Development Of Aircraft Vibration Sensor Calibration Device

The four electromagnetic velocity transducers installed on the aircraft's engine are the key devices for monitoring the engine's working condition,they are used to reflect the magnitude and development trend of the engine's vibration in order to found the malfunction as quickly as possible,forecast the damage,determine the rework cycle and replace the engine in advance.The performance of the transducers will not only affect the reliability and stability of the whole aircraft test system directly,but also affect the safety of the aircraft indirectly.In order to meet the requirements of calibrating and repairing the vibration sensor of a certain aircraft and the follow-up new aircraft,based on the current use status quo of an existing aircraft vibration sensor calibration device.In this paper,we have developed a new type of aircraft vibration sensor calibration device.The new device can not only guarantee the safety of the aircraft engine,but also can improve the maintenance efficiency of the aircraft vibration sensors,which has important military and economic significance.Thus the theme of the paper has strong pertinence and important development significance.The thesis uses a back-to-back comparison test method to build the hardware platform.And we have developed the testing software on the basis of the VC++6.0,verified the function and assessed the accuracy of the sensor calibration device.Thesis mainly completed the following several aspects work:1? Research the theory of vibration calibration and some common calibration methods systematically,analysis the working principle,internal structure and input and output relationship of the standard sensor,measured sensor,charge amplifier,electromagnetic vibration table,power amplifier and signal generator.Furthermore we use a back to back comparison test method to build the vibration calibration device and analysis the signal circulation relationship.2?Based on the vibration velocity,frequency,working range and overload amplitude of a certain type of vibration sensor,we derive the range of each device's parameters according to their input-output relationship and selected the appropriate model,and finally make some suggestions about the design process.3?In Win XP system,we make use of the MFC to develop functional modules and calibration modules on the basis of the hardware platform.The functional modules include data acquisition module,waveform output module,self-test module,data saving and loading module,etc.And the calibration modules include working range module,sensitivity module,frequency module and amplitude module.Finally we make some suggestions about the software design process.4?We have tested the sensitivity,frequency characteristics,working range and amplitude characteristics of a certain type of vibration sensor on the base of the hardware platform and PC software.What's more,we assess the accuracy of the sensor calibration device according to the standard values in the curriculum,which proved the effectiveness of the vibration calibration device.At the same time,we recommend some points about the test process.The new device can not only be applicable to a certain type of vibration sensors,but also meets the requirements of new aircraft vibration sensors as long as the software adds some test points,thus the new device has a strong expansibility.