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Input: DC or AC Power.
Output: Mechanical energy in the form of rotational movement.

Motor Properties

• Motors convert electrical energy into rotational movement.
• Linear motors also exist. They provide straight line movement. Wikipedia

Conventional Motors have a Two Wire Power Connection

Normal motors run at a speed determined by the power supply voltage and the load on the motor.
This is fine for devices like cooling fans or motors used to drive vehicles.

• They spin in a fairly uncontrolled way.
• They are useful for propelling vehicles, powering fans or spinning the washing.
• It is possible to measure how fast the motor is spinning but the exact position of the motor is not generally known.
• These motors can be any size including huge motors for driving ships or trains.
• It's easy to make a big powerful motor
• It's easy to make a motor that runs at high speeds
• Simple switches or electronics are used for power control
• They are efficient - most of the electrical energy is converted into mechanical form
• QE2 Engine Room - Big Motors 9 metres across.

Motor Drivers

• MOSFET switches are commonly used.
• The Back EMF Diode is important.
       It protects the MOSFET from high voltages.
       It prevents sudden current changes in the motor which would cause the damaging back EMF voltages..