Research On Laser On-line Flatness Measurement System Based On FPGA

Flatness is an indicator of the difference between the surface of the steel plate and the absolute level,which reflects the degree of warpage of the steel plate.Accurately obtaining the flatness information of the steel plate and feeding it back to the steel plate shape control system in real time is of great significance for the production of high-quality steel plates.In this paper,the three-point measurement technology scheme based on laser triangulation is adopted,and XC7A35 T FPGA is used as the main control and processing chip to study the steel flatness measurement system.The thesis firstly analyze and study the current research status of flatness measurement of steel plates at domestic and abroad,as well as three typical flatness measurement methods and determine technical solution of the flatness measurement;then,according to the technical requirements of the project,the overall design of the measurement system was designed.In combination with the optical system based on the three-point measurement method,key components such as a semiconductor laser with a wavelength of 450 nm,a TCD1304 AP linear array CCD,and gigabit network port communication method based on UDP transmission protocol were selected;Based on this,the system hardware design with FPGA and linear array CCD as the core and the system software design with laser spot positioning as the core are carried out;finally,the performance of the photoelectric conversion circuit,the accuracy of laser spot positioning,and the effectiveness of the three-point measurement method are verified through experiments.The results show that the laser flatness measurement method used in this paper can effectively avoid the impact of the steel plate up and down on the detection.