Exclusive interviews with technology leaders
Economical motion control: low dollars
and good sense
Brad Slye, President, Drive Control
Systems, Minnetonka, MN
Mr. Slye has been president of Drive Control Systems
(DCS) since January 1997. Employed by the company since
1987, Mr. Slye first worked as a design engineer and
in 1990 became engineering manager. He received his
BSEE from the University of Minnesota in 1983, following
which he was employed as an electrical engineer before
Interest in the class of single-axis motion controllers
for continuous motion is growing, thanks to the technology's
ease-of-use and quick payback.
Design News: How do you define economical
Slye: To me, economical motion control is a
system that meets the user's needs and pays for itself
in a short amount of time. So the fact that one of our
units costs $900, for example, does not make it economical
in and of itself. The improvement in production processes
that it delivers also helps to achieve a quick return-on-investment.
The factors that contribute to a short payback period
can be very subtle. For example, we have special units
for wire machine operators that allow them to enter
their setpoints and variables in units that make sense
to them. In this way, they can directly set and very
precisely maintain something like slip percentage to
a significantly lower value, which they could not do
in the past for fear of snapping the wire.
Q: How has demand changed for economical motion
A: Since the mid-1980s when the company was
started, we've seen unit volume grow every year. I think
one of the reasons engineers are moving to this technology
is that they want to be producing good products right
from the beginning of the process. Without motor control,
operators will be tweaking things back and forth for
the first 10% of the run. Likewise, they have to scrap
the product produced at the end of the run when the
machine is slowing down to a stop. Another reason is
that factories everywhere used to have a staff of production
engineers, electricians, or somebody who really understood
how the production machines and processes worked and
knew how to fix problems. But a lot of those people
retired or were laid off and never rehired. Since many
factories today cannot depend on knowledgeable people
to oversee these processes, they work with com- panies
like ours that can help them control the process. And,
finally, as ac and dc drives become smarter, the line
between our controllers and other more expensive offerings
on the market is blurring. We're competing against servo
in a wider variety of applications.
Q: What is the biggest challenge associated with
marketing an economical controller, when the servo mindset
is frequently that the most expensive solution is the
A: I think there is initial skepticism on the
part of some potential users-they aren't sure that they
can get the performance they need out of a controller
that is a fifth the cost of other controllers. So the
hardest challenge is simply getting them to try it out.
The way we've overcome that hurdle, though, is by being
successful in the marketplace and by solving more and
more applications out there. It's much easier when you
can tell a customer that he isn't the first one to apply
a technology in a particular way.
Q: What do design engineers need to know in order
to make the best choice in motion control for their
A: They need to know what size motors they plan
to use and how many axes they need to be control, and
whether the motion required is continuous or point-to-point.
They need to know what kind of investment they are prepared
to make-if any-in programming and learning to use a
new system. They also need to ask themselves how much
operator interaction they want and how the machine is
going to be maintained.
Q: Can you give us a preview of some of the technology
developments in the works?
A: To give you kind of a historical perspective,
our product has gotten more diverse over the years.
On our new MS 232, we will be having panel-mountable
units with multiple axes built right in. We will also
have applications built directly into our controls.
In fact, we've already done control for weaving machine,
tension control, traverses, winding and unwinding, electronic
gear boxes, index registration, and other applications.
Controllers of the future will be even easier to use
and customers will be able to order a particular controller
by function, which more closely matches the thought
process when specifying a controller.