Page 238 - LEGO MINDSTORMS - Robotics Invention System-2 Projects

Robot 8 • The ULK (Useful LEGO Knowledge)

Bricks & Chips…

Swivel Casters
The amount of offset provided by the horn has a big effect on the per-
formance of a swivel caster. Casters with a large offset will track better
and result in a more stable robot. Using casters with a small offset will
make a robot’s steering more responsive. If the offset is zero, the caster
will not track, and the robot’s motion is unpredictable.

Caster Step 1 Caster Step 2

Casters have a tendency to steer a robot
as they adjust to a new arming. Anyone
who has pushed around a heavy
shopping cart is familiar with this
phenomenon. ULK uses a hard plastic
wheel in its caster to minimize traction
and reduce caster steer.

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