Three-Dimensional Distributed Affine Formation Maneuver Control of Fixed-Wing UAV Swarm with Actuator Faults and Saturation Constraints

This paper tackles the challenging problem of distributed affine formation maneuver control of fixed-wing UAV swarm considering the 6-DOF flight dynamics with actuator faults and saturation constraints. The UAV swarm adopts the “multi-leader-multi-follower” structure with directed network topology. A novel multi-layer control framework is proposed to achieve 2 objectives: affine formation maneuver control and robust fault-tolerant flight control. In the upper layer, a new kind of distributed fixed-time state estimator (DFXTE) is designed for each leader and follower UAV to generate the affine formation maneuver reference trajectory. In the middle layer, the kinematics controller is designed to track the commanded maneuver reference trajectory. In the lower layer, a sliding-mode-control (SMC) based robust fault-tolerant outer-loop dynamics controller is designed to achieve speed tracking, and a robust inner-loop dynamics controller is subsequently developed based on the backstepping method to precisely track the corresponding inner-loop angles and angular velocities with actuator faults. In the inner-loop controller, a fixed-time extended state observer (FTESO) based active disturbance rejection control (ADRC) is adopted with a novel kind of adaptive super-twisting algorithm (ASTWA) to enhance the system robustness. Moreover, an auxiliary compensator is to preserve the actuator saturation constraints, and adaptive neural networks (NN) are applied to approximate and compensate the flight dynamics coupling. Finally, numerical simulations are conducted and illustrate the effectiveness of the proposed multi-layer control framework for the affine formation maneuver control of the fixed-wing UAV swarm under the actuator faults and saturation constraints.