Inner and outer loop nonlinear controller design of miniature unmanned helicopters

Considering the small inertia and quick response of angular velocity of the miniature unmanned helicopters, an inner-outer loop nonlinear controller is presented based on the simplified model. In the inner loop, a robust H_∞ static output controller is designed to control the angular velocity. And in the outer loop, a pole assignment method is used to control the position and yaw angle after dynamic transformation of control surface. Then the controller is compensated for the whole model. The obtained control method has solved the problem of the difficulty of the nonlinear controller to be implemented, and obtains good trajectory tracking performance. At last, simulation results illustrate its high stability, robustness and good trajectory tracking performance.