Adaptive failure compensation for coaxial rotor helicopter under propeller failure

This paper proposes an adaptive controller to provide for failure compensation for a coaxial rotor helicopter. It addresses the problem of instability due to damage to the rotors in a coaxial rotor helicopter, where degradation of or unexpected variations in thrust from the propellers are known to pose an especially serious risk. The key problems arising out of a situation of propeller failure are identified. A detailed description of the model of the coaxial rotor helicopter is provided, and a control scheme for the same is chosen. The problem of instability along the yaw and altitude axis for coaxial rotor helicopters under propeller failure is modeled. Finally, a suitable adaptive control scheme is proposed to stabilize the helicopter´s states under propeller failure. Simulation results demonstrate that the adaptive control scheme is successful in stabilizing the aircraft in the event of damage.