Meet: Tim Gallagher
Mars Pathfinder, Camera Control Electronics Designer
Lockheed Martin, Colorado
My Involvement With Mars
About three to four years ago while working on an instrument package
going to Saturn's moon Titan, I was asked to join the Mars Pathfinder
team because of my previous experience with imaging electronics. This
was to be a fast-paced design proving NASA's quicker, simpler and cheaper
philosophy for the next generation of small spacecraft systems.
The Imager For Mars Pathfinder (IMP) design, as quoted from the Mars
Pathfinder forum at http://mpfwww.jpl.nasa.gov/mpf/sci_desc.html#IMP "...is
a stereo imaging system with color capability provided by a set of selectable
filters for each of the two camera channels." Please refer to the Web
page above for a more detailed description of the science packages. Note
that there are two main parts of the Pathfinder: the instruments or payload
such as the IMP and rover Sojourner, and the spacecraft that delivers
the payload to Mars. The design, launch and control of a spacecraft is
very different from the development of an instrument package. The IMP
system is basically along for the ride and hopefully after a successful
journey and landing on Mars, it will start sending back pictures.
Our design interfaces included a Charge Coupled Device (CCD) and an
IBM computer system used to control the taking of pictures (images). A
CCD converts light (photons) to an electrical signal, which after processing,
forms a picture. Basically, we built the electronic modules in-between.
After studying the CCD and IBM interfaces we started the design in earnest.
To save space and cost it was decided to use Very Large Scale Integration
(VLSI) circuits such as a Memory Multi-Chip Module (MCM) and a field-programmable
Gate Array (FPGA). The Memory MCM could hold multiple pictures allowing
the IBM computer to read out the images at its leisure while performing
other critical tasks. The Gate Array was engineered to contain many smaller
control circuits inside which saved space, weight and costs.
After designing the system we built a prototype or working model and
started integration testing. It is necessary to test new hardware and
software together to work out all the bugs (things that don't quite work
right). The IMP interface software was developed by University of Arizona
engineers. The software controlled the sequence necessary for imaging
and the movement of the camera motors and filters.
We had a lot of fun designing and testing the camera system. It was
really interesting taking pictures in the lab for the first time knowing
that in the near future it will be on Mars returning snapshots of that
Now my involvement with Mars is just like yours - I am anxiously awaiting
the July 4th (or 5th) landing of the Pathfinder this year and the first
pictures sent back. Just before the Pathfinder arrives at Mars I will
become more nervous (as nearly everyone involved will, especially those
at NASA and the Jet Propulsion Laboratory) because our time is at hand.
As a side note to planetary exploration, l have a story about a good
friend named Larry Padgett. Larry has worked on an instrument package
going to Saturn's moon Titan for the past six years. The launch date of
this vehicle is set for later this year (see DISR section below). The
spacecraft will take about eight years to get to Saturn before it can
start sending information back to Earth. By that time Larry will have
spent 15 years of his life waiting to see if his designs worked! This
is what planetary science is all about!
My Career Journey
I've had several previous engineering jobs at Lockheed Martin.
Zenith Star: Part of the so-called "Star Wars" effort to design a very
large space-based laser system with accuracy abilities equivalent to lighting
up a basketball on the top of the Empire State Building from Denver, Colorado!
The final laser would have been as large as a Greyhound bus and in space
it would have been visible as a small speck on a clear night to the unaided
eye. My job entailed integrating many Reduced Instruction Set (RISC) processors
and development of the math library.
Flight Telerobotic Servicer: The robotic arm that was planned to help
build the Space Station and relieve the astronauts of many dangerous tasks.
It was very interesting to learn the control algorithms necessary to move
an object in three-dimensional space. My job was to integrate the hardware
and software systems.
Brilliant Pebbles: Another "Star Wars" idea that relied on many small
"pebbles" (file-cabinet-sized satellites) to release a kinetic kill vehicle
toward a hostile missile target. The kill vehicle would destroy missiles
by impacting them, equivalent to firing a bullet to hit another bullet.
My job was to design the first prototype of the controller system between
the booster and the kill vehicle.
Descent Imager/Spectral Radiometer (DISR): An instrument package for
the Cassini mission heading toward Saturn. The DISR is part of the Huygens
Probe, which will descend into the atmosphere of Saturn's moon Titan and
make imaging and spectral observations. My job was to design and develop
both the CCD and infrared imaging simulators and the payload interfaces.
Cassini is scheduled to launch later this year.
Imager For Mars Pathfinder: As described at the beginning of this page.
Multi-Service Launch System (MSLS): To quote Lockheed Martin, "The Multi-Service
Launch Systems Program provides an effective and efficient launch service
for a variety of different payloads, at great savings to the American
taxpayer." Basically, it converts Minuteman II missiles from a wartime
mission to a peacetime one instead of destroying them. My job was to design
the software to control the missile's booster, nozzles and payload interface.
MSLS had its first launch last year, which was very successful.
Data Link Formatter: A very high-speed state-of-the-art data handler
system. Taking in up to 4.8 Gbps (billion bits per second), it can queue
(keep track of), format, control and route data to an output system as
needed. Attached to this is a 500 Gbit memory system (imagine having 4000
times more memory for your home computer!). My job was to architect the
system and support the program in an advisory position.
My Current Job
I'm now working on the Evolved Expendable Launch Vehicle. This is a
study program to develop a new family of cost-effective, highly responsive
launch vehicles. We are involved in a competitive run-off for America's
next generation of space launchers. The challenge for this program is
to rapid-prototype and demonstrate system designs along with keeping costs
to a minimum without sacrificing safety or system capability. My job is
to lead the power controller hardware and software design.
For further information about Lockheed Martin products and services
please refer to http://www.lmco.com/closer.html or for contact information
such as employment opportunities go to http://www.lmco.com/contact/
For further information about Lockheed Martin Astronautics, Denver,
CO go to http://harpo.ast.lmco.com/
How I Became an Engineer
In high school I wanted to be a veterinarian and even worked occasionally
at an animal hospital next door to our house. However, by the time college
arrived I didn't know what to do. Because of a low draft number (less
than 100) on my 18th birthday in 1969, and the escalation in Vietnam,
I joined the Air Force (my father had been in the Air Force during World
War II). After a tour in Vietnam in the early 70s (working in a field
hospital which was just like the TV show "M*A*S*H"), I wisely transferred
to the Electronic Computer Repair field. The military provided excellent
technical schooling both in electronics and computers and gave comprehensive
on-the-job training. After spending some very productive and entertaining
years in the Air Force, I joined Westinghouse (Baltimore) to finish my
Electrical Engineering degree at University of Maryland (College Park).
Over 11 years ago my family and I decided that Denver, Colorado was a
great place to live. At that time Lockheed Martin (formally Martin Marietta)
was hiring a lot of engineers and it didn't take long for me to get an
offer and then accept it. Since then I have stayed put and finished a
Masters in Engineering from University of Colorado (Boulder).
It was pure chance that I became an engineer. After Vietnam I really
wanted out of the medical field and one of the few openings in the Air
Force at that time was for Electronic Computer Repair. While attending
electronics classes in my new field I discovered that I had an aptitude
for it and thus my career started. Before the Air Force classes the only
electrical thing I knew was how to screw in a light bulb!
I am married to Van (pronounced Young) and we have a teenage daughter
named Kim. Kim would really be mad if I didn't mention her name a few
times in my bio - so Kim, Kim, Kim, Kim, and Kim!
Kim, 16 years old, currently attends Heritage High School in Littleton,
Colorado. She enjoys playing competitive softball in the summer (her second
year at it) and for the school as well. We enjoy watching Kim play and
during the summer our vacation is going to softball tournaments.
We have a pet cockatiel named Christina who is very smart and can be
quite a troublemaker.