A Design Tool for Producing 3D Solid Models from Sketches 2004-01-0482

A novel design tool that produces solid model geometry from computer-generated sketches was developed to dramatically increase the speed of component development. An understanding of component part break-up and section shape early in the design process can lead to earlier part design releases. The concept provides for a method to create 3-dimensional (3D) solid models from 2-dimensional (2D) digital image sketches.

The traditional method of creating 3-dimensional surface models from sketches or images involves creation of typical sections and math surfaces by referencing the image only. There is no real use of the sketch within the math environment.

An interior instrument panel and steering wheel is described as an example. The engineer begins with a 2-dimensional concept sketch or digital image. The sketch is scaled first by determining at least three known feature diameters. For example, the diameters of a radio control knob, instrument cluster display, and steering wheel should be known. The steering wheel is framed and an ellipse of the wheel is created. A circle is then generated from the ellipse by using mathematical calculations. A scale factor is determined to properly size the image of the instrument panel to the steering wheel. Steering wheel centers are aligned between the sketch image and another math-based instrument panel of similar size. The sketch image is properly sized and then morphed using computer graphics into an orthographic view from a sketch perspective view.

A future small vehicle instrument panel and steering wheel sketch image was morphed into an orthographic view using a similar instrument panel previously developed math model. The glove box and knee bolster surfaces were found to be not correctly located relative to the other math model. This information provided very early and quick feedback to the designer for correction. These components would have required full redesign if not found in the early stages.