TransHab program has been discontinued. The following article is for
TransHab configuration on the International Space Station.|
The TransHab inflatable
module was a concept proposed as a crew quarters for the International
Space Station. The concept was tested but not chosen as a potential
Station crew quarters, and NASA at present is no longer pursuing
the concept. This section provides a historical overview of the
concept, however. The concept for TransHab originated at NASA's
Lyndon B. Johnson Space Center, Houston, Texas, in 1997 as a possible design for an inflatable living quarters on future Mars-bound spacecraft.
The TransHab, a design
concept, could provide a large volume habitation module for the
International Space Station while demonstrating its use for future
transit spacecraft. The TransHab would be an inflatable living quarters
as opposed to the more conventional space cylinder originally planned
for the habitation module.
of inflatable structures may find uses in future space exploration
beyond Earth orbit, for interplanetary spacecraft or as the ultimate
“mobile home” on the Moon or Mars. In addition to benefits for the
space station, a concept like TransHab may provide a valuable test
of technologies that pave the way to the future in space. And, as
happened in over 30,000 past space technology “spinoffs” generated
since the 1960s, the development of innovative inflatable technologies
for space may also find commercial uses on Earth that enhance lives
and benefit the economy.
by the Numbers|
(12,000 cu. ft.)
TransHab would be a unique
hybrid structure that combines the packaging and mass efficiencies
of an inflatable structure with the advantages of a load bearing
Inflatable Shell -- TransHab's inflatable shell consists
of multiple layers of blanket insulation, protection from orbital
and meteoroid debris, optimized restraint layer and a redundant
bladder with a protective layer.
With almost two dozen layers,
TransHab’s foot-thick inflatable shell is a marvel of innovative
design. The layers are fashioned to break up particles of space
debris and tiny meteorites that may hit the shell with a speed seven
times as fast as a bullet. The outer layers protect multiple inner
bladders, made of a material that holds in the module’s air. The
shell also provides insulation from temperatures in space that can
range from plus 121 degrees Celsius (plus 250 degrees Fahrenheit)
in the Sun to minus 128 degrees Celsius (minus 200 degrees Fahrenheit)
in the shade.
The key to the debris protection
is successive layers of Nextel, a material commonly used as insulation
under the hoods of many cars, spaced between several-inches-thick
layers of open cell foam, similar to foam used for chair cushions
on Earth. The Nextel and foam layers cause a particle to shatter
as it hits, losing more and more of its energy as it penetrates
Many layers into the shell
is a layer of superstrong woven Kevlar that holds the module’s shape.
The air is held inside by three bladders of Combitherm, a material
commonly used in the food-packing industry. The innermost layer,
forming the inside wall of the module, is Nomex cloth, a fireproof
material that also protects the bladder from scuffs and scratches.
TransHab configuration on the International Space Station.
Structural Core -- Made from lightweight carbon-fiber composite
materials, the central core is a hard tunnel with a shell interface
that provides three floors and dividers between various compartments.
A center passageway runs the length of the module, providing access
to all levels. The flooring and dividers are unfolded and extended
after the module is inflated. An integral water storage tank wraps
around the middle level's crew quarters to provide protection from
solar radiation storms when needed. Some areas of the floor are
open as passageways between levels, creating a roomy atrium effect.
A pressurized docking cone consists of a common berthing mechanism
and hatch, interior hatch, and an interior bulkhead.
Tunnel -- A bottom tunnel houses compressed air tanks used
for the initial inflation of TransHab as well as other exterior