Distributed Control of Multiple Flexible Manipulators With Unknown Disturbances and Dead-Zone Input

Multiple flexible manipulators can be used to complete some repeatable missions. Each flexible manipulator can be described as an underactuated Lagrangian system based on the assumed modes method. Also, the actuator nonlinearity may deteriorate the system performance. Hence, this article aims to develop a distributed controller to solve the leader-follower consensus of multiple flexible manipulators with uncertain parameters, unknown disturbances, and actuator dead zones. The disturbances are classified as repeatable and nonrepeatable ones. The adaptive, iterative learning, and sliding-mode control techniques are used to handle uncertain parameters, repeatable, and nonrepeatable disturbances, respectively. Based on a dead-zone inverse and a finite-time observer, a distributed controller is developed to drive the flexible manipulators to track a moving leader and keep the flexible vibrations bounded simultaneously. Experimental results are presented to verify the effectiveness of the proposed controller.