Although Ethernet makes it possible to use new technologies like cloud computing and smart-phone apps monitor machines from a corporate conference center or hotel room, manufacturing managers are more happy to figure out new ways to empower those who need better connectivity within their facility. When it’s easy to share all sorts of data in near-real-time, operators can improve efficiency without making huge changes or spending much money.
One of the biggest benefits of employing Ethernet on controllers and peripherals like robots is so local people can respond faster when things need to change. When personnel on the plant floor can easily see order requirements and production levels, for example, they can quickly stop runs and make alterations with minimal downtime.
“When product runs are not homogenous, network connection to the database lets the system display HMI [human machine interface] functionality tailored to each model in the mixed product run,” says Henry Loos, controls and application engineer at Applied Robotics Inc. (www.arobotics.com) of Glenville, N.Y. “This makes the operator’s job much easier, and contributes to overall build quality.”
Though making data available to personnel throughout the enterprise was a key driver behind the adoption of Ethernet, communication between devices is at least as important. Machine-to-machine communications across sub networks can bring significant benefits by providing closed loop control.
“Networks allow for instantaneous communications not only between manufacturing devices and the front office, but between the devices as well,” Loos says. “For example, network connectivity allows paint robots to adjust parameters for better quality based on sampling paint only two or three jobs prior. This results in enormous savings and better customer satisfaction.”
Less need for control systems?
Some developers feel that networking can help integrators eliminate some plant floor equipment. When robots and other gear can send data directly to front office systems, the reasoning goes, there’s less need for control systems. That reduces costs and floor space requirements, so it might not be hard to get approval for that type of change.
“When the robot’s controller interconnects with other computer systems on standard Ethernet, they can push information up the line without a PC. The robot can communicate directly to an ERP [enterprise resource planning] system,” says Greg Garmann, software and controls technology leader at Yaskawa America’s Motoman Robotics Division (www.motoman.com), based in Miamisburg, Ohio. “When this data is registered directly into the inventory system, there’s much less data entry.”
It’s not just hardware that can be eliminated. As more powerful microcontrollers make it possible for devices to handle more tasks, system designers are figuring out how to eliminate some layers of software. The services that come with Ethernet let operators communicate with others throughout the entire enterprise with minimal amounts of computing power or bandwidth.
Selam Shimelash, application engineer at Opto 22 (www.opto22.com) says, “Having our controllers speak so many languages natively—including SMTP, which allows them to send emails—helps the customer save space because they do not have to install additional components such as middleware to translate data before it’s passed on to another part of the control system or on up to business apps running on the corporate IT network.”
The data rules
When managers in the front office have access to plant floor data, they can make decisions based on all available data. For example, managers charged with reducing overall costs may want to look at yields and other factors like material costs and kilowatt hours at power consumption.
In contrast, plant floor operators and inventory managers can operate efficiently with only some of that data. When all the available data is held in a central location, it’s much easier for those at all levels to collect and analyze information that’s useful to them.
Converting information into useful formats is one of the many challenges that arise when information streams onto the network from many different types of equipment. “Often, the data that’s coming over the network is obscure and in weird formats. Bringing data up into usable formats is a critical aspect,” says Rick Kuhlman, National Instruments' (www.ni.com) LabVIEW embedded software product manager.
Says Keith McPherson, Rockwell Automation (www.rockwellautomation.com) director of market development for visualization and information software, based in Mayfield Heights, Ohio: “Dozens of different programs have pieces of the total truth. When you’re getting this data directly instead of copying data to a database in the sky, you can get a holistic view that makes sense.”
Terry Costlow, [email protected], is a Contributing Editor for Automation World.
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