Virtual Prototyping of a Concept Car

In this 1996 study sponsored by Prince Corporation in Holland, Michigan, a virtual prototype of a concept car was created from a partial design developed using Alias. The process of converting Alias datasets into a polygonal representation with a manageable polygon count for real-time viewing in immersive virtual reality was at the heart of this project.

Concept cars are being designed to study new ideas. Most of these designs are never built. Virtual reality provides a tool for evaluating such designs in full scale without building time consuming and costly physical prototypes. In this concept car, the unusual idea of two arms extending on each side of the steering wheel to bring control switches closer to the driver was explored.




Steering wheel with control arms and virtual menu for selecting interior colors
Web size (69K) - Max size (332K)




Viewing the concept car in immersive virtual reality using the CAVE
Web size (27K) - Screen size (373K) - Max size (459K)


The principle steps for creating this virtual concept car are similar to the processes described in detail in "Virtual Prototyping of Automotive Interiors" and include tessellation, decimation, stitching, texture mapping, calibration, and others. In this project, tessellated Alias datasets typically yielded extremely high polygon counts as needed for high quality rendering. For real-time viewing, a complexity reduction process (polygon count decimation) was developed that still delivered renderings of acceptable quality. This is illustrated below for the steering wheel.


Polygonal representations of steering wheel:



Original dataset with extremely high polygon count
Max size (324K)




Reduced polygon count after complexity reduction
Max size (324K)


Rendering results:



High rendering quality for original polygon count
Web size (63K) - Max size (324K)

Acceptable rendering quality for reduced polygon count
Web size (63K) - Max size (324K)


A similar process was applied to all parts of the design. The images below show the final, reduced polygonal meshes on the left and the rendering results on the right. The close-up illustrates the overall geometric complexity of three-dimensional polygon meshes.



Outside view: reduced polygon meshes
Web size (47K) - Max size (223K)

Outside view: rendering result
Web (67K) - Screen (321K) - Max size (416K)




Close-up view: polygon meshes
Web (94K) - Screen (359K) - Max size (441K)

Close-up view: rendering result
Web size (55K) - Max size (335K)


The concept design consisted only of a partial car without outer panels, wheels, and other elements. However, the reader may have noticed that some of the images include an outer shell. We found the exterior model of a Porsche that, by chance, seemed to fit around the concept design perfectly. We used it to add an automotive touch and, as a result, increased the polygon count significantly. An upgrade in our computing power, however, enabled us to view the model in real-time at an acceptable frame rate.




Partial design of concept car
Web size (71K) - Max size (382K)




Addition of outer shell: polygon meshes
Web size (47K) - Max size (231K)

Addition of outer shell: rendering result
Web size (69K) - Max size (444K)

Last Update: December 7, 2002, kpb
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