Realization Of High-accuracy X-ray Thickness Measurement System Based On LabVIEW And Wavelet Analysis

In the production of sheet metal,the measurement accuracy of thickness measurement system directly affects the quality of the sheet product.In order to meet the high quality requirements of automotive,shipbuilding,real estate and other high-end areas,high accuracy and fast response of the online thickness measurement system is necessary.The online thickness measurement system's main task is to achieve the thickness measurement and monitoring,to meet the high-accuracy requirements of thickness measurement.This paper developed a high-accuracy X-ray thickness measurement online system for small and medium-sized cold rolling sites.It makes the detailed designs from three aspects to improve the measurement accuracy: improving the performance of X-ray power,the thickness data de-noising algorithm and the anti-electromagnetic interference ability.(1)X-ray power supply design used the technique of full-bridge soft switch,the integrated regulate circuit and bi-directional voltage multiplier circuit to enhance the voltage output and reduce the ripple.(2)The system utilizes the wavelet toolbox of MATLAB to de-noising the thickness data with the wavelet analysis algorithm,which improved the data accuracy and played the advantages of MATLAB in engineering application.(3)Aimed at the electromagnetic interference of the industrial field,the system designed the anti-interference measures both in hardware and software,to improve the stability of the system and ensure the measurement accuracy.In the design process,LabVIEW was used to build the PC software,which achieved the thickness of the data and waveform online display,historical data storage and query,and also equipped with alarm systems.The lower computer adopted DSP2812 controller to realize the control of the X-ray power and the sampling of thickness data.The system has completed the design and test of the prototype,which improves the accuracy of the thickness measurement system for the metal sheet,and meets the requirements of sheet thickness measurement in the cold rolling plant.