Physical input modelling and identification for a helicopter UAV

Approaches to helicopter UAV control often use the main and tail rotor thrusts, and the main rotor flapping angles as inputs. However, servomotors control the helicopter's four physical inputs which are the main rotor cyclic and collective pitch, and the tail rotor collective pitch. Helicopter models which treat the physical input are generally intractable for model-based control. We propose and identify a physical input model which is algebraically simple and therefore suitable for use in control design. The proposed model includes the vehicle's velocity to improve its accuracy.