Investigation of a Cable-Driven Parallel Mechanism for Pressure Suit Arm Resizing and Motion Assistance

The fit of a spacesuit has been identified as a crucial factor that will determine its usability. Therefore, because one-size-fits-all spacesuits seldom fit any wearer well, and because individually tailored spacesuits are costly, the University of Maryland has conducted research into a resizable Extravehicular Activity (EVA) suit. This resizing is accomplished through a series of cable-driven parallel manipulators, which are used to adjust the distance between plates and rings built into a soft space suit. These actuators, as well as enabling passive suit resizing, could be used to actively assist the astronaut's motion, decreasing the torques that must be applied for movement in a pressurized suit. This paper details the development and testing of an arm prototype, which is used to better understand the dynamics of a more complex torso-limb system.