Power-Shaping Model-Based Control With Feedback Deactivation for Flexible-Joint Robot Interaction

This letter presents a novel control methodology that is based on an amalgamation of model-based, power-shaping (PSC), and feedback deactivation. It has been hypothesised proportional position flexible-joint robots can impinge their interactional performance, since causes ‘stiffening’ the robot's joints. In order to reduce reliance upon terms, this work proposes usage feedforward, model-based whilst accounting for both actuator link coordinates. The introduced PSC signal enables stable tracking control, even when controller's error term employs solely non-collocated state feedback. also demonstrated user stably deactivate pertaining specific joints, in real-time manner, so as further enhance performance. However, deactivation lead abrupt generation unfeasible signals, variable impedance (VIC) technique proposed overcome limitation. Despite VIC's potential inject undesirable amounts energy into closed-loop system, amended guarantee stability preservation. Moreover, achieve saturation prevention efficient Lyapunov function unconstrained modulation system's active gains. Experimental results involving Rethink Robotics Baxter robot corroborate theoretical analyses, addition demonstrating performance improvements be achieved via methodology.