Microprocessor based new technique for measuring pneumatic pressure using optocoupler controlled vibrating wire transducer

A new and sensitive pneumatic pressure measuring device is proposed. The sensor consists of a diaphragm and a string fixed inside a hollow cylinder attached to a pneumatic medium. While one side of the diaphragm is exposed to pneumatic pressure, the string is stretched on the other side. With the use of a microprocessor, the string is periodically excited through an electromagnet and the vibrating frequency is measured from the signal obtained at an optocoupler. The frequency is calibrated to indicate the pressure.<
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