Research On Needle Positioning Vision System And Automatic Knitting Needle Of Cross Stitch

With the growth of cross-stitch market demand,it has become an inevitable trend of the development of the cross-stitch industry that machine cross-stitch replaces artificial cross-stitch.The computer embroidery machine has been taking on the main role in the process of the industrialization of cross stitch.Nowadays,the development of the cross-stitch industry puts forward higher requirements on the level of automation and intelligence of computerized embroidery machines and the high quality of embroidery products,and the development of pattern-making techniques plays a decisive role in satisfying such requirements.In this paper,based on the current situation of the crisscross plate making technology in China and many defects in the quality of the existing cross-stitch products produced by machine,The machine vision technology was used for the pinhole positioning of the cross-stitch embroidered cloth,and the cross-stitch embroidery spectrum extraction method and the automatic knitting needle method were studied to achieve the goal of improving the level of automation and intelligence of the cross-stitch industry and improving the quality of the embroidery products.First of all,aiming at the quality problem that the stitches and holes cannot be aligned in the machine cross-stitch finished product,machine vision is adopted to identify the pinholes of embroidered cloth,and then guide the positioning of the embroidery needle to improve the quality of the cross-stitch products.The equipment selection of machine vision was completed,the hardware platform of machine vision was set up,and the calibration algorithm of vision system was studied.Secondly,the pretreatment algorithm for the image collection of embroidered cloth is studied.For the special requirements of fabric hole identification,the image processing methods and steps for extracting the center coordinates of the embroidered fabric hole were studied in detail and verified through experiments.Experimental results show that this method can obtain more accurate identification results,and the identification error of embroidered fabric pinhole is less than 0.2mm.Thirdly,in order to meet the requirement of cross-pattern automatic platemaking,an information-oriented platemaking method with cross-stitch embroidery is proposed,and the method of converting ordinary pictures into cross-stitch embroidery spectrum is mainly studied.Experiments show that this method can extract the ideal cross-stitch embroidery spectrum and meet the information-oriented requirements of automatic knitting needles.Finally,based on the embroidered mesh information obtained by machine vision,the cross-stitch path planning(automatic needle knitting)of the cross-stitch embroidery spectrum was studied.The principle of path planning based on color blocks is proposed.The path planning is divided into two stages:inter-block path planning and intra-block path planning.The intra-color path planning algorithm uses a graph algorithm to perform cross stitch path search.For the inter-block path planning,the embroidering sequence and the embroidering starting point of each color block are determined according to the requirements of the embroidering process and the principle of the shortest path.Experiments have proved that The above algorithm can be used for embroidering grid information acquired by machine vision to convert embroidery patterns into cross stitches and meet the requirements of machine cross stitch.