First NASA Reality Check

The question was asked "What is wrong with NASA?". It brought back to
me my first experience with NASA realities. I was just several years
out of college and had changed jobs to work for a military aerospace
contractor mostly because it was interesting work and secondly because
the location was just outside the gates of the Johnson Space Flight
Center in Clear Lake, TX. My dad had collected a scrapbook of newspaper
clippings of the Gemini and Apollo missions and I had grown up thinking
that NASA would be kind of an engineer's heaven. So I was looking
forward to getting into NASA conferences and meetings around the Clear
Lake area many of which are open to the public and free or I sometimes
could finagle my way in as a subcontractor even though I didn't work
directly on NASA projects.

One of the first conferences I attended was on the dry topic of
preliminary requirements analysis for Space Station Freedom assembly.
It became obvious very quickly that there was a MAJOR problem that
nobody was willing to directly discuss or even really say anything that
might hint at a problem but it was causing massive problems with station
design and assembly: the Canadian robotic arm. The Canadians had
discovered that they received lots of good publicity any time the
robotic arm in the shuttle was used and they were therefore the first to
contribute to the new space station. Of course following up on a good
thing meant that they had all ready designed and had contractors
building a new robotic arm. This had happened long before NASA had even
gotten started which meant that no requirements could be flowed down for
what the arm (if there was to be one) would need to do.

NASA, being funded by the government, is considered by government
officials to be a jobs program to be used as a tool for administration
policy. One consistent policy is to be nice to Canada. (The current
administration doesn't seem to care who they make mad so it is not
always consistent.) So there was no way that the NASA political
handlers were even going to consider telling Canada that we weren't
really happy with their donation. So the word was that it was going to
be used or else. The "or else" meant loss of program and therefore loss
of jobs.

What was wrong with the arm besides maybe not even being wanted. (There
were station designs that do not require a robotic arm at all.) In one
word it was "fragile". In designs where an arm would be used, it was
used heavily. The entire assembly sequence depended on it. If it
broke, then the entire operation halted. Cargo left in the shuttle would
be left in the shuttle, a major problem for reentry. The choreography
of shuttle manifests and launches would be thrown into chaos. The
estimated mean time between failure (MTBF) of the robotic arm was on the
order of hours. It was a one-of-a-kind design. Every part in it is
proprietary to a few specialty high tech Canadian manufactures with
little product base. The biggest problem was the long tubular arms
which don't contributed to the MTBF but are an immense safety hazard.
All of the station designs have long trusses and look a lot like mad
tinker toy assemblies. The arm was supposed to maneuver loads between
these trusses. If the arm ever came in contact with any piece of the
structure, good bye arm, good bye structure. There were to be no
computational collision avoidance safety systems. The arm was manually
controlled by an operator staring out of a small window with other
astronauts looking out other windows relaying what they saw. Many depth
and visual cues are missing in vacuum because we rely on scattering
effects caused by atmosphere. So controlling the arm was going to be
difficult to say the least.

I took fifteen minutes during the conference to think about alternative
approachs and came up with a robotic manipulator design based on
variable gas pressure in three balloons arranged in an "H" shape as the
motive force. The "H"s were wound in a helix. It would move a lot like
a snake. By comparison with the Canadian arm it would be far cheaper,
easily replaceable, would work with many of the motive components broke,
and could bang against the structure all day long without causing
damage. Robotics is not my specialty so there are probably better ways
than this but the point is that there are alternatives to the Canadian
arm design.

NASA of course spent billions handling or not handling this problem.
Far more than the amount of money Canada put into the arm. It would be
hard to challenge the viewpoint that the space station was designed
around the Canadian robotic arm. Will creating another agency on the
ashes of NASA cause problems like this to not happen? No, there will
always be pressure from where the money comes from to do things for
reasons that will have nothing to do with the task at hand. I spent
some time years later after several other NASA experiences writing
letters to congressmen pleading that they dismantle NASA. I even
received several replies pointing out that while they agreed that NASA
was a mess that it simply wasn't going to happen. It is a jobs program
that affects almost every congressman's district which makes it very
difficult to kill.

Mitchell James
mejames@...
www.InnerTransit.org (Home base for Collaborative Engineering on the web)