CHAPTER 24 ■ BODY BUILDING
Installing the Power Switch
Attach your power switch to the robot’s body.
I really like the shape and feel of the rocker switch. The faceplate on the outside complements the large
nut that steadfastly holds the power switch to the robot’s body (see Figure 24-22).
Figure 24-22. Locking nut being screwed onto rear of power switch
Figure 24-23. Power switch with nut installed on bushing (far left), keyway washer (left), internal-tooth lock
washer (right), and nut (far right)
Installing the Line-Following Switch
Threaded-bushing toggle switches usually come with four circular pieces: two nuts, a keyway washer, and a
lock washer (see Figure 24-23). Sometimes the pieces ship pre-installed on the switch’s bushing (the neck).
Screw one nut onto the switch’s bushing to a point that allows the desired amount of the bushing to
stick out of the robot’s body. Too little bushing doesn’t leave enough room for all the other pieces to be
screwed on. Too much bushing looks gangly.
Then, place the keyway washer (also called a “locking ring”) against the positioning nut. The keyway
washer has a tiny internal tab that fits in a groove (called a “keyway”) on the switch’s bushing. The keyway
washer also has a larger, external tab that presses against the container wall. When securely fastened, the
tabs on the keyway washer prevent the toggle switch from twisting and rotating when the user switches the
actuator back and forth.
On the outside of the container are the lock washer and another nut (see Figure 24-24). The lock washer
helps prevent the nut from loosening and coming undone.