Work Physiological-Biomechanical Analysis of a Passive Exoskeleton to Support Occupational Lifting and Flexing Processes

BACKGROUND Industrial tasks that are characterized by high loads, a high repetition rate, and/or awkward body postures, put employees at higher risk to develop work-related musculoskeletal disorders (WRMSD), especially low back pain. To counteract the prevalence of WRMSD, human-robot interaction could improve the power of a person and reduce the physical strain. For the lower back, a reduction of spinal loading could be helpful. The passive upper-extremity exoskeleton Laevo® is developed to support physically heavy work: it supports the back during bending and should, consequently, result in less low back pain (Laevo®, the Netherlands). OBJECTIVES The primary aim of this study is to assess to what extent wearing the exoskeleton changes: * muscular activity of the erector spinae and biceps femoris muscles; * knee compression force; * posture of the upper and lower spine, trunk, hips and knees; ...in different tasks (static vs. dynamic), different trunk postures (trunk flexion vs. trunk flexion and rotation) and different knee postures (straight vs. stooped). Secondary aims of this study are to assess to what extent wearing the exoskeleton changes: * muscular activity of the trapezius descendens, rectus abdominis, vastus medialis and gastrocnemius medialis; * perceived discomfort; * heart rate; * internal loadings on the spine, using a lumbar spine model; * the performance of subjects during functional activities (e.g., stair climbing) when wearing the exoskeleton (either turned on or off); ...in different tasks (static vs. dynamic), different trunk postures (trunk flexion vs. trunk flexion and rotation), different knee postures (stoop vs. squat), and different static holding positions(0° vs. 30° vs. 60°) with different weights (0kg vs. 8kg vs. 16kg).