Research And Development Of Automatic Verifiction Device For Image Type Steel Ruler

As the simplest length measuring tool,steel ruler is widely used to measure parts size and so on.However,the automation verification of the steel ruler has been one of the problems that the Metrology Department needs to solve urgently.In order to meet the increasing demand for the measurement and verification of the industrial informatization,it is urgent to find a fast,efficient and accurate verification method for the Metrology Department.Because of its complicated operation,slow detection speed and inaccurate data,the traditional method of visual estimation error is becoming more and more difficult to adapt to the demand of the current market for steel ruler.Therefore,on the basis of the existing technical level of the Shaanxi Institute of metrology,this subject designs and develops an automatic measuring device for the indication error of steel ruler based on the image method.The measurement method is to compare the steel ruler with the standard ruler,collect the line image through the CCD camera and get the error.This device has the characteristics of high cost performance,digitalization,automation and so on.It can realize the standard,accurate and fast measurement of the indication error of steel ruler.Firstly,the thesis studies the development and application status of the machine vision image detection technology,and then determines the design scheme of the verification device according to the actual situation and design requirements of the project.Secondly,the design and implementation of the verification device structure,hardware and software are discussed in depth.The device is based on the step motor to construct a moving guideway platform,and combines the high precision grating ruler to form a closed loop control motion system,which drive the CCD camera to collect the contrast image of steel ruler and third-class standard metal linear ruler,and get the indication error by image processing.The software of the system is designed and developed by C#,which can finish the accurate positioning of the guideway,the image acquisition and processing,the analysis of the error data and the production of the standard verification report.Finally,the verification device is tested by experiments and its error is analyzed.This verification device overcomes the disadvantages of low efficiency,poor accuracy and time-consuming and laborious of the traditional measuring method,and realizes the automatic measurement of the indication error of the steel ruler.Through the measurement experiments of different types of steel ruler,the result show that this device can measure the indication error of the steel ruler quickly and accurately,and meet the demand of the current steel ruler verification market.