Though the lines can often be blurred, robotics and motion control are not the same thing. They are closely related in many ways, but robots lean towards more “pre-engineered” solutions while
motion control leans more towards modular solutions.
This small but signifcant distinction poses a number
of aspects for decision makers to consider when choosing the
solution that is best
for their process. Think
about your answers to
the following 10 questions and use them as indicators for your decision.
These questions are the building blocks for choosing
between robotics and motion control. Use them when designing for your project and keep in mind that the answers
are all relative and dependent upon your application.
1. DOES A BOX-LIKE OR CYLINDER-LIKE SHAPE FIT
YOUR WORK AREA/APPLICATION BETTER?
Robots tend to be centered around a base, giving them
a cylindrical or ball-like work envelope. Cartesian “robots”
that break this mold do exist but they are in the minority.
While general-purpose motion controllers can be used
for robots, they lean more towards modular and linear
mechanics that result in XYZ box-like work envelopes,
with the rotary axes being moved instead of stationary.
2. DOES THE SOLUTION NEED TO SATISFY
MULTIPLE PROJECTS WITH HIGHLY DIFFERENT
Robots come in many shapes, sizes, and form factors.
The controls can be signifcantly different from project
to project. Modular mechanics are great for mixing and
matching axes to optimize performance for the given
requirements, because motion controllers are well-suited
for controlling many different types of axes.
3. WILL YOU REPURPOSE AND REUSE
If your design happens to be a short-term project or a
prototype, then having the fexibility of interchangeable,
modular mechanics that can be swapped in and out can
be a huge beneft. Singular pieces of motion control
elements are easier to transfer among projects than
fully-assembled robotic elements.
4. DO THE MECHANICS NEED TO FIT IN
A SPECIFIC GEOMETRY?
With a project that is confned to specifc dimensions,
modular mechanics are more fexible to different combinations and customization. Robot types like Cartesian,
six-axis and selective-compliance-articulated robot arms
(SCARAs) are better suited for projects that have a more
generic size and space to work within.
5. DO YOU HAVE HIGHLY DIFFERENT
REQUIREMENTS FOR THE DIFFERENT
DIRECTIONS OF MOTION?
Sometimes the needs of the various axes of motion in a project are vastly different. For example, in an
XYZ system, X may
require fast and
inaccurate motions, Y may require slow and highly
accurate motions, and Z may not have
requirements for either but focus on force
alone. Modular solutions can come with con-fgurable and adaptable components to ft
6. DO YOU HAVE A SPECIFIC TYPE OF
PROGRAMMING LANGUAGE, FORM-FACTOR
OR ARCHITECTURE THAT YOU WANT TO EMPLOY?
General-purpose motion controllers come with a dizzying
array of capabilities, giving an almost unlimited selection
of languages, form-factors and architectures to choose
from. The design of robot controllers tend to be more
focused on the purpose of the robots they are paired
with, simplifying the process of choosing one.
7. HOW MANY AXES OF MOTION ARE REQUIRED
FOR YOUR APPLICATION?
It is common to see robots with six degrees of freedom
that allow them a wide range of motion. If you have an
application that will require the use of those six degrees
of freedom, robotic control is probably the better option.
Designing a system of modular mechanics to use the
same DoF as the robot is possible, but can be a challenge.
8. WILL YOU EVER WANT TO ADD ON MORE AXES
TO INCREASE FUNCTIONALITY?
Once you’ve implemented the robot, will you ever want
to add on an extra axis or two? Robots are pre-engineered
systems that do not offer much fexibility for adding on
more axes later. Modular motion control, on the other hand,
make that much easier to do. For example, an engineer
could purchase an 8-axis controller and just two axes
of mechanics. Later on, more axes could be added and
later still, additional axes could be implemented again.
9. ARE ANY OTHER HIGHER-LEVEL FUNCTIONS
REQUIRED BEYOND THE MOTION?
The implementation of other important factors such as
machine control, remote I/O and data collection should
all be taken into consideration when designing for your
process. Many motion controllers have the ability to become “machine” controllers, which means they have the
capabilities and processing power to handle more than
just the motion control at the heart of the application.
10. WHAT ARE THE ENVIRONMENTAL CONCERNS?
Robots are easier to protect in extreme environments.
Some even come predesigned for specifc requirements,
like IP69K. While not impossible with modular mechanics,
there are numerous hurdles to overcome if they will be
exposed to harsh environments.
Corey Foster is an Application Engineering Manager at
Valin Corporation, a leading technical solutions provider
for the technology, energy, life sciences, natural resources,
and transportation industries.
For more go to: newequipment.com/robots-or-MC
Robotics or Motion Control? 10 Questions to Help You Decide
Before deciding to install a robot or go with motion control components for your application, here are ten questions to ask yourself.
by Corey Foster