Effects of the Auxivo CarrySuit occupational exoskeleton when carrying front and side loads on a treadmill

Low-cost exoskeletons can effectively support workers in physically demanding jobs, but most such exoskeletons have been developed to support repetitive lifting or uncomfortable static postures. Very few low-cost exoskeletons have been designed to support walking while carrying heavy objects, which would be beneficial for jobs such as moving furniture and warehouse work. This paper thus presents a single-session lab evaluation of the Auxivo CarrySuit, a low-cost upper-body exoskeleton designed for carrying objects that would normally be held with the arms. Twenty participants carried four loads (box or two bags, 20 or 40 lb total weight) for 2 min each on a treadmill with and without the CarrySuit. Across all loads, the CarrySuit significantly reduced the mean electromyogram of the middle trapezius (partial eta-squared = 0.74 - from 16.1% to 8.8% of maximum voluntary contraction value) and anterior deltoid (partial eta-squared = 0.26 - from 3.0% to 1.1% of maximum voluntary contraction value) with no corresponding increase in lower back muscle activation. Furthermore, maximum heart rate and Ratings of Perceived Exertion were also reduced by the CarrySuit, and discomfort was shifted from the upper body to the legs. While arm EMG was not measured, it is likely that it was also reduced due to the unloading of the arms. The CarrySuit can thus be considered beneficial in the short term, though longer-term evaluations with actual workers are needed to determine practical benefits.