Increased cognitive demands offset low-back exoskeleton advantages, research finds

In manufacturing, work-related lower-back injuries from lifting and handling dense objects relationship for astir $100 cardinal successful aesculapian bills annually successful the United States, according to information from the Bureau of Labor Statistics. Although caller ergonomic interventions specified arsenic concern exoskeletons person shown committedness successful reducing the hazard of musculoskeletal injuries, caller probe finds that the cognitive acceptable (where the wearer has ample intelligence resources disposable to accurately run the exoskeleton portion conducting their regular enactment tasks) of specified wearable robotic solutions successful the workplace whitethorn enforce newer risks connected workers.

These findings code immoderate of the captious concerns by the National Institute of Occupational Safety and Health (NIOSH) connected occupational robotics. Researchers astatine Texas A&M University and The Ohio State University person determined that accrued cognitive demands successful the workplace, often associated with caller technologies oregon automation, tin offset the mechanical advantages of wearing a low-back exoskeleton, a wearable instrumentality that is aimed to trim oregon redistribute biomechanical spine loading associated with dense manual work. These findings are published successful the latest contented of Applied Ergonomics.

The probe squad includes Ranjana Mehta, subordinate prof successful the Wm Michael Barnes '64 Department of Industrial and Systems Engineering and manager of the NeuroErgonomics Laboratory; Yibo Zhu, postgraduate pupil successful concern and systems engineering and subordinate of the neuroergonomics laboratory; Eric Weston, postgraduate probe subordinate successful concern systems engineering astatine The Ohio State University; and William Marras, prof of integrated systems engineering, neurological surgery, orthopedics, and physical medicine and rehabilitation astatine the Spine Research Institute astatine The Ohio State University.

"This is the archetypal survey looking into the encephalon arsenic a idiosyncratic was performing a lifting task wearing a backmost exoskeleton," Mehta said. "We were capable to papers the neurocognitive 'cost' of wearing an exoskeleton and place adaptation strategies adopted by users implicit clip to mitigate the cognitive risks introduced by the exoskeleton. We were besides capable to show the inferior of utilizing ambulatory encephalon imaging and connectivity investigation during this highly movement-oriented carnal task."

The squad recruited steadfast adults, some men and women with nary past of little backmost injuries, to enactment successful the survey that required extended lifting, some with and without the assistance of a debased backmost exoskeleton.

Participants attended 2 sessions, 1 league focused connected performing the lifting tasks portion wearing an exoskeleton and different league without the exoskeleton. Each subordinate was fitted with a mechanical exoskeleton attached to their thorax and legs portion they repeatedly lifted a medicine shot for 30 minutes. After a akin magnitude of remainder break, they were past asked to execute the aforesaid task with the assistance of an exoskeleton but were besides asked to simultaneously execute a intelligence task: subtract 13 from a fig betwixt 500 and 1,000 each clip they lifted the ball.

These tasks allowed the researchers to measurement spinal load utilizing precocious EMG (electromyographic)-assisted biomechanical modeling and show functional encephalon activation during the task utilizing an ambulatory encephalon imaging instrumentality called functional near-infrared spectroscopy. Integrating accepted biomechanical/ergonomics and ambulatory neuroimaging techniques allowed them to measure the neuroergonomic acceptable of human-exoskeleton interaction.

The results amusement that the exoskeleton did not importantly trim spinal compression loads and had a marginal applicable payment successful reducing spine shear loads, compared to not wearing an exoskeleton. However, the "cost" of wearing the exoskeleton was captured via the neuroergonomic assessment. Compared to the nary exoskeleton condition, the usage of exoskeletons during lifting recruited further regions of the encephalon that are typically progressive successful regulating alertness and vigilance.

The survey besides recovered that erstwhile each idiosyncratic was tasked with solving a mathematics occupation to travel the lifts, to simulate outer cognitive demands connected workers, they mislaid immoderate biomechanical benefits were offered by the exoskeleton successful the archetypal place.

"Cognitive demands person been shown to exacerbate spinal loading during lifting. That these demands wholly offset the tiny mechanical vantage of the exoskeleton is simply a singular uncovering of the study," Mehta said. "We wanted to shed immoderate airy connected however the usage of an concern exoskeleton impacts the worker's centrifugal and cognitive capabilities, fixed that the idiosyncratic has to larn caller centrifugal strategies to enactment efficiently portion wearing exoskeletons to bash their work. A neuroergonomics approach, i.e., evaluating brain-behavior relationships astatine work, was capable to seizure cognitive risks of exoskeletons that accepted ergonomics and biomechanical measures were not capable to."

The information concludes that an summation successful an individual's cognitive effect to tasks volition hinder, and adjacent cancel out, the benefits that are associated with wearing an exoskeleton.

"We wanted to papers however the encephalon processes human-exoskeleton enactment to place imaginable grooming strategies that tin beryllium utilized to minimize the cognitive risks and enactment faster centrifugal adaptation strategies," Mehta said. "While exoskeletons clasp large committedness successful alleviating carnal loads successful the workplace, these findings tin usher the improvement of determination enactment tools for ergonomists to find when/how and during what tasks exoskeletons should beryllium utilized connected the mill level to maximize idiosyncratic safety."

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More information: Yibo Zhu et al, Neural and biomechanical tradeoffs associated with human-exoskeleton interactions, Applied Ergonomics (2021). DOI: 10.1016/j.apergo.2021.103494