Parts Grouping in Mechanical Assembly Planning

Abstract

Mechanical parts must be grouped for assigning assembly tasks to assembly machines and for generating assembly sequences. Though several methods to support the parts grouping have been proposed, their applicabilities are limited within specific problem domains. This paper proposes a more general method based on the imposition of constraints with respect to grouping. First, assembly processes and constraints of the grouping are represented by out-tree structures. Based on them, two algorithms are developed. One is to generate all feasible assembly processes and groups by solving pseudo-boolean equalities and inequalities. The other is to calculate the total number of feasible assembly groups to reduce the amount of computation. An example demonstrates the efficiency of the proposed method.