Space Hug: a deep pressure therapy suit for sleep in space
On Earth, gravity gives the body a constant, calming sense of being held. In microgravity that disappears, and with it a source of comfort that supports sleep and stress regulation.
Where it started
Space Hug began as an inflatable sleeping device for the Axiom space station: a deployable bed that holds a body still, wraps it gently, and keeps the air around the face clear. The garment flown on the parabolic flight took that same idea, gentle pressure across the body, and made it wearable.
The sleeping device: the problem
A factor that greatly affects the health of astronauts who inhabit any space station is the quality of sleep. Through the years of the space missions, the sleep of astronauts has been monitored, reporting sleep deficits, in particular of the REM phase, due to various factors.
The adaptation of astronauts to weightlessness in particular affects the quality of their sleep, together with the alternation of sunrises and sunsets that occur with high frequency in orbit, shifting the regular circadian rhythm.
With a view to future exploration and space tourism, it is therefore essential to plan sleep areas that promote the wellbeing of their users and occupy acceptable volumes, considering that every cubic millimetre in space is precious.
The sleeping device: requirements
- 01The device must ensure rest and comfort for the user.
- 02Given the absence of gravity, the device can be positioned vertically.
- 03The device must contain the astronaut as much as possible, so that they do not float during sleep and hit other surfaces.
- 04The device must occupy the least possible volume: an inflatable or deployable solution is recommended.
- 05The device must ensure correct recirculation of air around the user’s mouth. During sleep it is common for carbon dioxide produced by breathing to accumulate, which must be cleared through good ventilation, so the areas near the mouth must remain free.
- 06The device must comfortably embrace the user: research has shown that in space there is no longer the sensation one feels on Earth of being gently wrapped in our bed.
- 07The device must have a design in line with the design of the space station, being made for paying users who will expect a highly functional and pleasantly aesthetic instrument.
The sleeping device: the solution
The solution is an inflatable device made up of different sectors. The mattress material is breathable and light, and allows the mattress to remain inflated without air leaks while staying comfortable against the skin.
The mattress has lateral containment walls that enclose the user inside and act as a hook for the upper cover, which is also inflatable. The upper cover is made up of inflatable cylindrical sectors, covered in a comfortable material such as suede, which swell slightly to compress the upper part of the user’s body.
The inflation pressure must be such that the sectors inflate differently according to the area they cover, wrapping the person lying down without exerting pressure. A similar inflation system is used in hospital mattresses to avoid the formation of sores in patients who have to stay in bed for long periods.
The inflation system must be positioned far from the mattress, so that the noise of the compressor does not disturb the person during sleep, which means an adequate system of pipes and connections has to be worked out.
The problem
Astronauts can lose up to 42% of their deep sleep in microgravity, and many report a sensation of falling as they try to drift off. On Earth, deep pressure is a well-established way to calm the nervous system. Almost nothing was known about how it works without gravity.
The suit
Space Hug is a wearable that restores gentle, adjustable pressure of 4 to 6 kPa, the input behind weighted blankets, in an environment where weight no longer does the work. It is soft, even, built for extended wear, and fail-safe against over-pressure.
The flight
Space Hug flew in May 2024 on an Aurelia Institute Horizon parabolic flight with the MIT Media Lab and Zero-G, through lunar, Martian and zero gravity. Anastasia flew as designer and test subject, representing the AIAA Space Architecture Technical Committee, and collected first-of-its-kind data on pressure as a sleep countermeasure.
What came next
The results now inform pressure-based wearables. In August 2024 Stellar Amenities sent Axiom Space a letter of intent to supply a low-profile compression sleep garment for its commercial station, alongside a concept for an inflatable sleeping device that holds a crew member still and keeps the air around the face clear.