Stability of virtual reality haptic feedback incorporating fuzzy-passivity control

Abstract

This study investigated the stability of virtual reality (VR) haptic feedback from the perspective of energy. A fuzzy controller was designed on the basis of passivity theory to mitigate the shock and divergence in a virtual component caused by the negative damping coefficient and the high spring coefficient. Compared with a standard passivity controller, a fuzzy-passivity controller is more effective in shortening the time required to stabilize a system with high initial energy and devices that consume energy slowly. First, MATLAB/Simulink was employed for stability simulation and analysis. The fuzzy-passivity controller provided more favorable stability convergence than did the standard passivity controller. The simulation results align with expectations. Second, the completed VR system was applied as an experiment platform for verifying the feasibility of the fuzzy-passivity controller. To achieve one degree of freedom in the experiments, a robotic arm was exclusively designed to replace manual force. Finally, compared with standard passivity control systems, the results indicated that the fuzzy-passivity controller enables improved control over the stability of VR haptic feedback.