MEK: spacewalk training without the water

What MEK is

Astronauts rehearse spacewalks in a swimming pool. The Neutral Buoyancy Laboratory is the best ground analog there is, and it is also a building full of water that requires divers, a crane, a suit technician team and a schedule booked months ahead.

MEK is Ethereal Matter's full body haptic training and simulation platform. It applies real force feedback to a person's limbs and torso, so the resistance of a hatch, a handrail or a tool is felt rather than imagined. The same hardware also covers exercise and rehabilitation, which matters once it is aboard a station where every rack has to earn its volume.

Why the Lab took it on

MEK sits exactly where the Lab works. As a prototype it was convincing, and in the usual model it was unfundable: too mature for a research grant, too raw for a procurement, stranded between TRL 4 and 6.

Carrying it across meant doing the qualification and positioning work nobody else pays for, and finding it a buyer before it is finished rather than after.

The first year

I joined Ethereal Matter in October 2025 and have spent the year since taking MEK from a working prototype in Sausalito to a platform with a federal review behind it and proposals in front of it.

NASA Marshall. MEK completed a coordinated review at Marshall Space Flight Center, across five offices. That review is the reference point every later conversation starts from.

Federal pathways. We opened the SBIR route through the subtopic managers at Marshall, and explored a non-reimbursable Space Act Agreement so NASA could evaluate the platform without money changing hands.

State capital. We tested eligibility for the Texas Space Exploration and Aeronautics Research Fund. The company is headquartered in California, so the practical route is as a subrecipient under a prime with Texas presence rather than as a direct applicant.

Primes and operators. We approached the prime that holds the human systems training scope on its NASA human health and performance work, and brought MEK to commercial station operators. Those conversations are ongoing and the counterparties are not public.

Demonstrations. Investors, operators and explorers have come to Sausalito to put the system on. The people who try it tend to become the ones who open the next door.

PaleBlue

In 2026 we joined PaleBlue, whose zero gravity engine the European Space Agency uses to train its astronauts, on a combined training system: their simulation and our force feedback in one loop, so a trainee sees the task and feels it at the same time.

What a claim has to survive

Early on we tested a claim about measuring recovery and found that standard equipment could produce the same before and after numbers. That made the claim one of convenience rather than capability, so we cut it.

The differentiator has to be something only this platform can do: applying and measuring real force across the whole body, in a volume a station can afford, with one machine covering training, exercise and rehabilitation.

Training Safer Spacewalks

We wrote the case up as a paper, Training Safer Spacewalks, and presented it at SpaceCHI 2026 at NASA Ames in September 2026.

The argument is about the pool. Water resists motion in a way vacuum does not, so some of what a trainee learns underwater is wrong enough to count as negative training. Force feedback on dry land can apply the loads a suit and a handrail actually produce, without the drag that comes with the tank.

The pool is not benign either. Suited training runs last six hours or more under water, with safety divers in attendance, and the water itself is a hazard: in 2016 a NASA astronaut's helmet took on water during a Neutral Buoyancy Laboratory run and the session was called off. On orbit the same failure nearly killed Luca Parmitano in 2013, when water filled his helmet during a spacewalk and he had to feel his way back to the airlock.

A follow-on abstract has been submitted to the NASA Human Research Program Investigators' Workshop for 2027.

Training more people than the pool can hold

Spacewalk training runs through a small number of neutral buoyancy facilities, each with divers, suit technicians, medical cover and a schedule measured in months. That capacity was built for a few government astronauts a year. It does not scale to commercial station crews, private missions and lunar surface teams arriving at once.

MEK trains the same motions with force feedback instead of water, which means a unit can sit where the crew already is: a training center, an operator's facility, a clinic. The constraint stops being pool time and becomes how many units exist.

The same hardware covers the work inside the vehicle as well as outside it. Inboard tasks are where most crew hours actually go, from maintenance and stowage to medical procedures, and they are rehearsed today mostly in mock-ups on the ground where nothing resists the hand. Force feedback lets both be practised in one place, by people who are not career astronauts.

Where it goes next

The near term is training for the next generation of crewed stations, where the same spacewalk skills will be needed and the pool is a long way away. From here the work is the ordinary work: qualification, more trainee hours on the rig, and the evidence to show what transfers from the simulation to the suit.

Reviewed and tested with