Adaptive Motion Control via Flexible Joint Robot Model Linearization

Flexible Joint (FJ) robots have attracted researchers' attention in these years for their good compliance and the safety. But as a matter of fact, it is hard to design a suitable controller for FJ robots due to the model uncertainties and the nonlinear systems when using elastic components. In this paper, to compensate for the unknown nonlinearities that arise in the FJ robot system and controller design procedures, we linearize the whole robot dynamic system via a known dynamic regressor matrix. It is discovered that our controller generates the desired motion quickly and avoids the cumbersome calculations, which increases applicability of the adaptive controller. By using the Lyapunov method, we prove the dynamic stability of the FJ robots' closed-loop system. Furthermore, simulation results verify that our controller greatly reduces tracking error while generating the desired motion quicker.