Longitudinal-lateral velocity control design and implementation for a model-scaled unmanned helicopter

In this paper, a nonlinear controller is designed and implemented for longitudinal-lateral motion of a model-scaled helicopter. The underlying principle of controller design is the backstepping technique with slight modifications to accommodate the helicopter model. It is proved theoretically that, under the proposed controller, velocities and yaw angle of the closed-loop system are capable of tracking reference signals. A practical helicopter testbed is constructed to test the performances of the closed-loop system. Experimental results of practical flight tests demonstrate that performances of the closed-loop system are satisfactory.