The Construction Of The Electromechanical Parameters Testing System Of Linear Ultrasonic Motor And Accuracy Study

Linear ultrasonic motors have only been developed for more than 40 years,and are used in many fields due to their many advantages.However,ultrasonic motors involve strong nonlinear behaviors such as collision,contact,and friction in the friction coupling process,which make it difficult to establish the model and theoretically evaluate the performance of the designed ultrasonic motor.Therefore,it is of great significance to construct a test system for ultrasonic motors.This paper takes the comprehensive analysis of the linear ultrasonic motor's dynamic characteristics,input characteristics,mechanical characteristics and transient characteristics as the starting point,and builds a set of multi electromechanical parameters test system of linear ultrasonic motor with perfect function and synchronous acquisition,which avoids the problems of repeated experiments to study the relationship between related parameters and improves some measurement methods of linear ultrasonic motor's electromechanical parameters.The system is composed of a computer with LabVIEW software and a hardware system mainly including data acquisition and various sensors.The main contributions of the dissertation are summarized as follows:(1)In this paper,the principle and realization method of measuring the dynamic characteristics,input characteristics,mechanical characteristics and transient characteristics of linear ultrasonic motor are studied.The error sources and error reduction methods of the existing measurement algorithms of driving electric signal related parameters are analyzed.The signal preprocessing methods of electromechanical parameters of linear ultrasonic motor are described.(2)According to the signal characteristics and synchronous acquisition requirements of the electromechanical parameters of ultrasonic motor,the overall test scheme of the linear ultrasonic motor is determined and the hardware circuit of the test system of the electromechanical parameters of linear ultrasonic motor is designed.The linear calibration of each hardware circuit is completed and the calibration device of the pull pressure sensor is designed and manufactured.(3)Using LabVIEW software,the test modules such as data collection and playback,data processing and saving,data statistics and analysis are built.From the perspective of measurement accuracy,the program automatically optimizes the setting value of sampling frequency in the data acquisition module to ensure the whole cycle sampling as much as possible.Considering the memory occupation and operation efficiency,the memory and structure of the test system are optimized.In order to improve the automation of the measurement device,the output signal of the signal generator is controlled based on the command of SCPI.(4)The dynamic characteristic test,input characteristic test,transient characteristic test and mechanical characteristic test of V-shaped linear ultrasonic motor are carried out by using the built electromechanical parameters test system.The experimental data are collected,saved and analyzed,and the characteristics of V-shaped linear ultrasonic motor are analyzed and evaluated in the form of figures.(5)This paper describes the algorithm error caused by the non-integr period sampling and the resonance frequency point error caused by the displacement resonance in terms of the theoretical application error.The zero phase filter and the method of lifting the weight to measure the output thrust of ultrasonic motor are simulated and analyzed,and experiment and error compensation for the repeatability accuracy of the system in terms of the hardware are carried out.The single-phase impedance characteristics of the V-shaped linear ultrasonic motor and related parameters of the driving electric signal from the comparison measurement of different measuring instruments are verified.