Distributed Coordination of Networked Manipulators: A Two-Layer Control Scheme

This article studies the coordination control problem of networked manipulators, where manipulators are actuated to cooperatively transport an unknown object along a prescribed trajectory. It is assumed that the accurate position and velocity information of the trajectory is known only to a subset of manipulators. A two-layer control scheme consisting of an estimation layer and a control layer is developed. At the estimation layer, prescribed-time distributed estimators are designed to estimate the position and velocity of the trajectory. The estimation errors are shown to converge to zero in pre-specified time. At the control layer, an event-driven distributed controller with a dynamic triggering mechanism is proposed, where nonuniform time-varying communication delays are considered. A distinctive feature of the proposed controller is that both control updates and communication occur at certain event instants, and thus control update burden and communication costs are reduced. Moreover, two adaptive time-varying control gains are designed so that the controller can be implemented without requiring any inequality condition or global information. Finally, a simulation platform based on MATLAB Robotics Toolbox is designed and implemented to verify the effectiveness and superiority of the proposed two-layer control scheme.

Automated summary

This article studies the coordination control problem of networked manipulators, where a two-layer control scheme is developed to estimate the position and velocity of the trajectory and design an event-driven distributed controller. The proposed controller reduces control update burden and communication costs by performing control updates and communication at certain event instants. Simulation results using MATLAB Robotics Toolbox verify the effectiveness and superiority of the proposed control scheme.