Page 345 - Robot Builder's Bonanza

314 BUILD ROBOTS WITH WHEELS AND TRACKS

Idler
wheel
Locking
nut Machine
screw
Idler wheel
hardware
Washer

Idler wheel
assembly

Idlers on
side rail
Figure 26- 20 Construction detail for
the idler wheels. Tighten the locking nut so
the wheel just starts to drag, then back
off the screw 1/8 turn.

3. Using 4- 40 1/2″ screws, washers, and nuts, attach two corner angle brackets as
shown in the illustrations.

Construct the right side rail in the same manner, but in mirror image.

Attaching the DC Gear Motors
Use 4- 40 1/2″ screws and nuts to attach the two motors to the base. The short ends of the
driveshafts should face each other.
Assemble the side rails to the base, using 4- 40 1/2″ screws,
washers, and nuts— see Figure 26- 21. The motors are located at the
rear of the base; the front should be flush with the leading edge of the
right and left side rails.
Temporarily attach the large sprockets to the driveshafts. Using the
hex key included with the motor, slightly loosen the setscrew that
holds the driveshaft in place. As needed, move the driveshaft in the
motor so that the sprocket lines up with the idler wheels in the side
rail. Even a slight misalignment can cause the track to pop off when
the robot turns, so try to be as accurate as possible. When done,
tighten the setscrew on each motor.

Figure 26- 21 Edge view of the idler
wheels attached to the All- Purpose
Tracked Robot Base.

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