How Embedded Systems Are Changing Automation

Over the past decade, new microprocessor technologies have literally changed the face of business and consumer computing. Your tried-and-true automation technologies are now going through a similarly dramatic change.

A shot of the production floor at Haeusler where embedded technology has altered the company’s machine control concept.
A shot of the production floor at Haeusler where embedded technology has altered the company’s machine control concept.

Desktop computers once ruled the computing universe in the distant past that most of us refer to as the early 1990s. But by the turn of the millennium, less than 10 years into their rule, desktops had largely given way to laptops. And in the past few years, we’ve begun to see the erosion of laptops’ dominance as the computing platform of choice, since we all do more with our cell phones and tablet PCs.

All of this change has been the result of two things: a desire to make computing easier and more portable; and the ability of integrated circuits to deliver massive amounts of computing power in increasingly smaller packages.

Since automation devices typically leverage the same technologies as the consumer sector—though in more robust packaging—what does all this change mean for automation? That answer has yet to be fully determined, but inroads are already being made to alter automation technology. Though the form of automation may not change as dramatically as we are seeing with the desktop to smartphone/tablet transition, its function certainly will.

Here’s why.

The Transformation Is Already Underway
Let’s start by making it clear that these new microprocessor advances in automation will not start impacting industry at some point in the future. The impacts are already being felt in some of the most core manufacturing sectors such as pipe manufacturing and die-casting.

>> Understanding Embedded: To navigate the embedded world, a few key terms must be understood. Click here

Machine manufacturer Haeusler, headquartered in Dornach, Switzerland, has been in business for nearly 80 years and now manufactures 20 different types of plate and section bending machines. The company’s machines are used in shipbuilding, the automotive and aerospace industries, container construction, the manufacture of pipes for pipelines and wind farms, the manufacture of heat exchangers in heating systems, and in steel construction.

Because control of the forming process is one of the main quality features of its machines, the company decided not just to update its machine control concept, but replace it. Haeusler’s previous system consisted of a separate CNC and PLC controller that communicated at the I/O level. The new control system was designed to integrate CNC and process control on one control platform.

“Our goal was to reduce maintenance costs and the complexity of the control architecture and, at the same time, optimize the process speed and dimensional accuracy of the machine,” says Michael Fabianek, manager of automation technology, IT and hydraulics, at Haeusler.

The new control platform for Haeusler’s “Bend-IT Swiss Technology” consists of a 19-inch Beckhoff (www.beckhoff.com) Panel-PC from the CP62xx series with Windows XP Embedded operating system, TwinCAT PLC automation software, and an EtherCAT fieldbus system. Haeusler uses proprietary software for the NC controller, the core of which is an HMI based on Microsoft .Net technology and programmed in C# with integrated 3D visualization.

“This ‘virtual’ machine offers both NC and CNC functionality and covers all axes,” says Fabianek. “We use one processor core of the dual core CPU for the user interface (HMI) and data management, and the other core for PLC and motion control (NC or CNC).”

The multi-core technology used in the new control system enables Haeusler to present a three-dimensional animated representation of the machine that displays all movements and allows the operator to work more intuitively, thus significantly reducing the training period for new machine operators.

>> Automation Possibilities Using System-on-Chip FPGAs: Click here to learn three examples of potential new system designs that are now possible with the wide availability of system-on-chip FPGAs

Another machine builder, EUROelectronics, based in Nave, Italy, was asked by a customer to design a closed-loop hydraulic cylinder control system for a die-casting press machine.

Position and pressure control of a hydraulic cylinder is a common application in the industrial automation field, but the precision control of such systems has traditionally presented significant challenges because of their high speeds and pressures. In this EUROelectronics application, the cylinder moves over a software-defined trajectory with specific velocity and acceleration profiles that must guarantee accuracy and repeatability up to a maximum speed of 10 m/s. For reliable control of cylinder braking and acceleration, the closing of the loop must perform at 1 kHz processing rates. Essentially, the control system directs the cylinder position to track the velocity and acceleration trajectory values entered by the operator. The operator can control the cylinder movement through a proportional, integral, and derivative (PID) algorithm.

To deliver on these requirements, EUROelectronics used National Instruments’ (www.ni.com) LabView FPGA module and CompactRIO hardware. An encoder interface designed for the task was implemented in the FPGA to measure the cylinder position while programming the system in LabView.

Using an FPGA allowed for encoding positions signals to be handled directly from the sensors. No intermediate processing or amplification device was required, thereby reducing noise and increasing processing speed.

In a process cycle faster than 1 ms, the valve position is measured and speed is calculated as both are compared to the set point. Movement is corrected using a PID algorithm. To keep the hydraulic circuit balanced, pressure values in the front and back of the cylinder are simultaneously controlled to avoid instantaneous peaks.

The CompactRIO real-time program, serving in the place of a traditional programmable logic controller, manages the machine interface. In addition, by using the CompactRIO Ethernet port, the embedded

LabView system is able to communicate with the SCADA system, allowing an operator to define the injection profile for the cylinder in two different ways: by inputting numerical values or by drawing the profiles interactively using a graphical procedure. The operator also can set various parameters required to perform the machine cycle, including position, velocity, pressure and time.

What Embedded Technologies Do for Automation
After reading just these two abridged case studies, it’s easy to see how embedded technologies are already dramatically changing the face of automation. So let’s look more closely at what these technologies are and what they do.

>> System-On-Chip Using ASICS: Click here for more information

One of the biggest microprocessor advances to occur recently in the field of automation, according to Suhel Dhanani, senior strategic manager, Industrial Automation Business Unit at Altera (www.altera.com) (a San Jose, CA-based supplier of chip-based logic systems for use by automation device and semiconductor manufacturers), has been the availability of high-performance ARM processors at a low cost with an efficient power envelope. Dhanani says this has resulted in the availability of a large line of microprocessor variants from companies like Texas Instruments and Freescale as well as new devices from FPGA vendors such as Altera and Xilinx.

With FPGAs now able to use technologies such as the dual Cortex A9 running at 900Mhz, this allows automation vendors to develop new levels of customizability or market differentiation for their products.

“PLC vendors need a custom or unique blend of peripherals and interfaces, most of which have traditionally been implemented in FPGAs,” says Dhanani. “Likewise, drive vendors need to implement different sets of fieldbus or industrial Ethernet protocols with different encoders and pulse width modulations.

That’s why suppliers of drive and PLC technologies need custom logic implementation in addition to the microprocessor unit. The integration of a high-performance industry standard ARM core with a low-cost FPGA built around a 28nm low-power process not only provides the potential of a single chip implementation, but also high performance within a low power envelope.”

Dhanani adds that as automation vendors integrate these system-on-chip FPGAs, we should see smaller and lower-power PLCs, drives that can adapt to any industrial Ethernet or fieldbus protocols, and intelligent distributed control systems running standard IEC-61131 control software.

While the higher processing performance of these new components might provide faster loop rates, higher channel density or the possibility to synchronize more motion axes within one controller, the biggest impacts for the automation industry could be in the combination of multiple new technologies within one system and open access to these components to run custom software. 

Christian Fritz, senior product manager for Advanced Machine Control and Robotics at National Instruments, says a microprocessor architecture recently announced by Xilinx brings this concept to life by combining a multicore ARM processor and an FPGA on a single chip.

The combination of a multicore processor and an FPGA within one embedded system provides manufacturers with an off-the-shelf-system that allows hardware customization through a programmable hardware chip. “This technology, often referred to as reconfigurable I/O technology (RIO — as in National Instruments CompactRIO), allows system integrators and machine builders to create automation systems that include custom communication protocols, high-speed control algorithms, advanced timing and triggering, embedded vision algorithms, and custom motor control algorithms without the need to build custom hardware,” Fritz says.

B&R Industrial Automation (www.br-automation.com) began using FPGAs in its product designs several years ago, mostly in its intelligent IO modules and drives. Robert Muehlfellner, director of automation technologies at B&R, says that much of the “out-of-the-box connectivity B&R offers in its products has been enabled by FPGAs.”

Muehlfellner also spoke about B&R’s use of FPGAs for high-speed data processing at the module level. As an example of this, he mentioned condition-monitoring modules that use accelerometers on machines to detect problems such as imbalances and bearing failures. Using FPGAs on these modules eliminates the need for preventive maintenance software based on a time schedule because it can let you know what’s likely to happen using real-time data right from the machine.

“We embedded this capability in our controller firmware so you don’t have to extract raw accelerometer data and process it in central controllers,” Muehlfellner says. “This kind of advance makes technology easy to use and does not require heavy computations to be performed on a server; instead, it is all done on the microcontroller itself.”

This same FPGA technology allows drive-level logic to be conducted on the drive itself. By “closing the loop on the drives in this manner, the advantage is greater control precision and, therefore, fewer defects on the machine as well as increased repeatability and quality,” Muehlfellner adds.

Muehlfellner also mentioned Atom processor technology as being a big step for the industrial side in terms of adopting technology from consumer side. “Used in an embedded fashion, those processors have brought high-level performance to automation without the high price tag that you’d have with a full Core iX type technology (such as Core i3, i5 and i7),” he says.

Role of the Consumer MarketIf this review of embedded technologies in automation does nothing else, it should make clear the extent to which industrial technologies are pushed along by the consumer markets.

It’s no secret that the consumer mobile industry is driving technology to be smaller, more energy efficient and delivering higher performance, says Lee Lane, director of business development for control and visualization at Rockwell Automation (www.rockwellautomation.com). “This helps us on the industrial side because we typically have

to deliver technology in smaller packaging that needs to survive in rougher environments,” Lee says. “For example, you don’t see cell phones operating in 60 degree C, but a lot of our equipment has to routinely run in this kind of environment. Sometimes even up to 70 or 80 degrees C.”

Lee adds that having the consumer cell phone market drive power consumption down to extend battery life translates into less heat being generated by automation technologies that are typically plugged in.

“Ultimately, the big issue for industrial users is the need for reliability and long-term use. But that’s not as big of an issue for chip manufacturers,” Lee cautions. “So as we all investigate new technologies, whether from an OEM or end-user perspective, we still need to focus on reliability and long-term use aspects and verify that the technology we’re buying can support that.”

An example of how leading consumer technology is finding its way into automation can be seen in Beckhoff Automation’s adoption of the new processor series from Intel codenamed “Sandy Bridge”. This second generation of the Core i3, i5 and i7 Intel processors provides for a new CPU architecture with a higher second-level cache, a faster on-board graphic card, and faster DDR3 memory.

“Beckhoff is focusing exclusively on the Sandy Bridge processors in our new product development to ensure long-term availability, dramatically increased processing power, reduced power consumption and lower heat dissipation,” says Graham Harris, president, Beckhoff Automation.

According to Harris, the Sandy Bridge processors’ power reserves and modular multi-core architecture help expand the functionality of the automation platform to cover areas previously managed by special-purpose devices.

“Multi-core processor technology is ideal for automation, since the vast majority of machines work, by nature, in parallel and the associated control programs can also be easily integrated into single controllers,” says Harris. “Motion control, CNC, measurement technology and robotic functions are now being implemented in software and executed on a centralized CPU in addition to the traditional PLC functions.”

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