Fault Detection Method And Application Research On Helicopter Air Data System

Through the research on the Air Data System of aviation,the thesis have completed fault detection work on military helicopters,Air Data Measurement System relying on cooperation with troop,a complete set of in situ,out-bit detection scheme is proposed,and the scheme can be applied to the helicopter second-line maintenance task.Fault detection equipment for Air Data System Mainly used for its performance calibration and fault detection,the target detection mainly includes air data computer,altimeter,airspeed,vertical speed indicator,and some other related functional components.Subject to Air Data as the main research object,to develop the portable instrument detection equipment by using advanced pneumatic technology,pressure sensing technology and modern virtual instrument technology,finally to realize the function of situ,out-bit detection on Helicopter Air Data Measurement System,and meet the helicopter flight security needs.The user can use the test equipment to provide the air pressure simulation environment for functional components which related with Helicopter Air Data System.At the same time,the function of performance calibration and fault detection in situ and out-bit environment can be realized.Referring to the international standard of Air Data,the conversion relationship between the Air Data and the air pressure is deduced in thesis,and the derivation of the mathematical model is introduced in detail.The overall design of the situ,out-bit detection system scheme is introduced,and the construction of the high precision air pressure control system is completed,which can simulate the total pressure and static pressure of the equipment.Then the hardware development platform based on the hardware system of virtual instrument is introduced,and the hardware component circuit design is accomplished.At last,using graphical programming software LabVIEW as the developing tool,to control the air pressure by controlling the high-speed switch electromagnetic valve with pulse width modulation(P WM)signal,and then the software of the system is written,and the software program of the man-machine interface is finished,and the function of the fault detection is realized.This set of system implementation makes up the deficiency of domestic in such airborne equipment and also for military helicopter flight security escort.