We explored the feasibility of using biomechanical simulations to predict altered spinal forces resulting from wearing a back-support exoskeleton (BSE) during repetitive lifting tasks. Twenty (10M, 10F) young, healthy participants completed repetitive lifting task, while wearing a BSE (‘with EXO’) and without wearing a BSE (‘without EXO’). Spinal forces were estimated by applying the BSE torque profile to body kinematics measured in ‘with EXO’ condition, while spinal forces were simulated by applying the same torque profile to body kinematics measured in ‘without EXO’ condition. Simulated compression force was higher than estimated compression force, probably due to lower trunk flexion angle in ‘without EXO’ condition. Such differences were larger among women than among men. However, simulated shear force was comparable with estimated shear force. Future works further need to compare simulated and estimated spinal forces for different BSEs (e.g., soft BSE), asymmetric lifting tasks, and different age group.
We investigated how novices’ perception of exoskeleton usefulness changes with different types of exposure to an exoskeleton; and when the biomechanical benefits and limitations of potential exoskeleton use are presented to them. Twenty young, healthy participants completed this study. The three types of informational exposures to a back-support exoskeleton (BSE) were: (1) Information-based, (2) Virtual Reality (VR)-based, and (3) hands-on experience (lifting a box using the BSE), where users virtually and physically completed various lifting/lowering tasks set at shoulder, waist, and ankle heights in symmetric and asymmetric positions. After every trial in each exposure, perceived usefulness was obtained. Overall, perceived usefulness ratings generally varied with major task variables (load, lift height, and trunk angle). The VR-based exposure appeared to clarify the specific circumstances under which the BSE was perceived to be useful and reduced extreme biases (positive or negative) that individuals may have developed prior to trying on a BSE.
more » « less- PAR ID:
- 10470136
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Proceedings of the Human Factors and Ergonomics Society Annual Meeting
- Volume:
- 67
- Issue:
- 1
- ISSN:
- 1071-1813
- Format(s):
- Medium: X Size: p. 797-798
- Size(s):
- p. 797-798
- Sponsoring Org:
- National Science Foundation
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