Method for calculating contact state of assembly matching surface with geometric errors

Abstract

The invention discloses a method for calculating the contact state of an assembly matching surface with geometric errors. The method comprises the following steps of: placing coordinates of actually measured points in a matching surface A and a matching surface B under the same three-dimensional rectangular coordinate system; solving the minimum distance d when the two matching surfaces are in primary contact by fixing the matching surfaces A, and translating the matching surfaces B along the assembling direction by d to realize primary contact; determining rotation information of the second contact through a slice solving method, and rotating the matching surface B to realize the second contact; based on the second contact, obtaining rotation information of the third contact through a slicing method, then rotating the matching surface B to achieve the third contact, and taking the whole third contact point set as a record to be stored in a result set; on the basis of any two contact points in all contact positions generated by previous contact, performing rotating according to a slicing method to obtain a new contact point set record, and storing a non-redundant record; and repeating the steps until no new contact point is generated, and stopping the algorithm.

Description

technical field [0001] The invention belongs to the technical field of mechanical assembly, and in particular relates to a method for calculating the contact state of assembly mating surfaces containing geometric errors. Background technique [0002] At present, in the actual assembly process of precision components, assembly errors occur due to the inconsistency between the ideal size of the assembled parts and the actual size, and the actual size of the assembly needs to be measured during the assembly process or after the assembly is completed. It is precisely because the measurement of the actual assembly size is a posteriori logic. If the manufacturing error of the assembly parts is large and does not meet the assembly size standards, it will lead to waste of assembly time and have a huge impact on the assembly process. [0003] In order to solve the problem of dimensional error transmission in the simulated assembly process, many current researchers hope to adapt to th...

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Problems solved by technology

It is precisely because the measurement of the actual assembly size is a posteriori logic. If the manufacturing error of the assembly parts is large and does not meet the assembly size standards, it will lead to waste of assembly time, which will have a huge impact on the assembly process.

[0003] In order to solve the problem of dimensional error transmission in the simulated assembly process, many current researchers hope to adapt to the current problem background by improving the collision detection algorithm based on the rigid body assumption, but the collision detection algorithm is suitable for judging whether there is a collision between moving objects, and preventing collision avoidance problem

According to the research background of this subject, the reason why the traditional collision detection algorithm is not applicable is: firstly, the collision detection algorithm focuses more on whether the object under test is invaded as a whole, while this subject focuses more on the detection of the mating surface; secondly, the collision detection algorithm adopts The bounding box technology needs the complete surface configuration of the assembly as the basis. By constructing the bounding box to approximately replace the assembly configuration, not only the time consumption of the algorithm is related to the accuracy of the bounding box, but also the accuracy can only reach a low level. The surface of the object is often relatively flat macroscopically, but still irregular microscopically, and requires high precision; and collision detection focuses on whether intrusion occurs, and this subject not only requires the rigid body assumption, but also needs to find the matching surface on the basis of collision. The state of geometric equilibrium, which in turn provides the basis for calculating the overall size of the assembly

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