Research On Complex Car Body Surface Offset Based On Trial And Error Method

It’s a huge challenge when we building complex body parts surface and it’s going to be a more difficult problem that the geometric and design parameters are not stable enough after modifying the surface.However,we could only rely on manual modification to solve the problem.The automation program based on redevelopment can solve the problem of efficiency to a certain extent,but its ability and applicability are significantly lower than manual process.Especially now,the competition in the automobile industry is unprecedented fierce,forcing enterprises to develop more efficiently,which leads many researches focuses on the more efficient development of body surface.What we must need to face is the complexity,diversity and uncertainty problem when we edit car surface model.This leads to a large number of failures and complex surfaces in the actual operation process.Statistics show that no matter how complex the model is,it is composed of a limited number of geometric operations.If the most vulnerable geometric operations can be strengthened,the efficiency of the whole modeling process will be greatly improved.Our research is based on the above ideas,and carried out in cooperation with the body development department of a domestic body enterprise.In this paper,we choose the most frequent error offset operation as the research goal,so as to realize and verify the above idea.It is found that a reasonable solution has not been found in the academic field.We know in practice that in order to solve the problem of surface offset,engineers usually try and correct repeatedly according to their own experience,which costs a lot of time and is inefficient.Therefore,based on the existing CAD geometry and engineering experience,a set of "enhanced" surface offset tool based on trial and error method is completed.Due to the reduction of human intervention,the efficiency of trial and error method is obviously lower than that of direct solution.It is an enabling process and solves the problem of surface offset error substantially.This paper will focus on solving three problems:(1)Algorithm and method,(2)Program development,(3)Parameter integration.Manual modeling is universal,but it is inefficient.In contrast,computers are efficient,but their capabilities are not comparable to those of engineers.This paper,following the working ideas of entry-level engineers to repeatedly test and error with a large number of empirical methods,has formed an expert database and knowledge engineering system,which can be used to empower the computer.This is also the starting point and characteristics of this study.In this paper,the secondary development of C / C + + is completed on Siemens NX platform,and the NX open API interface and knowledge engineering technology are used to realize the parameterization and characterization.The final results show that this method significantly enhances the effectiveness of the existing bias operation,which is also confirmed by the actual test in the enterprise.The method in this paper is a logical method based on the experience of engineers,which can solve the reliability and stability problems in the process of surface modeling.Only by solving the problem of reliability and stability,automation without manual intervention can fundamentally improve the efficiency of body design and development.