Fully Distributed Region-Reaching Control with Collision Avoidance for Multi-robot Systems

SUMMARY This paper proposes a fully distributed continuous region-reaching controller for multi-robot systems which can effectively eliminate the chattering issues and the negative effects caused by discontinuities. The adaptive control gain technique is employed to solve the distributed region-reaching control problem. By performing Lyapunov function-based stability analysis, it is shown that all the robots can move cohesively within the desired region under the proposed distributed control algorithm. In addition, collision avoidance and velocity matching within the moving region can be guaranteed under properly designed control gains. Simulation examples are given to verify the capabilities of the proposed control method.

DISTRIBUTED FORMATION CONTROL AND OBSTACLE AVOIDANCE OF MULTI-ROBOT SYSTEM

This paper proposes a distributed control method for multi-mobile robots to avoid obstacles. Firstly, the Limit Cycle (LC) method is exploited to set the reference trajectory for robots to avoid obstacles. Secondly, the control rule that control a leading robot following the reference path is introduced. Thirdly, the algorithm that controls robots moving in a formation and avoiding obstacles based on the combination of the LC method and the reference trajectory tracking algorithm. Different from the distributed control algorithm in related documents, the algorithm in this paper ensures that the robot formation is not only maintained but also avoids obstacles when moving to the target. Finally, simulation and experimental results are conducted to verify the effectiveness of the proposed method.

Further Results on Finite-Time Distributed Control of Multiagent Systems With Time Transformation

In previous work, a (smooth) finite-time distributed control algorithm with time transformation was introduced for first-order multiagent systems, which guarantees convergence of the single state of agents to a time-varying leader at a-priori given, user-defined time T from any arbitrary initial conditions with bounded local control signals. In this paper, we present an extension of this previous work to second-order multiagent systems. Specifically, utilizing a user-defined finite-time interval of interest t ∈ [0, T), we time transform this class of multiagent systems subject to the considered (smooth) distributed control algorithm to an infinite-time interval s ∈ [0, ∞) with s being the stretched time. Based on a property of this time transformation, this results in finite-time convergence as the regular time t approaches to T from any arbitrary initial conditions with bounded local control and internal signals. Finally, two numerical examples illustrate the efficacy of the proposed algorithm.