Artificial gravity (AG) has long grounded science fiction spacefarers. In Stanley Kubrick and Arthur C. Clarke’s 1968 sci-fi classic, “2001: A Space Odyssey,” the fictional craft Discovery One uses a rotating centrifuge to mimic gravity. Even more recent movies like “The Martian” use this method of depicting AG.
While these films are science fiction, the idea behind their artificial gravity stems from science fact. Recently, a team at the University of Colorado Boulder developed an apparatus that uses the same concept to simulate gravity, bringing AG out of the realm of sci-fi and into this world.
From Silver Screen to CU Lab
Spacecraft with huge spinning centrifuges still only exist in the movies, but the CU Boulder team’s AG apparatus is a more practical one. It consists of a padded platform on which a subject lies. The platform then begins to rotate. Angular velocity created by the spin forces the subject’s feet to the base of the platform, mimicking the way gravity exerts force upon the body.
While it won’t allow astronauts to walk around as they would on Earth, it could fit on a space station or future Moon and Mars bases, to give spacefarers and colonizers the dose of gravity their Earth bodies need. It’s a crucial step in humans moving into space and living on planets, moons, and asteroids with considerably less gravity than Earth.
“Astronauts experience bone loss, muscle loss, cardiovascular deconditioning, and more in space,” study lead and aerospace engineer Torin Clark says. “Today, there are a series of piecemeal countermeasures to overcome these issues,” Clark continues. He’s referring to measures like riding stationary bikes, which crew members are seen doing in videos from the International Space Station (ISS).
“But artificial gravity is great because it can overcome all of [the gravitational deprivation issues] at once,” Clark concludes. There is, however, a big obstacle to overcome with this type of artificial gravity.
A Spin Study
Anyone who’s hopped on an amusement park ride that does a great deal of spinning can attest, if one turns their head while whirling round and round, a very disorienting sensation occurs. The clinical term for this is “cross-coupled illusion” (CCI). The illusion stems from a disruption of the inner ear, where the sense of balance originates.
But Clark and his colleagues may have a solution for CCI. They posit that astronauts could overcome the disorienting phenomena through conditioning. The team rounded up a group of volunteers and began testing them on the centrifuge. Unlike previous studies, however, the CU crew started slow.
Beginning at a speed of one rotation per minute, the researchers didn’t increase the spin until the subjects reported no feelings of CCI. The new approach seemed to work. After 10 test sessions, volunteers reported no disorientation while spinning at an average speed of 17 rotations per minute.
The team recently published their findings in the Journal of Vestibular Research. But ongoing studies have shown similarly positive results. When the number of sessions increased to 50, subjects could spin faster with more conditioning.
What Comes Next?
Big questions still need answering before CU’s AG centrifuge pops up on the ISS. For instance, researchers need to know how long the conditioning lasts, as well as how much AG can neutralize bone and muscle loss.
Overall, the CU team’s results look promising in the mitigation of low gravity’s adverse effects. Their findings could lead to true artificial gravity where astronauts cruise around a spacecraft as they do on Earth. Maybe one day spacefarers will jog around future spaceships like Dr. Frank Poole does in “2001: A Space Odyssey.”