Obstacle Avoidance Policies for Cluster Space Control of Nonholonomic Multirobot Systems

The cluster space control technique promotes simplified specification and monitoring of the motion of mobile multirobot systems of limited size. In this publication, we summarize the definition of the cluster space framework and introduce a multirobot cluster space controller specific for unicycle-like nonholonomic mobile robots. The controller produces cluster commands that translate into valid robot-level motions. We then study the closed-loop system stability in the Lyapunov sense. Two different obstacle avoidance algorithms are proposed and the stability of the resulting systems is also addressed. Experimental tests with a three-robot system and simulation results with a ten-robot system verify the functionality of the proposed approaches.