Once upon a time, I was a huge proponent of prototyping medical devices as soon as possible. Today, I’m a little more hesitant. Don’t mishear me–prototypes of your medical device can certainly be extremely valuable. However, I think it is VERY important to be clear about what you hope to learn from the prototype. Equally important, it is VERY important to understand what the prototype can not do. In other words, know what decisions can be made based on the type of prototype you have.
Let me expand a little.
Several months ago, we were initiating a medical device design and development project. We had some product designs sketched and started to narrow the list down to just a few concepts. Once narrowed, the design resource offered to “grow” some 3D prototypes. Within a few days, we had 3D concepts in our hands to better evaluate some of the design ideas we had been discussing a viewing on screen. Having the prototypes in hand was helpful. We were able to better evaluate features and aspects of the product design. We were able to play around with component interfaces and get a feel for how the user would interact with the device. We made a few tweaks but soon, we decided to proceed with cutting steel for injection mold tooling.
Tooling was to take ~10 weeks. We made progress on other parts of the product design while we patiently waited for those first articles. When the tooling was completed, first articles were provided soon after. We were all anxious to evaluate these parts. When we did, the design presented to us via concept sketches and 3D prototypes did not seem to translate into injection molded parts. What happened? Why not? The design resource offered that the prototypes might not have been an ideal representation of the injection mold parts. They also stated that they could make a few minor modifications to fix some of the design concerns. Another round of prototypes and another round of discussions.
Why was this round of 3D prototypes any different? I guess we trusted that the designers would make the design right.
Several more weeks were necessary to modify the tools. And eventually another round of first articles. Which once again, failed to hit the mark we needed with the product design. Frustrated began to mount. And I kind of scratched my head. What went wrong? Why were the prototypes so bad at representing the product design?
Then it hit me. Medical device prototypes are not the end all be all. Prototypes have limitations. You have to understand what the 3D prototype can and can not do for your design efforts. I learned that SLA-type of prototypes is not a real approximation of what you might expect from injection mold tooling.
When you get prototypes for your next project, take a few moments to truly understand what these prototypes can tell you. What exactly can you learn? More importantly, do not fall into the trap that a 3D prototype can answer all your design questions. It’s a tough trap to avoid. The proliferation of 3D CAD tools and easy access to affordable 3D printers has allowed the rapid proliferation of prototypes. Sometimes we have a tendency to make 3D prototypes just because we can and it’s cool. Rather, we should be striving for effective prototyping.
I was once told that if a picture is worth a thousand words, then a prototype is worth a thousand pictures. No truer words have ever been said. But if you do not fully understand what the prototype can teach you about your product, it doesn’t matter if the prototype is worth one million pictures.