Partially distributed multirobot control with multiple cameras

We present a new method for visual control of a set of robots moving on the ground plane. As contributions, we first propose a purely image-based control strategy that drives the set to a desired configuration while minimizing at all times the sum of the squared distances the robots have to travel. This homography-based method, which has low computational cost and generates smooth trajectories for the robots, is then used in a multirobot control framework featuring multiple cameras, each of them observing a subset of the robot team. In particular, we present a novel control approach that makes the complete robot set reach its global target configuration when there exists partial overlap between the subsets of robots observed by the different cameras. Each camera is associated to a control unit which sends the control commands to its observed subset of robots, but no other communication is required between the robots or control units. Our method, which overcomes the field-of-view limitations of single-camera methods and increases their scalability, exploits the advantages of both centralized and distributed multirobot control strategies. Simulations are provided to illustrate the performance of the proposal.