Research On The Optimization Of The Shape Of The Steel Needle Tip And The Puncture Length Of The Integral Puncture Of The Three-dimensional Fabri

The holistic puncture three-dimensional fabric is a special carbon fiber three-dimensional fabric with good holistic structure and high fiber volume.It is an excellent substrate for making high-performance heat-insulating carbon/carbon composite materials.At present,the fabric is widely used in high-tech fields such as aerospace.China’s holistic puncture technology has achieved major technological breakthroughs,but in the holistic puncture process,there is a problem that the holistic puncture steel needle tip and the holistic puncture template contact damage the holistic puncture steel needle tip,and the holistic puncture steel needle bar has strength damage,in order to improve It is necessary to carry out the research on the shape optimization of the whole puncture steel needle tip for the service life of the puncture steel needle.Based on the analysis of the research status of carbon fiber three-dimensional fabric forming equipment and holistic puncture needle tip shape optimization at home and abroad,this paper studies the shape optimization of the whole puncture steel needle tip.The main research contents are as follows:The whole puncture process and the orthogonal lamination woven carbon cloth are analyzed in the movement mode and mechanical behavior of the fibers in each puncture stage.According to the geometric relationship between the yarn and the holistic puncture needle movement,the yarn tension is established.Mechanical model of each puncture stage.In order to meet the strength requirements of the holistic puncture steel needle,the allowable stress of the holistic puncture steel needle and the total puncture needle tip curve are established in order to satisfy the strength requirement of the holistic puncture steel needle under the tension of the yarn.The function relationship is based on the function to optimize the shape of the needle tip of the holistic puncture steel needle.The tip and the needle bar of the whole puncture steel needle are respectively tempered by the superposition method,and the displacement of the needle tip of the whole puncture steel needle at the apex is obtained.Use the map multiplication method to find the displacement of the tip of the whole puncture steel needle at the apex.In order to avoid the contact between the needle tip of the whole puncture steel needle and the puncture template,the relationship between the number of curves of the puncture needle tip and the total displacement limit condition is established,and the shape of the whole puncture needle tip is optimized according to the function.Use machine vision to select a reasonable algorithm to identify the displacement parameters of the holistic puncture needle tip,and use bilateral filtering to remove noise during image acquisition.Use the displacement parameters provided by machine vision as a training sample for machine learning.By predicting the six algorithms,the prediction model is selected to predict the holistic puncture length,and the algorithm is optimized by the grid search method.Considering the actual grinding of the needle tip of the whole puncture needle and reducing the processing cost of the puncture steel needle,the shape of the needle tip of the whole puncture steel needle is further optimized.According to the optimized steel needle tip model,the whole puncture steel needle is trial-processed,and the holistic laminated woven carbon cloth puncture experiment is carried out.