Applying psychophysics to prevent overexposure: On the relationships between acceptable manual force, joint loading, and perception

Abstract

Psychophysical methods are commonly used to establish guidelines for task acceptability or to indicate perceived task demands. Despite their widespread use and practical application, the subjectivity of psychophysical methods can limit their perceived benefit to field ergonomists and engineers. However, recent work has revealed important links between biomechanical limitations and psychophysical force acceptability and also between perceived effort and moment loading at the shoulder. These twin findings support the continued use of psychophysical methods in ergonomics, and implore future developments to improve their use in the field. Through a combination of literature review and research vignettes, these links are described, discussed, tested and applied in both experimental and simulation scenarios. Whether the goal is to design work based on psychophysically acceptable guidelines, or to gauge existing task demands using perceived effort, this paper highlights the power of psychophysics for ergonomic design. Relevance to industryThis paper describes how ergonomists can use psychophysics to prevent overexposure in the workplace. Methods relying on psychophysical load selection and perceived effort are described in the context of underlying biomechanics.