Suppressing Initial Force Overshoot Using Admittance Filter and ASMC under Contact Location Uncertainty

Abstract

This paper proposes a control method to mitigate initial force overshoot caused by contact surface position estimation errors. The proposed method adds a compensation term based on Adaptive Sliding Mode Control (ASMC) to a conventional admittance control structure. Also, to maintain position tracking performance under model uncertainty, a hierarchical control structure is designed by combining a Time-Delay Control (TDC)-based internal position controller. Simulation results show that the proposed method reduces the maximum overshoot from 76.6% to 32.1% compared to conventional admittance control, and shortens the peak time from 0.254 s to 0.126 s. Furthermore, the settling time is reduced from 3.51 s to 1.467 s at the 2% criterion and from 2.113 s to 0.832 s at the 5% criterion, improving transient response stability and convergence speed.