Some of our favorite hobbyist electronics utilize motors to mobilize, making them fun and awesome! Including a motor in your project could be challenging, especially if you have never worked with them before.
The following Instructable will explain how motors work, and break down some of the most commonly used kinds of motors.
Step 1: The Fundamentals
Magnetic fields produce physical force that can move things. Every magnet has a magnetic field with a north pole and a south pole. If you try to push the north poles of two magnets together, they will repel each other. The same thing happens if you try to push two south poles together. If two poles are the same, they will repel each other. If, however, you play with two magnets and bring the north pole of one close to the south pole of another, they will attract each other and stick strongly together, opposite magnetic poles attract each-other.
An electric motor uses the attraction and repelling properties of magnets to create motion. There are two magnets in a standard electric motor: a permanent magnet, and a temporary magnet. The temporary magnet is a special kind of magnet, called an electromagnet. An electromagnet is created by passing an electric current through a wire. The permanent magnet has a magnetic field (a north pole and a south pole) all the time, but the electromagnet only has a magnetic field when there is a current flowing through the wire. The strength of the wire's electromagnetic magnetic field can be intensified by increasing the current through the wire, or by forming the wire into multiple loops.
In an electric motor, the electromagnet is placed on an axle so it can spin freely inside the magnetic field of a permanent magnet. When an electric current is passed through the wire, the resulting temporary electromagnetic field interacts with the static permanent magnet, and attractive and repelling forces are created. This excitation of the wire, or electromagnet, propel it to spin on its axle, and an electric motor is born.
Motors are classified by having the following properties:
- There's a permanent magnet (or magnets) around the edge of the motor case that remains static, so it's called the stator of a motor.
- Inside the stator, there is a wire coil, mounted on an axle that spinsaround at high speed - this is called the rotor.