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This work aims to investigate the effects of knee extension assistance during squat lifting. We hypothesize that adding an external torque to the knee joint using a soft inflatable exosuit can potentially induce a reduction in the muscular effort that extends to the posterior chain muscles. A total of 8 healthy test participants are recruited and instructed to lift a weight equivalent to 10% of their bodyweight. The muscle activities of the left and right Vastus Lateralis, Biceps Femoris, Gluteus Maximus, Erector Spinae (Iliocostalis and Longissimus) and Multifidus muscle groups were studied for baseline, non-assisted, and assisted conditions. The majority of participants (6 out of 8) demonstrated consistent reduction in the muscular effort of at least one muscle group of the posterior chain. A maximum reduction of 55% in the average muscle activity of the Multifidus muscle group is observed in one participant. Different neuromuscular adaptation mechanisms were observed among subjects that ultimately led to a reduction in lower-limb or back muscles activity. The results reveal that assisting knee extension during a lifting task has significant effects on muscle activity with benefits that extend to the posterior chain muscles. This work provides early evidence that the soft inflatable knee exosuit can be used in material handling tasks to reduce muscle effort and prevent work-related injuries.
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Effect of a Back-Assist Exosuit on Logistics Worker Perceptions, Acceptance, and Muscle Activity
Abstract—A workplace study was conducted to evaluate user perceptions, acceptance, and muscle activity amongst logistics workers wearing an unmotorized, dual-mode, back-assist exosuit prototype. Eleven workers performed a lifting/lowering task with vs. without the exosuit, while back muscle activity was recorded. They then used the exosuit while performing their actual work tasks in a distribution center before completing a questionnaire about their user experience. Worker perceptions of the exosuit were overwhelmingly positive: 100% felt the exosuit could be useful and fit into their daily job without interfering, >90% felt assisted and that the exosuit made lifting easier, and >80% felt it was comfortable and that they were free to move naturally while wearing the exosuit. Finally, the majority of workers showed reduced back muscle activity while wearing the exosuit during lifting/lowering, consistent with results from prior lab studies. Worker feedback on this prototype was then used to inform design of the HeroWear Apex exosuit.
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- Award ID(s):
- 1913763
- PAR ID:
- 10251088
- Date Published:
- Journal Name:
- Effect of a Back-Assist Exosuit on Logistics Worker Perceptions, Acceptance, and Muscle Activity
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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