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3D Printing Oxygen Valves for Low Resource Settings
The Goal of this Challenge is to design a life-saving medical device that can be 3D printed out of acrylonitrile
butadiene styrene (ABS) thermoplastic using fused deposition modeling (FDM) desktop style printers.
To win, create a 3D printable oxygen splitter that allows you to independently control oxygen flow rates (in liters per minute) for two patients sharing one oxygen tank who are receiving supplemental oxygen via nasal cannulas. This will help conserve oxygen use, which is a precious commodity in low-resource settings.
Our aim is to support those who work in the worst context around the globe to save life's of the most vulnerable. The winning designs will be available for an unlimited humanitarian usage of the design solutions.
Your entry must include:
• Preferably designed in OpenSCAD (www.openscad.org)
• Rendering of your design preferred
• Videos of the printed objects being used preferred
• STL file formats
Technical requirements:
Printed entirely out of ABS on a desktop FDM (range 20 – 250 microns, ex. Cube, Makerbot, Lulzbot) on a heated or non-heated 15 x 15 cm print bed
No post-processing of printed object (i.e., no support material, filing or sanding)
Preferably designed in OpenSCAD (www.openscad.org) to allow free customizability
Judging criteria:
Judging criteria will be based on achievement of accomplishing criteria listed above, including:
1. Printability: how well it prints across a range of desktop printers and material colors
2. Functionality: how well it works, how easy it is to use, can it fit a range of oxygen tank outlet valves
3. Cost: the lower, the better; consider power usage and material costs
ENTERING THE COMPETITION The Challenge is open to everyone except employees and families of GrabCAD and the Sponsor. Multiple entries are welcome. Team entries are welcome. By entering the Challenge you: 1. Accept the official GrabCAD Challenges Terms & Conditions. 2. Agree to be bound by the decisions of the judges (Jury). 3. Warrant that you are eligible to participate. 4. Warrant that the submission is your original work. 5. Warrant, to the best of your knowledge, your work is not, and has not been in production or otherwise previously published or exhibited. 6. Warrant neither the work nor its use infringes the intellectual property rights (whether a patent, utility model, functional design right, aesthetic design right, trademark, copyright or any other intellectual property right) of any other person. 7. Warrant participation shall not constitute employment, assignment or offer of employment or assignment. 8. Are not entitled to any compensation or reimbursement for any costs. 9. Agree the Sponsor and GrabCAD have the right to promote all entries. If you think an entry may infringe on existing copyrighted materials, please email challenges@grabcad.com
SUBMITTING AN ENTRY
Only entries uploaded to GrabCAD through the "Submit entry" button on this Challenge page will be considered an entry. Only public entries are eligible.
We encourage teams to use GrabCAD Workbench for developing their entries.
Entries are automatically given the tag "oxygenvalvesplitter" when uploading to GrabCAD. Please do not edit or delete this tag. Only entries with valid tag will participate in the Challenge.
AWARDING THE WINNERS 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. All judging decisions are final. All winners will be contacted by the GrabCAD staff to get their contact information and any other information needed to get the prize to them. Payment of cash awards is made through PayPal. All team awards will be transferred to the member who entered the Challenge. We will release the finalists before the announcement of the winners to give the Community an opportunity to share their favorites in the comments, discuss concerns, and allow time for any testing or analysis by the Jury. The Jury will take the feedback into consideration when picking the winners. Winning designs will be chosen based on the Rules and Requirements. - Entry deadline is January 7th, 2016 (11:59pm UTC). - The finalists will be announced by February 2nd, 2016. - The winners will be announced by February 11th, 2016. Void where prohibited.
SPEC REFINEMENT We want to make sure that you have all of the information that you need to tackle the challenge. As such, in the first week of a challenge we may refine the specifications or offer clarifications based on member feedback. Please ask any questions that you have!
Prize pool of $3,400, 3D4MD and GrabCAD Swag for top 10 places!
$1,500 + 3D4MD Swag + GrabCAD Swag
$1000 + 3D4MD Swag + GrabCAD Swag
$500 + 3D4MD Swag + GrabCAD Swag
$300 + 3D4MD Swag + GrabCAD Swag
$100 + 3D4MD Swag + GrabCAD Swag
3D4MD Swag + GrabCAD Swag
The jury consists of experts from 3D4MD, Stratasys and GrabCAD.
3D4MD makes 3D printable medical supplies to deliver healthcare in the most challenging places to those who need it the most. www.3D4MD.com
Stratasys Medical Solutions is building solutions that accelerate innovation, improve medical care, and facilitate the adoption of new medical technology. 3D printing solutions include pre-surgical planning to improve patient outcomes, create training and education anatomical models, and real-patient image derived models for device testing to improve research and development. Stratasys Medical Solutions
Andrzej Stewart
Gus Douboulidis
Adam Arabian
Matt Ratto
Sheyna Gifford
David Ott
Julielynn Wong
Scott Rader
Michael Gaisford
Howard Rhett
Ben EwingHave an awesome idea for this competition? Want to win cool prizes? Sign-up now to upload your entries.
If you don't receive the email within an hour (and you've checked your Spam folder), email us as confirmation@grabcad.com
104 comments
Tamas Jager over 9 years ago
Don't make me laugh with scad file format. Please suggest us an effective 3D program with parametric programming! Or share a link where we could convert our Solidworks, ProE, SolidEdge, Catia ect.. files to OpenScad format!
Don B over 9 years ago
I can't get into the 3D4MD links provided just above...bad links
James Sawyer over 9 years ago
post-processing : Dose this include assembly? Can a single component be printed in two parts and fastened together?
James Sawyer over 9 years ago
I have problems making prints that are water tight without coating. How will it hold gas at pressure. Note: I use PLA and a beginner. Is ABS that much better?
Julielynn Wong over 9 years ago
JT: We prefer if entrants use OpenSCAD because it is freely accessible and allows minimally trained personnel to customize 3D models because the device will have to be adjusted to fit a range of oxygen tank outlet valve sizes. We are open to entrants using any 3D modelling software but keep in mind that users in the developing world may not have the training or resources to use proprietary software programs to adjust the fitting of this device. This would impact the device's utility in a low-resource setting. Additional feedback is always welcome.
Julielynn Wong over 9 years ago
JS: Yes, you can print this device in two parts and assemble the device afterwards. Ideally, it wouldn't require any additional non-3D printed items (i.e., metal bolts) for assembly because these items may not be available in a low-resource setting.
ABS is preferred material because it is much more robust than PLA. PLA is biodegradeable (i.e., less durable) and tends to expand when it absorbs water.
Julielynn Wong over 9 years ago
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Terry over 9 years ago
Hi, what is the tank delivery pressure to the splitter and what is the desired range of flow rates to patient, also, what is the OD, ID and Length of the delivery tube to patient, is this size consistent the world over? How critical is the determined flow rate? Within a couple of litres per minute? or perfectly accurate
Julielynn Wong over 9 years ago
T: The desired range of flow rates for standard nasal cannula oxygen tubing ranges from 1 - 5 liters per minute. The flow rate should be adjustable in 1 liter per minute increments (i.e., 1, 2, 3, 4, 5 L/min, etc.,). I'm working on obtaining the other information you requested...
Terry over 9 years ago
Cheers
Terry over 9 years ago
What orientation does the outlet come out from the oxygen regulator, i.e. vertical or horizontal?
Julielynn Wong over 9 years ago
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Steve Sargent over 9 years ago
Hello, I have a few couple questions. I submitted a design, but I don't know scad, nor have time to learn it now. Can you please suggest other formats that may be useful to you? Or suggest a way to convert Solidworks to Scad?
Steve Sargent over 9 years ago
Also, since thread details need to be modeled for correct printing, could you tell us one or two of the oxygen valves that you might be using? It makes it easier on us designers to have as much info as possible upfront, more than just "fit multiple valves"
Steve Sargent over 9 years ago
Sorry I just thought, is our part supposed to be able to measure the changing output? If this is the case, designing a one piece FDM part may prove difficult.
Julielynn Wong over 9 years ago
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James Matthew over 9 years ago
Are there any concerns about using ABS in oxygen service? Can it be cleaned for oxygen? Just curious.
SAMET AY over 9 years ago
This's very good component design for medicine sector. Congraulations !
Steve Sargent over 9 years ago
Thank you Julielynn!
Steve Sargent over 9 years ago
Bringing oxygen to MY HOME COUNTRY! Ayiti Sa Kap Fet!!!
Julielynn Wong over 9 years ago
This comment was removed
jamie over 9 years ago
If the filter is printed in separate parts can it be glued together or does it have to clip together? My issue with clipping together is getting an air tight seal?
Paul Mak over 9 years ago
So our device attaches to a piece of tubing, or directly to the oxygen tank? If we connect to the tank, are we making the threaded fitting? And by tank I'm assuming we're on the low pressure side of the regulator.
Julielynn Wong over 9 years ago
Jamie: Ideally, it would not require glue because we can't ensure glue will be available in a low-resource setting.
Julielynn Wong over 9 years ago
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AC over 9 years ago
Note to self: Screw threads smaller than 1/4-20 (especially machine screw thread profiles) will not adequately 3d print. I have to come up with something custom.
Catalin over 9 years ago
What dimensions should we use for in and out?(diameter)
Achmad Silmi over 9 years ago
It should be easier if inlet port of standard oxygen mask and pipe dimension is given.
James Matthew over 9 years ago
I agree with Achmad Silmi and others - the diameter of tubing seems difficult to find.
J. F. Gomez over 9 years ago
@ Julielynn Wong: Thanks for changing the requirement to a preference as far as OpenSCAD is concerned. I also suspect that many people in the GC community would be more than happy to assist in making future changes should your local assets around the world be lacking access to other 3D design suites. Kind of like a "Designers Without Borders" humanitarian effort.
Terry over 9 years ago
I concur with J F Gomez comment, any required changes would not take long and for me, this is not about winning a prize but contributing to a worthwhile cause
qwave qwaveq over 9 years ago
I found something about the tubing diameter on a catalog where it says 2.8 x 4 mm (internal and external). I don't know if this is the only one existing but i did't fount anything else. You can find this information here at page 11 under "nasal oxygen cannula" : http://www.dina-hitex.com/dokumenty/ceniky/PLASTY_EN.pdf
I hope it helped :D
AC over 9 years ago
Note to self: you cannot 3d print features that are less than .030" in thickness with crisp resolution.
Hevi over 9 years ago
1.What's the OXYGEN pressure that we are operating in our splitter?
2.Do you plan 3D print every model and test it before choosing the winner?
jamie over 9 years ago
im still confused about this project - how on earth can you 3d print something in ABS and keep an airtight seal without using any other components - like glue or O rings etc. (rubber seals). No matter how hard you try air will leak from a 3d print - so how can you measure the exact amount of oxygen restricted by the printed device?????
Hevi over 9 years ago
jamie +1 ....I have the same doubts about this...
qwave qwaveq over 9 years ago
i'm about to load my project wich can bypass that problem. It is a bit tricky but it is possible.
Hevi over 9 years ago
Another, so we can use plastic tubes? Tell us - we can or we can not do this.
Robert King over 9 years ago
@Julielynn Wong what kind of finite adjustments should there be to flow rate? Is the minimum an increment of 1 L/min? What is the maximum flow rate that is tolerable?
Robert King over 9 years ago
Also, what kind of flow velocities are coming out of a tank?
Don B over 9 years ago
I can only imagine that out in the field they will be carrying tanks that are mounted on the back of a truck. Just try and imagine in your mind what kind of hurdles the crew would encounter. Imagine all the negative roadblocks that would stop them from saving a life. And while you are at it, go ahead and imagine the smile of a new mother holding her newborn baby and being helped by the crew you designed stuff for.... blessings
Hevi over 9 years ago
@Don - Ok you are right but like you said, they will have tanks on the back of a truck and what about 3d printers that they are supposted to use? :) They will print these splitters somewhere else and they can check 3d printed splitters before mounting on tanks etc. So there is a place where is 3d printer, they can 3d print, maybe they have plastic tubes there etc
We need to know what we can use; they need to decide - we can use only 3D printed things or maybe we can use something extra, if yes - tell us: what we can use?
Sam Savage over 9 years ago
I'm excited about this project, the concept of a pop up hospital in remote parts of the world using 3d printing to get the equipment needed as fast as possible is very exciting. This project is just one pixel of the larger picture! :)
Don B over 9 years ago
@Hevi.... Well, I went to the website for the company who will be out in the field. I see it as a small team of med techs trained in 3D tech also driving up in a truck with med supplies in the back. They assess the village of what medical needs they are deficient of and start up the generator. I'm thinking we can help those in need big time here. Just by donating our designs.
Gert Kaasik over 9 years ago
Should it connect to the metal oxygen tank outlet valves or to a tubing?
Gergo Graf over 9 years ago
Sorry to bother you guys but I have to post it here as well in case it will get deleted from the entry comment.
The entry: https://grabcad.com/library/valve-of-oxygen-ergonomic-control-1
My entry: O2 Splitter Valve
My comment:
Does it look familial to anyone? Just because you download my entry, modify it a bit and upload it as your own it does not make it your own concept. This is disgrace.
Don B over 9 years ago
Good Point Gergo. I've seen a few challenges that the judges can tell by the entry dates who copied who. I'm believing these judges are wise enough to do the right thing.
Hevi over 9 years ago
@Gergo - I had same situation like you have and one more time I will say this - bring back "private entries" :)
Julielynn Wong over 9 years ago
Greetings all entrants! Fantastic work. According to our friends overseas, it would be very helpful for staff to be able to adjust the flow rates in 1 L/min intervals. Can you think of any 3D printable design features so a worker could tell how much the flow rate is for each patient?
Steve Trutanich over 9 years ago
Finally. Figured it out. See you guys in a few days. Sorry, Solidworks only.
Steve Trutanich over 9 years ago
Juylilynn, we need tank velocities. Otherwise our diameters will be arbitrary, but then again, as you said, with open scad can be tailored.
Don B over 9 years ago
@ Ms. Wong. I think for anybody to use ABS plastic and calibrate it with L/min intervals would probably involve more than the average designer here. ABS plastic is not as solid as it looks. Water can diffuse through it. To seal it would take some acetone based solution that probably would not do well with oxygen.
There are a lot of variables involved with calibrations. BUT, guess what? I think we can overcome these obstacles and at least try and help those in need. You all might need to print your project out and do a test run. Take it to a local hospital or college and ask them to set up a test stand.
People need these things. Or why would Ms. Wong be here asking for help?
Steve Trutanich over 9 years ago
@Ms. Wong. Must the cannula be kink resistant?
Julielynn Wong over 9 years ago
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mohamed laouridi over 9 years ago
hey just i have a question plz , are we have to include the flow meter with the design ???!
Steve Trutanich over 9 years ago
I'll assume the receiving end of the splitter is attached to an oxygen tube as you just described.
Julielynn Wong over 9 years ago
You don't have to 3D print the flow meter. Let's say you have two patients, A who needs 2 L/min and B who needs 4 L/min. According to one expert, you would set the flow regulator to 6 L/min, attach the 3D printed oxygen splitter, and attach the two sets of nasal cannula tubing. However, the splitter needs to be able to regulate the flow for each patient so A received 2 L/min and B receives 4 L/min. I hope this helps.
Steve Trutanich over 9 years ago
Since the regulator can adjust between a number of liters/min, it would be much more convenient, and far less confusing to the medical personnel, if the 3D printed splitter was adjustable as a percentage of the regulators output. Unless of course, the regulator was always set to 6 l/min.
Julielynn Wong over 9 years ago
Thank you for raising this point. The oxygen regulator is not always set to 6 L/min.
Gary Marriott over 9 years ago
An observation two:-
The challenge image is not I think of a nasal cannula but of a simple face mask. They both work similarly but the cannula is a total loss system where gas is always flowing weather the patient is breathing in or out. Whereas, a face mask can be fitted with a rebreather bag such that the approximate 50% loss of the cannula can I think be partly recovered.
Thus since In a low-resource setting I would assume that saving Oxygen is a priority it would seem inappropriate to suggest cannulae, unless that is the challenge is to build a system to regulate flow such that it is suppressed upon exhalation.
Obviously I am not a physician, but if I were to enter I would propose that instead of a constant flow rate a demand system, be a better solution.
AC over 9 years ago
Everyone is a salesman.
Mart Berghs over 9 years ago
Eeuhmm, there is something like "CRUSH RESISTANT" oxygen supply tubing.
Blair Hollshwandner over 9 years ago
Gary Marriott is correct about the picture. It depicts a standard adult mask which are usually only used when conservation is not a priority. A standard high flow adult cannula is more efficient. I wish I had known about this challenge sooner. I work for a medical respiratory manufacturer. We design and build everything from oxygen flowmeters to oxygen conservers and portable oxygen concentrators.
Julielynn Wong over 9 years ago
This comment was removed
Luis Arias 3D CAD over 9 years ago
Good luck for every one!
Donald Greenley over 9 years ago
Good afternoon! I have already submitted a design, I am wondering if now that the deadline has been met if I am able still to upload additional images? I have been weighed down with my 9-5 and haven't yet been able to finalize and upload a video of the device functioning. What are the rules there?
REDA DJABRI over 9 years ago
Hi Donald,
I accept it because the ultimate goal is humanitarian
Ben Ewing over 9 years ago
My apologies for not seeing your question, Donald Greenley. We like the projects to be finalized by the deadline as judges begin to review them after the deadline. If there are additional renderings that you feel help explain your design, you are welcome to upload them but keep in mind that the judges may have already reviewed your entry. We do not accept any changes to CAD data after he deadline, however.
Ben Ewing over 9 years ago
In regards to the finalist announcement, we are going to need to postpone the announcement until February 2nd. The judges are currently working to 3D print all of the designs in order to thoroughly review the entries. My apologies for the delay!
Donald Greenley over 9 years ago
Thanks, Ben. I appreciate the communication. I went ahead and added an image (not a video) of the printed component as well as a document outlining strengths, function etc. It was the "script" for the video but as I had not gotten a reply I assumed that would be less frowned upon than a video. There were no changes to the CAD data. Bummer on the delay, but being thorough is key in engineering. I am a firm believer in that haste makes waste!
REDA DJABRI over 9 years ago
Result soon....Suspens!
benjamin benji over 9 years ago
been waiting for results since this morning SA time?
Ben Ewing over 9 years ago
I'm happy to announce the finalists for the Oxygen Valve Splitter Challenge: https://grabcad.com/challenges/oxygen-valve-splitter/results! Next the judges will be taking an in-depth look at all of the judging criteria and how each entrant performed in those areas. Congratulations to the finalists and to all of the entrants!
Fernando Franco over 9 years ago
I would like if possible to receive feedback from you regarding my project? We are working to enable the use in hospitals in my city and it would be important to know what can be improved after the evaluation of the jury.
Congratulations to the finalists and thanks to the organizers.
Donald Greenley over 9 years ago
I again find myself rather disappointed with another GrabCad challenge. In both cases I have seen selections made that directly go against set judging criteria. I should clarify that I am not upset because I am not selected as a finalist, I saw plenty of projects that surpassed my own, my upset comes strictly from failure to adhere to design criteria when judging. If that is the case then what purpose does the initial criteria serve? One of the quotes next to a finalist is "issue controlling flow", which is one of the primary functions of these devices! I come from the automotive industry where failure to adhere to certain criteria can be very costly, so maybe I am being critical, but I still have to question the thought there. Beyond that I would be inclined to question the durability of some of the selected projects (low resource environments will demand a tough piece) and based off of images would question whether or not they were printed with set design parameters.
Either way, nice job finalists! I hope I see one(or more) of these in the field someday!
Judges - Stick to the criteria!
Juan Callón over 9 years ago
Very happy for being selected. Congrats to everyone! :-)
Fernando Franco over 9 years ago
I can not say I'm disappointed, but I truly believe that Donald has a good point on the issue of criteria.
REDA DJABRI over 9 years ago
Hi Ben,
My "O CONNECTOR" Fills the criteria perfectly with infinite precision and a generous and beautiful design to see. A thought also for Donald ;)
I am very disappointed ... pity for the projects that I started it will take me time to get it
Do not tell me it was not you who chose here too
regards
Reda
Donald Greenley over 9 years ago
Imprenta3D is a good example of criteria failure. I cannot see from the design how you would be able to "independently control the flow" of oxygen to each individual patient attached to that feed. The flow, from what I am seeing, would be reduced to both patients.
Juan Callón over 9 years ago
Donald, you are right, you can't control the flow independently for each patient, just regulates or stops the flow.
What I understood when I made the design was that the mechanism could regulate the total oxigen flow independently from other parts. But maybe you are right and my design shouldn't be there.
Despite all, good luck for the rest of selected ones, very nice, simple and good designs which could help to save lifes.
Donald Greenley over 9 years ago
I also read "unique one piece design", and the designer specifically calls it out as a 3 part design... Were these reviewed at all?
REDA DJABRI over 9 years ago
Donald , you are right one unique piece ..... !!!! Incredible chose
Adriano Ordoz Barissa over 9 years ago
Adriano Ordoz Barissa about 3 hours ago
congratulations to all the finalists, after all had your job to be on that list. My favorite is https://grabcad.com/library/o2-regulator-1;, anyway I bet and worked in a very similar concept Valve splitter - by Adriano Ordoz Barissa
Donald Greenley over 9 years ago
With respect, I see your point in regard to personal understanding, but from the release of the challenge it specified the device would have to independently control the flow to each patient's feed. Failure to do that should drop the project out. The decision has already been made as to which projects made the final cut, but they asked for feedback and I truly believe there is a failure here on the judges part to follow their own design criteria and as this is the second time I have witnessed this with a GrabCad challenge I am pretty upset about it. Those slots should, at minimum, be filled with projects that met ALL of the criteria, even if they have other issues. Take "Prinatable Oxygen Splitter" by Ludwig Kristiansson, which in my perspective is easily a TOP 5 design. Fast to print, works well (maybe a little refinement to help any potential leaks), incorporated a method to locate the splitter (top loop for hanging) and allows independent control. My only critique on this would be to remove the steps and replace with a progressive "obround" for finite control rather than "step settings". He corrected this a bit with his second design (happy to see made the cut) but now there are multiple components to be lost, release from the build plate when printing, etc. Plus there is no central location for the adjustment which can make a difference if an emergency were to arise... "Wheres the cut off!?" (digs through sheets to chase the hose). Also, more spots for an accidental disconnect.
Ben Ewing over 9 years ago
Hi Donald and all, we really appreciate your feedback on the judging process. It is something that we are always working to improve and we will definitely keep everyone's suggestions in mind for future challenges. One of the requirements for the challenge was that there was no support material necessary for the design and in some cases, that disqualified certain entries. I can assure you for the winner selections, the judges will be thorough in examining the entries to ensure that they adhere to the judging criteria and to the technical specifications outlined. Again, thank you all for your feedback and for your passion for design, engineering and GrabCAD Challenges.
Fernando Franco over 9 years ago
Hello Ben,
Sorry but frankly, now I'm really disappointed.
Something we have learned in the early days of the college, in my case, many years ago :), is to respect the project premises, especially in products related to the medical field. Another thing we learned early is that regardless of the rules of a company (in this case a challenge), if critical errors are detected the work should be revised immediately, not in the future, at the risk of getting nothing but failure, if not done .
I will not criticize any individual design, but would like to mention at least one practical and critical example, which is the device's ability to receive various diameters of cannulas. When we were in the research stage of our project we make a visit to the hospital of UNICAMP here in Campinas, one of the largest university hospitals in Brazil, we spoke to some nurses on the project and on the related difficulties they face in their daily lives and we found that they were dealing with at least three models of cannulas, each with a different diameter (ranging from 1/4 "to 1/2") and sometimes they had to "adapt" the connections to try to make the system work . Well, if it occurs in a large hospital, imagine in the "worst context around the globe", so the premise "2. Functionality ... can it fit the range of oxygen tank outlet valves," that none of the chosen designs considers.
In our view, the worse the environment of use, the lower will be the availability of standard items, and therefore, will be needed more practical and universal solution.
Please do not get me wrong, I am a designer by academic training and career and I know how important the qualities of beauty and innovation, but for this problem specifically the functionality that is the fundamental point.
My suggestion, review your premises of choice.
Fernando Franco over 9 years ago
Only one additional comment to be fair: Among the chosen designs, the Sean Buxton's design (Custom Bleed Valve and Flow Splitter) considers the possibility of different diameters of cannulas, however the three must have the same diameter which limits the solution. But the concept adopted (bleeding) is frontally opposed to the need to "help keep oxygen use, Which is a precious commodity in low-resource settings.".
Sean Buxton over 9 years ago
Good work everyone! I'm a big fan of the devices that simply pinch the tubing to control the oxygen flow, I think its great from a simplicity and anti-leak perspective. Has anyone actually done the math to know how much you would have to restrict each tube to achieve desired flow rates in 1 L/min increments?
I attempted to do the math with an analogous electrical system, but the math is really tough. I was thinking the pinching element would work like a resistor in an electrical system, but struggled to describe how the rotameter and regulator on the oxygen tank would work in the system. Not sure if that would be analogous to a constant voltage or current system. I think figuring out that issue and how to communicate the appropriate "pinch" settings to the user would be the big step in actually making something that works. Figured I'd throw that out there to all the smart people on GrabCAD to chew on.
Best of luck to all the other finalists!
Adams Jasmine over 9 years ago
Hye all grabcad member,
especially to participate challenge.
From my opinion, participate should always bear in mind that jury's decision is conclusive. Judges also have right to choose any model based on standard.
To prevent issue of duplicating design, better submit entry last minute before deadline or submit rendering only before CAD data.
Most of 3d printing challenge, at the first place they focus on low cost and simple model for easy printing and criteria is second aspect they looking for.
Entry for this challenge have great design and concept.
So, goodluck to all finalist!
Adams Jasmine over 9 years ago
One more thing, as mention before judges already print all model before selected the finalist. Maybe they are best from the best entry.
Donald Greenley over 9 years ago
Well then I would have submitted a simple cube. That would not meet the criteria but it would print very easily! One of the ideas of Engineering is to find innovative SOLUTIONS to PROBLEMS. If the device cannot do what it needs to there is no solution to the problem at hand. I think forcing us to adhere to criteria the judges are not required to use for judging is quite simply a crock! This has discouraged me from wanting to participate in any other challenges. And the above response (6 comments upward) did not really help. I honestly don't think they put as much effort into judging as we all have into designing these items...
Ben Ewing over 9 years ago
Hi Donald, I can assure you that the judges do pay attention to the judging criteria. I'm sorry that you feel that they did not do a great job adhering to them. The judges will release more information about their selections when the winners are announced in several days. I hope that the winner selection and additional information will help alleviate some of your concerns with the process. As always, if you'd like to discuss the challenge process or voice concerns with how challenges in general are run, please email me at ben@grabcad!
REDA DJABRI over 9 years ago
Hello Ben All,
I notice in your there over a model where we do not need a 3D printer to manufacture, simply take a stick and dug ... I wonder if the jury has encouraged new members or students .. this is a health equipment wake up ... we're not on a social network like the guys here. And credibility of GrabCAD ?
Thank you for review your selection ....
Regards
Reda
Andrzej Stewart over 9 years ago
Perhaps I can give a bit of insight into the preliminary judging we used at HI-SEAS.
First, a bit of background. Sheyna Gifford and I are crewmembers on a year-long NASA-funded Mars mission simulation. We have limited supplies here: a limited amount of ABS, and a single Lulzbot AO-101 for printing. Due to the parameters of the mission, we're isolated, and can't readily obtain more ABS or another printer at a moment's notice. Additionally, before the mission, none of the crewmembers had any 3D printing experience - we've been learning over the last five months while we've been here. So, in a sense, we're a simulation of what the real designs will have to go through - manufacture from limited supplies, by personnel with limited means and training.
We had 130 eligible entries to evaluate in preliminary judging, and were instructed to narrow down to 20 designs. We looked at every design submitted, taking time to understand how each one worked. The first thing we did here at the HI-SEAS hab was look at whether the design fit the judging criteria: Could it split flow? Could it control each flow independently? Note that, for accommodating multiple tube sizes, we allowed for the model to be scaled - the SCAD format allows this to be done very easily. If the design did these things, then we next evaluated it on the ability to print without support material.
Based on those criteria alone, we were able to get down to a selection of 24 designs. From those, we did a second round of evaluation to narrow down to 20, based on amount of material used and effectiveness of the design. Note though, that this was 24 designs, not 24 designers...some designers had multiple designs that fulfilled the requirements. Ultimately, 16 *designers* were chosen. Their 16 designs are all printable, and I feel that's a good first step - if the design is impossible to manufacture, it doesn't matter what else it's designed to do.
From here, we're printing all 16 finalists here in the dome. We'll be judging how well each design prints, how durable it is, and how well it performs the intended functions. We've got our eighth print on the bed as I type this. We've already had a few break under light handling - for me, that's going to be a disqualifier, as you can't rely on something that'll break easily in a medical emergency.
A bit of feedback, please take this constructively...I was surprised by how few designs were submitted with photographs of an actual printed piece. Those designs that did tended to be viewed favorably by us during preliminary judging, as those photos proved printability. Testing and identification of problems is an important part of the engineering design cycle - I believe the designers printing out and testing their own designs helps them identify flaws, allowing for improvement.
Donald Greenley over 9 years ago
Andrzej. Thank you for the feedback. I must admit my initial disappointment has caused me to lose interest in the challenge (or future challenges), but I do appreciate you taking the time!
Many Thanks,
Mark Mellors over 9 years ago
To try add a little more science to the assessment of the designs, I've tried to print out all the designs and do some quantative testing of their flow performance, using a flow meter. I've commented on all the individual design pages with their results, including the page of my 'slide rule' design, which I much prefer over the 'very simple' design of mine that was selected as a finalist. You can see the detail the relevant pages but in summary: all of the designs that try to seal between two printed parts leak significantly (>30%). Many of the designs with 'gas wetted' printed components also leak a fair amount (>10%). The splitter of the 'OxygenRegulator' design had the best splitting (sealing) performance. The restrictor of that design was also pretty good. The restrictors of my 'slide-rule' design, 'oxygenvalvesplitter' and 'Improved oxygen splitter' all work very similarly and well, although mine is the only design that gave a useful indication of the setting. The flow meter of the 'oxygenvalvesplitter' design worked incredibly well and was the only design that would actually allow you to set a repeatable flow rate in varying conditions.
It also worth mentioning that its impossible to ‘independently’ vary the flow rate to the two outputs. If it is being fed by a single flow regulator, then restricting the flow to one patient must increase the flow to the other, and my measurements reflected that. Separate adjustment mechanisms may give users the impression of independence, which could lead to mistakes (increase supply to patient A, patient B’s supply goes down, unnoticed).
Testing photos:
https://www.dropbox.com/s/ev053dr60keoevk/all%20designs.jpg?dl=0
https://www.dropbox.com/s/ojoxf6k62b1k8bt/test%20equipment.jpg?dl=0
https://www.dropbox.com/s/ufjd4hrmgn17g6m/slide-ruled.jpg?dl=0
https://www.dropbox.com/s/8zzibbj62gbazda/oxygenvalvesplitter-2a.jpg?dl=0
Ben Ewing over 9 years ago
We are happy to announce the winners: https://grabcad.com/challenges/oxygen-valve-splitter/results! Thanks to everyone who participated! There were so many unique solutions for this fun, impactful challenge. We believe these finalists are the best solutions. To pick the winners the judges tested each of the finalists based on the judging criteria and rated the 10 winners based on Cost (1-6), Printability (1-6) and Functionality (1-11). Congrats to the winners and all of the finalists!
Ben Ewing over 9 years ago
Also, if you're interested in a small glimpse into the judging process, take a look at our recent blog post: http://blog.grabcad.com/blog/2016/02/09/evaluating-3d-printed-parts/.
J. F. Gomez over 9 years ago
Thank you GrabCad and 3D4MD teams for your consideration. Here's wishing you all success in this worthwhile endeavor.
Juan Callón over 9 years ago
Congratulations to the winners, nice jobs!
Anton Alveflo over 9 years ago
Thank you Imprenta3D! I would also like to thank GrabCad, 3D4MD and Stratasys for this opportunity.
Fernando Franco over 9 years ago
My congrats to the winner, good job!
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