A model for measuring products assembly complexity

Abstract

Abstract Complexity is generally believed to be one of the main causes of the present difficulties in manufacturing systems. In this article, product assembly complexity is defined as the degree to which the individual parts/subassemblies contain physical attributes that cause difficulties during the handling and insertion processes in manual or automatic assembly. A product complexity model has been developed by incorporating the information amount and content, as well as the Design For Assembly (DFA) principles for assembled products into an earlier model that was designed for measuring complexity of machined parts. The new model is used to assess the assembly complexity of individual parts using an index for measuring the complexity. Individual indices for parts are aggregated to obtain an overall measure for total product assembly complexity. The new measure accounts for the different parts' assembly attributes as well as their number and variety. An automotive piston and a family of three-pin electric power plugs were used to demonstrate the proposed approach for automatic and manual assembly, respectively. The impact of assembly attributes on product assembly complexity was also tracked. The proposed metric is a useful decision support tool for designers to reduce potential product assembly complexity and associated cost. Keywords: productsassemblycomplexitymetrics