Adaptive compensation of aerodynamic effects during takeoff and landing manoeuvres for a scale model autonomous helicopter

Control of a scale model autonomous helicopter during takeoff and landing manoeuvres has proved to be an extremely difficult problem. This is a consequence of the slowly time-varying and environment dependent nature of the aerodynamic forces encountered along with the high sensitivity of the helicopter to collective pitch changes during these manoeuvres. In this paper we propose a novel approach to the control problem for such manoeuvres. The proposed control design uses the motor torque rather than collective pitch as the principal control input and takes advantage of its reduced sensitivity to aerodynamic effects and structural properties to develop a parametric adaptive control algorithm that estimates the principal aerodynamic effects on-line.