Adaptive Cooperative Output Regulation for Multiple Flexible Manipulators

This article studies the cooperative output regulation problem for multiple flexible manipulators. First, based on a two-parameter-correlated adaptive law, a new fully distributed observer is proposed. Different from the existing works, the observer does not depend on global graph information and can handle the uncertainties in the leader system. Second, a barrier-function-based sliding mode disturbance observer is proposed for the flexible manipulator to estimate the state-dependent disturbance. This new disturbance observer does not depend on the exact form of the disturbance. We show that the fully unknown state-dependent disturbance can be estimated and rejected in finite time. Finally, based on the proposed sliding mode disturbance observer, a new adaptive controller is proposed. The controller does not require the tip-end state information of the flexible manipulator, which is beneficial for the implementation. Both simulations and experiments show the validity of the presented method.