Research And Application Of 3D Printing Layering And Path Planning Algorithms

3D printing technology is a rapid prototyping technology.It has been widely used in architectural design,aerospace materials,automobile manufacturing and other fields since the 1980 s,especially in the dental and medical industries.3D printing technology has the advantages of high efficiency,rapidity and convenience,which can greatly improve the efficiency of denture processing,thus meeting the huge demand of denture in dental medicine.Meanwhile,because it uses digital model to design workpiece prototype,the printed denture shape is more accurate and personalized,and it can have a better repair effect on the patient's mouth.Therefore,3D printing technology is gradually becoming a dental department.The mainstream of the industry.The digital model used in 3D printing can be converted into a processing code recognizable by the printer after data processing,so the data processing result will directly affect the final printing result.Therefore,in-depth research and optimization of key algorithms in the data processing process can help improve the printing accuracy and printing efficiency of the model.The main contents of this paper are as follows:Firstly,this paper makes an in-depth analysis of the STL file format and its data organization structure for 3D printing.For the redundant data in the STL file,according to the characteristics of the data in the STL file,a hash function is designed to improve the performance of hash table and speed up the reading process of STL file.Meanwhile,the topology of the entire model is established and the preprocessing of the model data is completed.Secondly,the basic layering algorithm is expounded.Aiming at the problem of model characteristics offset,this paper analyzes the characteristics of the current slicing algorithm,finds out the cause of this problem,and proposes an adaptive slicing algorithm to effectively prevent the model feature from shifting.Firstly,the height of the feature is identified and adjusted.Then,slicing is performed at the determined feature height,and the top height method is employed for adaptive slicing between every two adjacent feature heights.This slicing algorithm can effectively prevent the model features from shifting,and at the same time reduce the number of layers and improve the printing efficiency while ensuring the surface quality of the model.Then,several commonly used contour filling algorithms and their advantages and disadvantages are studied,and the mixed filling method is adopted.Aiming at the situation that there are many cross-section contours on a single printing layer,the characteristics and shortcomings of three commonly used data processing software path planning are analyzed.A contour printing sequence planning algorithm based on dynamic programming and an approximate contour printing sequence planning algorithm are proposed,which are used for the cases of less than 20 contours and more than 20 contours respectively.This method can effectively reduce the total length of the idle stroke generated during the contour transfer and improve the printing efficiency.Finally,The G code is introduced,and the method of automatically generating G code is explained.A comparative printing experiment is carried out in this paper.The results show that the optimized data processing algorithm can transform the digital model into the correct processing code.Meanwhile,it can effectively improve the problem of model feature offset.Under the premise of ensuring the surface quality of the model,it can reduce the printing time and improve the printing efficiency.In addition,it is verified that the algorithm can be effectively applied to the actual denture 3D printing.