In this paper, the robust formation control problem is investigated for a group of quadrotors. Each quadrotor dynamics exhibits the features of underactuation, high nonlinearities and couplings, and disturbances in both the translational and rotational motions. A distributed robust controller is developed, which consists of a position controller to govern the translational motion for the desired formation and an attitude controller to control the rotational motion of each quadrotor. Theoretical analysis and simulation studies of a formation of multiple uncertain quadrotors are presented to validate the effectiveness of the proposed formation control scheme.

In this article, the data-driven fault-tolerant synchronization control problem is investigated for unknown cooperative quadrotors subject to nonlinearities and multiple actuator faults in the quadrotor dynamics. A distributed observer is provided to estimate the state of the virtual leader. Based on the reinforcement learning theory, the optimal control policy is learned for each quadrotor without any knowledge of the quadrotor dynamic information. Then, the learned control policy is used to construct a data-based fault-tolerant controller to restrain the effects of quadrotor actuator faults. Stability of the constructed controller is proven and the simulation results illustrate the effectiveness of the proposed controller.

In this article, the model-free robust formation control problem is addressed for cooperative underactuated quadrotors involving unknown nonlinear dynamics and disturbances. Based on the hierarchical control scheme and the reinforcement learning theory, a robust controller is proposed without knowledge of each quadrotor dynamics, consisting of a distributed observer to estimate the position state of the leader, a position controller to achieve the desired formation, and an attitude controller to control the rotational motion. Simulation results on the multiquadrotor system confirm the effectiveness of the proposed model-free robust formation control method.

The guaranteed-performance consensualization for high-order linear and nonlinear multiagent systems with switching topologies is respectively realized in a completely distributed manner in the sense that consensus design criteria are independent of interaction topologies and switching motions. This paper first proposes an adaptive consensus protocol with guaranteed-performance constraints and switching topologies, where interaction weights among neighboring agents are adaptively adjusted and state errors among all agents can be regulated. Then, a new translation-adaptive strategy is shown to realize completely distributed guaranteed-performance consensus control and an adaptive guaranteed-performance consensualization criterion is given on the basis of the Riccati inequality. Furthermore, an approach to regulate the consensus control gain and the guaranteed-performance cost is proposed in terms of linear matrix inequalities. Moreover, main conclusions for linear multiagent systems are extended to Lipschitz nonlinear cases. Finally, two numerical examples are provided to demonstrate theoretical results.

The formation of unmanned underwater vehicles (UUVs) has wide potential for applications in various marine activities. This paper studies the robust formation protocol design problem for multiple UUVs, whose dynamics are subject to nonlinearity, parametric uncertainties, and external disturbances. A robust distributed formation control scheme is proposed, which yields a control structure involving a position loop and an attitude loop to govern the translational motion and rotational motion, respectively. Theoretical analysis is given to show the robustness properties of the global closed-loop control system. Simulation results are provided to validate the effectiveness of the proposed formation control method.