Compression under a mechanical counter pressure space suit glove.
BACKGROUND
Current gas-pressurized space suits are bulky stiff shells severely limiting astronaut function and capability. A mechanical counter pressure (MCP) space suit in the form of a tight elastic garment could dramatically improve extravehicular activity (EVA) dexterity, but also be advantageous in safety, cost, mass and volume. The purpose of this study was to verify that a prototype MCP glove exerts the design compression of 200 mmHg, a pressure similar to the current NASA EVA suit.


METHODS
Seven male subjects donned a pressure measurement array and MCP glove on the right hand, which was placed into a partial vacuum chamber. Average compression was recorded on the palm, the bottom of the middle finger, the top of the middle finger and the dorsum of the hand at pressures of 760 (ambient), 660 and 580 mmHg. The vacuum chamber was used to simulate the pressure difference between the low breathing pressure of the current NASA space suits (approximately 200 mmHg) and an unprotected hand in space.


RESULTS
At ambient conditions, the MCP glove compressed the dorsum of the hand at 203.5 +/- 22.7 mmHg, the bottom of the middle finger at 179.4 +/- 16.0 mmHg, and the top of the middle finger at 183.8 +/- 22.6 mmHg. The palm compression was significantly lower (59.6 +/- 18.8 mmHg, p<0.001). There was no significant change in glove compression with the chamber pressure reductions.


CONCLUSIONS
The MCP glove compressed the dorsum of the hand and middle finger at the design pressure.
Waldie
James M A
JM
University of California, San Diego, CA 92103, USA. jwaldie@ucsd.edu
Tanaka
Kunihiko
K
Tourbier
Dietmar
D
Webb
Paul
P
Jarvis
Christine W
CW
Hargens
Alan R
AR
D000328:Adult; D000337:Aerospace Medicine; D001274:Atmospheric Pressure; D004867:Equipment Design; D006804:Ergonomics; D005069:Evaluation Studies as Topic; D018478:Extravehicular Activity; D017575:Gloves, Protective; D006225:Hand; D006801:Humans; D008297:Male; D011312:Pressure; D013026:Space Flight / Q000295:instrumentation*; D019442:Space Suits; D014893:Weightlessness