HYBRID GEOMETRIC-BASED QUATERNION CONTROL FOR ALTITUDE AND AGGRESSIVE ORIENTATION TRACKING OF QUADROTOR UAV

This paper proposes a hybrid control algorithm that combines geometric tracking control (GTC) with special orthogonal group SO(3) for position tracking and quaternion orientation-based attitude tracking control (QOATC) in order to achieve trajectory tracking with high attitude maneuverability for quadcopter systems suffering from aggressive orientation. Firstly, to solve the problem of the limitation of executing large-angle maneuvers in a quadrotor system caused by the lack of globality or uniqueness in Euler angles models, an improved geometric controller is constructed on SO(3). Secondly, an advanced attitude quaternion-based controller guarantees the tracking performances in finite time and addresses the persisting issue associated with Euler angle-based solutions. The proposed controller guarantees stability and precision by leveraging nonlinear control methods, with thrust and torque computed directly in the body frame. Furthermore, the theoretical research assures the asymptotic tracking and boundedness of all signals in the closed loop system by utilizing Lyapunov's stabilization theory on SO(3). Several numerical simulations are presented to demonstrate the superiority of the proposed approach, showing accurate trajectory tracking, reduced position and velocity errors, and robust performance under aggressive conditions. The hybrid controller effectively avoids singularities and ensures global stability, making it suitable for real-world UAV applications requiring high performance.