Design and Fabrication of Test Rig for Static Pushing and Pulling Experiments

Abstract

Muscular strength data associated with pushing and pulling forces are crucial for ergonomists to design tasks and equipment in manual materials handling. Usually, ergonomists measure pushing and pulling forces using a force gauge. Subjects participating in the pushing and pulling experiments need to grip and hold the force gauge. Additional weight from the force gauge can affect the muscular strength of the subjects, which impacts the validity and reliability of the pushing and pulling data. However, research on the design and fabrication of test rigs for facilitating pushing and pulling experiments seems to be scarce. This study aimed to design and fabricate a test rig to facilitate ergonomists and subjects in performing symmetric two-handed static pushing and pulling experiments. To develop the test rig, the researchers performed a maximum force measurement, a computer-aided design model, materials selection, a finite element analysis, a functionality test, and a reliability test. Seven subjects with a body mass of more than 120 kg participated in the validation of the developed test rig. Key findings of this study showed that the test rig could sustain the pushing and pulling forces up to 900 N, representing almost double the muscular strength of the subjects. This study concluded that the developed test rig was sturdy and helpful for facilitating ergonomists in quantifying the magnitude of pushing and pulling forces.