Spatial Sketch System for Car Styling Design

It is undesirable for car designers to wait long for a physical mockup, or to learn a difficult CAD interface. This paper presents a Spatial Sketch System that provides a sketch-like modeling interface, and realizes 3D drawing for human oriented industrial design, such as car styling. The designer can draw lines and surfaces directly and freely in the canvas of 3D space by operating a pen-type pointing device while viewing a stereoscopic display. The process of modeling consists of two parts: Rough Sketch and Refinement. In the Rough Sketch, the user works his/her ideas out rapidly by drawing free-formed curves and surfaces. This is an expansion of the ordinary 2D sketch into a 3D digital tool, and is useful for the conceptual design that is the first stage of car styling. It provides multi-layered canvases and colored pencils that are selected from a 3D floating menu. An erasing command is performed just as if a real eraser rubs drawn objects out. Then, in the Refinement process, precise tracing of the sketched surfaces completes the refined NURBS model. Functions to assist the user are also implemented. For example, commands of frequent use are selected by simple gestures. For example , a curve is removed when the designer shakes it quickly. This enables faster command selection than that depending on a typical menu-based interface. All commands are saved so that the designer can undo and redo them to rapidly compare alternatives in creative design work.