WeHAPTIC: A Wearable Haptic interface for Accurate Position Tracking and Interactive force Control

Abstract

In this paper, a hand wearable system for virtual reality (VR), which is called as WeHAPTIC (Wearable Haptic interface for Accurate Position Tracking and Interactive force Control), is proposed. It shows improved performances in terms of finger motion measurement and force feedback compared with existing systems such as finger joint angle calculation and precise force control. Intensive experiments are also conducted to verify the mechanical performance as a haptic interface. The finger joint angles are inversely calculated by an estimation algorithm based on the fingertip positions with only one calibration posture. Not only the index finger motion which is generally measured, but also the thumb motion is accurately measured by our proposed algorithm. Accurate force feedback is achieved by robust control of the motor current. The motion measurement accuracy of average 2.62∘ errors in the thumb and index finger was verified by an infrared motion capture system. For performance evaluation of the force control, a Z-width and various interaction experiments were conducted; variable stiffness were generated, and various sizes & shapes of virtual objects were identified.