Research Of Micro-mass Measurement System Based On Vibrating Cylinder Sensor

Recently, the demand for high precision micro-mass instruments measurement is increasing gradually. They are widely used in fields like chemistry, biology and facial disposal.There are two kinds of products in micro-mass measurement fields—the electronic scale and resonant micro-mass measurement instrument and they practically dominate the whole market. The precision of electronic scale is not high enough while the resonant one is outstanding in precision but with a high prize and the key techniques are protected by patent. Due to the factors above, we introduce the resonant tube sensor, which has been fully studied, to the micro-measurement field.Work has been done as follows:Designed a double-channel F/D converter based on CPLD with outstanding synchronous and high speed feature. The two channels can perform simultaneously and the core counter designed in it has 32 bits width. Also, considering the upgrade of hardware in the future, a double channel F/D converter based on NIOS2 was designed.Further, developed the related hardware , a system that is composed of CPLD and MCU, which is used to gather and deal with the frequency and temperature data from resonant sensors and then displayed them through LCD.At last, a general understanding on the systerm's features of micro-mass measurement can be seen after a series of experiments on small scrips of different shape and weight. And the resolution of the system is up to 1 ug scale. The system performs well and stably, all of which make a good foundation for further study and commercialization.