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meant to be accessible robot kits that would be ideally
suited to kids and students just starting out in their robotics
endeavors. We think pliers are recommended because they
are the type of tool that pretty much everyone will have
lying around. Socket wrenches are a little more specialized,
and not everyone might have a set of them on hand. In any
event, pliers will definitely get the job done.
Much of the construction on the Bogie is dedicated to
the cool rocker-bogie suspension from which the robot
takes its name. The rocker-bogie design has quite the
design pedigree — it’s the preferred suspension setup of the
Mars rovers including Spirit, Opportunity, and Curiosity. The
rocker half of the name refers to the linkages that abide by
the definition of “rocker” with respect to four bar linkages.
A rocker linkage is one that has a limited rotational
range. The bogie aspect of the name refers to the driven
wheels at the end of each linkage. For the Mars rovers, the
rocker-bogie suspension is designed to allow the bot to
tackle obstacles while keeping all six wheels on the ground,
and minimizing the tilt of the main body. We love that the
inclusion of the suspension design is as instructive as Navi is
for Link — it’s a great example of good mechanical design
that provides a springboard for discussion of some of the
coolest, most out of this world robots of recent memory.
We couldn’t think of a better way to get novice roboticists
excited about the possibilities of science and engineering.
As with any truly elegant design, the rocker-bogie
suspension comes together pretty easily. The linkages are
connected with a few screws, and the differential between
the two sides simply uses a few L-shaped brackets. The
decent size of the Bogie also ensures that you’re never
scratching your head about how to get your screwdriver
into a snug spot to tighten that last stubborn screw that
seems to be as intent on hiding as Don Quixote is at tilting
at windmills (despite Sancho Panza’s puzzlement).
Even without wiring up the Bogie, it’s fun to test out
by pushing it over uneven terrain and seeing the rockers
undulate. Though, of course, it would be even more fun to
see it do that under its own power.
WIRING UP THE BOGIE MOTORS.
THE ROCKER-BOGIE SUSPENSION.
Lauren Lewis from RobotZone