The motor is activated using electromagnetic coils, which magnetise cogs on the gear wheel. To move the cog, the coil currently holding it is turned off and a different one is turned on. The magnetic pull the stepper-motor exerts on the cog teeth thus causes the wheel to change position. One such change is referred to as a “step”.

1. Practical Applications of Stepper-
Motor in Hobby Electronics
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2. Practical Applications of Stepper-
Motor in Hobby Electronics
What is a Stepper-motor
Simply speaking, a stepper-motor is a brushless motor running on a DC
current, which is able to split one full rotation of a gear cog into a number of
equal steps. These steps do not have to be sequential (i.e. in the same
direction, rather than moving first forward and then backward) – though in the
simplest configuration of the motor they often are.
http://proto-pic.co.uk

3. Practical Applications of Stepper-
Motor in Hobby Electronics
How It Works
The motor is activated using electromagnetic coils, which magnetise cogs
on the gear wheel. To move the cog, the coil currently holding it is turned off
and a different one is turned on. The magnetic pull the stepper-motor exerts
on the cog teeth thus causes the wheel to change position. One such change
is referred to as a “step”.
http://proto-pic.co.uk

4. Practical Applications of Stepper-
Motor in Hobby Electronics
The motor is used to make adjustments in positioning devices, for example in
the laser head in a DVD or CD player. The clicking sound you sometimes
hear in older DVD and CD players is an old stepper-motor losing its grip.
http://proto-pic.co.uk

5. Practical Applications of Stepper-
Motor in Hobby Electronics
Pros and Cons of using Stepper-motor
The motor suffers from a lack of torque at higher speeds. The faster the
wheel turns, the more the cog is likely to slip. So applications requiring the
motor to turn at high speeds may be better served using a servo motor
instead. The resonating effect also exhibited by the stepper-motor at high
speeds may have an adverse effect on device performance.
http://proto-pic.co.uk

6. Practical Applications of Stepper-
Motor in Hobby Electronics
The plus points of the stepper-motor are many. For example, its relatively
low cost and high reliability at low speeds make it ideal for a wide range of
amateur projects. While its simplicity of design means it can operate in even
quite difficult conditions, where a more delicately calibrated motor may have
trouble functioning properly.
http://proto-pic.co.uk

7. Practical Applications of Stepper-
Motor in Hobby Electronics
The motor does suffer from limitations of size, in that it gets too big
where a large degree of steps are required (and hence a large number of cog
teeth).
http://proto-pic.co.uk