Maximum acceptable effort for connector assembly in automotive manufacturing

The manual assembly of connectors has job risk factors associated with musculoskeletal disorders including force, posture and repetitiveness. A variety of laboratory simulated connector assembly tasks, based on pilot work conducted at an automotive manufacturing plant, were studied using adapted psychophysical methods. The maximum acceptable frequency of connector assembly for six grip types was determined for various combinations of force and distances. In studies with a three-day acclimation and trials scheduled for 8-h days, 4-h trial lengths are sufficient. Distance did not influence acceptable frequency for hand/arm motions between 7 and 16 mm. There might be differences in maximum acceptable frequency for grip type, and force might affect acceptable frequency. Force × Cycle Rate (FCR) or time-weighted average percent maximum acceptable effort (TWA-%MAE) for these short duration tasks can be used for guidance.