Persistent coverage control for a team of agents with collision avoidance

In this paper, the idea of persistent coverage to be accomplished by multiple agents while avoiding collisions is considered and developed. The persistent coverage problem is formulated by assuming that the coverage degrades over time. In this framework, our contribution is a new distributed control law which is capable of carrying out the persistent coverage without computing agents׳ paths explicitly. The proposed setup considers agents with nonholonomic motion constraints and it is based on the combination of local and global strategies to achieve efficient coverage while avoiding bottlenecks such as local minima. The local strategy is based on the gradient of the coverage error in the neighborhood of an agent whereas the global strategy leads the agents to uncovered areas of the domain. Furthermore, we present a new bounded potential repulsion law and a proof of safe navigation is provided for the case of unicycle vehicles. We also propose a modification of the tangent-bug algorithm to deal with multiple non-point agents which allows the team to navigate in environments with non-convex obstacles in a reactive manner. Simulation results illustrate the performance of the proposed control law.