Automatic Landing of Small Helicopters on 4DOF Moving Platforms

In this research, an automatic control system is designed for landing a small helicopter on a J^DOF moving platform. The platform has three translational and one directional degrees of freedom. The controller design approach is based on development of the helicopter nonlinear dynamic model into the SDC (State Dependent Coefficient) form and the real time solving of the State Dependent Riccati Equation (SDRE). To compensate the simplifications and term eliminations necessary to make the SDC form, a nonlinear compensator is added. The performance of the control system in automatic landing is evaluated by computer simulation in different scenarios. The results show satisfactory tracking performance of the controller during landing phase on a moving platform.