Trajectory Tracking of a Quadrotor Underwater Delivery Platform via Adaptive Sliding Mode Control

A new Quadrotor Underwater Delivery Platform (QUDP) was proposed for underwater transportation, in which its configuration has been well used in air quadrotors. But there are still new challenges to controlling such robots underwater. In this paper, a complete dynamics model of QUDP is established first. Then, the trajectory tracker is designed as the control outer loop based on the adaptive sliding mode (ASMC) under an unknown time-varying load, and the stability is proved by using Lyapunov stability theory. Meanwhile, the PD controller is designed as the control inner loop to track the change of attitude angle. Finally, it is verified by numerical simulation. The results show that the proposed controller can perform well with an unknown load and improve the robustness of the system.