For auto-body product, assembly dimensional quality evaluation using tolerance analysis method is a challenging task because there are plenty of elements impacting on the variation stack-up and propagation during asse...For auto-body product, assembly dimensional quality evaluation using tolerance analysis method is a challenging task because there are plenty of elements impacting on the variation stack-up and propagation during assembly process. Traditional method of dimension chain generation based on tolerance charting technique can not suit the case of auto-body assembly. This paper proposed a method to generate dimension chain based on developing a jot chain model of assembly, which can be integrated with important information needed for variation analysis, such as joints types and assembly sequences. The implementation of such a procedure will contribute to rapid evaluation of body dimensional quality in the design stage.展开更多
A method of 3-D measuring fixture automatic assembly for auto-body part is presented. Locating constraint mapping technique and assembly rule-based reasoning are applied. Calculating algorithm of the position and pose...A method of 3-D measuring fixture automatic assembly for auto-body part is presented. Locating constraint mapping technique and assembly rule-based reasoning are applied. Calculating algorithm of the position and pose for the part model, fixture configuration and fixture elements in virtual auto-body assembly space are given. Transforming fixture element from itself coordinate system space to assembly space with homogeneous transformation matrix is realized. Based on the second development technique of unigraphics(UG), the automated assembly is implemented with application program interface (API) function. Lastly the automated assembly of measuring fixture for rear longeron as a case is implemented.展开更多
基金National Natural Science Foundation of China(No.50375092)
文摘For auto-body product, assembly dimensional quality evaluation using tolerance analysis method is a challenging task because there are plenty of elements impacting on the variation stack-up and propagation during assembly process. Traditional method of dimension chain generation based on tolerance charting technique can not suit the case of auto-body assembly. This paper proposed a method to generate dimension chain based on developing a jot chain model of assembly, which can be integrated with important information needed for variation analysis, such as joints types and assembly sequences. The implementation of such a procedure will contribute to rapid evaluation of body dimensional quality in the design stage.
文摘A method of 3-D measuring fixture automatic assembly for auto-body part is presented. Locating constraint mapping technique and assembly rule-based reasoning are applied. Calculating algorithm of the position and pose for the part model, fixture configuration and fixture elements in virtual auto-body assembly space are given. Transforming fixture element from itself coordinate system space to assembly space with homogeneous transformation matrix is realized. Based on the second development technique of unigraphics(UG), the automated assembly is implemented with application program interface (API) function. Lastly the automated assembly of measuring fixture for rear longeron as a case is implemented.