The goal of this research project is to empower users to retrieve, modify and reuse 3D data reliably to create assemblies simply by drawing a freehand sketch. This will serve as the foundation for a new "sketching computing" paradigm. The approach consists of (1) allowing users to express design ideas in the form of freehand sketches while detecting 2D sketch and 3D assembly constraints. 2D and 3D constraints are detected from the freehand drawing using relative shape histogram and 3D pose determination. This allows the system to capture the user's design intentions without explicit user specifications. (2) A 3D model segmentation method is used to facilitate partial shape replacement and search through operations such as "cutting," and "pasting" partial shapes. (3) A 3D assembly technique using 2D and 3D constraint mapping is then used to enable model construction from search results.
The research goals will make design more accessible for people who are not trained in using complex Computer-Aided Design (CAD) tools. The results of this project will lead to a workable sketch-based system that could be more intuitive for designers than conventional CAD systems. This will promote better creativity during the design process and reduce the need for user training. It will also demonstrate new useful ways to integrate pen-based computing into many existing computer-application paradigms. The project Web site (www.purdue.edu/sketchlab and www.purdue.edu/shapelab) will be used for dissemination of results and providing access to the experimental system.