Autonomous Unmanned Helicopter Landing System Design for Safe Touchdown on 6DOF Moving Platform

In this research, an adaptive control system is designed for a safe touchdown of an unmanned helicopter during its landing phase on a 6DOF moving platform. In this paper the landing phase is divided into the approach and touchdown stages. In the first stage, the helicopter tries to attenuate the initial position and direction errors and in the next stage, the platform´s attitude is tracked for a safe touchdown. The hierarchical structure of the proposed control system includes supervisory and tracking levels. The supervisory level recognizes the landing stage and the tracking level controls and compensates the errors based on SDRE (state dependent Riccati equation) method. The robustness and performance of the landing system is evaluated by computer simulation in different scenarios. The results show satisfactory tracking performance of the designed control system during landing phase on a moving platform.