Distance Measurement Of Chemical Raw Material Storage Tank By Ultrasonic Underwater Based On STM32

Ultrasonic measurement belongs to non-destructive testing field,stable performance.During the actual chemical production,ultrasonic measurement can be well used in many domains,such as chemical raw material storage tank measurement which may contains toxic or corrosive liquid.Currently,ultrasonic distance measurement products sold on the market mainly are applied in the field of air medium,while seldom comes to the liquid filed,even some products related to liquid circumstance may lead to the high price.Due to this present narrow ultrasonic test situation,finally designed an ultrasonic liquid test system based on the chip of STM32,in particular to STM32F103 VET6 which contains a high-precision analog-digital converter.Realize the high precision and real-time test requirement of chemical raw material storage tank.Module design has been adopted to hardware design in this system,to realize main functions like ultrasonic transmit and receive,signal conditioning,data acquisition and display function etc.Hardware modules use high-precision,low noise devices.STM32's PWM function of timer and related peripheral circuit lead to ultrasonic transaction.Input capture is another important function of timer,by setting the appropriate threshold to detect useful echo.Signal conditioning module designed for complicated ultra echo,mainly made up by amplifier,band-pass filter and logarithmic amplifier circuit to filter out the interference noise signal which was existed in echo.Analog signals get improved before send into ADC through hardware.In the software design,using threshold and storage address to derive the echo peak location,simplify the hardware circuit,echo's peak value can be detected effectively.Test result shown the accuracy underwater distance measurement,but this design cost less than those on the market.In the practical engineering application aspect has certain prospect.