Abstract
This paper investigates the formation control of a disturbed air-ground multi-robot system consisting of unmanned aerial vehicles (UAVS) and unmanned ground vehicles (UGVs). An embedded collision-free formation control scheme, comprising two main components, is proposed. Firstly, a formation signal generator is developed based on distributed cooperative control approaches and artificial potential field-based methods. The generator, functioning as a virtual multi-agent system through a network of second-order integrator-chain dynamic nodes, is designed to “achieve” the formation control task while ensuring some specific constraints. Secondly, by embedding the corresponding node within each robot and taking its outputs as the tracking references, distinct constrained tracking controllers are designed for the UAVs and UGVs, respectively. Additionally, some finite-time disturbance observers are also employed to estimate and compensate for the lumped disturbances of UAVs and UGVs. With these two components, the proposed embedded formation control scheme completes the desired formation shape asymptotically for the air-ground UAVs-UGVs system under disturbances, while the collisions are successfully avoided between any two UAVs or two UGVs. Rigorous stability analysis and comparative simulations demonstrate the effectiveness of the proposed control scheme.