Study On Particle Size And Shape Measuring System Based On Dynamic Image Technique

The performance of material is closely related to the particle size and shape parameter,the particle size and shape measurement has become the important work of material production application,Dynamic image analysis methods has been applied widely since it has the characteristics of large sampling volume,no orientation error,no adhesion particle overlapping,and it can measure the particle size and shape at the same time.The research contents of this paper include the design of the particle size and shape measuring dystem based on dynamic image technique,the image acquisition,pre-processin,the particle extraction,defocus blurred image and the particle size parameter measurement.1.a parallel light source and double telecentric lens,high-speed camera and industrial equipment was used to establish particle size and shape measuring system based on dynamic image technique.vibration feeder make the the dispersion of particle free fall when the particles fall into the area of measurement volume,camera will gain the image of the dispersion of particle under the parallel light source.2.pre-processin procession start to process the image of the dispersion of particle,gray-scale image correction,uneven background removal,image smoothing was used to enhance image contrast,meanwhile system should eliminate all kinds of noise,adaptive threshold value make the image deaperate from the background image and the final segment the image was gained.3.binary particle image was processed by the morphological processing and removed the small particles,and smooth the irregular edges of the particle,on this function,minimum enclosing rectangle was determined by the contour tracking,extract the image of each particle,the number of connected domain analysis edge detection algorithm particle image edge.If the number of the edge is more than 2,then the image was eliminated by the determination of defocus blurred.4.the particle size parameters such as the perimeter,area,particle size,major axis and minor axis have been calculated,and the grain size parameters such as eccentricity,circularity,squareness and aspect ratio.The experimental results turned out that particle size and shape measuring system based on dynamic image technique can measure the particle shape parameters quickly and accurately it also overcome the shortcoming that easy adhesion overlap,little sampling of static image method,the measurement results accurancy can get a rate above 95%.