Monthly Archives: April 2012

NEEMO 16 – In search of an asteroid

Welcome aboard the NEEMO 16 mission!

Destination: Asteroid, deep space

Date: 11-22 June 2012

Earlier this year I was fortunate enough to be assigned to NASA’s Extreme Environment Mission Operations (NEEMO) 16^th mission to an underwater habitat called ‘Aquarius’, which lies about 20m under the ocean and nearly 8 miles off Florida’s Key Largo coast. Over the years, NEEMO missions have been used by NASA to provide vital research and development data to support future exploration missions.

Living underwater is an excellent space analog – the crew can practice EVA (‘spacewalk’) techniques using neutral buoyancy in water, whilst Aquarius offers an environment similar to a spacecraft: confined living space, total reliance on life support systems and no option for a quick return. The crew can only surface safely after 12 hours of decompression – to do otherwise would risk severe decompression illness or ‘the bends’.

The NEEMO 16 crew comprises NASA astronaut and mission commander Dorothy (Dottie) Metcalf-Lindenburger, JAXA astronaut Kimiya Yui, Professor of Astronomy Steve Squyres and myself. In addition we will be supported by two habitat technicians who are also diving experts. The crew will spend 12 days living in Aquarius, conducting two EVAs each day. Like any space mission, there will be an experienced ground support team who will manage operations, communications and logistics from their Mission Control Centre (MCC) on dry land.

Working with DeepWorker subs - Aquarius looms in the background

The European Space Agency will also play a key role in NEEMO’s MCC thanks to the support of Hervé Stevenin - a highly experienced EUROCOM (Europe’s voice link to the International Space Station) and EVA/diving instructor at the European Astronaut Centre (EAC). Also supporting the mission will be Ben Douglas, an experienced flight surgeon from EAC’s Crew Medical Support Office.

As if the prospect of living for 12 days underwater wasn’t exciting enough…it gets better! The aim of NEEMO 16 is to simulate a future mission to an asteroid. This is the current focus for NASA’s first manned mission into deep space, venturing beyond the moon’s orbit and once more pushing the boundary of human presence in our solar system.

The Orion spacecraft will be instrumental in getting astronauts to asteroids, launched atop the Space Launch System. For the journey, which could last anywhere between 1-6 months, the crew would likely live inside a Deep Space Habitat and once there they would explore the surface using a Space Exploration Vehicle (SEV). The SEV would take astronauts close to the surface where they could perform EVAs that would involve deploying instruments and collecting samples.

Tim, Dottie and Kimiya training for NEEMO in NASA's Neutral Bouyancy Lab

NEEMO 16 aims to study some of the challenges that will be faced during an asteroid mission – how astronauts and SEVs can work together using restraint and translation tools and techniques in order to explore the asteroid surface (particularly difficult in a very low gravity environment), optimal crew size for efficiency and the inevitable communication delay that will increase with distance from Earth.

For this mission our SEVs will be simulated by two DeepWorker submersibles, piloted by fellow astronauts. The subs will be modified with a foot restraint attached to a manipulator arm, which will enable astronauts outside the SEV to hitch a ride as they explore the surface and collect scientific samples. In addition, astronauts conducting EVA will have the opportunity to wear ‘jet-packs’ (battery powered thruster packs) to move quickly and easily from one place to another. Is this beginning to sound like the best birthday present anyone could wish for? Well, I have just turned 40 so thank you, European Space Agency!!

Steve Squyres testing the 'jetpack' and translation boom

More to follow on the NEEMO 16 mission training in the build up to Splashdown on June 11th!

No molecule shall stand still!

As part of my training on the systems of the International Space Station (ISS) I have passed my ECLSS exam a couple of weeks ago at Johnson Space Center in Houston. ECLSS is the Environmental Control and Life Support System and is one of the ISS systems that the crew interacts most with. What nature does for us when we are on the planet, we have to engineer for ourselves when we are in space. Things like water or waste management are very much on our minds on Earth as well, as we realize that we might be pushing the limits of nature’s ability to support our needs. But how about something so simple as air circulation?

André Kuipers performs inspection and cleaning of Columbus ventilation systems (Credit: NASA)

If you live in a part of the world that gets warm sometimes, you might have used fans in your home to circulate air and make the heat more bearable. If your part of the world gets very warm quite often, you might even have an air conditioning system in your home for comfort. But have you ever thought of a situation in which your health, your safety and even your life may depend on a constantly functioning ventilation system?

That is the case on the International Space Station. One of the consequences of gravity that we take for granted on our planet is natural convection : we all know that warmer air rises and cooler air descends, right? That’s one of the main drivers of our weather phenomena, and it’s also the reason why the heat from radiators is well distributed in our homes.

This buoyancy-driven effect does not exist in microgravity, therefore on the ISS we resort to forced convection. A carefully laid out system of ducting, fans and grids creates a known airflow pattern that satisfies the needs of astronaut health and comfort, as well as the requirements of a number of subsystems.

For one thing, we need forced air circulation to have proper mixing of atmosphere components. Imagine what would happen if that was not the case: as crewmembers breath, they exhale CO₂-enriched air, and without ventilation the concentration of CO₂in the air around their head would increase to dangerous levels. A little bit like breathing in a bag! Also, we constantly introduce oxygen into the ISS atmosphere to compensate for crew consumption. The Oxygen Generation System (OGS) has one outlet into the cabin and we rely on inter-module ventilation to distribute oxygen it throughout the Station. Without ventilation system not only newly produced oxygen would not reach all the modules, but the pocket of concentrated oxygen formed at the OGS outlet would cause a fire hazard.

André Kuipers uses a vacuum cleaner on the Columbus ventilation systems (Credit: NASA)

Besides maintaining a homogenous atmospheric composition, the ventilation system also makes sure that all the air is circulated through a number of subsystems. Remember, for example, that we don’t grow plants on ISS, so we need dedicated components, called Carbon Dioxide Removal Assemblies, to scrub CO₂ from the Station atmosphere. And of course we want the air to flow through our air conditioning system, which not only provides cooling, but also removes the humidity produced by crewmembers’ breathing and perspiration. By the way, the condensate recovered from the atmosphere is not lost, we have a way to process it into potable water. But that’s worth a story of its own…

I’d also like to mention a safety-related aspect which might not be so obvious. The automatic fire detection capability on ISS is dependent on running ventilation: for it to work, we need to circulate air through the smoke detectors, which are typically placed in air ducts and in front of inlet grids. Should the ventilation on ISS stop, you might notice on NASA TV that crewmembers will periodically check each module for burning odour. As we are taught during training, without ventilation the crew is prime for fire detection!

Last but not least ventilation contributes to the cooling of some components. This is especially true in the Russian segment, so much so that there are strict limitations on the opening of wall panels, since this inevitably causes some disruption of air circulation patterns.

Robonaut measures airflow for the first time on the ISS (credit: NASA/ESA)

By now I’m sure you’ll agree that maintaining a nominal air flow on Station is of paramount importance. That is why crew are responsible for making sure that inlets and outlets are kept free of obstructions at all time. Moreover, cleaning of the grids and the filters is part of the regular weekend housekeeping activities.

Crewmembers are also periodically asked to perform a measurement of the velocity field in front of outlet grids, so that experts on the ground can infer information about the health of the ventilation system. I’ll admit, it’s a bit of a tedious task, but also one that requires precision and a steady hand. That’s probably why it was the very first actual task that Robonaut 2 had a chance to try on-board a few weeks back. Who knows, by the time I get to ISS myself, R2 might have taken over this duty completely. Way to go, R2!

Robotics

A fantastic robotic duo: every time I train in the Soyuz simulator, I wish I had R2D2 to help me with my flying, and C3PO to help me with my Russian…

As an avid Science fiction reader, the word robotics used to remind me of two things: Isaac Asimov’s literary universe (with the famous 3 laws that he created), or the wonderfully conceived duo of C3PO and R2D2, made famous by Star Wars (contrary to a common belief, not all astronauts are fans of Star Trek…).

the CanadArm can be in different configurations: an astronaut needs to be able to fly it in any condition.

However, that word assumed a whole new meaning to me shortly after starting training as an astronaut, 2 years ago. My first encounter with the world of robotics has a name: B.O.R.I.S. This robotic arm only exists in the virtual world of computer based training, and all astronauts train initially on this simplified version of a real robotic arm to understand how to safely and successfully operate one.

As a test pilot, I am somewhat used to operate machines of different natures (well, somewhat different). So I felt ready to “fly” the arm using its hand controllers: but to my surprise, I learned that there’s a lot more than meets the eyes when we talk about robotic arms. Even on a simple arm like B.O.R.I.S., procedures are laid out to prevent possible problems (the most catastrophic ones being inadvertent contact with payloads, structures, crewmembers) and training is required to learn the “mental gymnastics” required to understand the motions of the arm. The stakes are higher, and so are the risks, when operating an infinitely more complex robotic arm like the SSRMS – commonly known as CanadArm.

Karen and I training in the JSC "cupola" facility for robotic operations.

Consequently, the training is also a lot more complex. But what is this “mental gymnastics” I mentioned? When we train to fly the Canadarm, as in space, we usually don’t have a direct view of the area of operations: we have to use cameras that give us only a partial view of the environment and the arm itself. Any image on a screen is two dimensional, so we use three different views at the same time to try and understand the spatial environment: but since the cameras are looking at the arm from different directions, the arm will move differently in each picture.

Most times, the operator will not be co aligned with the arm: when he gives a “forward” command, for example, the arm may move left or right on the screens. The arm may also be in an upside-down configuration, where the motions will also be reversed… and so on. Since our hand controllers give inputs for translations (left, right, forward, backward) and rotations (pitch, yaw, roll), an astronaut needs to be capable of foreseeing the end result of his commands, regardless of the arm’s configuration.

I Robot? Sometimes reality beats fiction, and robots like Robonaut may in the future help with space exploration (but only after I fly to Mars!).

Other difficulties come from the sheer dimensions of the arm: at about 50 feet length, any inputs will be greatly amplified when the arm is extended. So we train to fly as smoothly as we can (unlike flying military jets, where the motions can be very aggressive!) to avoid dangerous oscillations.

All in all, it takes over a month of intense training to qualify as an operator to fly the Canadarm.