Robust Fault-Tolerant Control of an Aerial Manipulator System With Varying Center of Mass

Most existing control methods for aerial manipulator systems (AMS) are developed under the assumption that the system's center of mass (CoM) is known and fixed. In this study, a dynamic model of the AMS that accounts for time-varying CoM is developed, and based on this model, a robust fault-tolerant control strategy is designed. First, by using Lagrangian modeling method, the centroid theorem and the parallel-axis theorem are applied to construct a dynamic model of the system that considers the time varying CoM. Second, a single-neuron linear active disturbance rejection controller (SN-LADRC) is proposed, where the fixed parameters of the traditional linear state error feedback (LSEF) are replaced by online-adjustable gains, thereby enhancing the con troller's adaptability to load variations and external disturbances. Furthermore, a fault-tolerant controller based on adaptive non singular fast integral terminal sliding mode control (ANFITSMC) is proposed, which can adaptively estimate faults and suppress steady-state errors simultaneously. Finally, MATLAB simulations validate the accuracy of the proposed modeling approach and demonstrate the effectiveness of the designed control strategy in terms of response speed, robustness, and fault-tolerant capability.