Distributed Cooperative Control of Heterogeneous Multiagent Systems for Air-to-Ground Formation

This paper is concerned with a distributed cooperative formation problem for a heterogeneous multiagent system with a car-like mobile robot, a quadrotor, and an omnidirectional wheeled mobile robot. In the heterogeneous multiagent system, a three-layer distributed cooperative formation control strategy is constructed to achieve air-to-ground formation, the car-like mobile robot tracks a virtual leader, the quadrotor, and the omnidirectional wheeled mobile robot track the car-like mobile robot. Two nonlinear leader-follower controllers based on exponential virtual control laws are designed to maintain formation for the quadrotor and the omnidirectional wheeled mobile robot. A kinematics controller with continuous functions, an improved adaptive sliding mode controller and a suitable back-stepping controller are introduced in the heterogeneous multiagent system, respectively. Multiagent communication is one of the key steps to accomplish multiagent time synchronization. Experimental results are given to illustrate the applicability of the proposed distributed cooperative control strategy.