Robots: Form or Function?
models shown in Figure 11.
As with almost every
home-built robot, Sojourner is a
work-in-progress. Ken had
previously exhibited another
one of his creations at the SRS
Robothon several years ago
which is shown in Figure 12.
You can follow the steps he
used in designing the
Sojourner robot, see the
CAD models, follow the
various steps in machining the
complex gears, housings, and
structural components, and
see the parts as he fits them
together. I personally spent
hours at his site. Go to
Max’s Little Robot Shop at
FIGURE 14. LOKI's new hand.
FIGURE 15. Willow Garage's PR-2.
Several years ago, I met
Dave Shinsel at a Portland Robotics Society meeting where
he was demonstrating his most unique robot, Loki (as seen
in Figure 13). One thing that immediately struck me when
I first saw the robot was a very capturing personality using
Loki’s swiveling head. This endearing form was
accomplished by well-designed functions. Loki seemed to
me to have that same sort of personal individuality as
Johnny Five did. As Dave says, “Loki” is named after the
Norse god of Mischief since with robotics “anything that
can go wrong, will go wrong ... and usually break
something important.” Loki seemed like an appropriate
keyboard section is covered except during programming.
Dave used two PIR sensors for motion detection, two
ultrasonic ranger modules, four bumper switches, an
electronic compass, and motion encoders on the arms and
wheels. The arms and head motions are driven with Robotis
Dynamixel AX-12 rotary actuators.
I have mentioned Loki before on several occasions,
discussing robot evolution and capabilities. Shinsel has since
added a second arm that is shown in Figure 14. It was
developed so the robot can manipulate things in his
environment. The configuration is entirely different from
the left hand, and makes the robot that much more useful
when it encounters a unique object that requires
manipulation. That is something few anthropomorphic
robot builders ever design into their machines. Dave states:
“The new “hand” is built specifically for opening door
knobs and is a work-in-progress.”
Though Loki is totally autonomous, Dave can also
control the robot via a standard Wii hand controller.
However, it was not the robot’s stunning ability to interact
with people, objects, and its surroundings that impressed
me the most; it was Dave’s use of common materials to
make his home-made robot look like a factory-built product.
I’ve used Loki as an example of a robot’s form, but Dave’s
robot is possibly a better example of an amazingly
functional robot, as well. Dave can be reached at
firstname.lastname@example.org, or Google “Loki” to view some
The Willow Garage PR-2
Dave used a lot of components that many other robot
experimenters have used in their designs, such as a laptop
computer as the main processor, peripheral PIC processors,
and computer web cams for eyes. The robot can use these
simple cameras to track, identify, and guide one of the
manipulators to grasp an object. It is a bit hard to see the
laptop’s configuration in the photograph but the LCD
display is in constant view at the top of the chest, and the
The PR-2 robot shown in Figure 15 from the Silicon
Valley company, Willow Garage, just may be the most
extreme robot designed with both the ultimate in form and
function. When I first heard of the PR-2 and some of the
other Willow Garage projects, I wondered just what WG
was up to. WG was formed by ex-Google employee, Scott
Hassan in Menlo Park, CA, back in 2006, and he tapped
Steve Cousins as the president and CEO.
“Willow Garage is a robotics research lab and
technology incubator devoted to developing hardware and
open source software for personal robotics applications,”
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