Considering the high order of the unmanned helicopter’s model, it is very complicated and tedious to calculate
the virtual control signal derivatives in standard backstepping. The paper proposes a filtering backstepping controller, which
computes the derivatives of the virtual control by use of filter without having to analytically or numerically differentiate
it. Therefore, the backstepping implementation is significantly simplified. Furthermore, the derivatives are computed by
integration, not by differentiation, which helps to decrease the effects of measurement noise. Then the exponential stability
of the compensated tracking errors are proved based on Lyapunov theory. Simulation results show the effectiveness and
stability of the proposed method.