Mechanical counter-pressure vs. gas-pressurized spacesuit gloves: grip and sensitivity.
BACKGROUND
An elastic mechanical counter pressure (MCP) glove for spacesuits is under development. In this study we compared handgrip and pinch grip strength levels for the MCP glove and the current extravehicular mobility unit (EMU) gas-pressurized glove.


METHODS
We employed handgrip and pinch grip dynamometers to assess strength levels and von Frey monofilaments to evaluate hand sensitivity. Tests were conducted with the gloved hand inserted in an evacuation chamber at 200 mmHg below atmospheric pressure to simulate conditions in space.


RESULTS
Average bare hand strength was 463 N and decreased to 240 N for EMU and 250 N for MCP. Pinch grip and key grip testing showed no difference among conditions. However, there was a significant decrease in palmar grip strength from 111 N barehanded to 67 N in both gloves. Barehanded endurance time was 160 s and dropped to 63 and 69 s for EMU and MCP, respectively. Sensitivity was significantly better for MCP compared with the EMU.


CONCLUSIONS
The MCP glove improved hand sensitivity when compared with the EMU glove and performed as well as the EMU glove in terms of overall handgrip strength, endurance at 25% of maximum handgrip strength, pinch grip, palmar grip, and key grip tests. Improvements in fabric composition and glove design may further improve ergonomic and other functional parameters of the MCP glove.
Danaher
Patrick
P
University of California, San Diego, Department of Orthopedic Surgery, San Diego, CA 92103-8894, USA.
Tanaka
Kunihiko
K
Hargens
Alan R
AR
D000328:Adult; D000337:Aerospace Medicine; D001274:Atmospheric Pressure; D004867:Equipment Design; D017575:Gloves, Protective; D005676:Gravity Suits; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D013026:Space Flight; D019442:Space Suits