NEEMO 14 Topside Report No. 3, May 11, 2010
"Mission Day 2- "GO FOR EVA!"
After a busy morning of preparations for their first task-based extravehicular activity (EVA), the crew headed out of the "wetporch" and began their task at 9:30 am EST today.
Today's timeline is jam-packed, with crews performing EVAs in both the morning and afternoon, educational outreach events highlighted by our undersea rover "scuttle" and a full suite of other science tasks.
Both of the EVAs today are centered around the crew wearing our Center of Gravity (CG) rigs while performing a variety of tasks. They will conduct these tests while performing tasks on our full-scale mock-ups of the lander, rover, ascent module, airlock, tunnel and a simulated incapacitated crewman. More on these awesome mock-ups tomorrow. They are something to see!
Here are some details about the CG testing:
The primary tasks for these first days involved objectives from NASA's EVA Physiology, Systems and Performance (EPSP) Project. As on six previous missions, NASA is using this opportunity to expand an ongoing study to understand how both the center of gravity (CG) and the weight of a spacesuit affect performance when conducting exploration tasks in simulated lunar gravity. Based on data collected in these missions and other NASA studies, the NASA engineering team is in the process of refining their spacesuit design to limit the CG effects and optimize total weight.
For the CG task, the aquanauts wear a reconfigurable backpack developed by the EPSP team working in conjunction with Crew and Thermal Systems engineers. Then they perform the activities representative of lunar exploration tasks for different CG configurations, and evaluate how poorly or how well they can do each task. These tasks include: timed walks and jogs, ascending and descending a 20 degree ramp, kneeling, falling and recovering, picking up rocks, shoveling, and climbing ladders. This study includes three different CG locations currently under consideration for the new lunar suits, and for comparison, an additional CG configuration from the spacesuits used three decades ago for Apollo.
In addition to understanding the effect of CG on crew performance, we are also evaluating the importance of overall suit weight. Wearing a spacesuit that is too light may result in poor traction for performing tasks. However, if a spacesuit is too heavy, it can be tiring to even move in it, much less do any work. The same exploration tasks listed above will be performed with five different suit weights, in order to understand the interrelationships between CG and weight when performing planetary exploration tasks. This is an important consideration in the design of future spacesuits and portable life support systems.