Design, implementation and flight verification of a versatile and rapidly reconfigurable UAV GNC research platform

This work presents the design, development, and flight test results of a rapidly reconfigurable autopilot for small Unmanned Aerial Vehicles, along with the ground station software, and hardware-in-the-loop simulator. The autopilot presented differs from current commercial and open source autopilots mainly as it has been specifically designed to: (i) Enable easy modification of all the algorithms supporting the autopilot tasks, including both position and attitude estimation, inner and outer loop control and high-level navigation. This is done by using the advanced capabilities of The Mathwork's Simulink; models are directly transferred to the autopilot through the Real-Time Workshop's code-generation capability. (ii) Decouple the traditional tasks of position and attitude estimation, navigation, and flight control by using two Digital Signal Controllers (one for each task) interconnected via a Serial Peripheral Interface; and (iii) Interact directly with Simulink as a fully capable and versatile Hardware-in-the-Loop simulation engine.;These new capabilities are achieved by offering a seamless workflow of redesign, software simulation, hardware-in-the-loop simulation, and actual flight tests. The autopilot capabilities are demonstrated by implementing an L1 output feedback adaptive controller, adopted from the newly developed theory of fast and robust adaptation. Flight test results show significant resilience to severe UAV rudder failures that are consistent with the theoretical claims of the L1 methodology.