Make: Robotic Arms

37Chapter2: Two Degrees of Freedom

create a truly random number. Creating a near-

random number, however, is much easier. When

the Arduino begins its algorithm for generating a

pseudorandom number, there is always a number

that serves as an input to the algorithm. The

randomSeed() command defines that starting

input number. In our case, we are using the

voltage from analog pin A0. Because we don’t

have a device such as a potentiometer plugged in,

nothing is connected, and that pin is considered

to be floating. A floating pin will often have wildly

fluctuating values, which serve as the input for

our random number algorithm, meaning our

numbers ...