A modularized contact-rule reasoning approach to the assembly sequence generation for product design

Concurrent engineering design is widely used to shorten the time needed to introduce a new product and to enhance the quality of the design of the product. However, designers seldom consider the difficulty of assembling a product's components and modules in the concurrent development process. In fact, the concept of design for assembly is not new. Planning the execution of assembly operations and selecting the assembly sequence during product development will provide designers with interrelated information of design and manufacture that help reduce manufacturing problems. The designer should realize that a reasonable assembly sequence for a product has a significant effect on the efficiency of the entire assembly process. This research focuses on the enhancement of the contact relation matrix approach to the generation of assembly sequences in a product design procedure. A systematic and efficient assembly sequence assistance procedure is proposed to generate feasible assembly sequences and to find an optimal sequence to assemble the product. Compared to the complexity of other methods, this research proposes a modularized contact-rule reasoning approach to generating assembly sequences. The general approach of this research is to (a) develop a modular method for assembly sequence planning, (b) use matrix operations to facilitate the generation of assembly sequences, and (c) generate the assembly sequence of the designed product by searching for subassembly extraction rules. The assembly sequences are then created in the form of a hierarchical structure. The results will assist designers to consider and reduce some manufacture problems in advance that might occur in the process of generation of the recommended design alternative.