Integration of virtual reality techniques into computer-aided product design

The main contributions of this research include: (i) a deeper understanding of both the limitations of current CAD systems and designers' expectations of the HCIs for the next generation of CAD systems has been obtained through case studies and user evaluation tests; (ii) a new direct, more natural and more intuitive interaction paradigm has been introduced which enables designers to take fuller advantage of their visual, auditory and tactile sensorial channels to create, view, touch, manipulate and listen to CAD digital models easily and freely; (iii) a new 3D freehand sketching design tool has been created to support a true 3D design capability; and (iv) freeform feature-based design functions have been developed for use with both direct haptic and sound feedback operations