The Analysis And Applied Research Of Ultrasonic Distance Measurement Principle In Hydraulic Cylinder Displacement Survey

Ultrasonic distance measurement belongs to the category of uncontact measurement.In the condition it has advantage which contact measure doesn't has contrasting with uncontact measurement. Ultrasonic measure is not influenced by rays of light in the range ,and has simple struture,and cost cheaply cotrasting to other uncontract measurement such as laser measurement, rared ray easurement ,radio measurement. Ultrasonic distance measurement is the new distance measurement. This thesis studies the ultrasonic distance measurement,and reasearchs ultrasonic attenuation in the atmosphere and hydraulic oil,analyses the factors which inflence measurement precision. The factors include ultrasonic wave frequence ,condition temperature, ultrasonic converter instrinisic system error, hareware extended time, electricity noise and sonic noise in the spot,city power defmcient pressure and exceeded pressure,city power peak and pour. We adopt the following compensation schemes of error in the system.About ultrasonic wave frequence's effect to measurement precision ,we can choose appropriate frequence according to the measured distance. The third chapter in the paper presents a method that we can select suitable ultrasonic frequence in the analysis of the ultrasonic attenuation.Owing to temperature having great effect ,the variation of temperature is a important factor that affects the measurementprecision. The third chart in the paper presents two compensation methods. We can satisfactorily solve the question.A method is presented in order to compensate ultrasonic converter instrinisic system error.Hareware extended time is compensated .Electricity noise in the spot can be solved by metal cover and right ground connection. The ground connection method is given in the fourth chart. Sonic noise can be solved through using arithmetic mean in place of the real numerical value to increase signal and noise ratio.We use alternating voltage regulator to remove city powe defincient pressure and exceeded pressure. Owing to high frequence ,city power peak and pou can be removed by low band-pass filter that we design in the fourth chart.We give three installing schemes in the measuring hydraulic cylinder in the fourth chart and analyse thire merits and shortcomings.We discuss the possibility of measuring grinding wheel diameter by ultrasonic waveWe give the full electric circuit schemes,including emitting and receiving circuit,measuring temperature circuit,displaying circuit,regulated power supply, A/D converter circuit and so on . We emulate some of the circuit in the Protel 99 se.