Research On The Flight Control System Of Quad Tilt Rotor’s Helicopter Mode

Quad Tilt Rotor is a new type of tiltrotor aircraft, which has the similiarcharacteristics of the helicopter and fixed wing aircraft like ordinary tiltrotor aircraft. Ithas four tiltrotors and two pairs of fixed-wing, so it has a higher cruising speed and agreater payload and can take off vertically. Therfore, it has brilliant prospects in militaryand commercial applications and it is an important direction for the future aircraftdevelopment. This paper mainly research a Quad Tilt Rotor’s helicopter mode flightcontrol system and design feedback control laws to control the attitudes.Firstly, using the Newton’s classical mechanics, this paper deduces the mechanicaland the dynamic models of the QTR’s helicopter mode. The control strategies aresummarized and analysised, with which the mathematical model can be simplified andthe transfer functions can be obtained. Some experiments are designed to acquire theparameters of the transferfunctions.Secondly, the classical frequency methods are used to design the control law ofeach QTR’s channel, specifically the multi-loop design, the series lead compensationand PI control laws are used. The discrete controllers are get by using the bilineartransform.And then the correctnesses are verified and performances of the designedcontrol laws are simulated with the Matlab Simulink tools.Based on the previous foundations, The ADuc7026microcontroller and MEMSsensors such as MEMS gyroscope, accelerometer and other hardwares are selected toaccomplish the QTR’s helicopter mode flight control system. And the flight controlprograms are coded to manage the whole flight control system.Finally, the functions and the realiziation of the debug sofware of the QTR’shelicopter flight control system are introduced. At the end, the paper summarizes thedebugging principles and specific methods.what’s more, some system test experimentsand corresponding data curves are presented.