Design proposal of an adjustable workstation for very short and very tall people

摘要

This research presents a design proposal for extremes where men and women perform similar tasks in the same workstations. Within assembly lines hydraulic presses that allow to be adjusted to different heights are used. However, at the initial workstation of the cell production, a high fixed workstation is used. In addition, workers have to handle axis of different dimensions. For example, the shortest is 50 centimeters while the longest is 90 centimeters. Medical service department has received constant complaints from workers assigned to this workstation, which reported mostly musculoskeletal discomfort in shoulders, neck and back. The objective of this research is to develop a new workstation design that allows adjusting its dimensions according to the worker's statures and part's sizes used in the assembly lines. Ergonomic assessment was developed applying the Muscular Fatigue Assessment (MFA) and Biomechanics analysis before and after workstation implementation. The MFA method shows very high levels of ergonomic risk on shoulders, neck, back, and hands. While the biomechanical evaluation shows overload on shoulder (321%), elbow (490%), L5/S1 (518%), and hip (118%). A workstation that reduces risk levels from very high to medium is designed and also eliminates overloading in shoulder and ankle. This is confirmed by the methods of assessment after implementation of the new design workstation.