Design Of Control System For A Certain Type Of Aircraft Rudder Surface Fatigue Test

Aircraft contains a lot of rudder-faces, such as the horizontal tail, aileron, flap, front wing and so on. Rudder-face is the control surface of aircraft, and its deflection angle needs to be constantly adjusted to control the aero attitude during the process of flight. Thus, in the development process of the aircraft, whether each rudder-face strength design and fatigue property under certain loads meet the requirements becomes extremely important. In order to verify fatigue property, rudder-face fatigue test emerges.In this paper, since the traditional rudder-face fatigue test system exists many problems, such as low automation degree, single testing method and testing function, inflexible procedure and so on, so combined with the latest development status of the test system, a rudder-face control system with functional flexible and rich expansion capabilities is developed. The design of hardware and software is introduced comprehensively. The system uses PXI bus instrument structure, and the system's versatility and scalability have been improved. It can send sine or ramp command signals to control each rudder-face deflection, and real-time monitor the current rudder-face position information. The system also can implement automatic mode and manual mode control switching. In manual mode, instruction signal is emitted by the system to control rudder-face deflection, while in automatic mode, the command signal is emitted by an external tester to complete rudder-face fatigue test, which can greatly improve the system's automation degree. The system software design was implemented by using C++ language, and all the control functions can be completed through operation of the software interface.The system has finished all the development work and has been successfully delivered to a particular Aircraft Design and Resarch Institute. Through a great number of experiments, the system, which has features of high development level of automation,various functions, high ability of expansion, can operate stable and reliable. This system also meets the requirements of the rudder-face fatigue tests, which has high economic value in the field of aviation and military.