Bilateral Force Feedback Control Based on Wideband Acceleration Control

Real-world haptics is the key technology for future human support engineering. Because it is able to realize a bilateral recognition between human´s action and real environment and transmit the recognized information through human sensations. From the point of view, a future robot should act as the physical agent. Transmission performance of the environmental information to human depends on transparency of a physical agent. The transparency includes spatial and temporal characteristics. Higher spatial transparency transmits much environmental modes. On the contrary, higher temporal transparency transmits wide frequency bandwidth. To improve the transparency, the paper proposes wideband acceleration control for bilateral force feedback control. Since the conventional acceleration control obtains the acceleration information by the second-order derivative of a position response, its bandwidth is limited due to the derivative noise. To enlarge the bandwidth of an acceleration control, the paper proposes a position-acceleration integrated disturbance observer (PAIDO). Since an acceleration sensor is implemented in PAIDO, the bandwidth of the acceleration control based on PAIDO is able to outstrip the one of human´s tactile sensation. As a result, vivid tactile sensation is possible in the experimental haptic device. The experimental results show the viability of the proposed method.