Safety and Performance of Industrial Collaborative Robots: Bounded Compensation in Precision Motion Control

Abstract

<p>The safety and control performance of industrial collaborative robots must be ensured while they are executing repetitive and precise tasks alongside human workers. This study proposes a new motion control structure to enhance the safety by demonstrating full-body compliance while achieving control performance as accurate as that of conventional industrial controllers. For precise motion, the proposed approach introduces a nominal model and compensates for disturbances caused by model uncertainty while bounding the compensation input for the safe interaction. Furthermore, to reduce the interaction forces without compromising the control performances, a method for designing the compensation bound based on the Gaussian Process (GP) is proposed. The proposed approach can achieve a uniformly ultimately boundedness (UUB) in the tracking scenario and asymptotic stability in the regulation scenario. The effectiveness of the proposed approach is validated under various conditions through experiments conducted using a 6-DOF industrial collaborative robot.</p>