Notes:
Neither are polarized, so if ground and power are reversed, an AC motor will turn the other way, while a DC (Stepper) Motor will jerk about.
Sometimes the Voltage is enough, but Amperage is not.
The Nano output pins only output 3V and 30 milliamps, which is not enough to
The theme: things in the real world are big. So far we’ve only been working with small LEDs, but moving larger objects like industrial fans or humans or making wind
How do we do this? With a Power Switch Tail.
This connects to the arduino’s ground and signal. The arduino can then be used to control a lever, an air conditioner, a large light, etc. It can only turn on and off fairly slowly however, and can’t dim. You can build one on your own, but AC electricity is dangerous.
Geared DC Motors are pretty easy to work with -- you can just supply the power and they turn at the RPM they are specified. Just find the RPM you need and make sure you can supply the power it needs.
One downfall of AC and DC Motors are that unlike servo motors, we can’t get the kind of feedback that tells us where the motor is, and they just turn and turn. One way to circumnavigate this is to work with DC Motors with encoders, which can tell you where your motor is.
We’ve only worked with servos so far.
A good replacement for servos is this stepper motor. Harder to work with because it has more pins.
However, servos can be more reliable because they will always go to where you tell them to go - even if it gets stuck, or even if you try to move it out of its position, it will return to it. It’s limitations are that it is slow, and it only has a 180 degree range of motor. Circumnavigate the latter with a continuous servo.
Auto gauge servos are a good option for moving very small things and easy to work with because they can connect directly to arduino pins.
Good practices:
- Buy a power supply with higher Amperage than what you need because sometimes motors use more than what the spec sheet says. (This is not dangerous. Voltage can be.)
Having a motor is only half the work. The other half of the equation are mechanical linkages.
In some projects this is the bulk of the work, more so than programming.
All of these (and the above) are here.