Wearable technology that alerts astronauts to dangers could one day help astronauts avoid getting lost in space, but it would require a deeper level of trust in the technology than humans currently have.
Researchers at Brandeis University in Massachusetts are developing devices that sound like mobile phones to provide a tactile ‘nudge’ that can help wearers orient themselves. Research funded by NASA shows that the pointers can help astronauts combat the disorientation, known to scientists as spatial disorientation, that comes from temporarily obscured vision, such as when flying through a layer of clouds or in zero gravity.
Lack of familiarity with terrain is the leading cause of fatal airplane accidents, often traced to confused pilots making decisions by gut feeling rather than fully trusting their instruments. These dangers also apply to space travel. When astronauts travel on Earth, they lose the vital signs of gravity that humans basically rely on to orientate themselves, resulting in the feeling of wandering in space. However, constant monitoring and interaction with automatic systems in space is essential to maintain spatial awareness and a sense of speed is important during spaceflight, especially during a controlled descent to the moon or Mars.
“Our biology did not evolve to cope with the conditions of aerospace,” Vivekanand Vimal, a research scientist at Brandeis University where he is exploring ways to train people to trust technology in space, told Space.com. “It’s not designed to deal with these strange villains that don’t exist.”
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Vibrating devices, or vibrotractors, developed by Vimal and his team provide signals through the skin to the vestibular system, a device inside our ear that tells the brain the tilt of our head and helps us keep it balanced. The parts of the inner ear are home to hair-like cells crowned by tiny structures called otoliths. When we move, gravity pulls on these structures, relaying signals to the brain about how far we are from our balance.
Previous test of moon landing simulations found participants were unable to easily adjust to changes in gravity, causing them to perceive their vehicle as straight when in fact it was significantly tilted. If it does, Vimal says new technology could overcome this limitation in human biology and be a useful way to deal with spatial disorientation, when a person loses the sense of direction, including where “up” he really is.
To see if their vibration-inducing method could work in stressful situations, Vimal and his colleagues Alexander Panic, James Lackner and Paul DiZio created a disturbing environment by strapping people into a chair-like machine programmed to tip from side to side without additional assistance. Over two days, 30 college students, blindfolded and wearing noise-canceling headsets, attempted to stabilize a “space chair” using a joystick. 10 of them received special training, 10 were strapped with vibrating devices – four on each arm, and the remaining 10 received both.
For half of the experiment, the space chair was positioned vertically to simulate Earth’s gravity and the participants could use their natural gravity cues to navigate accurately. To simulate zero gravity conditions, the participants were placed on their back while sitting in a chair, where the otoliths could no longer help determine speed or tilt. One vibrating device vibrated when the participant deviated one degree from the balance position, two deviated by seven degrees, three by 15, and all four vibrated by 31 degrees. If one drifted 60 degrees, it was considered a wreck.
“Hopefully these vibrations can replace the lost otolith signals and correct the errors that people had,” Vimal said.
The buzzing technology helped significantly but was not enough to prevent people from moving and crashing by losing control of the space chair, even for a small group that received some training, Vimal and his team found.
“Actually, the question is if you put these devices on a person, do you become one with them?” he said. “Especially when you’re confused, when you can’t even trust what’s inside your body, how do you trust these external things?”
The findings point to a deep, fundamental conflict between humans, perhaps an instinct that prevents us from fully trusting technology to protect us from harm. Participants said that although they knew and trusted vibrotractors, their gut-level responses often contradicted what the devices suggested. Vimal and his colleagues suspect that technology has introduced a sense of conflict between them that has created confusion, sometimes leading to wrong split-second decisions.
“It turns out that psychological trust doesn’t mean you’ll be able to trust the device,” Vimal said. “You’re making gut-level decisions with a joystick trying to balance them, and to build that gut-level bond you need more than just psychological trust.”
Why the participants of this study failed to overcome the conflict and allow themselves to be fully guided by the vibrotractors is still an open question. To find that out, Vimal said his team is experimenting with adding some kind of pressure signals to convey the visceral feeling of approaching a crash site.
Specific training to build a bond between people and technology so they can rely on vibrotractors when they’re confused can help, he added. This can be done by having participants achieve random, pre-programmed balance points on a space chair using a stand-alone device.
The study only looked at simulating zero gravity, so the researchers plan to follow it up with a chair experiment that simulates the gravity that astronauts would experience on the moon or Mars.
This research is described in a paper published Friday (Nov. 3) in the journal Frontiers in Physiology.