Advanced Wideband Sensorless Force Control Based on Harmonic Estimation Integrated Singular Spectrum Analysis Based Disturbance Observer

This paper proposes a new sensorless force sensing approach to realize the advanced wideband force control system. The force observation is based on the harmonic estimation integrated singular spectrum analysis based disturbance observer. The singular spectrum analysis is constructed to improve the force sensing performance and achieve the remarkably wide bandwidth by effectively separating the fundamental response and noise when the disturbance observer pole is notably raised. Additionally, the harmonic estimation based on the least squares method is configured to identify and cancel the periodic component caused by dither signal in the force estimation. The proposed method achieves the high performance force sensation with considerably widened force sensing bandwidth. The effectiveness of the proposed method is verified by numerical simulation results.