Autonomous Landing Transition Flight Controller for Tri-Copter Tilt-Rotor UAV Using Gain Matrix Scheduling Approach

This research focuses on developing an automatic control strategy for unmanned aerial vehicles (UAVs) equipped with a tri-copter tilt-rotor configuration, enabling them to fly in fixed-wing or VTOL mode. The transitioning between fixed-wing and VTOL flight poses challenges due to highly nonlinear dynamics during the transition process. This research aims to create an optimal flight controller using a set of Linear Quadratic controllers with a scheduling approach to control a tri-copter tilt-rotor UAV during landing transition which consists of a steady symmetric level flight and hover with zero velocities. The optimal gain matrix will be obtained by solving the Riccati Equation based on a set of linearized equations of motion across flight conditions during the flight condition phase. The designed control strategy demonstrates a successful steady symmetric flight followed by an autonomous landing transition within 62.1 seconds.