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Browsing by Author "Morris, Wallace"

Now showing 1 - 4 of 4
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    Effects of Back-support Exoskeletons on Task Performance and Perceived Exertion During Construction-related Tasks: Differences related to Experience
    Ojelade, Aanuoluwapo; Kim, Sunwook; Morris, Wallace; Harris-Adamson, Carisa; Barr, Alan; Nussbaum, Maury A. (SAGE, 2023-10-24)
    The effects of three Back-support Exoskeletons (BSEs) on task performance (completion time) and perceived exertion were examined during simulated construction tasks. Forty participants (20 novices) completed the tasks using no BSE and three BSEs, each with two support settings (On and Off). There were significant main and interaction effects of Experience level on both outcome measures. Using BSEs negatively affected task performance for some tasks, though these effects were smaller among experienced participants. Interestingly, using BSEs inconsistently affected perceived physical effort, possibly due to the characteristics of the tasks, BSE designs, and experience levels. These results indicate that the effects of BSE on task performance and perceived physical effort are specific to experience level, BSE designs, and task demands. Further study is needed to better understand how to generalize these results to the actual work population.
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    Effects of Back-support Exoskeletons on Task Performance and Usability During Simulated Construction-relevant Tasks
    Ojelade, Aanuoluwapo; Morris, Wallace; Kim, Sunwook; Harris-Adamson, Carisa; Barr, Alan; Nussbaum, Maury A. (SAGE, 2022-10-11)
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    Subjective Assessments of Arm-Support Exoskeletons During Simulated Static and Dynamic Overhead Tasks
    Morris, Wallace; Kim, Sunwook; Ojelade, Aanuoluwapo; Srinivasan, Divya; Smets, Marty; Nussbaum, Maury A. (SAGE, 2022-10-11)
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    Three Passive Arm-Support Exoskeletons have Inconsistent Effects on Muscle Activity, Posture, and Perceived Exertion During Diverse Simulated Pseudo-Static Overhead Work Tasks
    Ojelade, Aanuoluwapo; Morris, Wallace; Kim, Sunwook; Kelson, Denean; Srinivasan, Divya; Smets, Marty; Nussbaum, Maury A. (Elsevier, 2023-07-01)
    Arm-support exoskeletons (ASEs) are an emerging technology with the potential to reduce physical demands during diverse tasks, especially overhead work. However, limited information is available about the effects of different ASE designs during overhead work with diverse task demands. Eighteen participants (gender-balanced) performed lab-based simulations of a pseudo-static overhead task. This task was performed in six different conditions (3 work heights × 2 hand force directions), with each of three ASEs and in a control condition (i.e., no ASE). Using ASEs generally reduced the median activity of several shoulder muscles (by ∼12–60%), changed working postures, and decreased perceived exertion in several body regions. Such effects, though, were often task-dependent and differed between the ASEs. Our results support earlier evidence of the beneficial effects of ASEs for overhead work but emphasize that: 1) these effects depend on the task demands and ASE design and 2) none of the ASE designs tested was clearly superior across the tasks simulated.