Automotive prototype and engineering services provider Prefix Corporation, from Rochester Hills, Michigan, uses Delcam's PowerSHAPE CAD software and PowerMILL CAM system to develop Programmable Vehicle Models - PVMs - that enable carmakers to try out different prototype vehicle interiors and exteriors in a matter of seconds. 

Traditionally, the manufacturer's design team would build a prototype and then have engineers and consumers look at it and sit in it, and suggest changes.  Based on the comments, the designers would build a new prototype and repeat the review.  To speed and simplify the design process, Prefix's PVMs change configurations instantly, via sliding panels and movable components that are actuated by software-multiplexed electric motors.

Creating a PVM requires a wide range of talent.  The design process begins when the car manufacturer supplies Prefix with CAD files of the prototype vehicle intended for development.  Engineering Manager Mike Istok said Prefix uses PowerSHAPE to create and move the surfaces. 

"We take the customer's surface and offset it to where we can start sliding the panels over one another.  For example," he said, "in PowerSHAPE, I can take an entire hood assembly and slide it into different positions, to see what actually is going to happen with the panels that overlap." 

For both functional and aesthetic reasons, tolerances are tight.  "We make it as dimensionally tight as we can, but we have to take into consideration the build variations that occur within plastics," Mr. Istok said. 

Mr. Istok said PowerSHAPE is powerful and versatile.  "Its strength in surfacing is unbelievable.  It gives you anything you can imagine in surface manipulation, stretching a surface for a mould or making blends into other surfaces.  It beats all other systems I've ever worked with in terms of the ease and speed of manipulation," he said. 

Mr. Istok added that PowerSHAPE dynamic sectioning capabilities are important in the creation of PVMs.  "We use the dynamic sectioning quite a bit for making sure that no panels are breaking through other panels.  If a surface breaks through, we contact the customer quickly, send him a wireframe, and have him fix the problem."

Mr. Istok points out that PowerSHAPE is fully integrated with PowerMILL, which Prefix uses to create toolpaths in its milling department.  Prefix Facilities Manager Ray Rutkowski said that the company had evaluated other CAM software by running test parts and had decided that PowerMILL could do the job quicker and better.  Jason Stevelinck, NC Milling Manager, said that PowerMILL "offers speed advantages in creating toolpaths and provides a lot more control over what you can do."