Study On Ultrasonic Liquid Level Meter

Today, the ultrasonic liquid level meters are diversiform. Most of them use the instrument of temperature compensation to obtain the real ultrasonic velocity in order to improve the measurement precision. But it needs a temperature measurement unit, so the error is added.In this thesis, a new way of ultrasonic liquid level measurement, which is based on the compensation of ultrasonic velocity by a baffle reflecting the ultrasonic, is studied. It is timed that the ultrasonic transmitted by AT89 series single chip microcomputer. The liquid level can be measured exactly by this kind of instrument. It has advantages as the former meters, and simplifies the system, improves the precision and reduces the cost.The characteristic of ultrasonic velocity compensation by a baffle reflecting the ultrasonic is studied in this thesis. And it is talked where and how the ultrasonic sensor and the baffle are installed, and whether they would affect the measurement result.In the system, AT89S52 single chip microcomputer controls the entire system which based on the principle of ultrasonic reflecting on barrier. It can measure the liquid level, display the data and implement communication function. In the study, it accomplishes the design in hardware and software, in addition the system debugging. This kind of ultrasonic liquid level meter will apply widely and have a bright future.