Decentralized Robust Connectivity Control in Flocking of Multi-Robot Systems

In this paper, a global connectivity control method for decentralized multi-robot systems is proposed. This method can achieve decentralized connectivity control of multi-robot network under disturbances, which has no effect on the objective flocking control. Based on the gradient between the connectivity and robot positions, the proposed connectivity control method can make each robot move along the desired gradient direction, so as to achieve the control of the global connectivity. Indeed, the flocking method based on the potential of attraction and repulsion can ensure that the distance between robots is stable within the desired range. Then the security of flocking and the stability of communication are guaranteed. It is proved in this paper that both connectivity and objective flocking control have no effect on the stability of each other, under the condition that both controllers are bounded. Therefore, the global connectivity and configuration of the system can achieve the desired states. In addition, a robust control method based on integral sliding mode is designed in this paper, which can counteract the external disturbance and ensure the ideal dynamics of multi-robot systems. Finally, several numerical simulations are given to validate the effectiveness of the proposed control methods.