Practical and Safe Navigation Function Based Motion Planning of UAVs

This paper offers a practical method for certifiably safe operations of an unmanned aerial vehicle (UAV) with limited power and computation, useful for real-time operations where the UAV is exposed to significant disturbances in non-convex free space. We propose a motion planning method based on the Explicit Reference Governor (ERG) framework to ensure the safety of a flying quadrotor UAV. From a small set of experiment data and assumptions on modeling errors, a Lyapunov function is synthesized by which an ERG is constructed to modify the UAV set-points. The method can handle polyhedral obstacles and constraints imposed on the maximum thrust of the UAV and its maximum tilt. We demonstrate the approach with extensive simulations and experiments using a Crazyflie 2.1.