Control Technology Research On The Nacelletilting Stage Of Quad Tilt Rotor Aircraft

Quad tilt rotor UAV is a new four-rotor UAV which combines the characteristics of VTOL helicopter and fixed-wing aircraft cruising speed, long range characteristics. It not only greatly reduce the requirements of space flight, but also to fly in a large case load in a larger context. This is also the reason that people will look gradually shifted to these new aircraft in recent years. But the difficulty of system design is not a simple sum of the two aircraft of difficulty, because of its four rotors, and there are various disturbances and couplings, then the quad tilt rotor UAV is difficult to design. This article makes a study of the transition phase of the control system on a small tilting four-rotor UAV model.First we determine the quad tilt rotor UAV flight principle and conversion that entering from the vertical takeoff mode to the nacelle tilting the transition phase and finally to the level flight phase and give the pitch, roll and yaw attitude manipulation programs and policies in the vertical takeoff mode and nacelle tilting mode and determine the UAV speed and nacelle tilting angle of the transition corridor curve according to manipulate policy.Second mathematical model of quad tilt rotor UAV is built. First, we make a stress analysis in the case of a single propeller and the overall UAV. Next the kinetic equations and motion equation sin body coordinates, speed, coordinates and ground coordinates are studied.Third we determine the transfer function of the brushless motor, servo and motor drive through experiments and design the control law at helicopter stage and nacelle tilting stage in the use of multi-loop approach. A classic lead correction method in helicopter mode control system are applied. Since the parameter vatriation of the nacelle tilting stage, so a fuzzy PID control method is provided and simulated.Finally, we select the host controller ADu C7026 and various sensors and actuators hardware, and design the circuit. we make procedures for the preparation of a variety of interfaces and control law in the Keil compiler environment. The gyroscope noise is removed and gyroscope zero drift is corrected by accelerometer. The test results reach the initial requirements, enabling a smooth transition.