Simulation of deformable objects is central for progressing virtual reality research. The challenging task is to meet the conflicting demands of real-time interactions and accuracy. To generate natural 'feeling' from virtual reality, visual and haptic feedbacks require high refresh rates of 30 and 1000 Hz?C respectively. However, any physically accurate and realistic virtual object modeling is computationally expensive. The goals of this research project are as follows. 1) Development of new algorithms for accurate deformation of non-rigid virtual objects with a large number of vertices in real-time. The new algorithms will improve the Finite Element Method (FEM) which has physically accurate models but needs intensive computation. To meet the requirements of robustness and satisfactory visual results, the proposed model will be built based on a tetrahedral mesh structure. A preprocessing stage will be used to compute a set of elementary deformations of the model to obtain real-time performance. To simulate cutting in the dynamic deformation system, the model will be successively recomputed to remove the tetrahedron at the contacting places with haptics. 2) Simulation of deformable objects in real-time virtual reality applications. Two simulations will be developed: needle insertion into the skin for medical practices; and DNA extraction from agarose and polyacrylamide gels for biological experiments. 3) Testing and evaluating of the deformation to achieve optimal simulations, which will be performed by engineering, biology, and nursing students at Purdue University Calumet (PUC).
The proposed research will improve the fundamental knowledge and enhance the realism and immersion of haptic virtual reality. The applications in this research will benefit medical practices and biological experiments. The simulation data will be used as a basis for developing future projects on virtual reality. The long term goals of the proposed research are to 1) advance the state-of-the-art virtual reality technologies, and 2) broaden the virtual reality applications in multiple areas such as education, health care, and manufacturing, as well as bring improvements in such issues as safety, time, space and equipment, and cost efficiency. Course enrichment and student involvement will enhance the engineering program at PUC, which is located in an economically disadvantaged region.
