DentalTouch: A haptic display with high stiffness and low inertia

Designing haptic devices with both high stiffness and low inertia is challenging. In this paper, we propose a solution to overcome the difficulty. We present a new haptic device named DentalTouch for dental simulation. Combining parallel and serial mechanisms, the DentalTouch can render 3-dimentional forces and 6 degree-of-freedom (DOF) motions. We describe how to achieve high stiffness and low inertia in the DentalTouch by using co-actuation method recently developed by our group. We evaluate the stiffness and inertia performance of a DentalTouch prototype through analytical and experimental approaches. The results show that the combined structural and motor control stiffness of the prototype is within the range of 21-69 N/mm and the inertia ranges from 113 to 163 g in task workspace, which demonstrates that the DentalTouch has a potential to provide a high stiffness and low inertia.