Modelling and control of a small-scale unmanned helicopter

The dynamical model of a toy helicopter considered as two rigid bodies is deduced using Kane's equation. Another model is presented that considers the helicopter as a single rigid body. It is shown that the response of the rotational dynamics modelled as two rigid bodies is cosine while that modelled as one rigid body is linear. In addition, a flight controller is presented that is based on dynamic inversion and model predictive control (MPC). In order to decrease the online computational effort associated with a conventional model predictive controller, an explicit MPC algorithm is introduced, which converts the online computations to offline computations to solve the real-time problem. Experimental results show that the controller is able to operate in real-time and can closely track the trajectory without overshoot.