DRIVERS NEED NOT APPLY: TerraMax (opposite)
is a self-driving, 7-ton, 6-wheel-drive, all-terrain
vehicle built by Oshkosh Truck Corporation. The
XAV-250 (#15) is a highly modified Ford F-250.
Cornell University’s entry, Skynet (#26), finished
the course in a bit over 6 hours.
Several rounds of tough competition eliminated
most of the contestants prior to the competition’s
final day. Just 11 vehicles out of the 36 semifinalists
were still in the hunt. Those remaining were given
three missions to complete. Moments before race
time, the teams were provided with details of their
secret missions, the information provided as a
computer file on a USB jump drive handed to each
team’s leader. Each mission was different, requiring
the vehicle to negotiate through the sometimes
heavy DARPAtown traffic. To be eligible to win,
a vehicle had to successfully complete all three
missions in less than six hours.
At first look, designing a self-driving car may seem
impossible. But really, “it’s just an extension of present technology,” says Michael Darms, an engineer
with the Tartan Racing team. “Cruise control, which
is a first step, has been around for decades.”
Darms lists numerous examples of existing cars
that handle more and more of the tasks of driving.
Many luxury cars have smart cruise control that
automatically maintains a safe distance from the
cars ahead. Further, some have anticipatory braking
systems that use radar to anticipate a crash and
pre-charge the brakes for a faster stop.
The vehicles at
Urban Challenge must
go beyond simply
removing the driver’s
foot. They must remove
the driver’s brain.
But the vehicles at Urban Challenge must go
beyond simply removing the driver’s foot. They must
remove the driver’s brain. Doing so requires a great
deal of technology. In use here are radar, LIDAR (light
detection and ranging), gyroscopes, and machine
vision sensors, all of which paint an incredibly detailed
digital image of the area surrounding the vehicle
for use by the onboard computer. Control schemes
include sophisticated “fly-by-wire” systems that turn
the car’s wheels and apply its brakes. And the GPS
systems used are incredibly accurate, telling the car
where it’s located to within a few centimeters.
The teams at the Urban Challenge range from
huge groups from corporations and universities with
millions of dollars in funding behind them, to groups
of five or six tinkerers who modified their personal
cars. As one might expect, the greater the resources,
the better the self-driving cars perform, for money
does matter. But all of the robot cars here, even the
low-budget ones, perform admirably. Here are some
typical Urban Challenge entries, ranging from the
simplest to the most elaborate.
SIMPLEST: ODY-ERA
While other entrants have paint jobs proclaiming
Ford, Caterpillar, and Google as sponsors, Ody-Era’s
decals include Papa’s Italian Bistro and Mac’s Fabrication Shop. Ody-Era, a 2008 Mercury Mariner from
Kokomo, Ind., may not be the most sophisticated,
but the fact is, its makers legitimately qualified to
compete at DARPAtown against teams a thousand
times larger and richer. They showed that a few
makers working in a home garage can still attempt
great things.
“We’ve spent less than $20,000 in total on our
vehicle,” says Rick Bletsis, the driving force behind
this self-driving car. Yet Ody-Era made it through
several levels of competition in order to compete
in the Urban Challenge at DARPAtown.
Unlike most other competitors, Ody-Era relies
mostly on machine vision to guide itself through the
course. “We use inexpensive, off-the-shelf digital
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