Metabolic Cost Approach to Characterizing Advanced Spacesuit Mobility

Spacesuit mobility has been historically difficult to define and therefore, difficult to write requirements for.  Most previous efforts have concentrated on establishing metrics for isolated joints – often multiple movements for each joint – and characterizing the range of motion of that joint – as well as the corresponding joint torque through said range of motion.  However, there have been multiple issues with this approach:  First, it has been shown through multiple tests at JSC that joint torque data lacks repeatability, even with the same test setup and subject; Second, a suit can often meet defined mobility requirements yet exhibit lackluster or anomalous mobility behavior (or vice versa); Third, defining mobility at the isolated joint level does not capture the mobility of the comprehensive suit system in real application, with multiple joints often working in harmony or in discord.  Lastly, there lacks a standardized testing protocol with which JSC and suit contractors can assess suited mobility in a repeatable and predictable manner.  The proposal contained herein aims to mitigate all of these problems through investigating a new method of suited mobility characterization: by measuring the relative metabolic cost associated with performing a series of functional tasks as compared to performing those same tasks in a shirtsleeve environment.