10 March 2011
Electronics: cause and affect
Today we'll look at output devices that are a bit groovier than LEDs.
To get started we'll need to finally cover some of the details of:
- voltage, measured in Volts (V)
- current, measured in Amps (I)
- resistance, measured in Ohms (Ω or R)
- Ohm's law: V = IR; I = V/R; R = V/I
BUT! There's a lot more to learn! We're just going to cover the bare essentials. This stuff is really
fun and gets more and more interesting the more you learn, so I encourage you to do some additional
reading on Ohm's law, voltage, current and resistance, etc.
Then we'll move on to using small Arduino signals to control large loads:
- the basic
TIP120 transistor driver circuit: used to control a large voltage/current with a small signal
- simple DC motors: fast, cheap, out of control
- DC gearhead motors: slower, expensiver, controllerer
- hobby servo motors: annoying noises, semi-precise positions
- stepper motors: can be super precise, need extra code + circuitry to control
- solenoids: small linear movements, banging on things
- relays: switch a switch with a switch
There's a good chance we won't have time to get into all of the different motor types.
Check out Motor Mania! and
Electronics Workshop for Artists
for lots of additional info.
Tom Igoe @ NYU's ITP program has lots of great info on his
website.
The ITP
Physical Computing site is also a good resource.