Precedence Constraint Knowledge-based Assembly Sequence Planning for Open-Architecture Products

This paper discusses feasible assembly sequences for Open-architecture products (OAPs). A structure diagram of OAPs and a product assembly constraint matrix are proposed to represent the precedence constraint knowledge among parts and modules. Considering that an independent functional module may not be independent in its spatial structure, a module of OAPs is first evaluated for its possibility to be assembled as a single sub-assembly. If it cannot be assembled as a sub-assembly, it will be divided into several sub-assembles or parts to adjust the product hierarchical graph. Combining with module types of OAPs, feasible assembly sequences of modules and parts are finally generated using the hierarchical precedence method. An industrial paper-folding machine is used as an example to verify the proposed method.