Research On High Precise Mechanical Vibration Cymometer

In order to avoid unintended loss caused by vibration, the vibration monitoring of equipment are increasingly important and the frequency of vibration is the most important test object in the fault diagnosis. However, the amplitude of mechanical vibration is too low when many mechanical devices in normal operation and the test results is not ideal if we use the conventional sensor.According to the energy conservation law in this issue, a special vibration measurement sensor is designed which amplify mechanical amplitude before the mechanical parameter into electrical signal. This paper research on vibration measurement sensor amplification principle, find the function between magnification and geometrical parameter and go into more detail on the function by control variable method.In terms of the hardware circuit, the capacitance-voltage converting circuit is designed to convert the capacitance value into voltage signal. In order to achieve high-speed data sampling, the high-speed hardware acquisition circuit FPGA as the core is designed. Acquisition circuits select 12-bits ADC which the maximum sampling frequency up to 40 M and store converted data in the FPGA internal cache RAM. In software design, the FPGA internal sampling control module、PLL、memory are designed and finish the sampling timing control circuit simulation diagram. To nanosecond precision vibration time measurement, using special software interpolation subdivision algorithm for zero-crossing signal time and the time resolution of the theoretical time up to 0.244 ns, laid a theoretical foundation for the development of high precision frequency measurement instrument.