In a new series, the editors of NASA Tech Briefs magazine catch up with everyday engineers about their unique responsibilities and challenges. This week, we highlight fellow reader and CAD designer of medical devices, Michael Hudspeth.
Michael Hudspeth, CAD designer, Bausch and Lomb, St. Louis, MO
Field/Expertise: Medical Devices
What is your job title, and what does your day-to-day work involve?
I’m a CAD designer for the surgical division of Bausch and Lomb. I’m doing surgical tools for eye surgery. I design products for my client; build and support 3D solid models for production, tooling and documentation; write copy; and create graphics for documents and marketing materials. If we need prototypes, then I have to arrange for the prototypes to be made.
What are your biggest challenges when designing these medical device products?
Taking a design from concept to manufacturing. Just designing something isn’t good enough. If it can’t be mass produced, it’s just a work of art. To become a real product, you have to get to know processes and materials as well as procedures that make the technology possible.
You also have to deal with pretty tight tolerances sometimes. When you’re trying to produce a needle that goes into someone’s eye, obviously you want to make the smallest incision possible.
With your work specifically, how has CAD software improved?
It is night-and-day better. When I started out, everything was done on a drafting board with pencil and mylar leads, or paper and mylar sheets. You really had to have an artistic eye to do drawings like that; there was no other way to do it. Chances are you didn’t have a model in front of you so you had to just make it from orthographic views. If you wanted an isometric view on a drawing, then you had to figure out what it would look like. Frequently that was very difficult.
So CAD has really helped in the drafting area. It’s also helped with areas that are more downstream, like finite element analysis, so that you can make sure that your part is not just going to break on you. Then you have the flow analysis, which really is handy because then you can rely less on your experience and more on what the computer tells you.
How has rapid prototyping made your job easier?
Rapid prototyping has got to be the most exciting technology to come out of the twentieth century. It makes it easier to do “what if” scenarios. Back when the computer first became mainstream, “what if” scenarios were kind of the purview of the spreadsheet. [With rapid prototyping] you can take everything, plug in your variables, and then spit out data to see results in any given situation: If I change this or change that, what’s going to happen to the whole product?
It allows you to, in the same amount of time, create vastly different models of the same device. You can try different things and actually have it in your hand. When I first got into this, that was something that took weeks, and you had to have a model shop that would produce a prototype. Those prototypes got really, really expensive because you have a good machinist machining your plastic for you. You’d get a one-off that’s not easily reproducible, and if you break it, you’re pretty much in trouble. But with rapid prototyping you can send it off and say, “Hey I want three of these,” and you can get it back in a matter of days, and it’s a lot cheaper to do.
Where would you say are the most common hiccups in the design process, from concept development to manufacturing?
Marketing requirements are generally the places where most hiccups come. It’s been that way at every company I’ve worked for. If the marketing department asks you to do something, they’ll say “I want this product, and these are the things that I’d like to have in that product.” Invariably what’ll happen somewhere down the line is they’ll come back and say “That’s really cool. Can it do this too?” Pretty soon, you’ve got a long list of things that weren’t originally planned for but got added later, and that can significantly increase the difficulty, cost, and timeline.
Are your design tools set up for that kind of necessary flexibility?
Generally speaking, yes. It’s a whole lot easier to do that when you’re talking about CAD work. If I had to do it with a machinist on the drafting board, no way.
What is the most satisfying part of your job?
There are two. One, the more important satisfaction, is actually seeing a product that I’ve designed go out there and help people. In this particular company, it’s helping people to see better. On a more personal satisfaction, it’s kind of nice to be able to walk into Wal-Mart and see something that I designed sitting on the pharmacy shelf, or walk into a hospital and see one of my products being used and helping somebody recover from an injury.