Control System Design On The Transition Stage Of Quad Titl Rotor Aircraft

Quad tilt rotor aircraft, which possesses the advantages of helicopter andunmanned fixed-wing aircraft, is attracting many researchers because of its verticaltakeoff and landing characteristics and high-speed cruise capability. Compared to V-22,this aircraft enhances the load capacity. Meanwhile, the difficulty of control systemdesign also increases. In this paper, the control system of transition phase is designedon homemade Quad tilt rotor aircraft model.Firstly, the aircraft model is established and the airspeed-nacelle angle transitioncurve is obtained by analyzing the tilting features of the aircraft. Depending on themanipulation scheme, it is divided into helicopter acceleration mode and nacelle tiltmode. The dynamics and kinematics models of the two modes are established by usingclassical mechanics methods.Then every part of the aircraft is abstracted as transfer function according to theexisting model. According to the system features of the two models, the classic PIDand advanced calibration is selected for the helicopter mode, the parameter self-tuningmethod for the nacelle tilting mode. The two controllers are designed and simulated inSimulink, which proves that the frequency domain and time-domain response of eachchannel meet the design indicators.Then the components selection of control system is done according to requiredcomputing speed, control accuracy of controller and the PCB circuit design is finishedbased on ADuC7060microcontroller. For the precision requirements of feedbacksignal, the complementary filter fusion algorithms are designed to compensate for thedefect of MEMS sensors. On this basis, the flight control framework of transitionalstage is designed and the programs of flight control law solver, attitude acquisition andcommunication interface driver are written in the IAR compiler environment.Finally, upper monitor interface is designed in LABVIEW to detect the movementand attitude of aircraft and to adjust control parameters. The sensor filtering and theeffect of fusion algorithms are verified through a series of experiments. The debuggingmethod of PID control system is described and test results meet the requirements byverifying the control results of each channel.