Predictive dual-quaternion sliding mode control of underactuated quadcopter based on motion parallax

A predictive dual-quaternion sliding mode control (PDQSM) is proposed to resolve the position and attitude synchronization control of underactuated quadrotor unmanned aerial vehicles (UAVs). The method proposed is designed to achieve superior tracking performance by leveraging “predictable” real-time attitude command with the principle of motion parallax. Firstly, by taking a body-fixed displacement vector into the Newton-Euler dynamic of QUAV, another rigid body dynamic model (coordinate system origin c) that can couple the translational and rotational motion is derived. Secondly, to transform the underactuated control problem into a fully actuated control problem, a smooth predicted desired attitude trajectory (PDAT) is designed based on the above two dynamics. Then, a fully actuated dynamic model is established via the dual-quaternion formalism, which simultaneously describes the coupled motion between the position and attitude of the underactuated quadcopter unmanned aerial vehicle (QUAV). Afterward, to improve system stability, dual-quaternion sliding mode (DQSM) control is proposed. Finally, the proposed controller is asymptotically stable based on the Lyapunov stability theory. The simulation and experimental test results show that the proposed control method has higher control precision and stronger robustness.