ℒ1 adaptive control of parallel kinematic manipulators: Design and real-time experiments

In this paper, the recently developed ℒ₁ adaptive control strategy is experimentally validated for the first time on a parallel kinematic manipulator. The ℒ₁ adaptive controller is known for its decoupled estimation and control loops which enables fast adaptation while guaranteeing robustness of the closed-loop system. The control scheme is experimentally implemented on a 4-DOFs parallel kinematic manipulator. Based on the obtained experimental results, a comparative study shows that the proposed ℒ₁ adaptive controller outperforms the PD controller in terms of tracking performance thanks to the compensation of the nonlinearities in the adaptive controller.