A VR-based CAD System

The performance of current Computer-Aided Design (CAD) systems is still far from the satisfaction of conceptual designers. This paper presents a VR-based CAD system for conceptual design by applying VR interfaces and geometric modelling techniques to improve the human computer interaction. The system uses an electronic data glove as an input device so that conceptual designers are allowed to use hand gestures to conduct various geometric shape operations instead of depending solely on keyboard and 2D mouse. We employ the 3D GUIs for enhancing the gesture interface. The implemented shape modelling techniques offered by the system include: destruction, construction, and techniques for freeform feature creation and modification. The destructive techniques allow the user to arbitrarily sculpt an existing part by means of sculpting tools. The constructive techniques allow the user to assemble an object by using a collection of feature objects, by either adding or subtracting feature objects from the model. The system also offers several novel methods for facilitating intuitive modification of freeform curves and surfaces.