An Integrated Design Support Methodology for Walking Worker Assembly Lines

A traditional assembly system-fixed worker line (FW) designed by assigning one operator to each workstation performing an assembly task at that workstation on the line, has some deficiencies, such as low flexibility, constant demand and difficult balancing. A walking-worker line (WW), with an assembly worker travelling with the work along the line, has several advantages over a traditional line, particularly in flexibility (in terms of product variability) and efficiency (in terms of high productivity). Despite these distinctive advantages of WWs over other type (FWs), the linear WW assembly line is not widely implemented in industrial environments. Although some preliminary works in WW line have been done, there is a lack of developed support methodologies to enhance WWs applications in industry. This research presents a development methodology based upon the synergistic application of ergonomics analysis, discrete-process simulation, and combinatorial optimization techniques to the problems of determining the optimum design for walking worker assembly line. The methodology intends to identify the levels of process parameters in WW lines which entail the improvements on both productivity and ergonomics.