Research On Remainder Detection System For Aerospace Electronic Equipments

Aerospace electronic equipments installed on the satellite, space station, spaceshuttle, are used to complete the measurement, control, computing, communicationsand other tasks of functional parts which are the important components of aerospacesystems. Aerospace electronic equipments’ reliability determines the aerospacesystem stability and operational life. The loose particle in the aerospace electronicequipment is one of main influence factors for reliability. Researching on looseparticles detection system for aerospace electronic equipments has a greatsignificance for improving the reliability of aerospace systems.The existing particle detection methods mainly adopt Particle Impact NoiseDetection (PIND) method. This method is mainly suitable for sealing electroniccomponents which have small volume and weight. However, the aerospaceelectronic equipment is larger and more complex, traditional testing methods cannot meet the demand for its high test accuracy. Combined with the characteristics ofdevices and traditional testing methods, automatic particle detection system ispresented for aerospace electronic equipments.Overall system program is presented as follows: Large power shaking table isused to provide mechanical condition for the detection. Multi-sensor is used indifferent locations to collect particle impact noise signal. Then, sound pulses aretransmitted to the computer. Through the PC algorithm, detection and materialidentification of particles are achieved.In this paper, Data is preprocessed with the method of adaptive threshold pulseextraction, pulse matching and optimal pulse extraction. Particle and componentsignals are distinguished with the method of four-channel pulse intensity trendconsistency. In order to identify the material types of particles, time domain andfrequency domain characteristics are seclected as features, which are mapped intoneural network.According to the industrial demands, automatic particle detection system isdesigned for aerospace electronic equipments. With analysis of noise propagationmechanism, the special fixture which can isolate noise from shaking table isdesigned. In order to transmit the particle impact noise to the computer, the signalamplification circuit and the four-channel high-speed data acquisition card isdesigned. Using VC++and MATLAB mixed programming, the PC software iscompiled. It can achieve data’s showing, saving, loading and automaticallyanalizing the presence and material types of particles.This study has an important theoretical significance and practical value forimproving the spacecraft’s operational life and performance. The results of this paper can also be expanded to the application of other aerospace electronic devicesreliability testing fields.