Maneuver Guidance and Formation Maintenance for Control of Leaderless Space-Robot Teams

A basic problem for a group of space-based robots is how to maintain a rigid formation during orbital maneuvers. To a leaderless team with homogeneous space-based robots, a multirobot controller architecture is proposed in which information flow is included. For each robot, there are two coupled feedback loops with different control objectives. One feedback loop is for guidance and is designed so that each robot can rapidly maneuver and rendezvous at the target point in a neighboring orbit. The other feedback loop is for formation control and is designed so that all robots in the group maintain a desired formation during a maneuver. A modified linear quadratic regulator method is used to design the guidance and control laws, where separate performance indexes are used for the two loops. By analyzing the interaction between the formation control and the maneuver guidance, a new restriction on the communication topology is proposed. An estimator for the state of the formation center is included in this control loop, and to guarantee a consensus on the formation center state estimates among all of the robots, a distributed Kalman filter based on the consensus algorithm is developed. Simulation results demonstrate the approach.