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STATION BREAK -- VOL. 4 NO. 6 JUNE 1992

HOUSE DEFEATS MEASURE TO KILL STATION FUNDING

        The House voted 254-159 last month to defeat an amendment that
would have killed Space Station Freedom's fiscal year 1993 budget of
$2.25 billion.

        The full House vote came after Rep. Tim Roemer, D-Ind.,
introduced an amendment to nix funding for Freedom from the overall
NASA 1993 budget.  Explaining his reason for introducing the
amendment, Roemer said he thinks the $2.25 billion would be more
wisely spent by adding $1.1 billion of those funds back into other
NASA programs and putting the remainder toward reducing the deficit.

        The majority of representatives, however, voted to support the
Freedom program and against the Roemer amendment.

        Rep.  George Brown, D-Calif., said, "The gentleman from
Indiana made some statement about the fact that later, in better
times, we might come back and rebuild [the space station].  We might,
but I can assure him that there will already be other space stations
up there, and there will not be much impetus for the United States to
put one up because Japan and Europe, either separately or together,
along with the Russians, and perhaps other nations, will have their
own space stations up there.  The United States will forever have lost
the image of being a world leader in space."

        Besides citing the loss of American leadership in space, Brown
and Rep. Jim Sensenbrenner, R-Wis., said the United States must abide
by its agreements with the station's international partners -- Japan,
the European Space Agency and Canada. The European Space Agency
already has spent $1.5 billion of its $4.5 billion commitment, for
example.

        "This amendment breaks the word of the United States of
America to the international partners who have committed literally
billions of dollars to fund their share of the international Space
Station Freedom. If we unilaterally pull the rug out from underneath
the space station, their billions of dollars of investment, based upon
their faith in America keeping its word, will go down the drain,"
Sensenbrenner said.

        "This is the fourth vote in the House on Space Station
Freedom. I hope it is the last one, because if we make a decision, we
ought to stick by that decision and go ahead," he added.

        Defending the scope of the space station's influence over
technology advancement, Rep. Marilyn Lloyd, D-Tenn., said, "Space
Station Freedom should be understood as a contributor to our economic
future and our technology base.  Incorporating the most advanced
technologies and materials is the key to future stability of our
economy.

        "The experimental platforms on Space Station Freedom provide
the type of environment that is conducive to researching and producing
materials that will advance our industrial base into the 21st
century," she said.

        "Our space program is yielding a nine-to-one return on our
investment."


GOLDIN TOUTS STATION'S PURPOSE BEFORE HOUSE VOTE

Editor's Note: This is an excerpt from NASA Administrator Daniel S.
Goldin's speech to the American Institute for Aeronautics conference
on April 28 in Washington, D.C.

        Our work on Space Station Freedom with Europe, Canada and
Japan will open up a whole new world of cooperation.  We can do more
together with a shared vision than is possible acting alone.  I soon
intend to reach out to visit our partners in this great adventure and
start a dialogue on how we can explore Earth, the solar system and the
universe together.

        When we plan what NASA will do year-to-year, we need to
consider where we want to be, not next year, but in 50 years, 100
years -- yes, even 500 years.  I don't know about you, but in 500
years, I want one of my successors to be able to turn over the keys of
a spacecraft to a Captain Kirk or Picard to go find out if anything is
orbiting Alpha Centauri.

        To those who say Apollo was a one-shot deal, never to be
repeated, that we've got problems to solve here on Earth, I say: Right
now we risk making the same mistake as the Chinese emperors over 500
years ago.  Some of you might know this story.  Consumed by other
priorities at home, they banned further exploration of Africa, made
leaving the country a capital offense, and burned their fleet to
ensure such "wasteful" exploring would never happen again.  Instead of
spreading its culture and influence, China turned inward, leaving the
exploration of Africa and the Americas to Columbus and other
Europeans. All this is my way of saying: we cannot pretend the
decisions we make today don't have historic consequences for the
future.

        July 20, 1989 was a historic day.  For on that 20th
anniversary of humanity's greatest accomplishment, President Bush
said, "The Apollo astronauts left more than footprints on the moon;
they left some unfinished business.  America's ultimate goal was not
to go there and go back, but to go there and go on." For the first
time in decades, we are fortunate to have a president and vice
president who personally support a vigorous space program . . .

        The primary purpose of Space Station Freedom is to be the
premier outpost in humankind's efforts to learn how to live and work
in space.  The time our astronauts have spent in space is but a blink
of an eye -- a tiny fraction of what we'll need to know to start a
permanent presence off good old terra firma.  How will the body take
the stress of zero-G?  Prolonged hazardous radiation?  Long stretches
of isolation in cramped quarters?  How do we assemble hardware?  Dock
and rendezvous?  And what about how dexterity will be affected after
long periods of zero- or partial-G?  Will astronauts have the strength
and agility to respond in life-threatening situations when a rescue is
required?  All this must be learned before we can ever go back to the
moon and go on to Mars. And the only place to learn is a space
station.


ASTRONAUTS WOW THE WORLD WITH SPACE WALKS

        NASA's Space Shuttle Endeavour crew captured the imaginations
of millions worldwide during last month's unprecedented mission of
firsts.

        This mission "brought the magic back to our space program,"
said NASA Administrator Daniel Goldin. "It represented the best in us
all."

        It was Endeavour's maiden flight, the first time four space
walks were performed on a single Shuttle mission, the first time three
astronauts squeezed into a two-person airlock and then worked together
to save a commercial satellite, and the largest (volume- wise)
assembled fixture ever built in space.

        Not only did the successful capture, repair and then
deployment of Intelsat's crippled 4 1/2 ton satellite mark a number of
firsts, but the Space Station Freedom- related space walks will yield
priceless space-based construction information, said Mike Hawes,
manager, Utilization and Operations Office, at the Space Station
Freedom Program Office in Reston, Va.

        One of the key elements of the evaluations was to quantify the
logistics, workload and timing of specific assembly sequences.  The
demonstrations were slower than expected based on underwater training,
pointing to a need for the evaluation of assembly concepts in orbit
before Freedom construction begins, Hawes said.

        Known as the Assembly of Station by Extravehicular Activity
Methods (ASEM), this 7 hour and 45-minute space walk, performed by
mission specialists Kathy Thornton and Tom Akers, and the analysis
following, will evaluate assembly and mass handling techniques
proposed for space station assembly.  The ASEM portion of this mission
was shortened by a day because of the unexpected difficulty with
capturing Intelsat. The ASEM hardware was designed and developed by
McDonnell Douglas Space Station Division for NASA's Johnson Space
Center in Houston.

        Thornton and Akers began their mission by completing
construction of the ASEM truss, which was partially built the day
before to support the Intelsat capture.  The pyramid-style truss was
built to emulate the station's pre-integrated hexagon-shaped truss.
The two astronauts attempted to dock the simulated truss section to a
pallet on the end of Endeavour's robot arm.  This simulated the
installation of crew module nodes to Freedom's truss structure.

        The crew also demonstrated one of the candidates for the space
walker self- rescue equipment, known as the crew propulsive device.
"Watching it on television, it seemed to go well.  Tom Akers was able
to translate himself and move around well," Hawes said.

        Lessons learned from these flight demonstrations, which were
recorded on film and video tape, will help station engineers
choreograph the best assembly techniques for Freedom. Engineers will
scrutinize the film, collect feedback from the crew, as well as other
data and then make specific recommendations from there, Hawes said.

        Besides the ASEM activities, which will teach designers a
great deal, the Intelsat- capture and repair has provided a wealth of
information, Hawes said. "We've learned so much about mass handling
and the other Intelsat-related trials and tribulations that we'll be
able to better prepare for, and hopefully avoid, these type problems,"
he said.

        During an interview on a Sunday morning talk show, Capt.
Daniel Brandenstein, Endeavour's commander, said, "There are things we
learned on this mission that we're going to bring back and wrap into
the [Space Station Freedom] program relating to that environment."

        "Some of the big lessons we learned are that you have to move
big masses very slowly and carefully; you have to have good handles on
them so space walkers can get a good grip; you have to have good
positioning for him or her, because you're not very mobile in the
spacesuits, and you have to have good foot restraints so they can
interact with their base, which, in this case, is the Shuttle. These
are the types of things we are looking into."

        Brandenstein pointed out that the space station already is
being designed as 'user-friendly'. "Interestingly enough," he said,
"the truss is being designed so we don't have as much busy work, for
lack of a better term.  Engineers are designing a pre- integrated
truss that will make our job much easier."


SPACE STATION FREEDOM CHIEF SCIENTIST SPEAKS OUT

Editor's note: This is a question and answer interview with Space
Station Freedom's new chief scientist, Dr. Robert Phillips.

Q: Now that you have been here for a few months, what do you, as chief
scientist, perceive as Space Station Freedom's purpose?

A: To me the primary purpose is to conduct science.  In that regard, I
find it difficult to separate science from technology.  Whether the
information comes from NASA's Office of Commercial Programs, the
Office of Space Science and Applications, or the Office of Aeronautics
and Space Technology, there will be a wealth of new knowledge that can
be used by all realms of science and technology.  It's hard to predict
all the many benefits we will derive from research aboard Freedom; I
don't think it's possible to pinpoint specific spinoffs.  However, I
know that all of science and humanity will benefit.  At no time in
history have we had this kind of an opportunity to learn, to study, to
conduct research away from the Earth's surface.

                I see Space Station Freedom as the next logical
platform in the continuing exploration of our solar system.  We need
to learn to live and work for long periods of time, continuously,
before we can move to a lunar outpost and then on to Mars. We can't
gain that kind of information from Space Shuttle flights alone, and
there's not enough data from the Russians for us to come to any
conclusions about how to live and work in space in a productive way.
We have to find out how well we can survive on a long journey, how
much work we can expect from a crew, as well as how they will fare
when they return to Earth.

Q: Speaking of a lunar exploration, why doesn't NASA just skip Space
Station Freedom and build a colony on the moon?

A: That is always an appealing idea, but to me, a major benefit of
Space Station Freedom is the ability to study the effects that
near-zero gravity has on organisms.  It is fascinating that all
organisms, from prokaryote bacteria which are the very simplest form
of life, through all of the plants and animals that have been studied,
react to the weightless environment.  We have no idea how the apparent
lack of gravity affects their chemical balances, their structure and
behavior.  To more directly answer your question, Freedom and its
centrifuge facility will be able to provide our first experience in
studying the effect of moon-simulated gravity on plants, and animals,
including mammals.  It seems to me that knowledge of chronic effects
of that type will be invaluable to moon colony planners when they
begin to consider placing humans on the moon for long stays in a
colony type situation.

Q: What do you see as your role as chief scientist?

A: I want to enhance the perception, to the broad
scientific/engineering community and the lay public, that Space
Station Freedom will do good, solid science.  From my point of view,
any science done well will benefit humanity.  It is my firm personal
belief that all good science, no matter what discipline, will benefit
all.

                Although my training is as a life scientist and a
veterinarian, I am, for example enriched by planetary exploration and
astronomical observations.  In turn, those physical scientists will
benefit from what we learn about life processes aboard Freedom. In my
view, that philosophy cuts across the entire spectrum of science,
engineering and technology.

Q: Which fields of science will benefit from Space Station Freedom?

A: Materials science, life science, as well as the planetary sciences
will benefit from research aboard the space station.  We now have four
external ports for scientists to attach payloads to the station's
truss outside of the pressurized volume.  This will greatly expand our
ability to conduct a variety of experiments related to the low Earth
orbit environment.  Microgravity scientists and life scientists will
benefit because they will have longer periods of time to conduct
experiments.  For example, microgravity scientists will be able to
study protein crystal growth to better understand their structure, and
life scientists will be able to grow plants from seed to seed -- to
study biological development.  On Freedom there will be more power and
more rack space available to researchers than ever before; this will
greatly increase the flexibility and productivity of the station.

Q: Is the process of getting a payload aboard Space Station Freedom
too bureaucratic and too cumbersome for non-NASA payload investigators
to use?

A: NASA is working hard to facilitate ease of an investigator's
integration into the system and through the process, so that science
will be easy to accomplish.  Since coming on board I have been closely
involved with the Customer Support Team from the Office of Space
Flight. Speed of integration and ease of access is a paramount concern
of this group; we want to make flying an experiment on Freedom a
productive and positive experience.

Q: Why are there several science communities fighting Space Station
Freedom funding?

A: I think people in those communities don't realize what they will
gain individually and collectively from the kind of science that will
be done on Space Station Freedom. One of my responsibilities as chief
scientist is to act as an information source to the science community
as a whole and particularly to those societies who have a negative
outlook or are operating from an uninformed basis.  We want to educate
and inform them about about our goals and aspirations and how they
will benefit from this new knowledge that will be acquired.  I have
already spoken to several groups and individuals who have concerns.  I
am eager to talk to organizations and societies who have questions
about the space station and its benefits.  I will speak to any group,
society or organization who would like to know more, so that they can
come to an informed decision about potential benefits from the science
and technology that will result from the operation of Space Station
Freedom.

Q: Why is the centrifuge facility important to the program?

A: The centrifuge, which under the current plan will be delivered on
the next flight after Freedom reaches permanent occupancy, is
essential for life sciences research for a number of reasons.  It will
provide a one-G control but, equally important, it will help us begin
to study fractions of gravity, such as 1/6-G that we find on our moon.
There is no way to duplicate that opportunity here on Earth. We need
to understand how the forces of gravity affect both plant and animal
organisms.  Are there gravity thresholds, or is response to gravity a
continuum?  We already know we have a problem nurturing plants to
maturity in near-zero G gravity, but we don't know what fraction of
gravity will help plants orient their roots to grow down or allow them
to develop seeds.  In space it has been difficult to study plant
development from seed to seed to seed, which is what life scientists
want to do.  You can't do much of that on a 13-day Spacelab flight.
The idea of studying fractions of gravity is important for the
Lunar-Mars mission.  The centrifuge will accommodate habitats for
plants, animals, and have special containers for cell cultures and
developmental biology.  It will be the cornerstone of gravitational
biology research.

Q: You've spoken a great deal about life sciences, what about the
other disciplines?

A: Although I've talked a lot about life sciences because that is my
background, I am a representative of all the science disciplines for
Space Station Freedom. Materials and microgravity sciences, the
environment of low Earth orbit, observational sciences to the extent
that they can be incorporated, development of new technologies,
commercial applications as well as life sciences are equally important
to the success of the station and our understanding of how to improve
life here on Earth.

Q: What must the program do to ensure good science?

A: Well, the first thing is to recruit good scientists and to involve
young people.  We need to involve people with vision; people who can
see the unique possibilities of doing research in space.

                I believe, from what I've seen in the microgravity and
life sciences divisions, that we are on the road to developing good
generic equipment that will allow a variety of science opportunities
aboard the station with minimal requirements for the development of
specialized extra equipment.  Certainly some experiment-unique
equipment will be necessary, but the basic facilities will be there.
We are not quite ready to recruit the individual investigators who
will do the first experiments, but that time is rapidly approaching.

                My greatest concern remains crew time and the
availability of the crew to conduct experiments.  For example, on
Spacelab there is usually a payload crew of four working with eight
double user racks.  On Space Station Freedom there will be 44 double
payload racks with a payload crew of two to tend to science research.
There's no way those two crew members can be experts on all the
varying experiments that will fly on the space station to the same
degree that they would be on a Spacelab flight.  Because of this, it
simply will take longer to do some of the experiments, and some of the
experiments will have to be less complex from an operator's
standpoint.  On the flip side however, we will be gaining far more
data than ever before, and we will be keeping more scientists on the
ground busy analyzing that information than ever before.  It just
means that we must learn to modify our approach to designing
equipment, as well as organizing operations and the timeline.


FREEDOM ON THE RIGHT TRACK FOR SCIENCE

        A group of experts representing the Space Station Freedom
science user community recently gave the Freedom program a stamp of
approval.

        After many months of studying NASA's plans for accommodating
space science research on Freedom and questioning agency officials
regarding a range of issues and concerns, the Space Station Science
and Applications Advisory Subcommittee (SSSAAS) concluded that the
facility will be well-suited for scientific research.

        The SSSAAS, a subcommittee of the NASA Advisory Council's
Space Science and Applications Advisory Committee, devoted many hours
to exploring the suitability of the station's design for scientific
research.  The subcommittee was created five years ago to ensure that
Freedom science users could evaluate and respond to NASA's
requirements for using Freedom, and that NASA would respond to the
science community's space research needs.  In addition, the SSSAAS
coordinates communications between its parent committee and the Space
Station Advisory Committee and maintains an active liaison with the
scientific advisory committees of NASA's international partners
(Canada, Japan and the European Space Agency).

        During its February meeting in Sunnyvale, Calif., the SSSAAS
made clear its position that Space Station Freedom provides a unique
and essential environment for the accomplishment of science.  The
Space Station Freedom program is taking positive steps to maintain and
improve the scientific potential of the on-orbit facility, the
committee said.  The SSSAAS recognizes that significant potential
exists in the current space station program for advances in scientific
and technological research, particularly in the materials, fluids,
combustion and life sciences.

        In previous discussions, the SSSAAS has identified additional
activities or resources required to correct deficiencies or
incompatibilities in designs or plans.  Space Station Freedom program
officials were attentive to concerns expressed by the SSSAAS.
Presentations and discussions at the latest meeting of the
subcommittee affirmed or clarified Freedom's capabilities to support
productive utilization in a number of areas.  The SSSAAS acknowledged,
for example, that NASA has made progress toward implementing the
capability to monitor and control perturbations in the microgravity
environment that is so critical to science users.

        Integration of the centerpiece of on-orbit life sciences
research --- the 2.5 meter centrifuge facility, including its
animal/plant habitat systems and life sciences glovebox --- is now
part of the baseline for the first phase of the space station program.

        Plans are being made to monitor and manage natural and induced
contamination in Freedom's external environment.  NASA also made
substantial progress in addressing user requirements for end-to-end
data services.  Finally, the space station program was applauded for
restoring a modest capability to support experiments mounted on the
external truss.

        The February meeting marked an important transition for the
space station science subcommittee.  Dr. Charles A. Fuller, professor
of physiology at the University of California, Davis, took over as
chairman of the subcommittee from microgravity scientist Dr. Robert J.
Bayuzick of Vanderbilt University.


NASA DEVELOPS REVOLUTIONARY ROBOT 'SENSING-SKIN'

        A team of robotic engineers at Goddard Space Flight Center in
Maryland have developed a revolutionary proximity sensor.  The new
sensor relies on an electric field to detect objects within a range of
just over one foot.  It can be built to be completely flat (less than
one-tenth of an inch thick) and is extremely rugged.  This simplifies
the application of the sensor to robot arms, spacecraft or payload
surfaces.

        Here is a scenario of how it would be used: Sitting in the
cupola, a Space Station Freedom crewmember prepares for a routine
inspection of Freedom's external structure.  The cupola commands a
sweeping view of the port-side truss structure that stretches out to
the solar arrays slowly rotating to keep pace with the sun.  The
crewmember's attention is focused on Freedom's telerobot, the Special
Purpose Dexterous Manipulator, already in position to help inspect the
truss.

        To perform the inspection, the crewmember must maneuver a
video camera, held at the end of the dexterous telerobotic
manipulator, in and about the truss section.  The dexterous
manipulator is a series of arm segments and joints, elbows as it were,
that provide the compound motions needed to perform such tasks.
Guiding the telerobot's arm from the cupola is a demanding skill
requiring concentration to avoid bumping surrounding structure and
mechanisms with the robot's elbows and arm segments.

        This new sensor technology, however, promises to make the
crewmember's task much easier.  It will enable the crewmember to
quickly and confidently maneuver the robot arm and camera in and out
of tight corners without bumping into surrounding objects.  Avoiding
collisions is an everyday part of life.  People avoid bumping into
others, change lanes on the highway, and duck under low ceilings.
Success at avoiding collisions is directly related to the sensory
input available to people through sight, sound and touch.  Our eyes,
ears and skin are our primary collision-avoidance sensors.  When
people build machines, such as robots, to move about and interact with
their surrounding world, robots also must have the sensors needed to
interact with that world.

        Space Station Freedom relies heavily on the use of
telerobotics, that is, robotic devices under the control or
supervision of a human operator.  Robots provide astronauts with
extended reach, magnified strength and, through the use of cameras and
other sensors, a virtual presence at the robot's location.  While the
robot augments the capabilities of the human operator, the operator
provides sensory and high-level decision making capabilities for the
robot.  A major concern for the human operator in any teleoperated
system is the avoidance of collisions between the robot and its
environment.  To prevent collisions, the operator is given as much
information about the work site as possible, including data from other
vision and force sensors.  Neither of these sensory modes can be used
to guarantee safe and collision-free motion.  Visual data, although
essential, is not always able to supply the operator with the right
warning of an impending collision.  This can happen because of awkward
viewing angles, inadequate lighting or obstructed views.  Moreover,
indications from a force sensor serve merely to indicate that
potentially harmful contact has already taken place.

        There are other approaches to help robots move about.  For
example, one common method is to develop a mathematical computer model
of the robot and the world around it.  This world model defines the
position and orientation of everything in the relevant environment,
and keeps track of the robot's location and position in that world.
Also, the accuracy with which objects are defined in the mathematical
model is fixed, whether the task being worked on requires coarse or
fine determination of relative positions.  The model does not provide
the operator with more accuracy as the delicacy of a task increases.
A large detailed world model, as is required for Freedom, greatly
increases computational requirements.  Thus, this approach can
significantly slow down telerobotic operations in complex situations.

        To address these limitations, the Goddard Space Technology
Division's Robotic Branch developed the new proximity sensor.  This
sensor is the product of an in-house development effort, with support
from the Space Station Level I Engineering Prototype Development
activity.

        The sensor uses a unique capacitive reflector (capaciflector)
technique to enable simple electronic elements to detect approaching
objects with unprecedented range, sensitivity and resolution, despite
being mounted against electrically grounded payloads and robot arms.
The approach is an extension of a technique used in instrumentation
systems to eliminate stray capacitance.  As an object comes closer,
the capacitive coupling between the sensor and the object increases,
resulting in increased sensitivity for accurate sensing at very small
distances (0.030 inches at 0.5 inch range).

        By assembling an array of sensors, a 'sensor skin' can be
created to provide both robot arms and payloads with an unbroken,
early-warning protective field so collisions will be avoided despite
obstructed views or unanticipated events.  Since the resolution of the
system grows more accurate at increasingly closer ranges, it can
provide precise, sensory-interactive guidance and alignment for tasks
such as docking and berthing payloads.  The operator is able to guide
the overall direction of the task knowing that obstacle avoidance is
being supported automatically.  The system can be thought of as
electric 'cat whiskers' that permit the robot to feel its way around
obstacles.  It is simple, robust, and works on a wide variety of
materials, including humans.

        This system has been routinely demonstrated to perform
collision avoidance at ranges in excess of one foot.  In addition,
orbital replacement unit mock-ups have been instrumented with these
sensors and each precisely guided into its mating interface.

        The sensor system shown here is essentially space qualifiable.
The materials and electronic components are either Mil-spec or made of
materials that have flown in space.  The sensors 'see' through flight
paint and even the stickers that are placed on flight hardware.  The
system has been inspected by safety, thermal and electromagnetic
interference engineers to ensure its suitability for long-term space
operations.

        Important technical advances continue to be made in the
sensor's development.  The capability to construct three-dimensional
terrain models of objects in the near field (one-inch range) has been
demonstrated and an electrically scanned array is in development.
This will further facilitate precision docking, berthing and robot
control; even precontact 'virtual' forces can be created to aid the
human operator.

        By making the telerobot 'smart' about its short-range
environment, the capaciflector sensor skin, coupled with the robot's
control software, can relax the burden on the operator while improving
the speed, safety and utility of telerobotic operations.  The
materials and electronic components are either Mil-spec or made of
materials that have flown in space.