Space station orientation

In space, what your architect doesn’t know can kill you. Squared edges might snag a life-support hose or another vital piece of equipment. The routes to escape vehicles must be clearly marked–in fact, everything must be very clearly marked, since visual cues give zero-gravity astronauts their sole sense of orientation. Then there’s the simple matter of dinner. Seating seven astronauts at an ordinary table could be fatal (and not for lack of scintillating conversation). “If you have seven people sitting around a table and they’re all exhaling,” says Garrett Finney, lead architect at NASA’s Habitability Design Center, “there’s this potential to build up [CO.sub.2] and start to suffocate everyone around. In space, there’s no natural convection, so it doesn’t rise or fall–it just stays there.”

In brief, life on NASA’s planned “habitation module” for the International Space Station would be nasty, brutish, and short were it not for the engineers and designers who create a livable environment in one that is distinctly unlivable, a place where a table is not just a table, but a piece of equipment as vital as an oxygen tank. The “hab module,” as it is called–still some five years away from deployment–is not a capsule for space flight, as are NASA’s shuttles and Russia’s Soyuz, but a machine for living: aboard the ISS, astronauts will be dwelling in space for record amounts of time.

NASA engineers are well trained in ensuring survival on short-term space flights, but the mission of the year-and-a-half-old Habitability Design Center–made up of everyone from architects to aeronautical engineers to human factor specialists–is more earthbound: to make the astronauts feel at home. This is the horizon of a new discipline, space architecture. “Because people are being sent up there for longer periods of time,” says Finney, “everyone realizes that something more than engineering solutions has to happen.” As Janis Connolly, NASA manager of HDC, describes it, the center’s goal is “putting the human factors and such in the beginning of the design process, rather than having us come into the game as these designs have already been developed.”

In general, says Finney, a Rome Prize-winning architect more accustomed to building below the stratosphere, space architecture is rife with “lots of basic stuff you never have to think about on Earth.” Color, for example, is not merely a matter of aesthetics. The case of the “local vertical” is instructive. The arrangement of equipment has to be consistent to give astronauts a sense of personal orientation. For this reason, the tops of the habitation modules will be painted off-white, while the bottoms will be in color. The color, however, cannot be so dark that it absorbs available light (which needs to be a minimum of 10 feet of candlepower at any point, notes Finney), nor can it conflict with the palette used for emergency and equipment markings (for instance, green for oxygen). Because the various modules look essentially the same, each features different colors to help provide “mental mapping.”

Earth architects take gravity for granted, but aboard the ISS, there is no “normal” body position, and the simple act of opening a kitchen cabinet–above and beyond the cabinet itself–poses a thorny design problem. “It’s like elementary high-school physics,” says Finney. “If you try to turn a switch and you’re not attached to anything, you’re just going to turn your body–it’s all equal and opposite reaction.” Hence the architects installed a variety of foot and hand restraints throughout the modules to enable personal movement and the operation of controls. Yet, like most things aboard ISS, even small conveniences are not simple. Velcro, which is commonly used on shuttle flights to attach objects to surfaces, tends to degrade overtime in the absence of gravity, says Finney, eventually shedding a powder, which on the ISS would become a part of the air system–and the astronauts’ lungs. Also, restraints, like everything aboard the ISS, must fit a wide user profile that ranges from the 5th percentile Japanese woman to the 95th percentile American male. The question then becomes, do you design an adjustable restraint, or a fixed restraint that can accommodate featherweights and heavyweights alike?

Historically, NASA has been good at designing individual pieces of technology, Connolly notes. “One of the things HDC is looking at is the overall context in which this hardware fits,” she says. “We’ve gotten away from developing the piece parts and hoping they fit later by looking at an integrated approach: How does this table relate to the window, and to the galley, and to the location of the stored food?” On Russia’s Mir and currently in the Russian service module on the ISS, the treadmill used for exercise is located near the wardroom table.

Because heat doesn’t dissipate by it self in space, the jogger ends up running in a ball of his or her own sweat. “It’s actually kind of disgusting,” Finney says. “You have little globules floating around right where you’re trying to eat.” Astronauts do require enormous amounts of exercise, though, to prevent muscle atrophy and to maintain bone density, so HDC is thinking about where to put an exercise unit on the hab module without creating a similar conflict. Complicating the issue, HDC, like NASA as a whole, must rely on simulated environments or brief experimental phases to replicate space conditions; these range from the world’s largest indoor pool, the Neutral Buoyancy Laboratory, to the (C-135, or “vomit comet,” an airplane that flies in parabolic arcs, allowing 25 seconds or so of zero gravity about 40 times in a two hour-flight.

In shaping the habitation module, the HDC must balance the social functions of architecture and design with a bewildering array of engineering and safety constraints placed upon even the smallest detail. For a table designed for the wardroom, a common area, HDC acknowledged the social importance of dining in a group. But that is where the comparison to an Earth table ends. This one, which will probably be made of aluminum, needs to be quickly removable in case of an emergency in the “rack” (NASA’s term for the standardized compartments that comprise the module’s walls, floors, and ceilings) below. It also needs to breakdown into sections so it can fit easily on the shuttle, the conveyance for the entire hab module. The table’s edge matches the standard hab module handrail so that tools and gadgets can be clipped to both spots. Then there’s the space in the middle, which Finney dubs the “accessory trough.” twill feature an air circulation system, to prevent the “asphyxiation problem,” as well as a suction acc essory, a screened sort of box over which one might eat–to prevent crumbs from drifting into the air system–or perform experiments that require a screw to stay in place. (On the Russian space station Mir, notes Finney, cosmonauts shaved over the suction box, placing a napkin to catch stubble.) And then there’s the “ladder restraint” below the table. The ascending toeholds mean that astronauts of varying sizes can easily “sit” (the space table has no chairs; astronauts assume what Finney describes as a “dead man’s float” position), as well as “torque” their bodies for comfort by quickly switching to another rung–rather than reaching under the table to undo a strap.

Some perennial space problems still need solutions–such as hygiene. HDC envisions a “Full Body Cleansing Compartment,” which may or may not be a shower. “A shower is a design solution,” observes Connolly. “The requirement is full body cleansing.” In space, of course, designing a shower is more than a matter of picking tile and a shower-head. Of primary concern is water itself. The ISS is a “water poor” environment where even urine will be treated and reused (unlike on the space shuttles, where water is generated as part of the fuel-burning process). Previous space station efforts such as the U.S. Skylab and the Mir attempted, but later abandoned, showers. “On Mir they tried to have a positive airflow that would blow the water down to the floor,” says Finney. “What happened was that the surface of the water globules would spin around but the globules themselves wouldn’t move anywhere.” Also, beads of moisture tend to be attracted to one another, as well as to the body; the water may float up to the astronaut ‘s mouth and interfere with breathing.

One side effect of the habitation module’s uniformity is that the astronauts themselves become interior design elements; the cotton clothing they wear for comfort becomes a welcome source of nonregulation color. The only other fabric surfaces are on the exterior and interior of the crew quarters and stowage bags. These are limited to two shades of NoMex, a DuPont fabric used in firemen’s coats. “Only a few colors have been approved for space flight,” notes Finney, “meaning that they’ve been sent to a lab and ignited–different dyes are differently toxic when burned.” The palette is now overwhelmingly white with some blue, but Finney hopes that areas will be set aside to accommodate personal design touches by the astronauts, ranging from family photos to, say, an Indian scarf.

But in space, as on Earth, there’s no accounting for taste. When the legendary designer Raymond Loewy employed a series of earth tones in his design scheme for Skylab, in the late 1960s, it was to make the occupants more comfortable by reminding them of their home planet. The plan backfired, Finney relates: “‘It’s drab as hell up here,’ the astronauts said. ‘We need some interior decoration.”‘

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