Closed-loop incremental dynamic control allocation with actuator constraints and application to attitude control of aircraft

This paper proposes a novel dynamic control allocation algorithm which considers dynamic characteristics of actuators and takes a closed-loop incremental form to accommodate the dynamic characteristics of multiple actuators with limited bandwidths and constraints on both magnitude and changing rate. The dynamic allocation is formulated as an optimization problem, the objective function of which considers the incremental error between the desired virtual command and its counterpart implementable by multiple actuators, subject to constraints on actuators. Meanwhile, the objective function also takes into account the smoothness of variations of actuators by introducing a weighted error term. The optimal solution is obtained via a constrained quadratic programming with only inequality constraints to reduce the computation complexity of the dynamic allocation algorithm. A numerical simulation is conducted to verify the proposed allocation method, and then the method is applied to the aircraft attitude control. Compared with the existing dynamic control allocation algorithm, the proposed closed-loop incremental dynamic control allocation algorithm can improve the stability and precision of the aircraft control system in the presence of realistic actuator dynamics. Meanwhile, the proposed double closed-loop system structure provides better convenience for the performance improvement of the over-actuator system with multiple actuators.