Path Planning Algorithm And Software Development For Automatic Fiber Placement Of Complex Components Based On Meshed Surface

Fiber reinforced resin matrix composites are more and more widely used in aerospace field because of their high specific strength,high specific modulus and strong designability.With its flexibility and high degree of freedom,automatic fiber placement technology has become an efficient molding technique for complex composite components.Automatic fiber placement path planning is very important for the forming quality and efficiency of composite components.With the development of aerospace composite components in the direction of large size and complexity,efficient and universal automatic fiber placement path planning algorithm and software become the bottleneck of domestic composite digital manufacturing.According to the forming characteristics of automatic fiber placement technology and the requirements of manufacturing equipment,this thesis designed a path planning algorithm for automatic fiber placement based on triangulation mesh surfaces,and completed the software development and experimental verification.The specific research is as follows:The process constraints of automatic fiber placement path planning were analyzed,and a parameterized model of multiple process constraints was built.This thesis analyzed and extracted the technology defects that of laying process,extracted the geometric expression of the constraints of automatic fiber placement process for complex components,constructed multi process constraint model,and realized the mathematical description of process theory.At the same time,characterization experiments were designed to establish the relationship between the process parameters and the forming defects of components.On this basis,the parameterization method of process constraints was refined,including angle deviation constraint,curvature radius constraint,overlap and gap triangle process defects,and tow compactness constraint.A path planning algorithm of triangulation mesh surface based on curvature feature was proposed.In this thesis,the traditional parametric surface was transformed into triangulation mesh surfaces,and the intersection of plane and surface was transformed into the intersection of plane and plane,which optimized and reduced the order of equation solving.This thesis proposed the surface triangulation algorithms included surface partition discretization,cell surface boundary stitching and triangular patch geometric topology reconstruction algorithm to realize the transformation from parametric surface to high precision and low error triangulation mesh surface.At the same time,a unified mesh surface data model for automatic fiber placement path planning was established to realize efficient search and calculation of triangular patches.A center path generation algorithm of complex surfaces based on guide lines was established,trajectory deviation analysis was analyzed and parameter selection strategy was established.The automatic fiber placement path planning was divided into two parts: center path generation and tow path generation.Combining the advantages of the traditional fixed Angle method and the natural path method,a center path generation algorithm based on the guide lines was designed,and the center path direction datum updating strategy under complex curved surface was established.The optimization algorithm of path curvature was designed to improve the lay-ability and reduce the wrinkle.At the same time,the deviation analysis method of the path planning algorithm was established.The distance and angle deviation analysis were carried out for typical components and standard curvature components.The basis of surface discrete parameter selection was established by algorithm efficiency and path deviation.It clarified the discrete parameter selection principle of automatic fiber placement path planning software based on discrete mesh surface.The algorithm of high-quality tow path generation was designed,and the defect control strategy of automatic laying process was established.A new geodesic definition of discrete mesh surface was proposed to establish the graphic basis for solving the path of fiber tow.A defect-controllable fiber tow path generation algorithm,including fiber tow offset algorithm,boundary precision control algorithm,full spread realization and cutting defect control algorithm,was designed to achieve high quality generation of fiber tow trajectory of large size complex components under multi-process constraints.The software development was completed,and the efficiency and accuracy of the algorithm were proved to meet the engineering requirements through experiments.Based on this thesis,a path planning software was developed by using component application architecture(CAA),a secondary development tool of CATIA,an interactive CAD / CAE / CAM system software,which included surface meshing module,path planning module,path evaluation module,etc.Tested the algorithm and software by taking the typical components as the experimental objects.Compared with the traditional geodesic method,the efficiency of planning time was3 times higher than that of traditional geodesic method,which was 3-5 times of the foreign path planning software VERICUT.At the same time,according to the accuracy verification experiment and the actual placement experiment proved that the efficiency and accuracy of the algorithm meet the engineering requirements.