Force sensation plays an important role in force control systems. The bandwidth of force sensing is vital to reproduce the vivid force information. Generally, sensor-less force control systems use the position-sensor-based disturbance observer for force estimation. The bandwidth of force sensation as well as the control performance, however, is limited by the noise problems. This paper proposes a method to achieve the high performance force sensing. In the paper, the force estimation operation is performed by a combination of a Kalman-filter and a disturbance observer implemented in a field programmable gate array (FPGA). The wide bandwidth force sensing can be attained owing to the shortened sampling time by FPGA. Moreover, the noise in the force information is suppressed effectively by the Kalman-filter. The experimental results show the viability of the proposed method.
2011 by the Institute of Electrical Engineers of Japan