Feature-based assembly modeling and sequence generation

A feature-based model is proposed for assembly sequence planning automation . The fundamental assembly modeling strategy for a product is based on the mating features of its components. The objectives of this study are to inte grate assembly planning of a product with its CAD model, generate a correct and practical assembly sequence and establish a software system to carry o ut the planning process. A disassembly approach in assembly planning is use d in this study. The degree of freedom information between two mating featu res is used to characterize their kinematic conditions. Boolean operations of the degrees of freedom on all features of a component provides its local degree of freedom, which is used to set up the functional precedence relat ion. In some cases, where the functional precedence relation cannot be dete cted by geometric reasoning, clipping of the known 'common sense' relation is applied by a user. A bounding box checking approach is used to ensure no global collision during assembly, Furthermore, a set of criteria based on assembly feasibility, manipulability, assembly direction, cost and stabilit y is used to choose a good assembly sequence. (C) 1999 Published by Elsevie r Science Ltd. All rights reserved.