 comments.
Bart_1989 over 11 years ago

So lets get back to work!

Bart_1989 has uploaded 6 CAD models & has left 42 comments.
Sara Sigel over 11 years ago

@Oncescu.Ionut.Cosmin You can upload multiple entries.
@Andrew.Coyne I will confirm any necessary tags, which are usually added automatically during the "Submit your entry" process.

I will work on getting more detail on the technical questions asked. Great to see so much early interest. Keep the questions coming. We will update the Challenge requirements, as needed.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Arek K. over 11 years ago

Hi,
Does anybody tell me what is part envelope size ? Thank you.

Arek K. has uploaded 79 CAD models & has left 169 comments.
Juan Jose P. over 11 years ago

I agree with bj, What properties does the Additive manufactured Ti–6Al–4V have?

Juan Jose P. has uploaded 4 CAD models & has left 54 comments.
Sara Sigel over 11 years ago

If you have the same questions that were already asked, sit tight for some answers. No need to ask again, we are on top of it. If you think of something new, feel free to comment.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Fahad Rafi Butt over 11 years ago

Edison must be proud ;)

Fahad Rafi Butt has uploaded 360 CAD models & has left 643 comments.
Fahad Rafi Butt over 11 years ago

The optimized geometry must fit within the original part envelope. whats the size? this is serious stuff,, arbitrary dimensions is not an option :p

Fahad Rafi Butt has uploaded 360 CAD models & has left 643 comments.
Fateh MERRAD over 11 years ago

it is time to return to competitions on GrabCAD :))

Fateh MERRAD has uploaded 22 CAD models & has left 793 comments.
Ármin Fendrik over 11 years ago

Nice challenge. May I ask for dimensions in SI?

Ármin Fendrik has uploaded 49 CAD models & has left 105 comments.
Sara Sigel over 11 years ago

Two new requirements have been added based on your questions:
- Assume yield strength is 131 ksi.
- Participants should target the lightest weight designs.

The graphic wording has been fixed to say "30 degrees from Horizontal" in Load 3 and you should expect a STEP file of the original part soon.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Nemanja Ranković over 11 years ago

Another nice challenge :)

Nemanja Ranković has uploaded 114 CAD models & has left 479 comments.
Patrick Hughes over 11 years ago

Sara, a step file of the mating (male) part interface would also be important and appreciated. Thanks.

Patrick Hughes has uploaded 5 CAD models & has left 26 comments.
Sara Sigel over 11 years ago

Challenge update! Please see the corrected load conditions in the graphic and requirements section.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
hpero over 11 years ago

Congratulatiions to GE! This is true incentive.

hpero has uploaded 0 CAD models & has left 4 comments.
Giacomo Calzoni over 11 years ago

Isn't 131.000 psi too much as a yield strength?

Giacomo Calzoni has uploaded 15 CAD models & has left 12 comments.
Tom Martin over 11 years ago

In addition to yield strength, what is the factor of safety requirements?

Tom Martin has uploaded 60 CAD models & has left 109 comments.
Sara Sigel over 11 years ago

The STEP file is now available via the "Download specifications" button.
@Giacomo.Calzoni The requirements lists a yield strength of 131 ksi.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

Thanks Sara.We will definitely give our best.
I hope that we can utilise our analysing skills also by this competition through GC.

Great Engineering Challenge .... !!!! Thanks to GE and GC.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
EDISON PHOENIX over 11 years ago

@Sara Is it 42 degree or 30 degree in the loading condition 3 ?

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
EDISON PHOENIX over 11 years ago

Sorry i can get that it would be 42 degree from the update.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Hubert Baumgartner over 11 years ago

Folks i have a hint for you: If you hit the DOWNLOAD SPECIFICATION button a textfile opens. Save this as "name.step" and you have got the geometry!

Think this is the first task of the challenge :-)

Hubert Baumgartner has uploaded 6 CAD models & has left 31 comments.
Hubert Baumgartner over 11 years ago

Question for GE: My INVENTOR gives me a total mass of 4,524lb for the original part, is that true?

Hubert Baumgartner has uploaded 6 CAD models & has left 31 comments.
Simonr over 11 years ago

This looks like a good challenge!

The spec says the additive part must fit within the same part envelope. Does Interface 1 have to be constructed as a clevis with a space between the two side walls. Do you have a part file for the structure which is mated to Interface 1 by the pin?

Weight saving is certainly possible without this, but by changing the shape of the clevis, it may be possible to improve the stress distribution in the base for the given force vectors and thus reduce the weight further.

Thanks for posting such an interesting challenge!

Simonr has uploaded 24 CAD models & has left 214 comments.
Ben Campbell over 11 years ago

Check the T's and C's people
"Prize Winners: By accepting a prize award for your Phase I Entry, you agree to assign to GE all aspects and content of your Entry, including the intellectual property rights in and to your Entry and all intellectual property that it may contain or embody, including but not limited to all rights to any copyrights, design rights, and inventions (whether or not patentable). PRIZE WINNERS WILL BE REQUIRED TO EXECUTE AN ASSIGNMENT OF RIGHTS IN ORDER TO CLAIM THE PRIZEv"

Ben Campbell has uploaded 0 CAD models & has left 3 comments.
Simonr over 11 years ago

A couple more questions.
In the description, you reference Horizontal, Vertical and Z-Axis, could you on your diagram show the x,y,z axis + what you consider Horizontal and Vertical. The diagram shows the part in a different orientation to the STEP file - and there is no guarantee that when imported into a different CAD system that the Axis labels are the same!
You have specified max static loads plus a dynamic load in one axis. Should these be considered to be the yield point, or is there a 'safety factor' that needs to be applied on top of this?

Simonr has uploaded 24 CAD models & has left 214 comments.
bj over 11 years ago

Load condition 3 is 42 degrees from vertical, but the illustration suggests a much greater angle, also Im not too sure about load condition 4. Im curious about the references of the loads and contraints that will be used in the evaluation of the designs. Any chance of a screenshot of this instead of the illustrations?

bj has uploaded 75 CAD models & has left 128 comments.
monika over 11 years ago

Real Engineering application.

monika has uploaded 1 CAD models & has left 12 comments.
Michael Barjaktarevic over 11 years ago

Now this is an awesome design challenge.. Goes to show how cloud based/ Web based establishments like GRABCAD have infinite potential through collective knowledge in all spheres of engineering! Big corporates should use this facility far more!

Michael Barjaktarevic has uploaded 0 CAD models & has left 1 comments.
Fahad Rafi Butt over 11 years ago

horrible step file, seriously, who made it?

Fahad Rafi Butt has uploaded 360 CAD models & has left 643 comments.
ali over 11 years ago

Excellent ...

ali has uploaded 7 CAD models & has left 47 comments.
Sara Sigel over 11 years ago

@Edison 42 degrees is the updated angle.

I will get more clarification on the load conditions and get back to you all. Apologies for the necessary trick when downloading the STEP file. This may be different from browser to browser. Any browsers out there downloading the spec with no trouble? Recommend it to your fellow participants, please :)

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Kevin Koch over 11 years ago

How many significant figures do we have to be accurate to? Some dimensions in the step file seem not to truncate.

Kevin Koch has uploaded 1 CAD models & has left 3 comments.
Bar Danino over 11 years ago

In chrome it's a simple .stp download... No text stuff to worry about

Bar Danino has uploaded 7 CAD models & has left 33 comments.
Bart_1989 over 11 years ago

No problems with Firefox as well.

Bart_1989 has uploaded 6 CAD models & has left 42 comments.
Kevin Koch over 11 years ago

@bj it seems like the 4th condition is the twisting of the mounting pin in the bracket, in a plane parallel to the base.

Kevin Koch has uploaded 1 CAD models & has left 3 comments.
bj over 11 years ago

Doesnt the object that causes the bolt to twist in the 4th condition, also contact the walls of the clevis arms which will influence the twisting? I would really like to see references of the loads and contraints that will be used by GE to evaluate the designs.

bj has uploaded 75 CAD models & has left 128 comments.
Thierry over 11 years ago

Hello everybody,
Really very interesting this chalenge! Has some work there!
Here is my first question: could you confirm the standard (norme) of Ti6Al4V? (ASTM F136 and ISO 5832-3 or other?)

Thierry has uploaded 11 CAD models & has left 23 comments.
Lorenzo Temporin over 11 years ago

hello,I can not download the specifications...

Lorenzo Temporin has uploaded 33 CAD models & has left 19 comments.
Sara Sigel over 11 years ago

@Lorenzo Try downloading using Firefox or Chrome and email me at sara@grabcad.com if you still have issues. Thanks!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Martti over 11 years ago

Poisson ratio, modulus of elasticity and density.
What about deformation?

Are the TOP 10 of phase I evaluated solely by minimum weight?
"For Entries that meet the performance criteria, the static loading will be increased to show ultimate capability."

Does there have to be a safety factor? Or is stress with a value of 130,9 ksi acceptable?

"I would really like to see references of the loads and contraints that will be used by GE to evaluate the designs." +1

Martti has uploaded 2 CAD models & has left 5 comments.
Martti over 11 years ago

Is the bracket at an angle to every main plane in the specification file?

Martti has uploaded 2 CAD models & has left 5 comments.
Lorenzo Temporin over 11 years ago

Thanks Sara, i did the download...

Lorenzo Temporin has uploaded 33 CAD models & has left 19 comments.
Wellington over 11 years ago

Where can I get the model?

Wellington has uploaded 2 CAD models & has left 2 comments.
Farzin Raafat over 11 years ago

What is the saftey factor number for the designing and analysis?(Safety factor=S yeild/S max)(S:tension)

Farzin Raafat has uploaded 23 CAD models & has left 134 comments.
Sara Sigel over 11 years ago

@Wellington You can get the model from the "Download specifications" button under the Requirements section. If you have any issues, try Firefox or Chrome. Good luck!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

Everyone, I should hear back on today's questions soon. Look for an update here!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Farzin Raafat over 11 years ago

waiting for saftey factor number sara.

Farzin Raafat has uploaded 23 CAD models & has left 134 comments.
Yingcong Chou over 11 years ago

Haven't seen the safety factor, do we just use the yield strength to simulate?

Yingcong Chou has uploaded 1 CAD models & has left 1 comments.
James over 11 years ago

Hello GE!

Good to see you guys pushing the envelope of 3D printing as well as helping to evolve crowd sourcing! Just one suggestion, shouldn’t we have the clearance specifications for the omega link or other possibly specialized lifting hardware that will be used with this?

All the best,
James

James has uploaded 0 CAD models & has left 5 comments.
Bart_1989 over 11 years ago

I have question to all guys with uploaded their brackets, have you manage to make stress analysis already? If so, you are bloody fastv

Bart_1989 has uploaded 6 CAD models & has left 42 comments.
Awp Harsh over 11 years ago

agreed... http://grabcad.com/badzes-1 . I am also wondering how fast they are submitting. I am still analysing their [.STEP] model.

Awp Harsh has uploaded 39 CAD models & has left 82 comments.
Simonr over 11 years ago

I have a feeling they are taking the requirements literally, that the first round is only looking for a weight saving and that the next round will select the strongest. If that's true, you might as well enter a shell at the minimum wall thickness - and not worry whether it will actually do the job.
At the moment there is not enough information to do any real analysis of the part - but maybe that was intentional, and they really are just looking for the lightest possible bracket?

Simonr has uploaded 24 CAD models & has left 214 comments.
Sara Sigel over 11 years ago

Updates from the GE Aviation team:
- There should be no dynamic load condition. I am removing the statement in the requirements section that states “Max dynamic load of 6G vertical(Z)” and “Engine weight carried by bracket: 4500 lbs”.
- The team will work on a better illustration but this is a good description, "the 4th condition is the twisting of the mounting pin in the bracket, in a plane parallel to the base."
- There is not a standard for additively manufactured Ti 6-4. Assume the physical properties are similar to AMS4911.
- There is no part file for the structure which is mated to Interface 1 by the pin. Assume the pin is infinitely stiff per the requirements.
- Interface 1 has to be constructed as a clevis with a space between the two side walls, but perhaps for future challenges they could open this up to design improvements.
- Axis labels are not important. Base your design on the loading conditions diagram which specifies the direction of the loads.
- Due to differences in CAD software, they will allow deviations up to 0.010” outside of the original part envelope.
- Jared says you can blame the "bracket at an angle to every main plane in the specification file" on him. It isn’t critical to the design, but he apologizes because he's sure it drives you guys crazy. :)

GREAT questions and participation so far, keep it up GrabCADrs!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

Overall comment from comments and questions so far from the judges to help you all get started: "Regarding the safety factor, this is up to the contestants to evaluate based on the geometry they create. There are other factors we will consider such as suitability for additive manufacturing. Certain geometric features may lend themselves to being more or less robust from an additive manufacturing standpoint, and could have an impact on mechanical properties. It wouldn’t be fair to force everyone into the “worst-case” safety factor. We are looking for out of the box ideas."

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Bar Danino over 11 years ago

to everyone struggling with the angle: rotate the part 48.5 degrees clockwize when looking from the right.

Bar Danino has uploaded 7 CAD models & has left 33 comments.
Simonr over 11 years ago

I've run a bit of analysis on the original part - and it looks like the pin (not included in original) will fail before the part itself - even if made from pure Unobtanium!

It might be reasonable to assume that a new part which will withstand the supplied forces, already has the necessary safety factor 'built in'?

Simonr has uploaded 24 CAD models & has left 214 comments.
Tomek F. over 11 years ago

Are Private entries will be accepted
There is no reference in this challenge.?

Tomek F. has uploaded 224 CAD models & has left 160 comments.
Stephen Nyberg over 11 years ago

Is DMLS the method used to manufacture?

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Sara Sigel over 11 years ago

Thanks @Bar.Danino! Look for an update on the new questions soon.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Jorge Reyes over 11 years ago

How do we avoid someone to download our entry and modified it just a little and then use that design ( our design ! )??? Should all the entries be public ????

Jorge Reyes has uploaded 0 CAD models & has left 3 comments.
Stephen Nyberg over 11 years ago

@jorge, you could always just wait and upload your design at the end.

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Stephen Nyberg over 11 years ago

I am re-creating the original part to have the demnsions to work with. I noticed that I think interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches. Is this correct?

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Danny Tasmakis over 11 years ago

Hi there GC and GE first of all great challenge! something every one can sink their teeth into at the same time lose some hair :)
Just one question in regards to the angles on the top face of the bracket how important are they does anything interface with them or are they just clearance?
Thanks.

Danny Tasmakis has uploaded 55 CAD models & has left 652 comments.
Awp Harsh over 11 years ago

Stephen Nyberg , re-creating this model from the original step will be the best either modifying the original.step. my step conversation is li'l differs from you.. Interference 3 is 0.41 inches while interferance 2, 4 & 5 are 0.42 inches. it is changing every model lolzz.!! :P We are going to model this on different values. analysis results will definately change for the same model.

Awp Harsh has uploaded 39 CAD models & has left 82 comments.
Lorenzo Temporin over 11 years ago

are there also combinations of loads?

Lorenzo Temporin has uploaded 33 CAD models & has left 19 comments.
Pit over 11 years ago

finally a challenge for mechanical engineers!! nice!!

Pit has uploaded 24 CAD models & has left 106 comments.
Mészáros Márió over 11 years ago

The forces and torques operate together, or separately. Must have all of them at the same time?

Mészáros Márió has uploaded 9 CAD models & has left 31 comments.
Bar Danino over 11 years ago

each is a seperate test as far as I can tell

Bar Danino has uploaded 7 CAD models & has left 33 comments.
Mészáros Márió over 11 years ago

Thank you Bar Danino ;)

Mészáros Márió has uploaded 9 CAD models & has left 31 comments.
Sara Sigel over 11 years ago

@Tomek.F Private entries will not be considered. You can read this in the terms and rules for this Challenge via the links provided, above.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

Update from the GE team on your questions:

- Clearance specifications: The inner diameter of the bracket clevis at the pin interface in the original part envelope is 0.7525”, therefore the diametral clearance needs to be 0.0025” to the 0.75” pin.
- Will the pin hold under these load conditions? Do not worry, the pin will not fail at the specified loads.
- Please note that I will be adding a new request from the GE Team to the requirements. Please post your mass or volume reduction compared to the original part envelope in your entry description. This will make it easier for the judges to sort the entries at the end of the Challenge. Thanks!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tomek F. over 11 years ago

thank you @sara.sigel

Tomek F. has uploaded 224 CAD models & has left 160 comments.
Ahmed A.Elbahgy over 11 years ago

I think the judjments can go throgh privet project enven I do not add them
is that right ??

Ahmed A.Elbahgy has uploaded 48 CAD models & has left 22 comments.
Ioannis Skarlatakis over 11 years ago

Hi Sara I don't want to be a pain... for your IT guys, but, do you think that it would be a good idea for the system to recognize the public / private projects and accordingly to allow or not the submission???? Just an idea ... to avoid any misunderstandings!!!

Cheers!

P.S.

Really great job for the particular challenge!!!

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
AIT OUFKIR YASSINE over 11 years ago

That's a Great challenge i will do all my best,

AIT OUFKIR YASSINE has uploaded 32 CAD models & has left 377 comments.
Romulo Medeiros over 11 years ago

Ótimo desafio.

Romulo Medeiros has uploaded 9 CAD models & has left 3 comments.
Pit over 11 years ago

@ Sara Sigel:
It is assumed that this challenge must find the 10 best designs. All engineers should have the same input data, if not, it will be impossible to properly assess these designs. Can you please ask GE which is the safety factor for this bracket? Thanks in advance.

Pit has uploaded 24 CAD models & has left 106 comments.
naveen thontepu over 11 years ago

@ Sara
i am working on the original model so i am not changing the relative positions of the holes and the pin. But can we change the the width of the base and other dimensions of the model or does GE wants some dimensions constant other than the position of the nuts and bolts????
Thanks

naveen thontepu has uploaded 55 CAD models & has left 147 comments.
Sara Sigel over 11 years ago

@Ahmed.EL-Bhje No private projects will be considered. Please upload PUBLIC.
@Ioannis.Skarlatakis Great idea!
@Alejandro.Rodriguez What data are you referring to?
@Pit Please see notes from GE above... "Regarding the safety factor, this is up to the contestants to evaluate based on the geometry they create. There are other factors we will consider such as suitability for additive manufacturing. Certain geometric features may lend themselves to being more or less robust from an additive manufacturing standpoint, and could have an impact on mechanical properties. It wouldn’t be fair to force everyone into the “worst-case” safety factor. We are looking for out of the box ideas."

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

Also, I'm sending along questions so look for another update from GE.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Ahmed A.Elbahgy over 11 years ago

I will re upload it thanks

Ahmed A.Elbahgy has uploaded 48 CAD models & has left 22 comments.
Andrew over 11 years ago

GE, I assume the additive technique will be DMLM. Will you consider bracket designs with trapped hollow volumes? If so, are designers required to apply the tap density of the Ti 6-4 powder to the trapped volumes to accuratly calculate mass?

Andrew has uploaded 0 CAD models & has left 1 comments.
EDISON PHOENIX over 11 years ago

@Sara I want to work with my friends for this challenge.I feel better with workbench projects(Private entries) for sharing ideas and files.When we will finish, we can share our work to public.Is it acceptable or not?

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
EDISON PHOENIX over 11 years ago

@GE to reduce the von mises stress in my design.I have to use lenghty bolts.If there is any restrictions for using the depth of the holes in INTERFACES 2 & 5 ..?

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Mészáros Márió over 11 years ago

Somebody can send to me this machine bolt 0.375-24 AS3239-26 ?
I can't find it :S v

Mészáros Márió has uploaded 9 CAD models & has left 31 comments.
Sara Sigel over 11 years ago

@Edison.Phoenix That is fine. Just make sure you switch it to public before the deadline. Good luck!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

Thank you Sara.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Julius Siador over 11 years ago

@Sara or GE, as I understand, "the optimized geometry must fit within the original part envelope" means there is no mass/volume sticking out from that boundary. So, will an entry be totally disqualified or can still be considered if its geometry sticks out in areas that is considerable in actual part service? Or do we need to comply to that requirement regardless of the resulting further weight reduction?

Julius Siador has uploaded 16 CAD models & has left 62 comments.
Flaviano Crespi over 11 years ago

Very interesting challenge,
to obtain the maximum reduction in size is necessary to evaluate every small detail, I think you should therefore provide sizes of the mandatory interface 1, ie the pin that mates with the two ears on which the loads are applied, especially the diameter and the length of the two parts on the side of the ears.
In fact, the size of these ears can be significantly reduced as a function of the limits of the interface 1.
Also on the model provided, between the two ears there is a space formed by milling which extends throughout the length of attack of the ears. I suppose that in this compartment is housed the eyelet of a tie rod which is coupled with the pin. This discharge must be maintained or can be reduced? or which diameter has the mating eyelet?

Flaviano Crespi has uploaded 345 CAD models & has left 1632 comments.
White Orca Designs over 11 years ago

Are these brackets only used during removal/insatll of the engine? If so would it not make sense to have them installed before removal of the engine, and then removed after install? I ask because I was an aircraft mechanic in the army, and installing lifting brackets is not a difficult task at all.

White Orca Designs has uploaded 1 CAD models & has left 2 comments.
Pit over 11 years ago

Bolt, Machine - Double Hexagon Extended Washer Head, Pd Shank, Nickel Alloy, Uns N07718, 185 Ksi Min, .3750-24 UNJF-3a

Pit has uploaded 24 CAD models & has left 106 comments.
JEFF ROOT over 11 years ago

Sara, can you give any details on the additive manufacturing process that will be used to build? Will this go on a powder bed or LENS machine? I ask because there are significant design considerationsddepending on the AM process.

JEFF ROOT has uploaded 0 CAD models & has left 1 comments.
Stephen Nyberg over 11 years ago

Here is something that may be of interest to all here:
http://www.youtube.com/watch?v=l0SXlkrmzyw&feature=youtu.be

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Ardo Rand over 11 years ago

@Sara.
How the brackets will be manufactured - entirely machined or first molded and then machined (interfaces 1 to 5)?

Ardo Rand has uploaded 14 CAD models & has left 75 comments.
Pit over 11 years ago

I've done some considerations for simplification... I think the result is ok.
Obviously, it can be optimized... I'll do later.
I hope you like it
Thanx

Pit has uploaded 24 CAD models & has left 106 comments.
Noe Lima over 11 years ago

se algunas cosas pero le intentare y lo lograre

Noe Lima has uploaded 5 CAD models & has left 3 comments.
Igor Lins e Silva over 11 years ago

@Sara: Do you have any information on the displacement tolerance upon full loading?

Igor Lins e Silva has uploaded 58 CAD models & has left 91 comments.
Siddarth over 11 years ago

Sara, I am having one doubt
Whether it is compulsory to use the specified bolt
or we can use the modified bolt design
because in my design, i used alternative counter bore hole
and i am getting considerable stress
when i change the bolt hole dimension given there
it may increase the stress and deformation
please assist me........

Siddarth has uploaded 72 CAD models & has left 100 comments.
Ron Woodward over 11 years ago

Does The additive manufacturing process allow the construction of hollow sections?
If so do all hollow sections require vent holes?
If so What is the minimum diameter of a vent hole?

Ron Woodward has uploaded 0 CAD models & has left 2 comments.
Sara Sigel over 11 years ago

Updates from GE:
1) DMLS is the method used to manufacture.

2) Interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches... That is correct, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.

3) The load conditions should be applied separately.

4). The base dimensions can be modified as long as the resulting geometry does not excehowever we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

@Andrew, does the new information from GE answer your question?
@Julius.Siador See #2 and #4 above. Does this help clarify?
@Stephen.Nyberg Thanks for sharing that Additive MFG video from GE!

With respect to interface 1 and the pin, I'll reiterate what was earlier heard from the aviation team, "There is no part file for the structure which is mated to Interface 1 by the pin. Assume the pin is infinitely stiff per the requirements. Interface 1 has to be constructed as a clevis with a space between the two side walls, but perhaps for future challenges they could open this up to design improvements."

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
ali over 11 years ago

It just need Topology Optimization .... by writing a macro for ansys or doing with solidworks .... Big fun for me as ME bachelor student ;)

ali has uploaded 7 CAD models & has left 47 comments.
straxico over 11 years ago

yeah

straxico has uploaded 2 CAD models & has left 2 comments.
Andrei over 11 years ago

Hello,
Is there another way to download the original STEP model.
I can't open the link Download Specification.

Andrei has uploaded 2 CAD models & has left 4 comments.
Javier Sanchez over 11 years ago

Hello,
I'm also having problems trying to open the "Downloaded Specification" icon.

Javier Sanchez has uploaded 0 CAD models & has left 1 comments.
Andrei over 11 years ago

Javier, I guess you're using Internet Explorer. Try with Google Chrome or Mozilla Firefox.

Andrei has uploaded 2 CAD models & has left 4 comments.
Bart_1989 over 11 years ago

Try to use firefox, or chrome browser.

Bart_1989 has uploaded 6 CAD models & has left 42 comments.
Sara Sigel over 11 years ago

Thanks @Andrei and @Badzes, you beat me to it!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Siddarth over 11 years ago

@sara, is there any fixed height for interface 2-5?? based on the height only the thickness of the bracket base is to be judged........please assist me......

Siddarth has uploaded 72 CAD models & has left 100 comments.
daniel zientara over 11 years ago

Can the mating part (or a portion of the mating part) that this bracket mounts to on the engine be posted?

daniel zientara has uploaded 20 CAD models & has left 26 comments.
Jorge Reyes over 11 years ago

One question guys, for the simulation, wich surfaces do you take as fixed? Cause ive been doing the simulation fixing the inner surface of the smaller holes in the interfaces 2-5 but that way even in the original model I get zones below safety factor of 1. Software im using is solidworks simulation. Can someone tell me wich features/surfaces must be fixed ? or maybe upload a pic? Thanks

Jorge Reyes has uploaded 0 CAD models & has left 3 comments.
Abhilash Markkassery over 11 years ago

@Sara
"Updates from GE:
1) DMLS is the method used to manufacture.
2) Interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches... That is correct, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.
3) The load conditions should be applied separately.
4). The base dimensions can be modified as long as the resulting geometry does not excehowever we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination."
#4 is not very clear. Can you please restate it, so as to make it clear.

Abhilash Markkassery has uploaded 2 CAD models & has left 1 comments.
4DID over 11 years ago

Is IGES/STP a must? I work with additive manufacturing for a while, specialized in porous structures, and always use .STL files. I could force the generation of a STP file but it would not be recognized in traditional CAD software as a solid. More a collection of lots and lots of triangular shaped surfaces. Any suggestions??

4DID has uploaded 0 CAD models & has left 1 comments.
Martin Dirker over 11 years ago

@il canario, I'm sure the STP/IGS requirement is to enable analysis for Phase 1.

Martin Dirker has uploaded 5 CAD models & has left 26 comments.
Igor Lins e Silva over 11 years ago

@il canario, that's not exactly true, iges/step is the better way to transfer high precision geometry between cad packages without the losses of stl formats

Igor Lins e Silva has uploaded 58 CAD models & has left 91 comments.
Prithviraj P Shetty over 11 years ago

@ il canario, igs/stp is the standard cad format, so that it can be opened in almost all cad softwares

Prithviraj P Shetty has uploaded 18 CAD models & has left 50 comments.
Stephen Nyberg over 11 years ago

Why are so many people making desings to be manufavutred in traditional methods or commenting on designs stating they would be hard to machine? The new bracket is going to be 3D printed GE want ideas outside the box and not traditional.

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Marty007 over 11 years ago

@Stephen. I think that the machined designs are relatively quick to put together and analyse. There are still about 35 days left in the contest, so I think you'll see the more creative solutions in the coming weeks. (I'm working on one...)

Marty007 has uploaded 1 CAD models & has left 10 comments.
Charlie Pyott over 11 years ago

Hey, thanks to GE for this challenge and to Sara for fielding all of these questions!
I had a few more to add to the pile:

1) Deflection: Are there any specifications, ballpark numbers or general design priorities for maximum deflection of the pin? I have simulations from the original model showing .25mm pin movement but with could see this getting pretty out of hand with a volume optimized design (theoretical pin deflection under load at 8.0mm+ before failure etc.)

2) Pin Attachment: I understand that the pin is infinitely stiff but the diagram seems to indicate that it is secured in place via some caps on either end. Should the “pin” be considered a type of bolt/nut or an infinitely long rod with no caps? This makes a huge difference in designing the part in how much the body has to resist the clevis arms from splaying under load.

3) Finally, the submissions are going to get more and more similar the closer this gets to the end of Phase 1 because there is an optimal solution to this problem. I really hope I am wrong on this one but this is a competition with rewards and it seems like this has the potential to go pretty bad in a “you stole my design!!” kind of way with public models being available. Are there any recommendations on this?

Charlie Pyott has uploaded 2 CAD models & has left 5 comments.
teigan over 11 years ago

it's rather naive to be assuming that simulation is going to reveal the strongest brackets. i'd bet successful designs will get left behind in the first phase, while faulty designs will fool simulation. i suggest you make a provision to withold awarding any prizes on simulation alone. otherwise, we'll all just design to beat simulation, as opposed to designing to make a useful real part.

teigan has uploaded 9 CAD models & has left 167 comments.
Jorge Reyes over 11 years ago

I agree with @charlie pyott about the " you stole my design" I've already seen 2 or 3 designs pretty similar to mine, still, im still a little bit confused about the surfaces thar must be fixed for the simulation, I disagree with @teigan cause a well done simulation should be pretty similar to the reality. (sorry for the english, im from m exico)

Jorge Reyes has uploaded 0 CAD models & has left 3 comments.
Siddarth over 11 years ago

i agree with Teigan, Mass reduction only doesn't judge the perfect design. Also the simulation results will tell the perfect design.....

Siddarth has uploaded 72 CAD models & has left 100 comments.
teigan over 11 years ago

a "well done" simulation is not necessarily "similar to reality", and usually isn't. in fact, simulation is less reliable than calculaions done manually using force vectors and tedious math on paper. newly graduated engineers will spend weeks setting up a simulation that in the end is useless to their employers. the world is doomed.

teigan has uploaded 9 CAD models & has left 167 comments.
James Sylphide over 11 years ago

A question to the Judges & Jury: The brief states the all four loads are static and linear. Are we to assume that all four of these loads occur simultaneously at Time (t) = x ? Cheers James

James Sylphide has uploaded 5 CAD models & has left 105 comments.
Amin Kashef over 11 years ago

@James,
The load conditions should be applied separately.

Updates from GE:
1) DMLS is the method used to manufacture.
2) Interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches... That is correct, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.
3) The load conditions should be applied separately.
4). The base dimensions can be modified as long as the resulting geometry does not excehowever we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.

I restate it for who are new

Amin Kashef has uploaded 20 CAD models & has left 28 comments.
Amin Kashef over 11 years ago

@Sara
It seems that who are recently join the challenge won't see the updates that are in the comments!
for everyone to notice the updates It's better to put them under the requirement column. Just a suggestion.

Amin Kashef has uploaded 20 CAD models & has left 28 comments.
Abhijith over 11 years ago

Hi everyone i am a first yr mech student can someone tell me the function of the engine brackets ??

Abhijith has uploaded 14 CAD models & has left 10 comments.
Tim Titus over 11 years ago

I have read the comments and don't see anyone asking this:

Will our designs be considered more highly if they absolutely MUST be manufactured via DMLS (3d printing), or will those that could also be made through traditional means be equally evaluated.

Looking at the submissions, only a few designs are not possible through traditional means, and It would be a shame to not consider them equally regardless of how they should be manufactured. After all, for a part that will be made in quantities of more than just a few, traditional methods are much more economical.

Thanks!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
James Sylphide over 11 years ago

@Amin
Mate! If one force is applied as per the current brief, there will always be other forces along other vectors. In order to optimise the model these - resultant - forces must be considered in the design.

James Sylphide has uploaded 5 CAD models & has left 105 comments.
Andrew Coyne over 11 years ago

I have a query regarding the requirement for our newly designed parts to be within the part envelope, could I have this clarified, My thinking is it could be one of two scenarios. i.e
1 - Envelope = Overall bounding box around the entire model, overall x,y,z dimensions,
or
2 - Envelope = must be with in the exact faces of the original GE bracket design.
Which of these is correct?
(Apologies if I have missed an answer to this already).

Andrew Coyne has uploaded 41 CAD models & has left 60 comments.
Tim Titus over 11 years ago

Not a bad question Andrew, I assume you want to build up material between the two eyelets? I am also curious about this.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Julius Siador over 11 years ago

That's what I was asking all about a week ago, Andrew. I hope that will be clarified sooner by GE.

Julius Siador has uploaded 16 CAD models & has left 62 comments.
Ravichandra J P over 11 years ago

Any restrictions on support structures?

Ravichandra J P has uploaded 43 CAD models & has left 72 comments.
Sara Sigel over 11 years ago

Excuse me for the enormous comment, but I have some responses for your questions and will follow-up with another comment about questions I'll ask the GE team
.....................
@Siddarth This is some guidance from the above requirements and comments: Interfaces 2 – 5: 0.375-24 AS3239-26 machine bolt. Nut face 0.405 in. max ID and 0.558 in. min OD. The bolts are to be considered infinitely stiff. Clearance specifications: The inner diameter of the bracket clevis at the pin interface in the original part envelope is 0.7525”, therefore the diametral clearance needs to be 0.0025” to the 0.75” pin. Interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches... That is correct, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination. The base dimensions can be modified as long as the resulting geometry does not exceed current envelope, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination.
.............................................................................
@Daniel.Zientara We do not have the mating part to post. See this comment, "There is no part file for the structure which is mated to Interface 1 by the pin. Assume the pin is infinitely stiff per the requirements. Interface 1 has to be constructed as a clevis with a space between the two side walls, but perhaps for future challenges they could open this up to design improvements.
........................................................................"
@il.canario STEP or IGS formats are required for entry.

.............................................................................@Marty007 and @Stephen.Nyberg I like the creativity!

.............................................................................@Teigan The idea is to have simulation vet ideas but the GE Aviation Team will be there to also consider innovative solutions above more traditional. See this comment, "There are other factors we will consider such as suitability for additive manufacturing. Certain geometric features may lend themselves to being more or less robust from an additive manufacturing standpoint, and could have an impact on mechanical properties. It wouldn’t be fair to force everyone into the “worst-case” safety factor. We are looking for out of the box ideas."

.............................................................................
Thanks @Amin.Kashef for helping @James.Sylphide! Good idea on adding important comments to the requirements. I can add some details there.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

@Charlie.Pyott See the existing notes on the pin, above. I'll see if I can get more details on the style (bolt/nut or rod/cap).
@Tim.Titus I will seek guidance for you on this, thanks.
@Andrew.Coyne, @Tim.Titus and @Julius.Siador I will get an answer on whether it is scenario 1 or 2. @Ravichandra.JP I think you're question will be answered by this as well.

..........................

Thank you for staying inquisitive GrabCADrs! We will get you answers soon.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
teigan over 11 years ago

thanks for your response albeit straying from the original point i was making.

and will your simulations be limited to rigid body finite element statics?

teigan has uploaded 9 CAD models & has left 167 comments.
UyenNhi Tr over 11 years ago

Thank you Sara for all clarifications

UyenNhi Tr has uploaded 0 CAD models & has left 1 comments.
Siddarth over 11 years ago

Thank you sara............

Siddarth has uploaded 72 CAD models & has left 100 comments.
Tim Titus over 11 years ago

Cheers Sara!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Tan Wei Kok over 11 years ago

@Andrew Nice suggestion :p

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
Hubert Baumgartner over 11 years ago

@Andrew: Workshob brackets are not critical for flight operations :-)
@ Sara+GE: As asked bevor, is a deformation under load of more than 5mm (0,2inch) possible. Titanium has a horrible Youngs modulus like rubber.

Hubert Baumgartner has uploaded 6 CAD models & has left 31 comments.
max over 11 years ago

Hi guys and Gals I'm not an engineer so its likely I watch this one competition from the sidelines, but has anyone considered "Generative modelling" like Grasshopper to create bone like structure.

Something like this:
http://www.grasshopper3d.com/photo/cactus-skeleton-4?context=latest
http://www.grasshopper3d.com/photo/hexaring?context=latest

Architects use it all the time, and it seems it would lend itself nicely to 3D printing and for strength to weight ratio.

But then again I'm not an engineer.

max has uploaded 6 CAD models & has left 13 comments.
Lumas over 11 years ago

I've been waiting excitedly for some surfacing magician to come up with a concept involving this kind of modelling, Max. I'd have no idea how to even start on it...!

Lumas has uploaded 16 CAD models & has left 66 comments.
Tan Wei Kok over 11 years ago

@Max I think some of the engineers start off with that approach but probably draw back by one of the design requirements: Minimum material feature size (wall thickness): 0.050 in.

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
EDISON PHOENIX over 11 years ago

We have designed one model with 480 grams(77.6 % mass reduction) having max von mises stress 116 ksi. Check our entry and give your suggestions.We(Elemental Design Team) are awaiting for your feedbacks.

Elemental Design (beta version)

Elemental Design Team.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
max over 11 years ago

@Luke Maselkowski yes im looking forward to this too! It might be the Holey grail.
@Tan Wei Kok I think wall thickness may not be an issue... sorry, this can be set as a parameter with one of these generative modelling programs. The problem maybe a firm understanding of the generative modelling program itself is needed to get a good and controlled (not random) result for engineering.

max has uploaded 6 CAD models & has left 13 comments.
Sara Sigel over 11 years ago

Updates for the group from the GE Aviation Team!

------------------------------------------------------------------

Q: Should the “mated pin” be considered a type of bolt/nut or an infinitely long rod with no caps?
A: Consider the pin an infinitely long rod.

------------------------------------------------------------------
Q: Will designs be considered more attractive if they MUST be manufactured via DMLS, or will those that COULD be made through traditional means be equally evaluated?
A: The focus is on additive manufacturing. However, if the lightest designs could be made through conventional manufacturing methods, there is no penalty for that.

------------------------------------------------------------------
Q: What do you define as the "envelope?" 1 - Envelope = Overall bounding box around the entire model, overall x,y,z dimensions, or 2 - Envelope = must be with in the exact faces of the original GE bracket design. Which of these is correct?

A: #2. Designs must be with the exact faces of the original GE bracket design. Please see the Rules and Requirements for details.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

Thanks Sara for your clarification about the "Envelope".

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Tim Titus over 11 years ago

Cheers!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Tim Titus over 11 years ago

For all AUTODESK INVENTOR users:

The material library properties of Ti-6Al-4V are WRONG! I have corrected this and created a new custom material library for you to then run FEA tests with the correct material specs. You can get the file from the downloads sections of my model:

THE KRAKEN BRACKET

Good luck!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Igor Lins e Silva over 11 years ago

Excelent Tim!

Igor Lins e Silva has uploaded 58 CAD models & has left 91 comments.
Wilson Wong over 11 years ago

Hi Sara, just to clarify. From the pics and step, it seems like, interface 2 should be 0.42" and interface, 3-5 (or actually 4, 5, 5 as shown on the pic) should be 0.406". As you said, the range is 0.406" to 0.42", so it doesn't really matter but I would just like to clarify it. Thanks.

Wilson Wong has uploaded 2 CAD models & has left 4 comments.
Tim Titus over 11 years ago

Hi Sara,

I see this being asked by many users...

Can you please ask GE what parts should be constrained (fixed and unmoveable) for the FEA test?

IE, which of these surfaces should be fixed:
1. Where the bottom of the bolt head meets the top face of the part?
2. The shaft of the holes?
3. The bottom where the part meets the surface it connects to?
4. Also, If we are using the machine bolt for the test as in the guide, should we constrain the bolt to the part (not fixed), and then fix constrain the bolt?

I see many people using many different methods for the FEA tests, and I myself am getting huge differences in results depending on where I constrain or fix the various surfaces. Knowing how GE will do the test, and what software they will use would be a HUGE help to all of us to ensure our designs will pass before submitting them.

Thanks again for your help Sara!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Sara Sigel over 11 years ago

I'll ask @Tim.Titus, thanks for bringing this to my attention.
@Wilson.Wong "Interface 3 is 0.42 inches and interface 2, 4, and 5 are 0.406 inches, however we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination."

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Wilson Wong over 11 years ago

Hi Sara, sorry I think I might not have explain it well. I was just trying to point out that the downloaded step model, the label of the interfaces in the picture you provided above, and the information you given from reply to comment do not match, so was wondering it will be good to maybe rectify it. But it's not critical. Thanks.

Wilson Wong has uploaded 2 CAD models & has left 4 comments.
dinesh reddy over 11 years ago

Hi i am trying to upload my model in this competation but its is redirecting to the mail library after uploading the file i am not able to see my entry in this GE challenge can any help me out

dinesh reddy has uploaded 9 CAD models & has left 7 comments.
Potat over 11 years ago

@ Sara
Would it be possible to clarify whether there is any requirement for this bracket to be aerodynamic (i.e. is it an appendage or is it covered during flight) and if so what is the forward direction. Thanks in advance.

Potat has uploaded 1 CAD models & has left 1 comments.
teigan over 11 years ago

in the scheme of things, any weight savings on these little brackets are insignifigant. so is any aerodynamics. you all have no sense of perspective. what is it like to go through life so clueless about your surroundings?

teigan has uploaded 9 CAD models & has left 167 comments.
Tim Titus over 11 years ago

If there were a dislike button, I would use it for the last comment. This is a community of designers, engineers, and people that enjoy freeing their imagination to design in the best way possible. Thinking about all the aspects of a design, no matter how insignificant they may seem, is part of that process to invent something new and brilliant. No need to be rude to other members for their curiousity and enthusias.m

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Lumas over 11 years ago

Hey Guys. I'm not really sure if this is the right place to put this, but maybe others are suffering from similar problems. I haven't had much experience with FEA, so appologies if these are really basic questions...
So I've been working on stress testing some of my models, and I'm getting some unexpected results: Firstly, I'm seeing much higher stresses when leaving corners unfilleted. I think I'm right in assuming a sharp edge would have a higher stress concentration, right? What's going on! Secondly, I'm getting super high stresses just around the base of the bolt holes. Could this be to do with how I'm contraining the model (fixing the shaft surface of the bolt hole), or is it really just a poorly designed part?
Any answers would be really appreciated :)

Lumas has uploaded 16 CAD models & has left 66 comments.
Andrew Smolkov over 11 years ago

@Luke.Maselkowski
Hey, Luke! I am surprised these results, like you.
I think that the reason lies in the fact that we don't take into
consideration the real constraints in the simulation, which could be in a real environment.
For example, the lower surface of the bracket... Where it should be based?
Perhaps this is a big solid surface. Perhaps this is a small patch or four tubercles.
We don't know anything about it.
So we need to be based on the requirements that provided us with the competition.
The second. The simulator is not perfect, it allows you to estimate a model rough,
only to find the main trends in solutions of the task.
This is my opinion, maybe you'll agree with me.
Good luck!

Andrew Smolkov has uploaded 38 CAD models & has left 384 comments.
Ioannis Skarlatakis over 11 years ago

@Luke Maselkowski & @Andrew Smolkov
..
Hi guys I would like to say some words based on what Luke & Andrew posted above as it seems quite right.
..
The sharp edges in FEA are source of singular stresses (very high stresses that tend to infinity)... To explain this briefly is an issue of the Mesh as the area where the nodes lie is almost zero... so you are expected to distinguish the magnitude of the expected stresses while you can hide the high stresses by rescaling your measure - bar. The fillet command will also relax this problem of singularities but you have to make sure that you use a good structure of mesh in the curvy face. However this procedure might take a bit more as the mesh in the fillet is more complex but yes this is a good solution.
So on a way Luke you are right about the concentration!!!

Regarding the constraints this may be the harder task of all...To be honest there are many different combination that can bring the same solution. On the other hand a small alteration it might change everything... This is a good reason why you need experimental data or some valid results to compare with the ones from your simulation.
..
What you have already mentioned is considerable so this is what I suggest...
..
Lets assume that your part lies on x,y axis and z represent the high...
..
So,let's decompose the constraints of the bolts... constraints can be selected to avoid movement in x,y axis by picking the internal face of the holes I think this is quite obvious :P...
Regarding the z axis the step-in face (looking from top) of the hole needs to be selected and fixed (alternatively prescribed displacement can be used to allow for some DOF) as the bolt it suppose to press down that face.
I am sure you are aware that as long as we use bolts and not rivets we are not expecting high shear stresses... so with the above constraints we trying to give a freedom for the model to bend (I hope that makes sense to you)...
..
Based on Andrew's post I think it would be nice to have an idea where this bracket sits. Then you can put some additional consideration of a friction factor through the contact of the bottom surface & the base to see any influences in your results. But I think it can be neglected depends on the surface that sits on.. (It's up to you)
..
Andrew mentioned that a simulation is not perfect... well I say that is right!!!
The thing is that the quality of the simulation sometimes doesn't come directly.
That means though the assumption that you make and the tolerances that you give, you might get an approximation with an error of 5 - 2 % and that is next to ideal solution.
Additionally, I bet that Andrew would know, that analytical procedures are exist for various problems to predict the exact solution.

So in my personal opinion you have to make sure that you used all the potentials that your simulation allows for and then you can "accuse" ;P your software that you can not have a better approximation...

Just remember that even the bad results are good results that will take you away from a WRONG conclusion!!!

Best Regards Guys

IOANNIS

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
Siddarth over 11 years ago

@loannis you are exactly right...........my point of view is @andrew told that the simulator is not perfect and you told that the approximation error we have to consider is 5-2%..........and I think we can reduce this approximation error by increasing the mesh quality at the important edges and surfaces
Perhaps this clearly shows the exact stress distribution on the stress concentrated areas. Mesh refinement is the another way to reduce the approximation error......

Siddarth has uploaded 72 CAD models & has left 100 comments.
Lumas over 11 years ago

@Loannis, what an amazing answer, thanks for putting all the time into that.
Actually I made a mistake in my original comment, in the first point I meant to say that I was seeing higher stresses when filleting corners, which is what I found strange. After a bit of testing though, and this seems to fit in with what's been said, I think this has to do with mesh quality. The filleting of the corners forces a finer mesh which in turn produces a more accurate result. When leaving corners unfilleted, the stresses increase pretty dramatically as the mesh quality is improved. Please correct me if I'm wrong :)
Again, thanks guys. Can't wait to get back to testing!

Lumas has uploaded 16 CAD models & has left 66 comments.
Tim Titus over 11 years ago

@luke @loannis & @Andrew, I asked Sara above what testing GE will be using as I am encountering exactly the same issues you all are, including the high stress points on the bolts that then distract from other places that might actually be REAL stress points. I hope Sara gives us some clarification on this matter and tells us what software they will be using. After that, we should be able to at least match the testing environment of GE, which is the important thing, not whether the FEA results actually hold truth for the real world.

Something that I don't think you have mentioned is that the face where the bolts press down on may not be the same surface area as the original model. Some people have flattened that face down into a bigger surface area. Of course fix constraining that surface would then cause adverse results to the tests as the entire surface would not receive the same pressure as directly under the bolt head. I think in this case it is necessary to make a new face by projecting the geometry of the bolt head on the larger face and fix constraining that. Am I right about this?

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Sara Sigel over 11 years ago

Great discussion going! Glad to see others helping out with FEA tips. I will get back to you with more details but the holiday weekend will delay it a bit.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Arfi'an over 11 years ago

I am agree with Ioannis. I think a detail confirmation from GE of their original part analysis and the environment scenario would help us a lot since so far, a lot of participant is only guessing the environment scenario, especially the constrain. As far I know, in a FEA study, a constrain has an important rule for the software to determine the stress concentration result (the reason already explained by Ioannis).
...
However, while waiting for the GE confirmation, I think the good way is whatever assumption you take, just do the analysis based on those assumption in your model and the original model to compare it. With that way, you will find the exact difference between your model and the original model as a based of your optimization.
...
This method above is only my personal opinion, and all the participant doing a great job so far.

Good Luck Guys...

Arfi'an has uploaded 6 CAD models & has left 21 comments.
Lumas over 11 years ago

@Tim. Good point on the bolt head constraint. In SolidWorks I guess the method here would be to project a split-line onto that surface in the shape of the bolt head...
But as Loannis mentioned, if you're constraining the X and Z direction (shaft surface) to only allow vertical movement, and the Y direction (bolt head and ground surface) to allow only lateral movement (slider constraints, I think?); will this prevent this issue?

Lumas has uploaded 16 CAD models & has left 66 comments.
Scott Frash over 11 years ago

Great Competition! questions for GE:

Could you please clarify the envelope specification? From the comments i gather that the specification is this: the new part must reside inside an envelope defined by a space .01" larger in all directions from the faces of the file "original.stp" - true or false?

What geometry defines the interfaces 2-5? do we need to keep the counterbores in order to not be disqualified? Based on the hole sizes and the specs on the bolts, it appears that the bolt holding force is via friction only - below the nut face, no normal loading on the sides of the head or threads. Is there another reason for the counterbore and is it a constraint to keep it?

Scott Frash has uploaded 2 CAD models & has left 10 comments.
Tim Titus over 11 years ago

@Scott, The envelope has been well covered by Sara already above: I've copied it below. I would say that the counterbores are mandatory based on this info.

Q: What do you define as the "envelope?" 1 - Envelope = Overall bounding box around the entire model, overall x,y,z dimensions, or 2 - Envelope = must be with in the exact faces of the original GE bracket design. Which of these is correct?

A: #2. Designs must be with the exact faces of the original GE bracket design. Please see the Rules and Requirements for details.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Tim Titus over 11 years ago

@Scott, I hope the above helps but perhaps you should talk in more detail about what you are trying to accomplish by eliminating them... I assume you would like to extend the bolt holes and shafts upward to add more strength, however it is possible to due away with the counterbores all together if you simply extrude the top surface all the way down to the level of the top of the bolt holes. The first (raising the bolt hole / shafts) would technically disqualify you, while the second (extruding downward) would not.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Scott Frash over 11 years ago

I was just wondering what surfaces define the "interface" that we must keep. Is it only the surface below the nut face, or do we have to also keep the entire diameter surface of the counterbore.

Scott Frash has uploaded 2 CAD models & has left 10 comments.
Siddarth over 11 years ago

@scott the same question from my side too......whether we have to keep the counter bore like in original.stp,
second doubt...if the counter bore hole is to be maintained, whether the bolt head faces have to be constrained in all directions or we have to give only bolt penetration there
another question to everyone.....as per earlier description the bracket is to be kept permenantly with the engine and so for that whether we have to consider the bracket as a pre-stress body or not???

Siddarth has uploaded 72 CAD models & has left 100 comments.
EDISON PHOENIX over 11 years ago

@GE, From the above discussion, i can understand one thing.Most of us having different perspectives about the constrains.Please fix this immediately.I am using one constrain condition:Interfaces 2-5 are fixed.I have designed one model with 580grams with very good results with the above condition.

Another doubts:
1.The hole depth in interfaces 2-5 is .309 inches in the original model.Definitely we have to keep the depth or not?If we increase the depth the results will be too good.

2.@All,Can you please describe the constrains that you are using for your simulation.

Thanks in advance for your help.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Pit over 11 years ago

http://www.asminternational.org/static/Static%20Files/IP/Magazine/AMP/V171/I03/amp17103p19.pdf?authtoken=869a996b44fe329f3e88c4a9b40cd20c34febde1

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

hey guys, take a look to this document... very interesting... the FOS in the study was 10. I'm right with my assumptions for the study... ;)

Pit has uploaded 24 CAD models & has left 106 comments.
MASA over 11 years ago

need an engineering design to recreate the bracket

MASA has uploaded 76 CAD models & has left 38 comments.
Sara Sigel over 11 years ago

@Pit Your link only goes to the home page and does not show a particular document.
@Edison.Phoenix I will get you more information on the constraints for testing. Also, we will accept any nominal hole dimension at interfaces 2-5 between .406" to .420", in any combination

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Pit over 11 years ago

ok Sara, I'll upload it right now...

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

http://grabcad.com/library/frog-2/files/amp17103p19.pdf

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

amazing document!! posibly , this is what GE wants... is it possible?

Pit has uploaded 24 CAD models & has left 106 comments.
MASA over 11 years ago

@sara i need an engineering drawing if possible to re create the bracket

MASA has uploaded 76 CAD models & has left 38 comments.
Tim Titus over 11 years ago

Actually, a DWG sketch would be nice to have...

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Joseph Mayer over 11 years ago

Is it just me or is there a lack of basic information? Not only did I have to convert the provided file but I cannot subtract anything from it. Is there more specific data i.e. demensions that I am not seeing?

Joseph Mayer has uploaded 7 CAD models & has left 1 comments.
Tim Titus over 11 years ago

@Joseph. The file is a basic STEP file so that we can open it in any program. It therefore does not have any creation history to add or remove from. However, you can simply create planes and extrude (cut) away any material and once you have the basic starting shape you want (which is probably the top U frame and the 4 holes), then you can start building a new design from that. Doing it that way also ensures that the part will fit within the envelop for the holes.

As far as a lack of information, Sara has been really great in providing us everything we need, and I believe the only thing left to answer is how to setup constraints for the FEA tests (which she will be answering as soon as she can).

Tim Titus has uploaded 14 CAD models & has left 316 comments.
teigan over 11 years ago

small modern jet engines weight over 8000 kg. even if you could reduce the mass of your brackets by 99.9%, it would add no measurable improvement in performance or efficiency of an aircraft. that would have been immediately obvious to anyone competent. all other discussion taking place are pointless. why is low mass the main judging criteria of your challenge?

teigan has uploaded 9 CAD models & has left 167 comments.
Sara Sigel over 11 years ago

This challenge is all about exploring innovative new manufacturing methods. As we say in the brief, "All aircraft engines require the use of efficient and cost effective brackets. Additive manufacturing creates opportunities to build unique and highly efficient bracket-like structures."

Please keep in mind that the jury will also be considering, "...Suitability for additive manufacturing. Certain geometric features may lend themselves to being more or less robust from an additive manufacturing standpoint, and could have an impact on mechanical properties. We are looking for out of the box ideas."

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
teigan over 11 years ago

and that is a long winded nonsequiter response to a simple question, which in the end avoids answering the question.

teigan has uploaded 9 CAD models & has left 167 comments.
Ioannis Skarlatakis over 11 years ago

There is no reason, speaking generally (not only to teigan), to be rude and especially to people that do their best to assist all the rest of us. Please do not spam this long chat as integrate a lot of useful info for everybody.
In addition it would be nice to think twice before we post random comments this is not facebook!!!
Any engineer that agree or disagree with my above comment he can send me a private message PLEASE don't start a conversation that has nothing to contribute to this cool challenge.

P.S.
Fundamental engineering wants the weight as the most significant parameter among any design criteria especially in massive construction as in aerospace (Ti or Al, instead of Steel or Composite materials are few examples of alternative solutions in cases that you cannot modify your geometry).
Who ever wants more info he can just pick a University. 4 to 6 years are more than enough to convince anybody regarding this topic.

Best Regards to all & particularly to teigan

ioannis

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
teigan over 11 years ago

another unnecessarily long response that avoids addressing the very simple, and on 100% on-topic, real issue.

teigan has uploaded 9 CAD models & has left 167 comments.
Sara Sigel over 11 years ago

Let's keep things on topic - let me know if you have any concerns outside of the FEA test details which we'll have soon.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Siddarth over 11 years ago

18 days for deadline.......when will we come to know abt the details regarding FEA
As all of us know, it is impossible to design an optimized bracket without analyzing....
Still on date engineers are using different constraints for analyzing...as there was no final talks abt it till now.....
Waiting for your valuable talk Sara........
Thanks in advance

Siddarth has uploaded 72 CAD models & has left 100 comments.
Scott Frash over 11 years ago

@sara about the counterbore, is it a requirement to keep it in our model? Or does the interface only include the surface that actually sees a force (under the bolt head)... I am just not sure what the requirement is and what is meant by "interface"... I see that many of the contest submissions excluded the counterbore which may mean they are disqualified already? Could you please clarify the faces that must be kept?

Scott Frash has uploaded 2 CAD models & has left 10 comments.
Ravichandra J P over 11 years ago

According to previous updates, "Assume the physical properties are similar to AMS4911."
Is it fine if these values are used? or are there any other values to be used for material properties?
Density: 4420 kg/m^3
Young's modulous: 110Gpa
Tensile strength: 1000Mpa
and as per the challenge specification, yield strength: 131ksi
Got these values from http://www.aerospacemetals.com/titanium-ti-6al-4v-ams-4911.html
Poisson's ratio: .31
I am using solidworks.
Let me know if these values need to be taken differently.

Ravichandra J P has uploaded 43 CAD models & has left 72 comments.
Sara Sigel over 11 years ago

Let's keep this comment thread for specific questions about your submission. If you're inspired by the idea of additive manufacturing, please start a Q&A thread to discuss it further. Feel free to post a link to it here.

----------------------------------------

For this reason, I have removed any off-topic or general questions after my initial request to keep things focused. I apologize for the inconvenience. I think this will prevent any GrabCADrs questions from going unanswered. For those who are waiting on an update from GE, I will get answers to you as soon as I get them. @Damic I lost your comment accidentally. Would you mind reposting?

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Ravichandra J P over 11 years ago

Is it necessary to use pin for loading scenario? or if its fine to use the faces of eyelets for loading?
And can somebody provide a pictorial representation of case 4 loading?

Ravichandra J P has uploaded 43 CAD models & has left 72 comments.
Tim Titus over 11 years ago

@Ravichandra Jp.
Yes, it is necessary as you will get completely different results unless you apply forces from the clevis pin. I use Inventor 2014 and apply a "Moment" load on the pin and then define the direction and angle of torsion. It may be called something different depending on the software you are using. If you are using Solidworks SimulationXpress, you will not be able to do the proper FEA testing as simulation within assembly mode is not a feature unless you upgrade to Simulation Pro. This means you cannot apply forces from the clevis pin.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Nick Hampton over 11 years ago

Is the download spec link broken?

Nick Hampton has uploaded 20 CAD models & has left 26 comments.
Tim Titus over 11 years ago

@Nick. It still works for me...

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Nick Hampton over 11 years ago

@Tim. Thank god for that! :)

Nick Hampton has uploaded 20 CAD models & has left 26 comments.
Rohit Kumar Singh over 11 years ago

Can someone explain the asymmetrical design of the bracket.

Rohit Kumar Singh has uploaded 5 CAD models & has left 18 comments.
Rohit Kumar Singh over 11 years ago

And if someone has performed analysis on the original bracket, please share the FOS numbers on different load conditions..

Rohit Kumar Singh has uploaded 5 CAD models & has left 18 comments.
Tim Titus over 11 years ago

Original Part FEA analysis . I am not sure what you mean by "explain the asymmetrical design" but if you download the part and cut away until you have the base holes alone, you can utilize those while building your new design.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Tim Titus over 11 years ago

FOR ANYONE WHO HAS USED THE "I WISH THIS PAGE..." BUTTON!!

You are in the contacts list of Rosemary Astheimer from GRABCAD technical support. I just got a phishing scam email directing me to a fake Google Docs. I only trusted it as it was from Grabcad and I had sent something the day before, but DON'T INPUT YOUR EMAIL AND PASSWORD on the docs page!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Rohit Kumar Singh over 11 years ago

Thanks Tim for the analysis data.

Rohit Kumar Singh has uploaded 5 CAD models & has left 18 comments.
Rohit Kumar Singh over 11 years ago

@Sara..... There are no Comments/Feedback from engineers of GE and Grabcad on entries. It would be a lot helpful if engineers from GE reviewed entries and gave some comments on it before the deadline so that further improvements can be made.

Rohit Kumar Singh has uploaded 5 CAD models & has left 18 comments.
Tim Titus over 11 years ago

Just a heads up, but I noticed that exporting the file into STEP or IGES sometimes produces cracks in the mesh. I am not sure if this will affect the 3d print process, but it is something to check in the GRABCAD 3d viewer none the less. I also noticed that it happens more with STEP files than with IGES.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Marin Duplančić over 11 years ago

One question I haven't seen in the comments: how will the jury model boundary conditions? Ok, we have the infinitely long pin for the load, but what about the supports, do you consider the part resting on some surface or do you support it entirely via the bolt hole faces (upper face, lower face and cylindrical face)? Thanx

Marin Duplančić has uploaded 0 CAD models & has left 2 comments.
Ioannis Skarlatakis over 11 years ago

This link seems to have some familiar pictures ;P

http://www.mmsonline.com/articles/why-is-additive-manufacturing-important

However, my point is that I found accidently this site & it seems to have interesting info to share... enjoy!!!

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
Tim Titus over 11 years ago

@Marin,
I have already asked about the boundary conditions (fixed constraints) and Sara is awaiting an answer from the GE engineers. That being said, after have done extensive testing myself, I am not sure there is a perfect method for testing as depending on the design it seems that some constraints are more accurate than others. However, if they have a standard testing method, it will help us to at least have a base line to all match our designs to.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Yuvaraj over 11 years ago

hi,
the model is not symmetry about its centre plane.Asymmetry is intentional (because of loading condition) or the product is symmetrical about centre plane???

Yuvaraj has uploaded 1 CAD models & has left 3 comments.
andreas anedda over 11 years ago

Any news about the FEA?

andreas anedda has uploaded 5 CAD models & has left 26 comments.
AC-M over 11 years ago

Hello,
Please can you confirm that the loads (lbs) applied are inclusive of gravity? i.e. please clarify the units are lbf (pound-force) not lbm (pound-mass)
Many thanks!

AC-M has uploaded 0 CAD models & has left 2 comments.
richard kilshaw over 11 years ago

So what is everybody doing for a safety factor? It is my understanding that general lifting equipment requires a 1:4 design factor. These brackets are used to hoist the engine up right? So does anyone know what GE mandates as a design factor on their engine brackets?

richard kilshaw has uploaded 2 CAD models & has left 5 comments.
simon over 11 years ago

just wondering is it just me or is there anyone else having problems with the fillets around the bolt holes if they are unfilleted the stress is fine but if a fillet is put in even a small one the stress rises to about 4 to 5 times what it was. just tested a design where the stress on the bolt head area was 84ksi retested it with a 0.01 inch fillet and the stress went up to 418ksi and it showed the rest of the model with basically no stress. this surely cant be right

simon has uploaded 19 CAD models & has left 81 comments.
Tim Titus over 11 years ago

That's exactly the reason I have been also testing FEA with fixed constraints on the fillets themselves. Otherwise, the stress all accumulates there. Not the most accurate, but either is what is happening in the test to start with.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
simon over 11 years ago

@tim just been in looking at your bracket and the tests you were doing (nice job by the way) ive tested mine by just fixing the bolt head area no where else ive seen some entries where the bolt hole and bottom of the bracket are fixed surely this cant be right because if it is a 300 gram bracket is possible. with the fixings on the bolt head area im struggling to get under 430 grams with the new design. with the fact that there is only a couple of days left in the competition this really needs to be clarified by ge.

simon has uploaded 19 CAD models & has left 81 comments.
Eduardo Romo over 11 years ago

Hey guys I'm having trouble finding the way to set up the Load Condition 4 on SolidWorks Simulation, any heads up or tips on how's the best way to do it?

Eduardo Romo has uploaded 2 CAD models & has left 12 comments.
Eduardo Romo over 11 years ago

Nervermind guys I got it right just now. Cheers and good luck with the challenge!

Eduardo Romo has uploaded 2 CAD models & has left 12 comments.
Andrew Smolkov over 11 years ago

@eduardo romo
I think the answer lies directly in the task for this load: 5000 pounds per inch! It is necessary to build the pin in the centre of lugs and apply two forces opposite in direction to each other and same value, to pin's consoles. Place of application of forces should be 1 inch from the imaginary center of pin. And the value of the force should be 2500 pounds. Summary moment of force will be 5000 pound per inch. The plane of force application also is known from the task - it is the horizon. This is my opinion, maybe someone refute it? Good luck!

Andrew Smolkov has uploaded 38 CAD models & has left 384 comments.
Pit over 11 years ago

Made and analised in Catia v5.

The study is finished...!!

The Model No. 31 has a weight of 478g (1.0538lb).

I chose a safety factor of 8 (FOS = 8). The reason for this value is the following consideration:

Usually, in the calculation of support elements for the aerospace industry, the safety factor is around 4, but this is considering the manufacturing system (which is the material removal machining), this system allows directionality fibers of the material and your choice to get an element that behaves better mechanically. In the case of additive fabrication, there is no directionality of these fibers (as do not actually exist), and the mechanical behavior of the material is the same in all directions.

In order to correct this lack of directionality, I decided to double the safety factor.

Initial wight 2048gr
478g on my model#31, it means 1.0538lb, so 76.66% weight reduction.

Tension values are:
Cond#1: Maximun 8.74E8 N/m2 what means 126.76ksi
Cond#2: Maximun 8.99E8 N/m2 what means 130.39ksi
Cond#3: Maximun 6.60E8 N/m2 what means 95.72ksi
Cond#4: Maximun 6.53E8 N/m2 what means 94.71ksi

Pit has uploaded 24 CAD models & has left 106 comments.
simon over 11 years ago

quick question whats the story with the minimum thickness of 0.050 inches does that apply only to wall thickness or does it apply to the features and surface edges for example.

simon has uploaded 19 CAD models & has left 81 comments.
Sara Sigel over 11 years ago

We know that you all need more information on tests and that is coming soon. Due to the delayed response and in an effort to allow everyone to make their entries the best they can be we will be extending the deadline for Phase I to August 9th at 11:59pm UTC. You should see this reflected in the countdown, design brief, and rules sections.
------------------------
This means you will have more time to optimize your designs! News coming soon, stay tuned!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Amartesh Sehgal over 11 years ago

Hello Sara,

What is GE actually looking for in the entries for the first phase of the challenge. Lightest weight designs only that are pleasing to eyes or lightest weight designs with a high factor of safety? I am asking this because I have seen entries with mass as low as 100-125 gm and failing all the FEA tests even with a coarse quality mesh. Is optimization the second phase of the competition only? Does it mean we can submit ultralight entries for the first phase which do not pass FEA tests at all?

In the problem description, at one place it is mentioned to write mass reduction/volume reduction you have done on the original bracket. So does that mean GE will just select entries for first phase based solely on mass reduction with no consideration on low factor of safety of such designs and in doing so not even considering other entries with considerable mass savings and a good factor of safety still with a potential for further optimization?

Please clarify.

Regards,
Amartesh.

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Sara Sigel over 11 years ago

@Amartesh, good question. GE will be looking for mass/volume reduction. All entries selected will also have to pass the given load conditions (see the diagrams and notes in requirements). If someone has made significant reductions but their bracket doesn't not handle the loads, they will not be selected. I hope this helps! I will have more information on test constraints soon.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tim Titus over 11 years ago

If you are going to upload an entry to the contest, it's best to make sure that your design meets the requirements IE: the part "MUST fit within the size envelope/faces of the original part." A large proportion of the entries already submitted will be disqualified based on this rule alone.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
EDISON PHOENIX over 11 years ago

Finally we present our final design for all of your review.

Elemental Design

All the results are obtained by the 0.08 inch fine mesh (very accurate result) simulation using solidworks.I hope you will like our work.Your feedbacks and comments are most welcome.And also don't forget to give your rating out of five stars(*****) for our entry.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Manolo Valenzuela over 11 years ago

There are no reason to fix the fillets inside the c-bore as a constraints, unless you have a rounded bottom face bolts matching with the fillets 8 )

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Sara Sigel over 11 years ago

@Tim.Titus You're right. All basic requirements like load conditions and envelope constraints must be met before you can be in the running for mass/volume reduction. All participants please keep this in mind!
@Edison.Phoenix Thanks for releasing it for review!
@Manolo.Valenzuela Thank you for sharing your insight - we'll have more details from GE soon on this topic.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

@Sara, Thank you for your consideration.If we get the feedbacks from GE team it will be great to modify all of our designs before deadline.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Tim Titus over 11 years ago

@Manolo Valenzuela. I was constraining the fillets to obtain more accurate FEA test results before, however I now realize the best thing to do is simply remove all counter-bore fillets. I suggest all user apply this to their designs both in their testing, and when uploading the STP/IGES file for review. This will eliminate the problems users, including myself, were having when running FEA tests and seeing the stress concentrated on the fillets and thus causing high max KSI and failing the tests.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Siddarth over 11 years ago

Please see our Elemental Design Team second entry.....
Elemental Design #2
Comments are welcome....
I attached the Detailed documentation and individual reports regarding boundary conditions and loadings.....
http://grabcad.com/library/elemental-design-2-1/files/Full%20Report.pdf

Siddarth has uploaded 72 CAD models & has left 100 comments.
EDISON PHOENIX over 11 years ago

http://grabcad.com/questions/how-many-of-you-like-to-see-the-rating-system-for-our-models-in-our-gc

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Amartesh Sehgal over 11 years ago

@ Sara, Many thanks for the clarification!

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Eduardo Romo over 11 years ago

Guys I´ve submitted my entry, hope you can review it. Any feedback would be very helpful! GE Jet Engine Bracket - Proto 1

Eduardo Romo has uploaded 2 CAD models & has left 12 comments.
Amartesh Sehgal over 11 years ago

Hello Sara, I have another question for you... While selecting top 10 entries for phase one, will GE give equal weightage to suitability for additive manufacturing, ultimate load an entry can take and weight saving? Or will it be a three stage process i.e. an entry will first be evaluated for its suitability to additive manufacturing, shortlisted entries from first stage are tested for ultimate load and then in the third stage mass reduction is seen.

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Amartesh Sehgal over 11 years ago

@ Pit, What do you mean when you say that you chose a factor of safety 8. Is FOS not Yield Strength/ Maximum stress. From the stress values you have posted here, it doesn't seems that your model has a FOS of 8. Please clarify. Thanks!

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Gochat over 11 years ago

How much is 5000 lb-in to newton meters ??

Gochat has uploaded 47 CAD models & has left 31 comments.
Marin Duplančić over 11 years ago

565

Marin Duplančić has uploaded 0 CAD models & has left 2 comments.
Ryan Zehr over 11 years ago

http://www.wolframalpha.com/input/?i=How%20much%20is%205000%20lb-in%20to%20newton%20meters&t=crmtb01

564.9 N m (newton meters)

Ryan Zehr has uploaded 1 CAD models & has left 13 comments.
Gochat over 11 years ago

thank you @Ryan Zehr and @Marin Duplančić

Gochat has uploaded 47 CAD models & has left 31 comments.
pav_lechev over 11 years ago

Hello!
Obviously the most optimum geometry in the shape of a shell.
Too many projects meet this form.
I wonder how it will be determined the winner, as they are so similar.
I could not think of anything more original, so I will not participate :)
Success!

pav_lechev has uploaded 25 CAD models & has left 26 comments.
Ross Gilsenan over 11 years ago

Does anyone have an image showing how they applied load condition 4?

Ross Gilsenan has uploaded 3 CAD models & has left 3 comments.
Ryan Zehr over 11 years ago

It is a 5000 in-lb Moment acting through the center of the pin.

Ryan Zehr has uploaded 1 CAD models & has left 13 comments.
Arno Gramsma over 11 years ago

Dear Sara, is it allowed to use less bolt connections (still meeting load case requirements)

Arno Gramsma has uploaded 1 CAD models & has left 14 comments.
Lumas over 11 years ago

Quick question... Will the bracket be placed on a flat plane that extends the full way across the base of it? I.e. will the complete footprint of the bracket be in cotact with whatever it's sitting on?
In a lot of my simulations - especially load condition 1 - the vertical pull at the front causes the rear to drop slightly (below the level of the ground plane). Obviously if the bracket is set on a flat plane that extends the distance between all 4 bolt holes, this couldn't happen; and my simulations are flawed.

Lumas has uploaded 16 CAD models & has left 66 comments.
Manolo Valenzuela over 11 years ago

@Tim Titus - The bolt was clearly specified in dimension, so the constraint area should be the bottom face of the bolt head, No more - No less

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
George Hare over 11 years ago

@Manolo Valenzuela - That is true, but the SAE spec for the minimum bearing surface of the bolt is 0.552, not 0.558??

George Hare has uploaded 1 CAD models & has left 2 comments.
Tim Titus over 11 years ago

@Manolo, Yes that is probably a more accurate way of testing. I am not sure it would make that much of a difference when it comes to the results, but yes your way is the most correct one. I guess it also depends if they are using washers or not for the test after printing the parts. I can't imagine them straight bolting the part down without a normal washer and/or a spring washer if they were mounting it on a real plane.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Scott over 11 years ago

Please provide the torque specification for the four 0.375-24 AS3239-26 machine bolts (in either in-lbs or N-m).

Scott has uploaded 2 CAD models & has left 1 comments.
Manolo Valenzuela over 11 years ago

Winroth LLC - You do not need the torque to be applied to the bolt, it will be considered "infinitely strong". (the part should fail not the bolt)

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
bj over 11 years ago

you do need to know the torque applied to the bolts if you consider pre-tensioning which would make sense.
Also I think Luke Maselkowski's question is interesting. How do you simulate a constraint which allows lift but blocks downward movement (when simulating in part mode..)?

bj has uploaded 75 CAD models & has left 128 comments.
andreas anedda over 11 years ago

If you consider the bolt to be infinitely stiff, it doesn't matter to wich part of the bolt you will apply the constraint: it won't move!
By the way...still no response from GE??

andreas anedda has uploaded 5 CAD models & has left 26 comments.
bj over 11 years ago

Pre-tensioning of (infinite stiff) bolts should have an effect on the stresses in the bracket itself. Perhaps GE is having difficulties to come up with a proper FEA template themselves.. ;-)

bj has uploaded 75 CAD models & has left 128 comments.
EDISON PHOENIX over 11 years ago

Dear Engineers,
After a long journey with more guidance we proudly presents this ultimate design for your review.
To make a perfect design for GE jet engine bracket, I worked with my college friends as “Elemental Design Team”. After designed more than 20 models finally we give our best design with 72 % mass reduction and with maintained results in all 4 loading conditions.
Mass of our design: 1.279 lb
Min Factor of safety: 1.54

Our model's special features are described clearly in the attached report file.
So please review our model and give your ratings[out of 5] for our work:
Elemental Design [Ultimate]

Regards,
Elemental Design Team

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
m.h.m over 11 years ago

nice challenge
i love it ......

m.h.m has uploaded 39 CAD models & has left 796 comments.
m.h.m over 11 years ago

@EDISON PHOENIX ,
excellent & outstanding

m.h.m has uploaded 39 CAD models & has left 796 comments.
EDISON PHOENIX over 11 years ago

@m.mokhtari, Thanks mate.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Sara Sigel over 11 years ago

Update on FEA and judging for Phase I of the contest from GE:

------------------------------------

1. GE will compute the weight of each entry and the entries will be ordered from lightest to heaviest.

------------------------------------

2. Starting with the lightest entry and proceeding until we have ten winners:
a. We will ensure that the entry fits within the exact faces of the original GE bracket design. Failing this test will disqualify the entry. Please note: Due to differences in CAD software, they will allow deviations up to 0.010” outside of the original part envelope.
b. We will perform four separate finite element analyses on each geometry using the loads described in the rules. We will use ANSYS, and we will assume an isotropic linear-elastic material model with Young’s Modulus = 110 GPa = 15,950 ksi and Poisson’s Ratio = 0.31. The bolts, pin and mounting surface will be treated as rigid bodies.
c. The maximum vonMises stress will be calculated; if this stress exceeds the yield stress (903 MPa = 131 ksi) the entry will be disqualified.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

Thanks Sara.
For this update only we are waiting.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Siddarth over 11 years ago

Finally, got the updates.....
plenty thanks to Sara......

Siddarth has uploaded 72 CAD models & has left 100 comments.
Sara Sigel over 11 years ago

@Edison.Phoenix and @Siddarth I hope this helps!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
EDISON PHOENIX over 11 years ago

Absolutely Sara. This is the most important update in our point of view.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
Siddarth over 11 years ago

right sara.......this update will change the track of this challenge by coming entries....

Siddarth has uploaded 72 CAD models & has left 100 comments.
andreas anedda over 11 years ago

thank you very much Sarah...finally some news. Nice that they talk about a mounting surface only 10 days before the end of the contest...

andreas anedda has uploaded 5 CAD models & has left 26 comments.
Lumas over 11 years ago

Is there any chance we could be supplied with the geometry for the bolts, pin and mounting surface GE will be using? Just so everyone is working with the same materials...

Lumas has uploaded 16 CAD models & has left 66 comments.
Siddarth over 11 years ago

Hi engineers,
Please see our fourth entry ELEMENTAL BIG BOY
ELEMENTAL "BIG BOY"
Give you suggestions
Waiting for your comments

Thanks and Regards

Siddarth DM
Elemental Design Team

Siddarth has uploaded 72 CAD models & has left 100 comments.
Sara Sigel over 11 years ago

@Luke.Maselkowski See the notes in the requirements section about the pin, bolt, and nut information.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Pit over 11 years ago

MuscleFrog - model#31

3D Impression test done successfully

Done by Joan (joan)

Thanks

Pit has uploaded 24 CAD models & has left 106 comments.
andreas anedda over 11 years ago

Hi Engineers. I have a question. How do i consider the contact between my bracket and the base surface? separated, friction, no friction, glued? any guess? I think the good way should be separeted, right?

andreas anedda has uploaded 5 CAD models & has left 26 comments.
Ioannis Skarlatakis over 11 years ago

That's a good question with more than one answers to fit... it actually depends on the load you apply and it is easy to realise that...
For example if you check the load condition 2, 3 & 4 some friction should be considered... while in load condition 1, separated would be an obvious choice. UNLESS there is glue between the surfaces however no one mentioned anything so far...
My personal rough opinion is to keep the contact as separated. But as an engineer I would also try to get some results with a couple of different factors to check the variation...that definitely will keep you on the side of known behaviours for your model.

The thing is that there is no point to use friction unless the GE engineers will use this B.C. in their simulation!!!

So, the question should go directly to the "Queen" @Sara...

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
andreas anedda over 11 years ago

Thanks @Ioannis... I asked it because i tried different constraints and results are totally different. In my opinion glued constraint doesn't make any sense, It makes everything so easy. The bracket gets indistructable, wich can be great at a first sight but it is only an illusion. I tried separatd and friction: the results are quite similar, so i think i will go for the one that stresses more the bracket....just to be safe =)

andreas anedda has uploaded 5 CAD models & has left 26 comments.
michele di sacco over 11 years ago

I agree with your considerations, but without rules specification, I suppose each one can give personal assumption on its project...

michele di sacco has uploaded 1 CAD models & has left 10 comments.
DB over 11 years ago

Hi Sara, Please could you answer these questions as we feel they are important:
- How are the GE engineers going to analyse these entries? Specifically, will they be using contact analysis between the pin and the bracket?
- If not, what are they using?
Thanks!

DB has uploaded 2 CAD models & has left 2 comments.
optimal_aj over 11 years ago

Yes I agree!
Sara, could we have more details of the analysis method that is going to be adopted.
thanks

optimal_aj has uploaded 2 CAD models & has left 3 comments.
andreas anedda over 11 years ago

Everything would be so easy if we had a screenshot explaining how the analysis will be done. Constraints, blots, base surface, pin and forces. It's impossible to work properly otherwise.

andreas anedda has uploaded 5 CAD models & has left 26 comments.
Ármin Fendrik over 11 years ago

Yeah, and element sizes would be great to have as well...

Ármin Fendrik has uploaded 49 CAD models & has left 105 comments.
Luis Tadeu Martins over 11 years ago

All awards for this contest are in effect for the Brazilian legislation?

Luis Tadeu Martins has uploaded 0 CAD models & has left 1 comments.
Pit over 11 years ago

Hey guys,
as far as I know, and from what I've studied in my degrees and work experience, a way to apply the safety factor of 8 (in this case) is to apply some requests 8 times which are applied in the bases . for example, in the case of an applied force of 8000 lb, 64,000 lb would be applied with a FOS8. in my model, which is installed with the international system, 35585N, in my analysis I applied 284.680N. The housing being divided into two slugs, 142.340N in each.
Increasing forces involve increased tensions. I only modify the design and the amount of material to withstand the stresses and stay below the yield area. well, based on changes to design and perform the analysis I have come to my result.

Pit has uploaded 24 CAD models & has left 106 comments.
sergio menegol over 11 years ago

turbina aeromodelos

sergio menegol has uploaded 0 CAD models & has left 4 comments.
Pit over 11 years ago

GE Jet Turbine Bracket Pit 201306

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

my first one...

Pit has uploaded 24 CAD models & has left 106 comments.
Alan over 11 years ago

Is there any data on frequency or what this part may encounter?

Alan has uploaded 0 CAD models & has left 13 comments.
andreas anedda over 11 years ago

Is it me or nobody is taking care of the base surface in the analysis?

andreas anedda has uploaded 5 CAD models & has left 26 comments.
simon over 11 years ago

does anyone know what the story is with the 0.050 feature rule, does this only apply to wall thickness?

simon has uploaded 19 CAD models & has left 81 comments.
Ryan Zehr over 11 years ago

@Simon, If the process follows typical 3d Printing then then answer is yes. It only will apply to wall thickness. This includes curves so make sure there is no Knife edges. They are unpredictable in 3d Printing

Ryan Zehr has uploaded 1 CAD models & has left 13 comments.
simon over 11 years ago

ok thanks basically fillet every edge then

simon has uploaded 19 CAD models & has left 81 comments.
Sara Sigel over 11 years ago

Note from the GE Team: The top 10 submissions to date have achieved at least a 75% weight reduction. If you’d like to be a top 10 finalist, keep working on those designs – and be sure to include the results of your simulations in your submission. Only three days left in the challenge!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Lumas over 11 years ago

Wow... some amazing entries coming in...

Lumas has uploaded 16 CAD models & has left 66 comments.
DB over 11 years ago

could someone confirm exactly when the deadline is and in what timezone? the countdown just says 1 day which is not very precise. Thanks!

DB has uploaded 2 CAD models & has left 2 comments.
Sara Sigel over 11 years ago

@DB Phase I ends on August 9th at 11:59pm UTC be sure to leave time to upload and get all the details perfect!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
engineer over 11 years ago

Very 'hot' challenge!

engineer has uploaded 64 CAD models & has left 460 comments.
Igor Lins e Silva over 11 years ago

Thanks for the info Sara!

Igor Lins e Silva has uploaded 58 CAD models & has left 91 comments.
Manolo Valenzuela over 11 years ago

and suddenly... a bunch of brackets were loaded

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Sara Sigel over 11 years ago

@Manolo It's the crunch time at the end when everyone is getting their work finished and uploaded. Let's see how many more jump into the mix!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Hadi Babaei over 11 years ago

if GE knew that one day should judge between 550 model , never started this challenge :)))

Hadi Babaei has uploaded 34 CAD models & has left 240 comments.
Hubert Baumgartner over 11 years ago

The most interessting thing of this challenge are the different ways to solve a problem. I am also surpriced by the number of entries for a simple bracket.
How many working hours are now in this project for free?
Don´t think about it and good luk to anybody!

Hubert Baumgartner has uploaded 6 CAD models & has left 31 comments.
Pit over 11 years ago

more than 160 free hours in my case... 500 engineers... more than 7000 free hours for the GE team... that's a really efficient project!! amazing!!

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

the server is collapsed... I'm trying to upload my last one and it's impossible...

Pit has uploaded 24 CAD models & has left 106 comments.
Amartesh Sehgal over 11 years ago

hello grabcad community! i know i am a bit late for this but can anyone clarify this for me? are we to consider singular stresses as our design stress..... was asking this because Sara mentioned earlier that if maximum von mises stress exceeds the yield strength, that entry will be disqualified.... many thanks!!!

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Pit over 11 years ago

finally uploaded...
Frog F1
thanks and good luck!!

Pit has uploaded 24 CAD models & has left 106 comments.
Pit over 11 years ago

(the picture is just to take your attention )
:P

Pit has uploaded 24 CAD models & has left 106 comments.
simon over 11 years ago

@amartesh as far as i understand the max stress must be under the limit. if you reduce the mesh size thiis will generally solve your issue and give you a more accurate result

simon has uploaded 19 CAD models & has left 81 comments.
Elemental Design Team over 11 years ago

@All ,Finally we present our eventual work for all of your review.

Behind this entry a lots of hardwork of so many engineers is there.So kindly review our work:
Elemental Design Eventual

We hope that the notch concept [described in our report] will be more helpful in this kind of static analysis.

Thanks,

-Edison phoenix
Elemental design teamv

Elemental Design Team has uploaded 0 CAD models & has left 4 comments.
Harbir Singh over 11 years ago

Will the contact conditions between parts be bonded or frictionless during the analysis? This plays a major role in shearing of part near the bolts as the part loses contact in frictionless case and there is no stress concentration, which in the other case is always a very large value.

Harbir Singh has uploaded 5 CAD models & has left 5 comments.
Tim Titus over 11 years ago

My final entry boys: Super Kraken

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Sara Sigel over 11 years ago

Large pictures may take some minutes to show up once they're submitted. Please be patient. Do not ZIP or create RAR files for your entry, this may be the problem with previews. If you still have issues, email sara@grabcad.com.

--------------

New entries do not necessarily show up at the top of the entry list - take a look at the last page if you don't see yours. I'm deleting any comments that mention this. If you have any questions about your entry being properly submitted, email sara@grabcad.com.

--------------

With many people uploading close to the deadline, upload as soon as you can! Do not wait until the final minutes to submit to avoid any technical problems. We wouldn't want anyone to be left out due to timing!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

The "generalelectric" tag is automatically added to your entry when you upload through the submit entry button. You shouldn't need to add it manually but double-checking if it's there is good to do if you can't find yours in the entries.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel over 11 years ago

Please keep this thread clear of verifying your entry submission. You can email me, sara@grabcad.com with these questions.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Amartesh Sehgal over 11 years ago

whats the exact time left for submission as of now?

Amartesh Sehgal has uploaded 12 CAD models & has left 21 comments.
Sara Sigel over 11 years ago

The Challenge ends at August 9th, 11:59pm UTC. Please do not wait until the minutes show to upload your entry - go for it now!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Paul Tripon over 11 years ago

it seems that the server didn't respond for uploads in the last 30 min. of the contest.

Paul Tripon has uploaded 75 CAD models & has left 2039 comments.
Sara Sigel over 11 years ago

Please note: I just migrated all private entries to public.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tim Titus over 11 years ago

708 Entries. Absolutely amazing! Good luck to all contestants!

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Sara Sigel over 11 years ago

Please note that the entry number will fluctuate as we clear out any empty projects and process those made at the deadline (our system takes some time to catch-up). I want to say thank you to EVERYONE for the great discussion and all the hard work in each entry. It was truly inspiring to see your ideas evolve with each iteration and set of feedback!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Harbir Singh over 11 years ago

Can we check who all have downloaded our model?

Harbir Singh has uploaded 5 CAD models & has left 5 comments.
Pit over 11 years ago

From an engineering point of view, I believe that the judging criteria must be firstly the FEA success and finally the weight...

Pit has uploaded 24 CAD models & has left 106 comments.
Tan Wei Kok over 11 years ago

I think GE is likely to sort by weight, then FEA from lightest onwards. After they got the first 10 passed, it's game over for the rest :p

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
Pit over 11 years ago

I understand that's the game, but if I was a judge for this challenge, I would pay more attention primarily to the behavior of the bracket from the point of view of engineering, given its rigidity and ability to withstand the forces and moments, and then, from all that supported these tensions, choose the lightest ... that's my point of viewv

Pit has uploaded 24 CAD models & has left 106 comments.
EDISON PHOENIX over 11 years ago

@Pit, I accept your view.
Even GE needs more than 75% mass reduction, they should choose the top ten entries from above 75% mass reduced models only based on that FEA results [FOS].
I think first they filter the models with more than 75% mass reduction and then they will select the top ten models having higher FOS.

EDISON PHOENIX has uploaded 141 CAD models & has left 682 comments.
teigan over 11 years ago

FEA is a heuristic(quick and dirty compromise) tool. it is by nature less than accurate - even quirky. so we were all working blind; and winning is left to chance since we were not provided adequate testing parameter guidelines to make intelligent decisions about how far we could safely optimise.

since some of you invested a lot of time playing this random game, it would honour the 708 involved, if the judges relax their first round elimination to more than 10 brackets. furthermore, each of these entries should be allowed one chance to make quick adjustments to their designs to homologate with the official FEA test result.s

teigan has uploaded 9 CAD models & has left 167 comments.
Manolo Valenzuela over 11 years ago

August 23rd we will know who are the 10 finalists

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Hubert Baumgartner over 11 years ago

I think nobody had expected such a bunch of models. So the analyses of all of them will take longer than any bracket design :-) Maybe GE has to extend the selection time by some weeks, as they did for the entrie phase.

Hubert Baumgartner has uploaded 6 CAD models & has left 31 comments.
Tan Wei Kok over 11 years ago

Sadly, number of entries is relative to then amount of monetary rewards =(

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
teigan over 11 years ago

did you notice that despite differences in approach, our proposed reductions level off at about 90%?. that isn't a coincidence. it isn't a universal constant because the level of inefficiency of the original bracket determines the percentage. however, there is always a reliable predictable upper limit to system optimisation.

teigan has uploaded 9 CAD models & has left 167 comments.
Sara Sigel over 11 years ago

I removed a few posts for content. I know it's tough waiting for the results. Any comments posted here should be professional and constructive. Please note, Phase II starts on the 23rd - it isn't the public announcement date.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
ibrahim over 11 years ago

Hi everyone. Check this out --> http://en.wikipedia.org/wiki/Topology_optimization

ibrahim has uploaded 8 CAD models & has left 8 comments.
Tim Titus over 11 years ago

3d printing is a quite new thing to the market, and it has the tendency to make you think that a radical new software-optimized design will be the lightest and the strongest... however I have come to find that the simplest and least complex of structures is both the strongest and the lightest.

I hope GE does not mark us down for designs that are not exceptionally radical and don't have a complex, only-possible-via-3d-printing mesh design. After all, they are seeking the lightest design while being strong. Complexity can be beautiful, but does not necessarily produce a better result than the old tried and tested engineering methodology.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Eduardo Schoenknecht over 11 years ago

3D printing has its own limitations as well. I'm pretty sure maximum material stress is different from a machined part, and it will also be different in horizontal plane and vertical axis. I believe all our FEA tests are quite far from reality. There are also support and warping issues, but all evolving quickly lately. I believe this challenge was a really nice worldwide brainstorm. Tim, 3D printing is opening a lot of possibilities but I agree that simplicity and elegance will always win, even more when impact, vibrations and fatigue come to the game.

Eduardo Schoenknecht has uploaded 4 CAD models & has left 22 comments.
teigan over 11 years ago

typical mode of failure for DMLS parts under load - is shearing apart precisely along the X, Y, or Z build plane. they post process the part to melt away the inherent granularity, but in the end it still behaves much like a macro crystalline.

teigan has uploaded 9 CAD models & has left 167 comments.
Michael Jenkins over 11 years ago

Will GE post resultant updates through each Phase or just at the end?

Michael Jenkins has uploaded 1 CAD models & has left 6 comments.
Sara Sigel over 11 years ago

@Tim and all. As stated in the Challenge rules and requirements, GE will be focused on light weight brackets that meet all guidelines and pass all load conditions. Any consideration of experimental designs comes secondary to meeting the minimum requirements and reducing weight.
--------
@Michael GE will be sending updates but they do not coordinate with the end and start dates for each phase. Finalists will be contacted by the 23rd but the public announcement will not come until after that time. You will hear some updates before the end of the Challenge though, so stay tuned!
--------
For anyone looking to speak more about 3D printing and other innovations in MFG, please contact me at sara@grabcad.com as I have a special opportunity to share with you!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tan Wei Kok over 11 years ago

Think there are a lot of uncertainty in 3D printed parts performance, which is why GE has a Phase 2 in place to verify FEA results. I had an opportunity to help a friend on failure analysis for his PLA printed parts the last couple of weeks. Printed parts behave differently to what we get in FEA.

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
DWP over 11 years ago

@Tan Wei Kok Filament printing was invented to give to the boys the tool for making plastic roses for their girlfriends. Female Extensive Attention is unpredictable and may not apply :) In simple words, RepRap won't fly...

DWP has uploaded 2 CAD models & has left 33 comments.
Петар Трлајић over 11 years ago

so phase 2 starting in few minutes or when?

Петар Трлајић has uploaded 47 CAD models & has left 842 comments.
Tim Titus over 11 years ago

@Sara,
So the finalists have already been notified I'm assuming based on your comment above?

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Eduardo Schoenknecht over 11 years ago

@Fidel Chirtes Reprap does have somethings in common with other printing methods, and there are a lot of people doing amazing innovations with this "amateur" tool. Of course reprap won't print aerospace parts, but some of them can fly! http://www.youtube.com/watch?v=MGJWbTosdfs

Eduardo Schoenknecht has uploaded 4 CAD models & has left 22 comments.
Eduardo Schoenknecht over 11 years ago

Did someone get notified? I didn't :( Going to the have a beer anyway... Cheers Tim!

Eduardo Schoenknecht has uploaded 4 CAD models & has left 22 comments.
Tan Wei Kok over 11 years ago

@Fidel That's why he is researching to push the limit of filament printing. We are getting quite interesting results recently =)
@Eduardo Nice video. Thanks =)

Tan Wei Kok has uploaded 22 CAD models & has left 153 comments.
Michele Cantatore over 11 years ago

Ciao Sara, in these days I had more time to read the comments of this blog and I was taken from the theme of "envelope".
In my opinion everything should be clear in the "requirements" section and we should not read material’s characteristics, boundary condition, and so on , important data from GE, reading your answers to the questions of the other challengers.
In the requirements about the envelope we read that:
“The optimized geometry must fit within the original part envelope”, considering the model that I have posted they are inside the envelope but if I read your answer (coming from GE ) about this theme “We will ensure that the entry fits within the exact faces of the original GE bracket design. Failing this test will disqualify the entry” it could happen that my models could be disqualified already in the phase a of the judgement process because the length of the holes is different from that of the original bracket.
I think that this situation is not correct because you don’t take in account a lot of work produced from me and other challengers, in same situation, because the GE requirements were not clear.
Considering this misunderstanding about the envelope I hope that my models and those of other challengers in the same situation could be judged only considering the stress and weight reduction.
Have a good week.

Michele Cantatore has uploaded 60 CAD models & has left 40 comments.
richard kilshaw over 11 years ago

'Part envelope' is a standard term commonly used and understood by CAD designers. Regardless of final shape, the designed part cannot exceed the packaging envelope. How do you ensure your designed part does not exceed the envelope? Easy, always boolean intersect the part envelope solid with your designed solid after all authoring. Bolt mounting flats that were shallower than the part envelopes would have been acceptable in this competition (passing the load requirements is another story) but adding material here would clearly not be. Hope the boolean tip helps for future competitions.

richard kilshaw has uploaded 2 CAD models & has left 5 comments.
Michele Cantatore over 11 years ago

@kilshaw: I think that this challenge is a design challenge not a mathematical problem. Many questions from other partecipants about the theme of envelope show clearly that the requirement was not clear. In my opinion all the partecipants had to receive by email the details coming from GE so everyone could be free or not to correct the own design.
In any case it’s not so important this problem at moment because I think that the GE engineers will have the mental flexibility and the competence to choose the best designs.

Michele Cantatore has uploaded 60 CAD models & has left 40 comments.
Stephan H. Tobias (BuseHase) over 11 years ago

anyone get a notification?

Stephan H. Tobias (BuseHase) has uploaded 37 CAD models & has left 198 comments.
Sara Sigel over 11 years ago

We have asked all finalists to quietly work on Phase II until the official announcement from GE next month. If anyone is looking for something interesting to do in the meantime, send me an email at sara@grabcad.com!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Eduardo Schoenknecht over 11 years ago

Congratulations to finalists. I'll quietly leave...

Eduardo Schoenknecht has uploaded 4 CAD models & has left 22 comments.
Alex over 11 years ago

Quietly asked ?!!! Indeed.... Ha ha ha....

Alex has uploaded 4 CAD models & has left 8 comments.
Hector Levatti over 11 years ago

Hi All, we know there are 689 valid entries. But, anybody know how many participants there were in this Challenge?

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
Sara Sigel over 11 years ago

@Hector I can find that number for you. We'll release that with the upcoming public announcement.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Robert Melvin over 11 years ago

This project generated alot of community involvement and interest and I think it is unfortunate to break that engagement and excitement by moving the process behind the scenes.
In design and architecture there are juried design crits and they are not secret. I believe there is much value in opening this process to the community so we can understand how the balance of factors was weighed, how projects were selected or not, and what caused some to be received more strongly than others,...
Feedback and insight from a public juried crit can strengthen and improve the community, educate us, improve the challenge work submitted, improve its focus and relevance, and is something I expected to see and would like to see in the future.

Robert Melvin has uploaded 2 CAD models & has left 6 comments.
Sara Sigel over 11 years ago

@Robert We will be reconnecting in a few days with LOTS of information on entries, engineers, and the evaluation process. Sorry for the brief quiet period while we collect information and create some promotional content like videos. You'll really like them, sorry again for the wait!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Hector Levatti over 11 years ago

I agree with Robert. We are waiting for all that information that is going to be very useful for all of us. Thanks Sara

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
Alan Grantz about 11 years ago

I hope the FEA results obtained by GE will be published for all of the finalists as well as the ranking methodology e.g. (weight savings x factor of safety + ??)

Alan Grantz has uploaded 1 CAD models & has left 2 comments.
Ármin Fendrik about 11 years ago

Congrats everybody :)

Ármin Fendrik has uploaded 49 CAD models & has left 105 comments.
Sara Sigel about 11 years ago

It starts with an announcement of the potential winners! There will be videos, blog posts, and more to follow. Congratulations to everyone...

GE blog post: http://www.gereports.com/meet-the-makers
GrabCAD blog post: http://bit.ly/16BvTD1

Stay tuned for more content around the printing and testing of the finalists' brackets!

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tim Titus about 11 years ago

Seriously disapointing results. I am positive that at least 2 of my designs were lighter than the finalists while passing all FEA requirements. FEA TESTING DETAILS FOR EACH MODEL PLEASE!! It seems design was a factor after all for some of the results (a reason for especially choosing the BONE model ,which is awesome looking), however I was told that it was NOT a factor and that weight was the only consideration. Even a couple of my designs were more cool looking than some of the finalists, I mean why choose models that have useless geometry built in that only makes it heavier while not increasing strength?? Thanks for using my rendering, although the fact that you used the first one I made makes me feel like you didn't even consider the models I made after that as some of them had even better renderings. Very frustrating results, and I know I'm not the only one.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Ioannis Skarlatakis about 11 years ago

@Tim - I agree with the publishing of the Test Reports in Grab Cad. In fact this is the least they can do to prove that the participants of this challenge were treated equally... I will stop here... nothing personal

@Juno - I am not fighting you... You might be right, you might be wrong. Nevertheless It is not necessary to get angry in this level. There are some announcement out there but, I think it is worth to wait for something more official...

@Tan - Two things mate I love your work I liked your specific model but you cannot confuse these two challenges... The bracket it was for money while the "ModVic Steampunk Wheelchair" was to help a guy from around the world... Please be proud for your team and for yourself as everyone is Proud to be a member of this community... Beside you don't know if your model will be tomorrow's potential project for another guy who just liked your edition more than the rest, do you?

I am not trying to put nice colours on your frustrated faces. I am just thinking that always and in every challenge will be a winner and a loser. It just happens! Sit back and review, say what you have to say and be better next time... This is professionalism and this is life. There are more serious things to upset you... not a challenge
I am sure that we don't have to be mean instead we have to be smart...

Respect to all of you guys

Ioannis Skarlatakis has uploaded 25 CAD models & has left 428 comments.
Sara Sigel about 11 years ago

I understand your frustration in not being able to know everything about the results at once. There is much more information to be given in the next few weeks, which includes testing. Designs that exceeded the level of weight reduction but were not selected did not meet one of the stated requirements, above, which includes FEA testing. The winners selected had the highest weight reduction and passed all of these requirements. For that, we should congratulate them!
...
As a reminder, I will remove any comment that doesn't meet our professional Community guidelines. This includes any that call-out specific people in a negative way or general opinion statements. It has been said that people are unhappy that FEA testing results weren't released with the winners. I will get this feedback to GE. There is no need to repeat it. Those comments will be removed. Let's show everyone watching that we support our members for their efforts. They are already impressed with your engineering skills, not let's show them your professionalism. If you do have anything else you want to express. Email me at sara@grabcad.com and I will make sure your voice is heard by the right people.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Sara Sigel about 11 years ago

No worries, @Draftek.Design. We are a data company and a data Community. We'll share as much data as we can with everyone! The Challenge isn't over yet so there is much more to come.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Eduardo Schoenknecht about 11 years ago

I'm looking forward to see FEA results, specially:
GE jet engine bracket V2
I have a lot to learn from it

Eduardo Schoenknecht has uploaded 4 CAD models & has left 22 comments.
Dawn Morgan about 11 years ago

@Pawel Gorka - - Hi, there are links to the CADs for the 10 finalists on the following link - - you might find this helpful http://www.genewscenter.com/Press-Releases/GE-Unveils-the-Ten-Global-Finalists-for-its-Open-Innovation-Jet-Engine-Bracket-Design-Quest-42a9.aspx

Dawn Morgan has uploaded 0 CAD models & has left 8 comments.
Sara Sigel about 11 years ago

I will work on getting data points for each Phase I finalist and those that exceeded weight reduction of any Phase I finalist in the following areas. I don't think I was clear enough before that this is something I'm working on getting for everyone.
- Total mass and percentage weight reduction
- Did it pass the envelope constraints?
- Did it pass FEA / load conditions? Detail any areas that it did not pass.
- Did it pass minimum material feature size?

If you feel that other information should be included, let me know. Please note: I removed any comments that did not introduce new information or questions.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Dawn Morgan about 11 years ago

Sara, may we have the details of the mesh sizing used, the contact conditions and the fixed surfaces in the FEA analysis also? - - I think there is still some ambiguity there. Thanks

Dawn Morgan has uploaded 0 CAD models & has left 8 comments.
Pawel Gorka about 11 years ago

@Dawn Morgan --Thank you.

Pawel Gorka has uploaded 1 CAD models & has left 1 comments.
Scott Frash about 11 years ago

Sara, Im curious why designs with lower factor of saftey and less volume reduction were chosen over my design? I know it was a judgment call, but I'm just curious what it was that made these other designs better, according to the guidelines my design was technically ahead of about 90% of the chosen designs.

Scott Frash has uploaded 2 CAD models & has left 10 comments.
Sara Sigel about 11 years ago

@Scott I'm creating a table that will help shed light on that and show why each finalist made it to the next round. I'm sorry I don't have this to give to you yet, but it's coming.

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Manolo Valenzuela about 11 years ago

I would like to see that table, I have the same curiosity, My last one (K-Cargo) was the ugliest but was lighter than 98% of total and it pass the FEA withno problem.

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Alex about 11 years ago

From the very beginning of this "serious contest" everybody expect "amazing solutions for GE!". At the end - result is less than "amazing", very very greyish.

Alex has uploaded 4 CAD models & has left 8 comments.
Manolo Valenzuela about 11 years ago

Avoiding missundertands - I mean, 98% of total solutions posted

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Matthew Stonebraker about 11 years ago

Hey Manolo, with 683 entries, if yours was lighter than 98% of the entries, that means there were ~13-14 entries lighter than yours. Assuming no one would enter a part that failed the FEA, is it really hard to believe that the Top 10 passing entries would be above the 98% line?

Matthew Stonebraker has uploaded 6 CAD models & has left 51 comments.
Manolo Valenzuela about 11 years ago

8 ) your are right Matt... the 98% was just a number, some of the 10 selected are over my volume.

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Scott Frash about 11 years ago

I have a hard time understanding how parts with holes in the middle of stress paths beat out streamlined designs without the holes. From my understanding members that are in tension (which is what is going on here) are always stronger if they do not have holes as these are a source of stress concentration. I have always understood that parts should be as smooth as possible with minimal changes to cross section area for maximum strength vs. weight properties. I am looking forward to the FEA, seems like a good learning opportunity!

Scott Frash has uploaded 2 CAD models & has left 10 comments.
René about 11 years ago

Hey guys. Obviously GE thought of an optimized bracket itself already. Check out this video:
http://youtu.be/andW3VMGOJ0

René has uploaded 2 CAD models & has left 27 comments.
Manolo Valenzuela about 11 years ago

They played with our feelings...

Manolo Valenzuela has uploaded 75 CAD models & has left 44 comments.
Tim Titus about 11 years ago

@Rene, thanks for the video.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Tim Titus about 11 years ago

@Sara

"@Scott I'm creating a table that will help shed light on that and show why each finalist made it to the next round. I'm sorry I don't have this to give to you yet, but it's coming."

Is this coming out before the end of Phase II?

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Sara Sigel about 11 years ago

@Tim That is the plan but we don't have a hard date to share it yet. We're making sure it's organized in a way that helps anyone following along learn and build skills for future projects. Thanks for checking in :)

Sara Sigel has uploaded 1 CAD models & has left 1843 comments.
Tim Titus about 11 years ago

Phase II results in Mid-December? it's a wonder GE is able to produce anything moving as slow as they do...

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Hector Levatti about 11 years ago

Any news about the challenge? And what is about the feedback? Regards.

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
andreas anedda about 11 years ago

http://seenive.com/v/1020488587965595648

andreas anedda has uploaded 5 CAD models & has left 26 comments.
Stephen Nyberg about 11 years ago

That is cool seeing the actual brackets!!!

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Arno Gramsma about 11 years ago

I just uploaded the pictures of the printed model in 316L we printed last week in our AddLab by KMWE, see also https://grabcad.com/library/volume-reduction-68-65-75-ge-1/files/IMG_0918.JPG

Arno Gramsma has uploaded 1 CAD models & has left 14 comments.
Hector Levatti almost 11 years ago

Congratulations to the winners!

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
Hector Levatti almost 11 years ago

What is about the criteria of selection?

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
Tim Titus almost 11 years ago

Months and months later and we still don't have info on the testing procedures, what the simulation settings were, or why many of the lower weight models didn't pass (even though they passed our simulations based on the exact info given). The challenge was extended to provide us simulation testing information, and we never got it. In the end, luck was a big factor as no one had any idea what the max tolerances were allowed without proper simulation details. I feel I wasted months of my time for something that had too much of a luck factor, rather than a genuine engineering factor.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
Joshua Stults almost 11 years ago

I'm sure I'm not the only one still interested in seeing the detailed feedback. Any update on when it will be posted? Thanks!

Joshua Stults has uploaded 0 CAD models & has left 2 comments.
Joshua Stults over 10 years ago

Are you still planning on posting detailed feedback?

Joshua Stults has uploaded 0 CAD models & has left 2 comments.
Hector Levatti over 10 years ago

Good question

Hector Levatti has uploaded 4 CAD models & has left 6 comments.
Tim Titus over 10 years ago

The whole GE challenge was a sham. Broken promises, wasted time, less than great judging.

Tim Titus has uploaded 14 CAD models & has left 316 comments.
the dude over 10 years ago

sounds like we have a sore loser ^^^^

the dude has uploaded 0 CAD models & has left 32 comments.
Martin Dirker about 10 years ago

I tend to agree with Tim. GE made some commitments and did not meet them. Maybe they 'overpromised'

Martin Dirker has uploaded 5 CAD models & has left 26 comments.
Stephen Nyberg about 10 years ago

I think this has been one of the best challenges GrabCAD has had to date and while there were a few shortcomings with communication, I think that GE, GrabCAD and the GC community gained a lot in not only the amazing results from this challenge but also in moving the world of engineering forward with open collaboration. What promises did they break or commitments did they not meet? There were almost 700 entries for the judges to go though and they were not just looking for the ones they thought were pretty - but for the entries that met the requirements stated in the challenge and performed the best. It would have been nice to see the the process and testing of the entries more during the process but I think that this was the first challenge of this type and future challenges will improve upon this one.

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
derek thornton over 6 years ago

is the original bracket design available? can't see it.

derek thornton has uploaded 0 CAD models & has left 1 comments.
Stephen Nyberg over 6 years ago

@derek thornton
Under the requirements on this page there is button to "Download specification" - this is a .STP file of the original bracket.

Stephen Nyberg has uploaded 127 CAD models & has left 1226 comments.
Haroon Mohammed over 2 years ago

so when this project was released, which softwares and analysis did people use for computing this ? was topological optimization still a common thing on 2013 ?

Haroon Mohammed has uploaded 0 CAD models & has left 3 comments.
Arno Gramsma about 2 years ago

Hi Harron, no this was not common we then used Siemens NX and special software from TU Delft. So this was challenging back then.

Arno Gramsma has uploaded 1 CAD models & has left 14 comments.

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Deadline Passed
Total entries 628

Who’s in the jury?
Kaspar Kiis
GrabCAD, Mechanical Engineer
Jared Wolfe
Sub-Section Manager of the Advanced Externals Technologies team at GE Aviation
Gregg Wilson
GE, Section Manager of the Advanced Externals Design team
David Abbott
Mechanical Engineer, GE
Dr. William Carter
Mechanical Engineer, Additive Manufacturing Laboratory, GE Research

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Exciting engineering challenges with great prizes

GE jet engine bracket challenge

Participants in this challenge will use additive manufacturing as the basis for optimizing an existing aircraft engine bracket.

The part

The test section

PHASE I:

PHASE II:

Requirements

Rules

Prizes

About the jury?

About GE

410 comments

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