Research On An Integrated Small Vibration Sensor

Now in the vigorous development of China’s aerospace industry, vibration sensorplays a more and more important role in aerospace measurement system. At the sametime, in order to increase the load ratio of the rocket or missile, increase the load withthe effective portion of rocket or missile, requirements on all devices are gettingsmaller and smaller, more and more light. Based on the trend and demand, this thesisdeveloped a comb-finger capacitive sensing element is the key part of the whole lightand small vibration sensor. The sensor has the advantages of small volume, lightweight, low noise output characteristics, reached space system realize all thelocalization of each part of the sensor requirements.This thesis first makes a comprehensive investigation on the acceleration sensordevelopment situation both at home and abroad, the sensitive element of the sensor aredescribed detailed contrast, presents the main technical specifications of the sensor.Then analyzed the main part of the sensor, conditioning circuit of sensor design of thedifferential amplifier, band-pass filtering part, at the same time, the noise is small,electronic components packaging and reasonable, and the sensor size and internalstructure diagrams are given.The principle of capacitance of the sensor used is analyzed, the effect of structureon the sensor sensitive index, considering the reduced nonlinear, reduce the noise andimprove the impact resistance and other factors, determine the sensitive structureadopts a folding beam fixed comb type structure. Simulation by ABAQUS finiteelement analysis software of various structure parameters are selected, the parametersensitive structure. The capacitance detection circuit was designed, the small vacuumpackaging design to the sensitive element.After the design is completed, the sensitive structure was carried out by usingABAQUS software (-40℃～85℃) simulation analysis of the temperature field withinthe temperature range, proves its good temperature performance. Then the vibrationtest system and test method of various performance indicators of the sensor wasdesigned. Finally, several times, the dynamic, static performance test and shockspectrum tests on the sensor, obtained the reliable results, the results meet the design requirements.