From: NOAA Aquarius Undersea Laboratory
Posted: Tuesday, July 25, 2006
Today at 10:21 am Koichi Wakata, Karen Kohanowich, Karen Nyberg, and Drew Feustel joined an elite group of people in this world who have spent 24 hours under the sea in "saturation", making them the world's 4 newest aquanauts. Mark Hulsbeck and Dominic Landucci, of course, were already experienced aquanauts. Koichi, by virtue of having flown in space and lived under the sea, becomes the 13th "aquastronaut"!
NASA is in the early phases of designing the space suit for Lunar and Mars exploration. The Apollo moon walks demonstrated that the weight and center of gravity (c.g) of the space suit and portable life support system backpack were important parameters affecting astronaut performance. To investigate the acceptable c.g. limits for future designs, the NASA EVA Physiology, Systems and Performance Project (EPSP) working in conjunction with the Crew and Thermal Systems engineers have developed reconfigurable c.g back pack that can be worn by divers on "sea walks". On Sunday the NEEMO divers weighed out at lunar gravity levels (1/6 g), donned the reconfigurable backpacks and performed a series of tasks representative of planetary exploration.
These tasks, performed under six different center of gravity configurations included: timed walks, jogs and runs, kneeling, falling and recovering, picking up rocks, shoveling and climbing ladders. The divers evaluated each of the tasks using a modified Cooper-Harper rating scale. The timed ambulation tasks will be compared to a control group performing the same ambulations using a partial gravity weight relief system at the Johnston Space Center.
This comparison will allow the data to be adjusted for the effects of water drag. The advantages of performing these tasks on saturation excursion dives include a real operational environment, unlimited time duration and the ability to investigate the full six degree of freedom work volume. For safety reasons the ground based partial gravity simulators do not allow subjects to fall down. Later this week the divers will perform the same tasks under simulated Martian Gravity conditions. They will also wear the reconfigurable c.g backpacks while performing other mission tasks. The divers will perform half of the task with the c.g currently planned for the Lunar/Mars suit and the other half with the c.g configuration that had the best Cooper-Harper ratings.
This data will be combined with c.g studies in other environments (partial gravity simulator and parabolic flight) to drive out the optimum configuration of the exploration suit portable life support system (backpack).
The Superlite 17 is a hard hat diving system, and is one of the most popular commercial diving systems in the world. For "surface" exploration tasks, it allows our aquanauts to be weighted to give a buoyancy effect like the gravity on the moon and Mars, and gives them a limited visibility helmet much like they might find in a space suit. For simplicity and safety reasons, it uses an umbilical instead of a closed-loop life support system. Note the helmet camera on top.
During these excursions, you can see and hear the live communications between our aquanaut team and the Mission Control team in Houston via streaming video at the NURC website. Scroll down to the "Diver Cam" section, and choose which diver you want to follow along with. It requires Quicktime to be installed, but will prompt you through the installation if your computer doesn't already have it loaded.
- NEEMO 10 Topside Team
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