Make: Robotic Arms

9Chapter 1: The Foundation of Robotic Arms

analog sensors. One of the best ways to start learning about reading analog

signals is to wire up a potentiometer and use one of the analog input pins to

measure the position of its knob. In fact, in just a few pages, we’ll be building

a circuit that can pull this off.

Potentiometers, like the one pictured at right [Figure

1-10

), are small

knobs that typically have three electrical connectors. (These are also, as

we discussed earlier in this chapter, the small devices inside servos that

help the motor keep track of its position.) Potentiometers rely on a concept

known as electrical resistance. When the ...