Turn-Offs: Human drivers
Adam Solomon, Lockheed Martin engineer and race
track barrier strength-tester, gave me the scoop on their Prius.
The first thing that jumps out and slapped me in the
face is the fact that this car looks so normal I couldn’t help
myself: “This car looks kinda boring. But that’s a backhanded
compliment! Honest!” Just as Toyota set to achieve (and
did so) utter normality with the Prius to not freak out
potential customers who fear change and abnormality in
their daily drivers, so did the Ben Franklin team also achieve
remarkable normality with their robot car.
This was the backup car (“backup” not as in “it goes in
reverse,” but “backup” as in “if we total Little Ben, we’ve
got a spare!”) for Little Ben at the DARPA Urban Challenge.
Little Ben ran so well that this vehicle wasn’t needed for
that event. In its understudy role, as on Broadway, it wasn’t
equipped as well as the top-billed star was in order to
put on a standing ovation, throw-the-roses-on-the-stage
performance. This car had only two main sensors vs. Little
Ben’s 11. This bears repeating. According to Adam, with
only 18% of the hardware bolted to the outside of this car,
it could perform at 95% of the capacity of Little Ben. The
5% shortcoming is in this robot car’s inability to perform
sensing of extremely close objects — the Prius’ roof eclipses
the field-of-view of the one centrally-mounted roof sensor,
casting the area immediately around the car into “shadow.”
How is this possible? Software, software, software.
They refined their software over and over, making it more
efficient, more robust, and more powerful, until they had
this impressive driving capability-per-sensor ratio (Don’t ask
me what the units are on that value ...). Did I also mention
that the star of their robot — the software — runs on a plain
old consumer MacBook Pro laptop? Their biggest problem
with their whole system was not any of their components
or code but the laptop’s rechargeable battery, which
gradually lost its capacity over the months of testing from
its frequent charge and discharge cycles. They learned their
lesson and now keep the laptop plugged in at all times.
Lockheed Martin is also continuing to use this Prius as an
active research vehicle, constantly refining their software.
Why? They have plans to transition their refined software to
other vehicles, including boats and military tactical vehicles.
Could they end up developing a ubiquitous “operating
system” for robot cars? Perhaps standardized tests of the
future will include the following analogy: Microsoft is to
consumer PCs as Lockheed Martin is to robot cars.
Like Boss, Little Ben’s sensor-challenged brother starts
with a map of the course and then uses those sensors to
determine exactly when to turn, how sharply to turn, and
how to deal with obstacles that can’t be pre-programmed.
Adam’s analogy was your GPS unit in your car. It tells you
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