Research And Design Of Steel Plate Thickness Measurement System Based On Laser Triangulation

Steel industry plays a key role in economic development.Steel plate is an important product of steel industry.In order to ensure product quality and reduce cost,thickness measurement is very important in the production and use of steel plates.At present,the thickness measurement method of steel plate is mainly applied to Ray thickness measurement or electromagnetic ultrasonic thickness measurement.The former has high accuracy,but it is easy to cause radiation damage to human body.The latter has fast response speed,but the application requires close measurement,which has great limitations.Therefore,it is particularly important to design a non-contact,high resolution,high stability and low cost steel plate thickness measurement system.Based on the above problems,this paper designed a thickness measurement system based on laser triangulation method to realize the small thickness measurement system for steel plate sample sampling or production experiment environment.In this paper,the principle of laser triangulation thickness measurement is firstly studied and analyzed.A differential thickness measurement method is designed to directly measure the thickness of steel plate without considering the reference surface.In order to solve the problem of noise affecting system accuracy and stability when image sensor collects spot image in laser triangulation measurement,an improved Gaussian filter is used to deal with image noise.According to image filtering denoising evaluation,the improved filter can improve system denoising effect.Aiming at the problem of calculating space and calculating time of measuring system,the design of embedded FPGA parallel running and pipeline is adopted,and the function of hardware circuit interface timing and hardware logic timing is realized by compiling comprehensive tool.The experimental results show that the thickness measurement system can be realized by building the hardware measurement device and software processing function based on the differential direct laser triangulation method,and the absolute error of the system is less than 50 um.Through the time and space stability test,the thickness measurement system has high stability and high resolution.