A fuzzy adaptive admittance controller for force tracking in an uncertain contact environment

Traditional constant admittance controller (CAC) in uncertain contact environment is highly dependent on environmental location and stiffness, which are always difficult to obtain in most applications. To address this problem, a fuzzy adaptive admittance controller (FAAC) based on fuzzy inference rules is proposed in this paper. Firstly, an adaptive admittance controller (AAC) that can compensate for the admittance parameters in real time based on force error information is proposed. Secondly, a fuzzy logic loop is introduced into the adaptive term of the AAC system to reduce the overshoot when force tracking, thus creating the FAAC. The detailed design method of FAAC is presented, and the stability conditions are analysed. Finally, simulations and experiments are conducted in several dynamic environments to demonstrate the force tracking performance of the proposed controller.