Figure 3

Mechanical and metabolic results of wearing the autonomous exoskeleton. (A) Inter-subject mean exoskeletal ankle power provided by only the exoskeleton is shown (blue) throughout a single gait cycle, while carrying load. Power is normalized by body mass with standard deviation shown in translucent. For comparison, the mechanical power provided by only the biological ankle joint is shown (dashed red) in the case of fast walking without a load or exoskeleton, acquired from a reference dataset [33]. The normalized maximum mechanical power produced by the ankle while walking with a 20 kg load has been shown to increase to over 6 W/kg [23]. (B) Inter-subject mean change in mechanical and metabolic power is shown when using the exoskeleton is compared to not using the exoskeleton, with error bars denoting standard error. The increase in exoskeletal mechanical power demonstrates how much positive mechanical power is provided to the wearer by the exoskeleton. The decrease in metabolic power demonstrates the reduction in the rate of metabolic energy consumed while wearing the exoskeleton.