Machine tool power users have for years used proprietary
communication protocols and custom software to mine valuable process data from
their machine controllers. A better way to collect that data emerged here at
the IMTS 2008 manufacturing technology show.
Called MTConnect, this new open-source communication standard
allows machine tools and related pieces of equipment to pass data from their
controllers to higher level systems. "Think of it as Esperanto for the machine
tool industry," says William Sobel, MTConnect's software architect and visiting
lecturer at the University of California, Berkeley.
vocabulary consists of XML-based descriptions of various machine functions. For
example, it provides the means to describe actual and command positions of a
machine tool's axes of motion. It can do the same with temperatures, power
status and really any other data that a sensor can capture. And it also offers
basic alarm and notification functionality.
Though it was officially introduced just yesterday, MTConnect
already has the backing of big-name machine tool and controls vendors. GE
Fanuc, MAG Industrial Systems, Mazak and other machine tool vendors serve on the MTConnect
Technical Advisory Group that's fleshing out the standard. So does
Bosch-Rexroth Drives and Controls. Here at the show, MTConnect is running demos
in which it will collect data, over the Internet, from machines located
throughout the exhibition halls.
to Sobel, the Technical Advisory Group has worked to come up with standardized
descriptions of machine functions and process data. These descriptions often
make sense for a given type of machine regardless of who makes it. But the
beauty of XML is it offers users the flexibility to create descriptions
that match their particular machine application. "We tried to normalize as much
as possible, but we also wanted to create a broad general spec that cuts across
application areas," Sobel says.
it possible to be both specific and broad. Sobel says users can easily
build their own "domain knowledge" into an XML document without rendering it unreadable
by higher level systems. Some of this customization is already happening as
potential users obtain the free MTConnect source code and start to experiment
with it. Implementations exist not just for machining centers that make the
chips fly but also for metrology equipment, bar feeders, water jet cutters and
points out MTConnect functions as "middlewear" between the machine controller
and higher level applications. Those higher levels could be proprietary data
analysis applications already in use. "We can easily map them to our XML
documents," Sobel says.
MTConnect may also pave the way for applications that analyze process data from
machine tools in new ways. "That's what I'm really excited about," says Scott
Hibbard, vice president of technology for Bosch-Rexroth Electric Drives and
Hibbard says large users of machine tools, such as those in the automotive industry,
have already worked with their machine tool and controls vendors to create
proprietary solutions to their data acquisition problems. "They already have
something that works," he says. But he adds MTConnect's free, open-source
approach opens the door for small companies, university researchers and systems
integrators to come up with new and creative ways to collect and analyze process
data from machine tools.
agrees, and he says MTConnect is playing a role in the development of
new applications that more closely integrate machine tools with CAD/CAM
software. Some of the applications might not even relate to machine tools at
all. MTConnect's approach to defining axes of motion and process data could
just as easily be applied to other industrial machines - including those used
for packaging and electronics assembly. "We haven't focused on other industrial
equipment yet, but our fundamental approach to structuring process data could
be applied to many types of machines," Sobel says.