Fixed-time Terminal Sliding Mode Trajectory Tracking Control of Quadrotor Helicopter

In view of model uncertainties and external disturbances in quadrotor dynamics, this paper proposes a nonsingular fixed-time terminal sliding mode control method to achieve the trajectory tracking within a fixed-time time. The settling time of the closed-loop system does not depend on the initial state of the system, but only on the control parameters. So it can explicitly design the inner and outer loop settling time of the closed-loop system offline and thus the two-time scale between inner and outer loop can be explicitly prescribed. Finally, simulation results are included to validate the effectiveness of this algorithm.