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wheels to lose their grip on the ball. Dropping the
robot or other similar trauma during transport
or use can also cause this. One sign that the
space among the wheels needs to be adjusted is
that the machine releases the balls at irregular
lengths at high speed. When the length of the ball
throws becomes irregular, the space among the 3
wheels needs to be adjusted.
To check the space among the wheels, place the
Wheel Adjustment Gauge (black tube with 3 fins)
in the space among the 3 wheels, fins end first,
and so the fins do not touch any wheel (see Photo
8A). Now move it in and out. If the distance is
correct, the gauge can be moved in and out easily
and with the wheels just barely touching the out-
er surface of the gauge (wheels may turn slightly
as the gauge is moved). If the wheels do not grip
the gauge at all, or conversely, they tightly grip
the gauge, then wheel adjustment is called for.
To adjust the wheels, push the gauge into the
end of the Ball Tube where the ball comes out so
it is held rigidly in place. Then use the 4 mm hex
wrench found in the accessories to loosen the
hex screw near the cover of the motor (see Photo
8B). Now move the motor (gripping its cover)
either towards or away from the gauge until the
wheel barely touches it (see Photo 8C). Lastly,
tighten the 4 mm hex screw to hold the wheel in
place. Do this with all 3 motors.
Please note: The diameter of the adjusting tube is
35 mm, which is the ideal amount of space among
the 3 wheels. The robot functions correctly up to
a diameter of 37-38 mm.
Replacing The Wheels
When the wheels can’t be adjusted anymore, or the special coating on the wheels has worn off, the wheels
should be replaced. To do so, start with the lower wheel. Using the smaller 2 mm hex wrench, loosen the
small setscrew that holds the wheel onto the shaft of the motor (see Photo 9A) Before taking it off, check
and memorize the exact position of the wheel on the shaft of the motor. Pull the wheel off the motor
shaft and remove the three #1 Phillips screws that hold the foam wheel onto the hard plastic hub. Remove
the wheel from the hub and replace with a new wheel. Then refasten the hub to the wheel. Slip the wheel
assembly onto the motor shaft until the position of the original wheel is reached.. Tighten the setscrew.
Now manually spin the wheel to be sure it is not rubbing on any surface. If so, loosen the setscrew
and slightly move the wheel’s position on the shaft and try again until the wheel no longer rubs on any
surface. Lastly, tighten the setscrew securely.
Photo 8A
Photo 8B
Photo 8C
