Path Planning and Flight Controller Scheduling for an Autonomous Helicopter

In this article we investigate how to generate flight trajectories for an autonomous helicopter. The planning strategy that we propose reflects the controller architecture. It is reasonable to identify different flight modes such as take-off, cruise, turn and landing, which can be used to compose an entire flight path. Given a set of nominal waypoints we generate trajectories that interpolate close to these points. This path generation is done for two different cases, corresponding to two controllers that either govern position or velocity of the helicopter. Based on a given cost functional, the planner selects the optimal one among these multiple paths. This approach thus provide a systematic way for generating not only the flight path, but also a suitable switching strategy, i.e. when to switch between the different controllers.