Design News for Mechanical and Design Engineers

That's what one senior executive involved in product design told me recently. And, he really meant it.

Yeah, and we live in a paperless society, right? Wrong.

Of course computer simulation has been a great boon to design engineering, enabling engineers to dramatically increase the number of design iterations they can do, and also cutting down the number of physical prototypes that they need. Computer simulations have truly helped engineers.

But don't think that computer simulation eliminates the need for physical prototypes. No way.

Physical prototypes are important for at least two reasons: 1) people make mistakes and 2) well-designed products take into account the tactile as well as the visual elements involved.

Now admittedly, I have a stake in the use of physical prototypes because that's the business I'm in. But that doesn't make my opinion any less valid.

People make mistakes in product design for several reasons. Often, it's difficult to visualize a complex geometrical shape on a computer monitor. Or, it's hard to see certain elements clearly on the screen that may be hidden from view. After all, real products are three-dimensional, and the monitor or paper printout offers only two-dimensional representations. In achieving an appealing shape for a new product design, the designer may have created an object that's impossible to manufacture. A prototype in the manufacturing manager's hand can quickly bring the issue to light.

Some think Virtual Reality solves the prototype problem. It doesn't. Virtual Reality was sold as a magic technology that would create a world for the user that could simulate every facet of a physical experience, instantly and with virtually no operating cost. This is very appealing on the face of it. However, the reality of Virtual Reality falls short of its promises. First of all, it is generally limited to a visual experience and completely misses the tactile element. Secondly, it is not portable, so its use is limited to those within physical proximity of the equipment. Finally, it requires a substantial initial investment.

The logic behind using electronic prototypes and eliminating physical prototypes seems to be that physical models add too much time and cost to the design process. When viewed in a larger scope, however, physical prototypes in fact reduce the time and cost to get a new product to market.

A classic example is when some nurses in a marketing feedback group evaluated the new design for a remote medical device controller similar to a VCR remote. The design looked great on the screen, but a physical prototype showed that the buttons were clearly difficult to access due to the keypad layout. Time and again, designers find that they can improve ergonomics and visual appeal, while simultaneously reducing the number of flaws in a new product design by using physical prototypes.

So of course prototyping is necessary, despite the advantages of computers. After all, do you use less paper now than before? I'll bet the answer to that is "no."