Time-varying force tracking in impedance control

Compared with the general compliance control problem where the manipulator-environment interaction force is often assumed to be a fixed value, the time-varying interaction force within position-based impedance control is studied on a 2-joint robot manipulator. Exploration of theoretical analysis and tentative improvements on time-varying force control are proposed with the improvements of traditional target impedance model. An adaptive control algorithm is additionally introduced to identify the uncertain location and stiffness of the environment, and the Lyapunov-based stability analysis is also given. Finally, Simulations are performed to verify the efficacy of the newly proposed methods in both trajectory tracking and force control.