AUTOMATED-ANALYSIS OF 3-D POLYHEDRAL ASSEMBLIES - ASSEMBLY DIRECTIONSAND SEQUENCES

Some issues concerning the automated analysis of three-dimensional (3- D) assemblies consisting of polyhedral components (that is, components with plane faces) are studied. The product is assumed to have been mo deled in a boundary representation environment. An algorithm for matin g surface identification is first developed. Noting that previously pu blished work on the automated determination of assembly directions has largely been confined to the 2-D domain, a new approach to the automa ted determination of the feasible range of assembly directions in the 3-D domain is proposed. This consists of the concept of principal disa ssembly directions (PDD) that lie on the boundary of the region defini ng all feasible assembly directions. Finally, an algorithm for determi ning the translational freedom of components during assembly is presen ted. These two algorithms enable a rapid construction of the disassemb ly tree that forms the basis for the automated generation of assembly sequences in the 3-D domain.