Research On The Control Problems Of Tiltrotor Aircraft

Tiltrotor aircraft is a new kind of aircraft which has the advantages of helicopters and fixed-wing aircraft. It not only can realize within narrow space such as helicopters as vertical take-off and landing, but also can adapt to high-speed cruising over long distances.This aircraft is a multiple input multiple output time-varying nonlinear systems, and the flight control problem is very complex. Within the development of UAV technology, a new combat theory profoundly changes in high technical conditions.So this aircraft receives worldwide attention.In aviation and aerospace field, many of the controlled objects are nonlinear time-varying systems, whose engineering control methods are usually used to use based on feedback and compensation PID control.However, when the controlled object parameter variation is bigger, the realize is changing the PID control parameters by switching the attitude control aircraft.In this paper, using model reference adaptive control method achieves the vertical flight attitude control when nacelle angle is changing. This method does not require switching control rate, also reached a good control effect.Sensorless brushless DC motor is the very important practice in this paper. The method of counter-electromotive force detection has been selected to define the rotor position.Through debugging and calculating, the best time for the motor has been found and the motor achieves stability in high-speed operation.Finally, in the paper a tiltrotor aircraft model was made.Through a large number of experiments.Tiltrotor aircraft vertical takeoff and landing attitude control was achieved in using gyroscopes and microprocessors and brushless motor.