| Assembly planning, in which parts and subassemblies are put together, may significantly affect the efficiency of the assembly process and safety conditions for the assemblers. Although many experienced industrial engineers are proficient at devising efficient ways to assemble a given product, systematic procedures integrating the time measurement formula and compiled ergonomic knowledge are needed to facilitate automated design procedures and to guarantee that better and ergonomically safer assembly planning options have not been overlooked.; The three-step approach, (1) establishment of precedence constraints, (2) automatic generation of all valid assembly sequences and (3) refinement and selection of the most efficient and safe assembly sequence, is a general and applicable strategy to assembly operations. The ability to input constraints and task descriptions, generate all valid assembly sequences, report the corresponding assembly efficiency and perform ergonomic hazard level analyses provides a way to select and refine a more efficient and ergonomically suitable assembly plan in concurrent design.; This dissertation presents the conceptual structure of a strategy which integrates (1) the constraints method of automatically generating all valid assembly sequences, (2) MOST (Maynard Operation Sequence Technique), a time measurement method and task description and (3) compiled ergonomic knowledge base, into refining and selecting more efficient and ergonomically safer assembly planning in the manual assembly environment. Based on this conceptual structure, two computational systems have been developed for generating more efficient and ergonomic safer assembly plan under the MOST criteria.; The first system investigates the approach of generating more efficient assembly planning based on the constraint conditions and MOST time measurement criteria. The second system was designed to analyze assembly task descriptions under the MOST criteria to predict the ergonomic suitability level by applying compiled ergonomic knowledge.; The pathway and description for resolving, refining and selecting assembly sequences and establishing the process task which can be analyzed for ergonomic suitability are applicable to both the design and manufacturing aspects of a project. Based on this close relationship between the product and process, the design iterations and interaction with manufacturing should be faster and more frequent. |
