they simply need to be plugged into a wall outlet
The actual motors without the nice external case
can also be purchased on eBay (Figure 5). If you are
able to utilize them in this manner, it does allow you
to take advantage of a wide selection of rotational
speeds. It can be a little extra work to install them in
your design, but may be just what the doctor
ordered to get the exact motion you desire.
ServoCity has a full line that will fit most any
build requirement and is a good place to start your
search (see Resources). Among those they offer are
models that come equipped with an encoder for
feedback. A variety of price points and RPM ranges
are available. If you use the Actobotics products,
they include a variety of mounting options that
allow you to easily incorporate these motors into
your projects. Gear motor power boards are also
available, making the electrical connections a
There are models that come in a right angle
configuration that can come in handy in some
These motors provide the propulsion for my
Robospider and for Jarvis (Figure 6). You can check those
builds out in the September 2015 and September 2016
issues of SERVO Magazine.
All those old but still functional power tools that have
been gathering dust under your workbench can find life
again. They can be re-purposed into effective prop motors.
I have seen Sawzalls, palm sanders, jigsaws, and
powered screwdrivers all used very effectively in props, so
you are only limited by your imagination.
You can oftentimes find old but still functioning corded
power tools at the thrift store as the popularity of battery
operated models increases. In fact, I would wager that
most of us have at least one of these buried somewhere on
our workbenches. It is time to blow the dust off and put it
back to work!
Windshield wipers are not the only automotive motors
that can be included into our designs.
One of our old time favorites was the automotive vent
motor (Figure 7). Vent motors (or more properly known as
blend door actuators) can still be found. Although the days
of picking these up from the surplus sites at $5 seems to be
over, they can still be found for around $20. If anyone
knows of a source that still stocks the inexpensive models,
please share with the rest of us.
Other useful options include window and adjustable
seat motors. All of these can often be picked up at a scrap
yard for a reasonable price, although you usually must
supply the tools and elbow grease to remove them from
These are a brushless DC motor that divide the full
rotation of 360 degrees and break it down into equal steps
Stepper motors are great when you need very fine
control, as you can precisely control both the position and
SERVO 04.2017 17
Figure 6. Lots of Actobotics motors from ServoCity to choose from.
Figure 7. Vent motors fill a wide variety of needs.
Figure 5. Using the bare reindeer motors gives you