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SimScale Truck Underrun Protection Challenge

Medium

This Challenge gives you the opportunity to show your skills in the design of a lightweight, robust and eye-catching truck underrun protection system.

What is an underrun

Underrun protection devices at the rear end of trucks help to increase traffic safety significantly. To enhance the safety of passengers during a car accident involving a passenger vehicle and a large truck, trucks are required by law to have an underrun protection system at their rear end. This device keeps colliding cars from running under the truck which would have disastrous consequences for passengers within the car. The underrun protection needs to be stiff to ensure its performance during a crash while being as light as possible for fuel efficiency reasons. Last but not least, it should be aesthetic to make the truck look as cool as possible.

About this Challenge

The challenge is to come up with a new design for an underrun protection that is light, stiff and aesthetic. Both law as well as the installation situation pose some specific design requirements that have to be met. All the design requirements are described in more detail in the text and drawing below.

Performance requirements

The structural performance of your design is critical. Therefore the performance of your design has to be validated using the SimScale engineering simulation platform. The SimScale platform runs in your browser, so that there is no installation necessary. The required analyses can be done using the Free plan that comes completely free of charge. The simulation details to set up your analysis as well as links to a video tutorial, a documented tutorial and an example project that you can import into your SimScale platform workspace are given below.

Resources for this Challenge

- SimScale platform
- YouTube tutorial video
- Example CAD project in STEP file which is used to explain the analysis and technical details of the Challenge in PDF can be downloaded from 'Download specification' button below.
- Step by step tutorial

Choosing winners

The main metrics for winning this Challenge are weight and stiffness. Besides that, the jury is looking for creative, aesthetic designs. The designers that make it to the final round will be asked to share their simulation projects with the SimScale team after the Challenge has ended. The SimScale team will then check on the structural performance of your design and validate if the criteria are met.

Requirements

  • You must include:
    - STEP/IGES model of your design
    - The mass of your design (density of the material is given below), which will make it easier for the jury to evaluate the designs
    - One screenshot of the deformation field and the von Mises stress field of your design under P1 load case (see below) to prove the validity of your design.

  • You are encouraged to include:
    - Native CAD file format
    - Rendering
    - Screenshots of all load cases

  • Design an underrun protection device that meets the design and performance criteria while being:
    - light
    - stiff
    - aesthetic
    -Symmetric (requirement added on Jan 31)

  • Use the SimScale platform to validate that your design meets the structural requirements. The necessary analysis can be done for free after signup on the SimScale platform.

  • Dimensions:
    - Height of the shield front: 100 mm
    - Width of the shield front: 2500 mm
    - Relative position of the fixation holes: See drawing
    - Minimum material feature size (wall thickness): 10mm
    - The shield front (2500mm x 100mm) including the three load areas as well as the eight fixation holes and their diameter are not allowed to be changed. Everything else is up to the designer.

  • Stiffness:
    - Allowed maximum deformation: 40mm
    - Allowed maximum von Mises stress: 355 MPa
    - There are three different load cases (P1, P2, P3) which have to be tested
    - The load is applied as a pressure on a specified area, one load at a time
    - Area size is 200mm x 100mm
    - Positions P1, P2, P3 of the areas are documented in the technical drawing
    - Applied pressures are:
    ............ P1 = 12.5 bar = 12.5 × 105 Pa
    ............ P2 = 25.0 bar = 25.0 × 105 Pa
    ............ P3 = 12.5 bar = 12.5 × 105 Pa
    - Material: SimScale Standard Steel (Young's modulus: 205 GPa, Poisson's ratio: 0.28, Density: 7870 kg/m3)

  • Analysis hints:
    - Use the Automatic tetrahedralization mesh operation (simple and fast)
    - Use the Static stress analysis type in the Solid mechanics section
    - For more questions and hints, please have a look at the provided video tutorial

  • Design hints:
    - To be able to apply the loads with SimScale, you have to split the shield front such that the load areas appear as separate faces (have a look at the example STEP file)
    - Design the whole model as one part, not an assembly (for a straightforward analysis setup)

Download specification

Rules

  • The competition is open to everyone. Multiple entries are acceptable. Team entries are welcome - prize will be transferred to team leader. Participants may only win one prize per Challenge.

  • Tag your entry with “UNDERRUN” when uploading to GrabCAD. If you submit through the "Submit entry" button, this should be added automatically. Only entries with valid tag will participate. Only entries uploaded to GrabCAD through the "Submit entry" button on this Challenge page will be considered an entry. Private entries are not eligible.

  • By entering this competition, you
    1. Warrant that the work is your original work.
    2. To the best of your knowledge, it is not, and has not been in production or otherwise previously published or exhibited.
    3. Neither the work nor its use infringes the intellectual property rights (whether a patent, utility model, functional design right, aesthetic design right, trade mark, copyright or any other intellectual property right) of any other person.
    ______________________
    If you think an entry may infringe on existing copyrighted materials, please email challenges@grabcad.com.

  • Applicants are not entitled to any compensation or reimbursement for any costs. The applicant’s participation shall not constitute employment, assignment or offer of employment or assignment.

  • The sum of the Awards is the total gross amount of the reward. The awarded participant is solely liable for the payment of all taxes, duties and other similar measures if imposed on the reward pursuant to the legislation of the country of his/her residence, domicile, citizenship, workplace, or any other criterion of similar nature. Only 1 award per person.

  • Only public entries will be considered. Any private submissions will be made public at the Challenge deadline.

  • We will release the finalists before the final announcement to give the Community an opportunity to "vote" for their favorites in the comments. The jury will take these into consideration when picking the final winner. This new addition is based on feedback from you!

  • Winning designs will be chosen based on the rules and requirements. This Challenge ends on February 19, 2014 (11:59pm UTC). Winners will be announced by March 19, 2014.

  • SimScale retains the right to promote and publicize entrants and their design work.

  • Void where prohibited.

Prizes

Google Nexus 7 for the winner and cash awards for TOP 4 places

1st Prize

$500 cash + Google Nexus 7 32GB + GrabCAD scrapbook

2nd Prize

$350 cash + GrabCAD scrapbook

3rd Prize

$250 cash + GrabCAD scrapbook

4th Prize

$150 cash + GrabCAD scrapbook

5th - 10th Prize

GrabCAD scrapbook

About the jury?

The jury will be comprised of SimScale and GrabCAD experts.

About SimScale

SimScale is a simulation platform that allows engineers and scientists to analyze the physical behavior of their products with a standard web browser. SimScale gives them access to powerful simulation technology and practically unlimited computing power – on demand, collaborative and based on a flexible pricing model. SimScale helps engineers to create better products in shorter time.

118 comments

  • Frederik Vollbrecht

    Frederik Vollbrecht 6 months ago

    Thats what I call german "Genauigkeit"! No more questions by my side. Tolle Challenge.

    Frederik Vollbrecht has uploaded 39 CAD models & has left 147 comments.
  • David Heiny

    David Heiny 6 months ago

    :) - glad you like it, Frederik!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Bert van Haren

    Bert van Haren 6 months ago

    A tempting challenge. Perhaps I will have a go at it.
    I will definitly have a serious look at Simscale. I've never heard of it before. Might be something for me after my retirement next year when I will no longer be able to use the licences from my work.
    Does Simscale also do multibody dynamics?

    regards,
    Bert

    Bert van Haren has uploaded 13 CAD models & has left 48 comments.
  • Hevi

    Hevi 6 months ago

    Ok, cool... but I think it's hard to do design which looks cool and met the stif. and weight req. The lightest design will look... hmmm... cheap ;) That is my opinion :D

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • David Heiny

    David Heiny 6 months ago

    Bert, we are looking forward to your design! Regarding multibody dynamics capabilities: Currently there is no such functionality available. However it's a generic CAE platform, so there might be MBD functionality integrated in the future.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    Hevi, that's true - it's definitely a challenging task! However the stiffness requirements (max. displacement, max. stress) are quite restrictive such that a valid design will need quite some material. So hopefully the danger of "looking cheap" is not that high. But let's see :)!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hevi

    Hevi 6 months ago

    BTW - about your platform... am I able t do flow/heat simulation for injection/thermoforming mould?

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • Hevi

    Hevi 6 months ago

    2nd thing - you should "mark" on some screenshot of "Underrun Protection" model surfaces which are NOT allowed for any changes, for example holes, mount etc etc but plz mark all surfaces which are NOT allowed for changing :) (I know that I wrote this 2x ;) ...just for sure :)

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    Although the geometrical restrictions are very clear I will agree with Hevi.
    It would be very helpful to have a screenshot with the restrictions marked.

    P.S.
    So nice to have challenges like this one along with so detailed requirements Frederik Vollbrecht couldn't put this better :D
    This Challenge is definitely "HOT" I look forward to submit my model...

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • David Heiny

    David Heiny 6 months ago

    Hevi, Ioannis - thanks for the suggestion! We will create another screenshot/drawing where we mark the surfaces that are not allowed to be changed. In general this is really just the front shield and the "inner edges" of the holes with their relative position to the front shield. I will add the drawing as soon as possible!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hevi

    Hevi 6 months ago

    Ok, cool :) Another thing - production restrictions? Any? Maybe this should be just welded parts... maybe we should use typical steel profiles, etc

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • David Heiny

    David Heiny 6 months ago

    Hevi, there are solvers for flow and heat problems available, but not yet for viscoelastic fluid flow applications such as injection moulding.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    Hevi, regarding the production restrictions: We decided not to include them, since the challenge is already quite challenging :)! It's nice if one takes care of it, but the stiffness, the weight and the look will be the decisive factor.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hevi

    Hevi 6 months ago

    Ok, so I wait for the screenshot with marked surfaces...

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • benzaoui

    benzaoui 6 months ago

    Can you tell me the place to use this design
    or the mechanism to Linking Design
    I want pictures

    benzaoui has uploaded 7 CAD models & has left 17 comments.
  • Sara Sigel

    Sara Sigel 6 months ago

    Updates to the image and downloads have been added - take a look!

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • niki_malchev

    niki_malchev 6 months ago

    My guestion is about the minimum material feature size (10mm), is it regarding the whole truck underrun or just the shield front?

    niki_malchev has uploaded 4 CAD models & has left 7 comments.
  • David Heiny

    David Heiny 6 months ago

    Benzaoui, the challenge image at the top of this page shows a (slightly different kind of a) truck underrun protection. The one that shall be designed in this challenge will be connected via bolted connections to the frame of the truck.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    niki_malchev, the minimum material feature size applies to the whole underrun protection device.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hevi

    Hevi 6 months ago

    I think that this 10mm is a very good idea :) I like it :) I hte models with 0.5mm walll thickness just for correct FEM reasult..

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • Leonardo Alves

    Leonardo Alves 6 months ago

    Congrats Sara and GB team, It's amazing challenge.

    Leonardo Alves has uploaded 15 CAD models & has left 170 comments.
  • benzaoui

    benzaoui 6 months ago

    Mr - David Heiny- I'm talking about the background image of the trailer where you want to put this Design

    benzaoui has uploaded 7 CAD models & has left 17 comments.
  • DÈmonic LÒrd

    DÈmonic LÒrd 6 months ago

    Hi guys
    wanted to know how do I talk to about this design spec and materials do I talk bout it here or do I privite message someone? Thanks

    DÈmonic LÒrd has uploaded 10 CAD models & has left 7 comments.
  • Hevi

    Hevi 6 months ago

    @DÈmonic - I think you should do that here that we all can get that info... maybe it's important for the design :)

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • DÈmonic LÒrd

    DÈmonic LÒrd 6 months ago

    Ok Thanks

    I wanted to know what is the width for the shield front I know it's 100mm H,2500mm L, 10mm Thick
    does the width have to be 10mm same as the thickness or can it be wider like 100mm wide. and can you use more then one material so the main steel to hold all the load is that stardard steel but in addition are we allow to add in other material to reduce load and for looks too? thanks

    DÈmonic LÒrd has uploaded 10 CAD models & has left 7 comments.
  • David Heiny

    David Heiny 6 months ago

    benzaoui, I will try to provide such an image. The underrun protection device will be connected to the frame of the truck at the inner side of the fixation holes. This is why the 1060mm is important (that's the width of the truck frame). That's also the reason why the inner edges of the fixation holes are marked red in the technical drawing.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    DÈmonic, the thickness of the shield front is up to you - only the dimensions of the "front face" of the shield are fixed (100mm H, 2500mm L). The other global requirement is that the minimum material feature size is 10mm, so it can't be thinner than that. Also only one material (the main steel with the properties described in the specification) can be used (...and I think pure-steel will look great :) )v

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • BekirHan

    BekirHan 6 months ago

    I have a question about supports. How should we add supports to analysis case. Should we fix just from holes?

    BekirHan has uploaded 2 CAD models & has left 44 comments.
  • Ernesto Chavez

    Ernesto Chavez 6 months ago

    @David Heiny, is there a requirement for the kind of meshing parameters you want us to use when we start validating our designs? Is it enough to simply set the mesh parameters as a first order coarse mesh like in the step-by-step tutorial for our final designs or do you require us to go with something finer for more accuracy? Will accuracy of our final stress and displacement data be another metric for winning this challenge?
    I've been trying to run a simulation with a second order fine mesh for some time but I keep getting an error status in the job status box despite having filled in all the mesh and simulation parameters correctly.

    Ernesto Chavez has uploaded 4 CAD models & has left 20 comments.
  • David Heiny

    David Heiny 6 months ago

    @BekirHan: Yes, to fix the inner faces of the holes as supports is fine for the analysis.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    Ernesto, we didn't want to impose all the details of the analysis, so you should run your analysis the way you think it is accurate enough. In general, we are looking for a reasonable validation of your model. So there shouldn't be any obvious mistakes in the analysis but we are not looking for a detailed numerical analysis report with mesh studies etc.!
    I would advice starting with a first order coarse mesh (as shown in the tutorial) - the quick computing times will allow a fast validation and identification of potential critical regions in your design. Once you've reached a stable design, a more sophisticated analysis using a second order mesh might be interesting. However choosing "fine"+"second order" in the auto-tet mesher aims at a quite high node count for which the 1-core-machines of the free-plan might be too small. You might want to start with "coarse"+"second order", which should give a good mesh as well.
    If the error persists, the SimScale support team is happy to take care of it (support@simscale.de)!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    Hi everybody,
    After watching the video tutorial, which by the way is very detailed, I've noticed that nowhere has been mentioned the F.O.S.
    Nevertheless, it is not difficult to calculate this separately, isn't it?

    But then another query came to my mind regarding the material...
    On the specification has been requested a limit on the Von Mises as that of 355MPa but nowhere the yield stress of the material??? :0

    I am aware that the there is no such a section on the material details in the simulation however I presume that is an important factor for linear static mode. Therefore I would like kindly to ask how this works without defining the linear boundaries of a material.

    Please forgive me if I missed any info and thank you for all the answers so far.

    Best Regards
    Ioannis

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • David Heiny

    David Heiny 6 months ago

    Hi Ioannis,

    the idea behind the maximum stress of 355 MPa is that for these stress values, the steel will behave linear-elastic such that the type of analysis is valid. So you can think of the 355 MPa as the yield stress. But you are right - if one would have stresses above the yield stress, one would need to switch to a different material model where you supply the yield stress as a value. But for this challenge it is sufficient that you make sure that the stresses are not higher than 355 MPa where a linear elastic material model is still valid for the steel that is used.

    All the best,
    Daviv

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    And with "Daviv" I mean "David" :)!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    Hi everyone,
    I was asked about whether the manufacturing process of the underrun protection shall be considered in the design (and I answer it here such that everybody is on the same page): We decided not to include manufacturing limitations in this challenge. So it is nice if you address it in your design, but it won't be the decisive factor for winning the challenge. Think of it as an early design phase rather than a design that will directly go into manufacturing.

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Aimo

    Aimo 6 months ago

    Is this Simscale really slow when creating mesh with other users too? Or is it just me? It already has taken 20 minutes when Inventor made it less than 30 seconds.

    Aimo has uploaded 7 CAD models & has left 18 comments.
  • Tarek Zemri

    Tarek Zemri 6 months ago

    Can we have more détails about the space around the Truck Underrun Protection, that gives us more flexibility in new design, (images.....v

    Tarek Zemri has uploaded 25 CAD models & has left 40 comments.
  • Robert Kwiatkowski

    Robert Kwiatkowski 6 months ago

    I encountered a problem while running my simulation. It states:

    *ERROR in e_c3d: nonpositive jacobian
    determinant in element 2154v

    How can I see only this element? I think it is caused by mesher although there wasn't any warning displayed. Normally this is caused by elements that have nearly zero volume.

    Robert Kwiatkowski has uploaded 13 CAD models & has left 13 comments.
  • Anuj Kaushal

    Anuj Kaushal 6 months ago

    same problem....

    Anuj Kaushal has uploaded 73 CAD models & has left 4113 comments.
  • Alexander Fischer

    Alexander Fischer 6 months ago

    Hi Robert and Anuj, it may be caused by a problem with the geometry or as you mentioned by some degenerated elements. Unfortunately so far you can not see which element caused the error on the platform, but if you want me to have a look on your case, you can just share your project in the workspace to me (afischer@simscale.de). I'll be happy to help you.

    Alexander Fischer has uploaded 0 CAD models & has left 2 comments.
  • Alexander Fischer

    Alexander Fischer 6 months ago

    Hey Almo, you're absolutely right, it should not take that long. If you use the very coarse setting it should take under a minute in most cases. Did you get a mesh in the end? Of course you can share your project to me as well and I will have a look on it (afischer@simscale.de)

    Alexander Fischer has uploaded 0 CAD models & has left 2 comments.
  • Aimo

    Aimo 6 months ago

    @Alexander Fischer, I did get a mesh. I canceled that process and started a new, it took couple minutes to finish. I used coarse setting both times.

    Aimo has uploaded 7 CAD models & has left 18 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    It is not a request but a suggestion. A quick post by the jury on the entries of this challenge will maintain the validity of the models and as a result it will enhance the competitiveness. This is not exactly personal opinion it is more like a "true story" after taking into account other challenges. ;)
    And to be fair so far the jury is quite active and helpful...

    I'm saying all these as it would be such a pity for some to disqualified after investing so much time on their proposal.

    Regards

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • David Heiny

    David Heiny 6 months ago

    Ioannis, thanks for the suggestion! I will discuss with my colleagues the designs so far and post a comment if necessary! We also want to make sure that nobody is desqualified when investing so much time!! I'll come back later today!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Christos Georgoulas

    Christos Georgoulas 6 months ago

    Very interesting challenge! Can i make the sheild front to be something like an arc shape with the same dimensions or it should be all straight?
    I am asking this because you said it is not allowed to be changed.
    Thank you in advance.

    Christos Georgoulas has uploaded 22 CAD models & has left 85 comments.
  • Hari prasath

    Hari prasath 6 months ago

    i have problem like this force direction plz help me

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • Robert Kwiatkowski

    Robert Kwiatkowski 6 months ago

    Are holes in the shield front allowed?

    Robert Kwiatkowski has uploaded 13 CAD models & has left 13 comments.
  • David Heiny

    David Heiny 6 months ago

    Hi everyone,

    a few comments to the design requirements:
    * The shield front (the red marked area) is not allowed to be changed. So the 2500mm x 100mm shield front needs to be there without holes and flat. However if you want to add something to it on the sides, top or bottom, that is fine. Then you just have to make sure that the load areas are still correct.
    * The design needs to be symmetric since you never know where a crash happens. The load cases P1, P2 and P3 are only the "test procedure" for such a protection device.

    I hope that helps to better understand the challenge description! If you have questions or problems with the SimScale platform, please feel free to either ask here or approach the SimScale support via support@simscale.de!

    All the best from Munich,

    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hevi

    Hevi 6 months ago

    So, each force (P1/P2/P3) is a one test, so we need to do 3 FEM tests? ;)

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    Exactly!
    You should imagine these load scenarios as the maximum stresses raised by the impact of a vehicle but every time in a different point of this front shield.
    In addition a symmetrical design will ensure the validity of the model such as if the loads have been applied from the other side as well...

    So in total you test this model for six different scenarios however due to symmetry only three FEA tests need! ;D

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • jura stok

    jura stok 6 months ago

    The winner should offer complete liability protection. :)

    jura stok has uploaded 30 CAD models & has left 193 comments.
  • Jonathan

    Jonathan 6 months ago

    totally going to make mine out of cardboard.....

    Jonathan has uploaded 141 CAD models & has left 1561 comments.
  • xenofon

    xenofon 6 months ago

    How about hollow structural members? is that OK (all thicknesses >10mm) ?
    Thanks.

    xenofon has uploaded 6 CAD models & has left 7 comments.
  • Robin D

    Robin D 6 months ago

    Is there a way to turn the axes of the model in simscale? My P1 force is not horizontal but vertical, so I have to turn my axes but I don't know how.

    Robin D has uploaded 7 CAD models & has left 14 comments.
  • Leonardo Alves

    Leonardo Alves 6 months ago

    Could you please inform if the stringer can be articulated? i know that it, will not affect the norm. Please verify.

    Leonardo Alves has uploaded 15 CAD models & has left 170 comments.
  • Leonardo Alves

    Leonardo Alves 6 months ago

    Can I make assembly or the SlimScale simulates only parts form?

    Leonardo Alves has uploaded 15 CAD models & has left 170 comments.
  • David Heiny

    David Heiny 6 months ago

    @xenofon: If the minimum material feature size of 10mm is met, then that should be fine.
    @Robin: The pressure boundary condition is always applied normal onto the face where it is assigned. So there is no need to worry about the direction.
    @Leonardo: SimScale can simulate assemblies, however in this challenge, the design should only consist out of one part.

    All the best from Munich,

    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Robert Kwiatkowski

    Robert Kwiatkowski 6 months ago

    I more question about front stringer. Is 2500mm maximum allowable length? I ask because as far as I know it is not allowed that any part (especially sharp ones) stick out of outline of a car/truck.

    Robert Kwiatkowski has uploaded 13 CAD models & has left 13 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    Hi Robert,

    You are right on your observation however to me the 2500 is definitely a fixed length.
    Following the red lines from the attached sketch you can easily figure it out :)
    Regards

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 6 months ago

    Considering the aim of this challenge you might find this video interesting enough
    Enjoy ;)

    http://www.youtube.com/watch?v=C3MPKLy9qHU

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Robert Kwiatkowski

    Robert Kwiatkowski 6 months ago

    Ioannis thanks for the video link - it' really interesting.
    I ask my question because David wrote:
    * The shield front (the red marked area) is not allowed to be changed. So the 2500mm x 100mm shield front needs to be there without holes and flat. However if you want to add something to it on the sides, top or bottom, that is fine. Then you just have to make sure that the load areas are still correct.
    And the word "sides" is interesting me :)

    Robert Kwiatkowski has uploaded 13 CAD models & has left 13 comments.
  • Master3D

    Master3D 6 months ago

    I think all the entries still showing a weak spot to ensure safety protection measurement against rear collision caused by unaware drivers

    Master3D has uploaded 34 CAD models & has left 29 comments.
  • David Heiny

    David Heiny 6 months ago

    Hi Robert,

    it's kind of a tricky question. You are right, that law (depending on the country) says that the underrun protection device is not allowed to be wider than the truck itself. However we did not put a maximum width into the challenge description, so it will still be valid if you increase the width. Although considering the weight it might also be a good idea not to do it :)!

    I hope that helps and

    all the best,

    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • David Heiny

    David Heiny 6 months ago

    @Ioannis: Nice video! We should have put that into the challenge description :)!

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • niki_malchev

    niki_malchev 6 months ago

    May I receive an answer, why nearly after 30 min of cumputing I get an error mesage in the Mesh Creator proccess in the SimScale platform.

    niki_malchev has uploaded 4 CAD models & has left 7 comments.
  • David Heiny

    David Heiny 6 months ago

    Hi niki, that sounds like the machine you were using for your mesh operation ran out of memory. Maybe the mesh parameters aimed at a very fine mesh. To be sure, you can share your project with the SimScale support team via support@simscale.de . They are here to help!
    All the best from Munich,

    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • jose

    jose 5 months ago

    I had a problem with the SimScale from a Rhinoceros file.
    I saved as a .step file and this problem when I tried to uploaded it happened:
    "Your file could not be processed successfully. Please check the file and try again."
    Then I tried to save it as a .igs file. Then I had no problems to uploaded it. I could see the geometry correctly, but when I created "new mesh" no mesh show up. The program said that everything went OK, but on the window in the right nothing appears.
    I thought that I cold be a scale problem, but i have already tried to scale it into mm and meters and nothing changes.
    Did anybody have the same problems?
    Any help?

    jose has uploaded 4 CAD models & has left 6 comments.
  • David Heiny

    David Heiny 5 months ago

    Hi Jose,
    my first guess would be that you exported your CAD model without including the volume information such that it only consists out of a shell, what can be a problem for the volume mesher. Check in the export options of your CAD system for an option called something like "include solids". To be sure, it would be great if you could provide us with the model - just reach out to support@simscale.de and our engineers will take care of it!
    All the best,
    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • jose

    jose 5 months ago

    Ok, I tihnk that it was my mistake. As I read the 10mm wall thickness, I modeled open edge surfaces, thinking that later in the program that would become 10mm 3D walls.
    I'll try with real solids and see if it works.
    Thank you for the help.

    jose has uploaded 4 CAD models & has left 6 comments.
  • Robin D

    Robin D 5 months ago

    I have the same problem, but my part is a solid and made with inventor. Shared my project yesterday with simscale but haven't received an answer or solution yet

    Robin D has uploaded 7 CAD models & has left 14 comments.
  • Jack Gibbons

    Jack Gibbons 5 months ago

    I'm having a problem defining the faces for P1, P2 and P3 in my 3D model such that they can be selected individually as faces in SimScale. Currently, when I select the faces in SimScale the whole front bar gets selected. I'm using PTC Pro/E but I'm new to it so I'm unclear as how to define those areas to be independent of each other and the whole bar. If someone could let me know how that works that'd be great. Thanks!

    Jack Gibbons has uploaded 0 CAD models & has left 1 comments.
  • David Heiny

    David Heiny 5 months ago

    @Jose: No problem! Let us know if you need more help.
    @Robin: Working on it! Will get back to you as soon as possible.
    @Jack: Some users had the same problem and it turned out that both, the splitted front shield as well as the "un-splitted" front shield existed in the CAD model which led to these picking problems. Unfortunately I am the wrong guy to ask about your CAD system since I am not familiar with it. But I guess other GrabCAD members could help!
    Best, David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hari prasath

    Hari prasath 5 months ago

    @Jack Gibbons Pro/E does not have splitting option for solid. there is no other way.Better u use solidworks or other.

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • Robin D

    Robin D 5 months ago

    I wonder if some people read the whole description of the challenge, I see a lot of cutouts in the front plate, which has to be solid for at least 10mm without any cutouts.

    As the area where the pressure is located on, is a lot smaller than prescribed, the load on the underrun protection is much lower so the displacement and vonMises is a lot lower.

    p=F/A -> F=p*A with p=continous, Aprescribed>>>>Aused
    This causes wrong analysis results.

    Robin D has uploaded 7 CAD models & has left 14 comments.
  • Lalit

    Lalit 5 months ago

    Simscale is getting crashed while loading the mesh. What should I do? Please advice.

    Lalit has uploaded 19 CAD models & has left 17 comments.
  • Aimo

    Aimo 5 months ago

    @Jack Gibbons Could you make extrusions that match areas where loads are, height 0,01mm? Don't know how that affect on FEA but worth a try.

    Aimo has uploaded 7 CAD models & has left 18 comments.
  • Konrad Jakubiak

    Konrad Jakubiak 5 months ago

    Same as Latit, Sim sometimes crashes Firefox, or not showing any mesh . STP not even finishes creating mesh process. IGS takes minutes, "finished" but i cant see any mesh...

    Konrad Jakubiak has uploaded 24 CAD models & has left 93 comments.
  • Ernesto Chavez

    Ernesto Chavez 5 months ago

    I'm experiencing the same difficulties as Lalit and Konrad. I'm trying to mesh a STEP file, but about 3 minutes into the computation it stops and I get an error. I've tried this 3 times, each for a second order moderate mesh op, second order coarse mesh op, and first order mesh op, but they all stop and give me an error. I then tried running a mesh op with an IGS file, and it works except for the fact that no mesh appears whatsoever, just as Konrad said.

    Ernesto Chavez has uploaded 4 CAD models & has left 20 comments.
  • David Heiny

    David Heiny 5 months ago

    @Konrad, Ernesto, Lalit: That's most certainly due to the fact that your browser runs into the cache limit when trying to visualize the mesh. Depending on the browser you are using, there are some hints in the documentation how to increase that limit (https://docs.simscale.de/docs/content/troubleshooting.html). But to be sure, a quick email to the SimScale support and our support team will have a more detailed look at it and get back to you as soon as possible (definitely before the end of the challenge!)
    All the best from Munich,
    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • benzaoui

    benzaoui 5 months ago

    WHERE IS THE PRIVATE OPTION

    benzaoui has uploaded 7 CAD models & has left 17 comments.
  • Padmanabh Limaye

    Padmanabh Limaye 5 months ago

    I am unable to upload any files. Evenif I am trying to upload a simple image, The page says 'Processing your renderings please wait' and after sometime 'Processing your renderings is taking a while - they will appear in your project when ready'...image size is just 51kB!!

    Padmanabh Limaye has uploaded 1 CAD models & has left 3 comments.
  • Hevi

    Hevi 5 months ago

    @benzaoui I miss this option too :)

    Hevi has uploaded 36 CAD models & has left 455 comments.
  • Armin Yousefi Kanani

    Armin Yousefi Kanani 5 months ago

    Padmanabh Limaye / when you see ( processing your rendering please wait ) delete the pic and then click on process you can see the pictures are uploaded

    Armin Yousefi Kanani has uploaded 128 CAD models & has left 848 comments.
  • Padmanabh Limaye

    Padmanabh Limaye 5 months ago

    @Armin I got all uploaded later (it was just server issues then I think)

    Padmanabh Limaye has uploaded 1 CAD models & has left 3 comments.
  • Sara Sigel

    Sara Sigel 5 months ago

    @benzaoui and @hevi We implemented the all public entries wish that we received from an overwhelming group during our recent Challenges survey. While you can no longer upload private entries, you can always wait until the last day to upload if you prefer that method.
    @Padmanabh I'm glad your files were uploaded okay. When you see the 'too long' message you can hit submit and any necessary extra processing will happen in the background. Sometimes when there is a rush of uploads this happens.

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • Sara Sigel

    Sara Sigel 5 months ago

    Be sure to beat the rush and upload your entry today so there is time to get the details just right!

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • Tibor

    Tibor 5 months ago

    Can anyone know why my browser constantly crashing when I start "MESH" procedure on SimScale?

    Tibor has uploaded 146 CAD models & has left 227 comments.
  • Stefan Gales

    Stefan Gales 5 months ago

    Try Mozilla Firefox .

    Stefan Gales has uploaded 38 CAD models & has left 119 comments.
  • David Heiny

    David Heiny 5 months ago

    Dear Tibor,

    this is most probably due to the fact that your browser reaches the cache limit. As Stefan suggested, Firefox would be a first try if you are using Chrome. If that does not fix the issue, reach out to support@simscale.de - they will provide you with a solution!
    Best,
    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Konrad Jakubiak

    Konrad Jakubiak 5 months ago

    how to flip entity, because pressure is form wrong side of the face in my simulation?

    Tibor, I overcome this "no mesh generating" problem by refining my model so it hasn't like small different faces connected and this kind of rubbish i had

    Konrad Jakubiak has uploaded 24 CAD models & has left 93 comments.
  • Denis Porus

    Denis Porus 5 months ago

    Hello Everyone!
    I am new to GrabCAD and all these challenges looks great. However this one is a bit puzzling for me. So I would like to ask the jury and organizers a question.
    In the requirements there is a rule number 2 - "Use the SimScale platform to validate that your design meets the structural requirements." But a lot of competitors used different FEM software sometimes much more powerful. So here is my question - do you keep strictly to the challange rules or are they just "pro forma"? In my opinion if you allow participants not to obey the rules it might be a bit unfair toward these who obey them and they have put more effort to get their results in Simscale platform (really nice platform!).

    I ask because there would be no sense for many people like me who don't have access to high-end FEM or automatic optimization software to compete with people who play unfair....

    P.S.
    In Razor challenge there were only 42 entries but all in required format. Why here is different?

    Denis Porus has uploaded 0 CAD models & has left 1 comments.
  • Hari prasath

    Hari prasath 5 months ago

    hi Denis Porus the Winning designs will be chosen based on the rules and requirements.

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • Amit Nara

    Amit Nara 5 months ago

    Good Question Denis, Sponsor of this challenge is Sim Scale. I don't think they will consider those entries which are not done in Sim Scale.

    Amit Nara has uploaded 12 CAD models & has left 12 comments.
  • Robin D

    Robin D 5 months ago

    They will consider the designs without the Scimscale analysis. David from Scimscale told me that a while ago, because Scimscale was crashing and getting stuck while I was trying to simulate with it. I have sent 4 models in this competition, but only one simulation didn't got stuck. Nonetheless I am really impressed at the speed the Scimscale crew replies for a free user like me.

    And Denis, if you have CAD software like inventor of solid works there is a simulation tool in it. I didn't had to pay for a license cause I am a student, so if you are also a student, go to the website of Autodesk to apply.

    Robin D has uploaded 7 CAD models & has left 14 comments.
  • Aykut Dana

    Aykut Dana 5 months ago

    waiting for the resulds

    Aykut Dana has uploaded 26 CAD models & has left 331 comments.
  • David Heiny

    David Heiny 5 months ago

    Dear Aykut,

    we are working on it! Stay tuned - they'll get released soon!

    Best,

    David

    David Heiny has uploaded 1 CAD models & has left 40 comments.
  • Hari prasath

    Hari prasath 5 months ago

    8 days more for final results.............

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • Paul Mak

    Paul Mak 4 months ago

    I managed to make a design, and fully test it on SimScale and submit my design on time. I will admit, my design may not be the prettiest, and it's not the final design I had hoped for - there were lightening features I wanted to add, but that caused problems with SimScale.

    Paul Mak has uploaded 1 CAD models & has left 1 comments.
  • Hari prasath

    Hari prasath 4 months ago

    when the results will be published the time is getting closer............

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • Ernesto Chavez

    Ernesto Chavez 4 months ago

    Congrats to all the finalists!

    Ernesto Chavez has uploaded 4 CAD models & has left 20 comments.
  • Петар Трлајић

    Петар Трлајић 4 months ago

    yeah, congrats!! great job guys. :)

    Петар Трлајић has uploaded 25 CAD models & has left 764 comments.
  • Sara Sigel

    Sara Sigel 4 months ago

    Finalists are announced! We'll post the full results with details on how they performed in each requirement category by Friday this week.
    https://grabcad.com/challenges/simscale-truck-underrun-protection-challenge/results
    .
    For those new to the Challenge process, we release what we believe to be the top entries. They are listed in no particular order. Over the next few days, participants are able to voice their support or concerns. We encourage everyone following to leave a comment with their favorite or letting us know if we left a great entry out of the mix. Don't think of this as a vote - we want to connect with you on these concepts and that means more than having you submit entries it also means getting your feedback, too.

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 4 months ago

    Congrats to the Finalist of this challenge and a big thank to Ernesto Chavez and the SimScale Crew! for the kind comments on my proposal...
    I look forward for the final-final results on Friday! ;P

    Until then I can say with confidence that SimScale following all the criteria chose very carefully the finalist.

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Hari prasath

    Hari prasath 4 months ago

    some of them used other softwares........but we did the whole project in simscale only.

    Hari prasath has uploaded 49 CAD models & has left 36 comments.
  • pav_lechev

    pav_lechev 4 months ago

    Thank the organizers for their decision to choose me as one of the finalists. I congratulate all participants and finalists in this great challenge !

    pav_lechev has uploaded 19 CAD models & has left 27 comments.
  • Sara Sigel

    Sara Sigel 4 months ago

    Winners are announced! Thanks for all the time and effort you all put into this Challenge!
    http://grabcad.com/challenges/simscale-truck-underrun-protection-challenge/results

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 4 months ago

    Congratulation to all mates of this challenge!!! Looking forward for similar Challenges!!! nice job David Steinweg and all the rest!!!

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 4 months ago

    @Sara... Can you please check once more the results it is a bit odd that David is coming first with a design rank 2 and Alex with design rank 1 is coming second
    Do I miss something? ;P (Most probably! ;))
    ...And another point is that the Allowed maximum Von Mises stress for the FEA analysis were 355 MPa. I can see that at least 2 models produced higher stresses. How exactly did they pass the stiffness test?!
    However I am sure that you have a good explanation and therefore I don't worry at all!!!
    Cheers!

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Ernesto Chavez

    Ernesto Chavez 4 months ago

    I agree with Ioannis. I find it odd that some of the designs have stresses in some load cases that are higher than the 355 MPa max allowed von Mises stress stated by SimScale. All in all though, congrats to all the finalists and winners! It was an entertaining challenge.

    Ernesto Chavez has uploaded 4 CAD models & has left 20 comments.
  • Sara Sigel

    Sara Sigel 4 months ago

    @Ioannis Good questions. Design was only one element and the least weighted in the jury's decision. Weight and stiffness were higher factors. I'll double check all stress test data and get back to you here.

    Sara Sigel has uploaded 1 CAD models & has left 1884 comments.
  • Ioannis Skarlatakis

    Ioannis Skarlatakis 4 months ago

    Ooooh! I seeeeee! the design rank was regarding the aesthetic now it makes sense!!!
    it was a bit confusing or at least I confused... just a bit! ;P

    Thanks Sara!
    Looking forward!

    Ioannis Skarlatakis has uploaded 24 CAD models & has left 467 comments.
  • Robin D

    Robin D 4 months ago

    Indeed I agree with Ionnis, thought that the allowed max stress was 355MPa.
    And I don't get why BJ's model has designrank 7 and mine 9 while a quite simular model has the first place

    Robin D has uploaded 7 CAD models & has left 14 comments.
  • Arek

    Arek 4 months ago

    .

    Arek has uploaded 6 CAD models & has left 5 comments.
  • ibrahim

    ibrahim 4 months ago

    Congrats to all finalists and winners, enjoying challenge! looking forward for new ones..

    ibrahim has uploaded 6 CAD models & has left 6 comments.
  • bj

    bj 4 months ago

    Its flattering so many winners got inspired by my model SimScale Truck Underrun Protection Challenge
    Oh well..

    bj has uploaded 53 CAD models & has left 126 comments.
  • Alex Lewis

    Alex Lewis 4 months ago

    @loannis/RobbinD If you look through my model files you'll see screen shots of where the loads in my model were greater the 355MPa. They occur in two singulatirities around the bolt holts, effects of the limited constraints and a too coarse mesh in those areas.

    Alex Lewis has uploaded 1 CAD models & has left 6 comments.
  • Robert Kwiatkowski

    Robert Kwiatkowski 4 months ago

    Congrats for all the finalist! Really great job!
    It was a great things to watch how all designs were getting better and better.

    Robert Kwiatkowski has uploaded 13 CAD models & has left 13 comments.
  • Jonathan

    Jonathan 4 months ago

    congratulations to all finalists and winners, they all look like great, solid designs! sadly, I had to trade this challenge for another....until next time.

    Jonathan has uploaded 141 CAD models & has left 1561 comments.
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