The Development And Research Of Car Body Manufacturability Analysis System Based On Interference Distance Inspection

A concurrent engineering based on manufacturability design is adopted in the research and development of modern automobiles.Aiming at the problems of low efficiency,easy omission and inconsistent inspection rules,a manufacturability analysis system based on interference distance inspection was designed.The system can improve the efficiency of engineering analysis and enhance the inheritability of analytical experience.Specific research contents include:(1)The relevant technical basics required to develop the system is consulted,and then the system is modularized for each checkpoint.The system is divided into seven functional modules: matching hole inspection,hinge axis inspection,foaming parts inspection,RPS hole inspection,interference inspection between RPS point and weld spot,lap joint inspection and welding stud inspection.(2)The core algorithm of the analysis system is to extract the features.In order to filter the required features,it is necessary to acquire the non-parametric entity model and transform the entity into the B-rep boundary expression model.According to the characteristics of the B-rep model,the B-rep model is decomposed into point,line and surface information and judged.(3)In this paper,the cylindrical surface screening algorithm in the characteristics of circular holes and slots is described,and the irregular holes are extracted according to the edge closure.When extracting the solder joint,the radius is calculated from the center point of the center of gravity and the vertices of the entity,and the volume and surface area of the sphere are determined.The welding stud is screened by using the method that the center points of all cylindrical faces in the welded studs is on the same axis.(4)In order to determine the exact position of the part in the assembly,the relative coordinate system of each part is converted to an absolute coordinate system by using the pose matrix of the part.(5)System development and verification.With CATIA/CAA as the development platform,a body manufacturability analysis system based on interference distance check was developed by using Visual Studio tool.The system is tested by an example to verify the reliability and usability of the system.