Input Shaped Trajectory Generation and Controller Design for a Quadrotor-Slung Load System

Quadrotor-slung load systems offer a versatile method for transporting payloads. With these systems, it is particularly important to mitigate and manage unwanted payload swinging through the careful design of flight trajectories and controllers. Tracking input shaped trajectories for instance is an effective way to minimize post-flight swinging for rest-to-rest maneuvers by allowing some swinging motions during flight. In this paper, we first present a computationally simple method to generate input shaped quadrotor flight trajectories for non-rest-to-rest maneuvers. We then propose a controller to track these shaped trajectories and permit the associated payload swinging while also rejecting unwanted swinging disturbances. The path planner and controller are implemented in simulation and the performance of the controller is compared against two simpler controllers for an input shaped u-turn maneuver both with and without an initial swinging disturbance. The results of these simulations demonstrate the effectiveness of our path planner, while also showing that the proposed controller outperforms both baseline controllers considered.