Event-Based Haptic Tapping with Grip Force Compensation

Previous work in event-based haptics has demonstrated that augmenting position-based force feedback with high-frequency impact transients significantly improves the realism of virtual tapping. Transients can be portrayed more accurately by accounting for the dynamic relationship between actuator force and hand acceleration, a technique we call acceleration matching. This work extends the method of acceleration matching by analyzing how changes in user grip force affect the transients produced when tapping on real and virtual objects. We use this understanding to update the event-based paradigm, measuring grip force in real time and adjusting transient output accordingly. When implemented on a system that can provide high-bandwidth, high-magnitude current, this new approach successfully compensates for changes in user dynamics, significantly improving the robustness of event-based haptic tapping.