Finite-Time Approximation-Free Attitude Control of Quadrotors: Theory and Experiments

In this article, a novel finite-time approximation-free control scheme is proposed for the attitude tracking of quadrotor unmanned aerial vehicles. Prescribed performance functions are employed to transform the original attitude tracking problem into an alternative system stabilization problem. By incorporating a finite-time error compensation mechanism into the recursive control design, the finite-time error convergence, and singularity-free property can be guaranteed simultaneously. Compared with the existing approximation-based control schemes, the presented controller has a simple cascade proportional-like structure and less computational burden, and the coupling among the roll, pitch, and yaw dynamics can be successfully handled without requiring any model information or function approximations. With the proposed control scheme, the attitude tracking error can be retained within a prescribed boundary and converge into a sufficiently small region around origin in finite time. Extensive comparative experiments on a three degree-of-freedom (3-DOF) quadrotor platform are performed to validate the effectiveness of the proposed control scheme.