2008
**Atlanta** (August 25, 2008) --- The Georgia Tech Aerial
Robotics (GTAR) team finished first in the 2008 International Aerial
Robotics Competition at the McKenna Soldier Battle Lab facility in Fort
Benning, Georgia. Georgia Tech's aerial vehicle completed the greatest
portion of the prescribed mission, completing the first, second and part
of the final phase of the mission. This mission must be completed by an
aerial vehicle system with no assistance from human operators during
mission attempts, representing a difficult engineering challenge.
"This competition includes one of the most difficult missions of any
engineering competition," said Eric Johnson, To attempt it, we came with
a system that combined proven components developed over the past six
years with some new components that were put together over the past year
in a challenging system integration effort."
The GTMax-helicopter is based on the Yamaha RMAX helicopter. It was
equipped with two general purpose computers, differential GPS, inertial
navigation and two cameras. The slung-load system consisted of redundant
release mechanisms, a bump-switch to detect hitting a wall to enable
retries, a data-link relay and a magnetometer to measure its twist. The
rover system included a high-resolution camera, a general-purpose
computer to control driving and manage images, and infrared sensors to
enable it to effectively move around rooms indoors.
Software was developed by the team for helicopter navigation and flight
control, three different image processing and tracking systems (locating
correct building based on sign, locating openings and tracking the
opening during approach to the window), automated mission management and
simulation tools.
"We were delighted that all parts of the system were demonstrated
multiple times during our mission attempts," said Johnson. "My worst
fear was that the initial part of the mission would fail and all the
work that went into later phases would be for naught -- like a rover
designed to drive on Mars that fails to get off the launch pad."
The Georgia Tech team made four attempts at the complete mission. On all
four of these attempts, the GTAR research UAV system (referred to as the
GTMax, a small helicopter) automatically flew a three-kilometer flight
to a small village and flew a search pattern, looking at the exterior
walls of the buildings within. It automatically located a pre-specified
sign on one of the buildings, identifying the correct "building of
interest" on all but one of the attempts.
The vehicle then automatically flew a search pattern looking for
openings into the building. Having selected a suitable opening, it then
dropped a 12-foot-long boom on a 90-foot two-wire slung load, allowed to
gently descend by use of a spool/damper system. A camera on the boom was
then used to steer the boom to the opening on the building. The boom
missed the opening in all three attempts, coming within feet of an open
door on one attempt.
The plan was to have a small ground robot drop from the boom inside
the opening. This rover would then drive within the building and take a
picture of a specific item to complete the mission. Due to missing the
openings, the rover was dropped outside the building on these attempts,
and so it drove around outside the building transmitting images relayed
by the "mother ship" helicopter back to the launch point.
"To finish the mission completely in the required time would have been
great, but we are completely happy with the first place finish," said
Johnson. "The mission itself can now retire undefeated, for it will be
something different next year."
This is the final year for this contest mission, one that teams have
attempted since 2001\. Since no team completed the entire mission,
$80,000 in prize money was distributed among the teams according to how
far their system progressed in the mission in 2008\. Having come the
closest, the Georgia Tech team, getting the closest, will receive a
$27,200 prize for its performance.
The competition was sponsored by the Association for Unmanned Vehicle
Systems International. The team consists of graduate and undergraduate
students from Aerospace and Electrical & Computer Engineering. The team
wishes to thank other sponsors of GTAR 2008: Lockheed Martin, Adaptive
Flight Inc., and NovAtel.