Framework for modeling and validating concept designs in virtual reality environments

A computational framework for representing and manipulating rigid and deformable objects in VR space is described in this paper. The core algorithms for haptic rendering, collision detection and physics modeling used within this framework assume that all 3D objects are B-spline surfaces. The tool can be represented as a B-spline surface, an implicit surface or a point, to allow the user a variety of rigid or deformable tools. The `collision detection system' utilizes the fact that the transformation matrices used to discretize the B-spline surface are independent of the position of the control points and, therefore, can be pre-calculated. Finally, the `physics modeling system' uses the mass-spring representation to determine the deformation and the reaction force values provided to the user. This helps to simulate realistic material behavior of the model and assist the user in validating the concept design before performing extensive product detailing or finite element analysis using commercially available CAD software. The novelty of the proposed method stems from the pre-calculated transformation matrices used to generate the points for graphical rendering, nodes for the mass spring system and collision detection. This approach reduces computational time by avoiding the need to solve complex equations for blending functions of B-splines and perform the inversion of large matrices. This will also help to do away with the need to build prototypes for conceptualization and preliminary validation of the idea thereby reducing the time and cost of concept design phase and the wastage of resources.