New Scientist reports on efforts to expand and improve on ISS science: Black sky research: Now the ISS proves its worth – New Scientist.
The article mentions the work by Japanese researcher Satoshi Iwase who has been investigating ways to use spin gravity to combat effects of long term weightlessness. Bed rest studies, which simulate many effects of weightlessness, have indicated strong benefits of a daily session on a spin table. One approach for space is a centrifuge small enough to fit into a habitat module but big enough for a person sitting on an exercise cycle. Rotation of such a short radius system could produce 2-3 Gs at the rim. This would result in a big gravity gradient from head to foot and could cause severe motion sickness. However this paper has an interesting item about this on page 22: Artificial Gravity Research to Enable Human Space Exploration – Study Group 2.2/Int. Academy of Astronautics – 2009 (pdf)
[…] such a short-radius device would have to spin much faster than the 6 rpm limit envisioned for a large continuous system, and it would produce significant Coriolis forces and motion sickness stimuli if the head is moved, at least until adaptation occurs. However, work on adaptation shows successful adaptation by most subjects to head movements even at high centrifuge angular velocities
So it appears that daily sessions in a small centrifuge on a long term space mission might be doable.
Speaking of microgravity, the Navy Research Lab has just gotten a huge, finely polish granite slab for doing air-table studies of space robotics systems:
/– Navy’s New Slab of Precision-Honed Granite–the World’s Largest–Will Improve Microgravity Studies – Popular Science
/– NRL Brings Inertia of Space to Robotics Research – U.S. Naval Research Laboratory