Improving Haptic Device Stability through Redundancy Resolution

Employing robot redundancy is proposed for increasing the stability domain of haptic interfaces during interaction with stiff virtual environments. To this end, non-strict priority allocation is accomplished. Haptic device (HD) joint space is searched by Artificial Bee Colony (ABC) optimization algorithm to find the most stable configuration in a specific end-effector position. Sensor quantization along with viscosity and Coulomb friction in robot joints are considered in the redundant HD model without any conservative assumption. A verified 1-DOF simplified model is employed for stability analysis. The method is evaluated by studying KUKA LWR IV as a redundant HD in MATLAB.