Introduction and Testing of a Passive Exoskeleton in an Industrial Working Environment
Background: Commercial availability of passive exoskeletons, based on the use of springs and durable in an industrial setting, made the these devices much more accessible. However, there is limited evidence of the effect of these devices on physiological aspects, factors outside the single-task regulated laboratory environment and, discomfort and acceptance by the employee. Objective: This study aimed at evaluating the effect of a passive exoskeleton on muscle activity, kinematics and acceptance by employees on multi-task workstations on the shop floor. Methodology: Starting with an individual instruction course, nine participants were encouraged to test the device (Laevo, V2.4) during three weeks. After this period, motion and surface EMG were measured during two consecutive periods of executing daily tasks for at least 30 min (with exoskeleton and without exoskeleton). Results: Results show that RMS values were significantly higher for the Trapezius muscle with the exoskeleton (Mdn = 44.02) compared to the measuring period without the device (Mdn = 34.83, T = 0, p < 0.05, r = −.73); No differences were found for Erector Spinae and Biceps Femoris muscle activity. Participants reported significantly higher discomfort scores for the upper back/chest and thigh region with the exoskeleton (both p < 0.05, r = −.68). Conclusion: Results show high discomfort scores and no difference in lower back muscle activity possibly as a result of an inadequate amount of resistance given by the exoskeleton while bending over.