54 SERVO 07.2016
Linear Actuators/Servos
Many times, our designs require that a part simply
extend and retract. This motion can certainly be achieved
by utilizing a servo or motor and adding an additional
linkage to convert the rotational motion to linear motion.
However, if that is the plan, then why not use a product
where that work has already been done for you?
In their simplest form,
linear actuators provide a
forward and reverse motion.
They utilize an internal
motor and worm gear that
converts the motor’s rotary
motion into a linear motion.
This is often preferable to
the circular motion provided
by a motor or servo. Just like
a pneumatic cylinder, they
extend and retract in a
straight line. However, unlike
pneumatics, they do not
require the use of air or any
of the extra equipment. Best
of all, they are much quieter!
The wide variety of
styles and features can make
choosing the right actuator
seem like a daunting task.
We will explore some of the
options available in the hope of demystifying the process,
and allow you to start incorporating them into your
designs.
When drawing up your creations, confirm that the load
rating of whichever model you choose is sufficient for what
you are doing. Also spend some time determining exactly
what stroke length you need as there is a wide selection to
fit your needs. Of course,
cost is also an important
factor, so make sure your
plans fit within your budget!
So Many
Choices
Power Door Lock Actuator
If you want to dip your
toes in the water and try a
simple actuator project, you
might look at power door
lock actuators (see Figure
1). These present a very
inexpensive way to
experiment with the
method, and can help to
visualize how it can be
incorporated into more
complex designs. To keep it
uncomplicated, you can
Up and down, in and out ... how do we make it go? This question can keep me up at
night as I try to devise a solution to get some crazy mechanism I have dreamed up to
work. We have explored many different methods in this series of articles to accomplish
this, and now I have another option for you to consider. We are going to explore how
linear actuators and linear servos can help us become more successful builders.
DIY Animatronics
DIY Animatronics
By Steve Koci
The Ins and Outs of
Making Things Move
Figure 1. Lock actuator and wireless remote.