Given the promise it holds for a myriad of applications, the hubbub over wireless technology, particularly in communications, is understandable. It's equally understandable that this excitement would spill over into the realm of industrial controls. Indeed, we hear a great deal about how wireless technologyand to a somewhat lesser extent, opticalmay be the next "big thing" in industrial control.
Yet, from our perspective as well as our own personal experience, we have not seen the upsurge in the use of wireless and optical technologies in the industrial-control universe that many experts have predicted. The fact is the industrial control world still appears to be a wired world. And it appears that it will stay this way for the foreseeable future.
Is this to imply that the benefits of wireless and optical technologies can't translate to the industrial control arena? Absolutely not. It's just that the industrial-control sector possesses a unique character and carries certain nuances that sometimes preclude the early adoption of cutting-edge technology. To begin with, industrial-control products have a much longer design cycle. In the consumer electronics and personal computer industries, virtually everything changes every six months; the design cycle is extremely abbreviated. However, in the industrial control sector people are conditioned to think in terms of decades. In fact, some companies are still using 8088s running DOS.
Another critical issue is that of performance. Before deciding what type of technology to employ in a specific industry, it's imperative to define what type of performance is needed. The definition of performance depends primarily on the type of manufacturing we are discussing. For instance, engineers' have divergent opinions on what "real-time" means. In one sector of manufacturing, an engineer might tell you "hard real-time" means getting information in one-minute cycles guaranteed. In a different sector, an engineer will tell you it has to be within 10 microseconds or faster. In one area of manufacturing missing your "real-time window" might simply mean you have to wait through another manufacturing cycle. In a different sector, missing the window could mean the whole system crashes.
Costor the lack thereofis another consideration. While wireless technology is becoming increasingly affordable, an Ethernet controller, the basis of most industrial control systems, is virtually free. And from a reliability perspective, the TCP/IP protocol has many satisfied customers.
Take environmental sensor or controls, for example. A vendor might provide sensors for use in the industrial control environment that can be used wirelessly, even at a reduced cost. But the engineers don't see wireless as an advantage. The use of wires is not a big deal in a setting where devices and machines are not often mobile. The value is in providing a complete solution, rather than a wireless solution; 100% reliability is the determining factor.
Wireless does have certain limitations as well, limitations that do not outweigh the ease of maintaining an existing wired system. Wireless is geographically sensitive and can be adversely affected by noise and large obstacles. Many in the industrial control space would use a wireless solution only if it were physically impossible to implement a wired solution. In most industrial control environments, there is little or no problem running wires.
The other issue is the sharing of information in different departments or remote facilities. Once the Ethernet connection is brought into the picture and hooked up to the IT department, it's possible to not only have various departments share data live, but to also monitor factories in other parts of the world, from data being sent over the line. Ethernet and Internet may sound like old news, but they are ideally suited to the industrial control environment and are driving forces behind many industrial control system upgrades today.
There are other wireless technologies that have the potential to become an important part of the industrial control landscape, such as ZigBee. However, ZigBee is also a very new spec. It certainly holds promise, but it may be some time until it truly catches on. ZigBee has been debated as a potential competitor with Bluetooth. Although, the popular view today seems to believe the two technologies have unique strengths due to the differences in architecture that will allow both to survive. However, Bluetooth has taken years to get its legs in the PC and Consumer Electronics markets. Markets that are much quicker to adapt new technology. ZigBee will likely have a similar ramp or longer.
While we do not see the wholesale adoption of wireless technology in the industrial-control sector, we do see certain wireless applications taking hold. In particular, we expect to start seeing wireless technology being used more and more in the mobile devices that interface with the industrial-control systems. Whether it is notebooks, PDAs, scanners, and other handheld devices or the like, wireless will increasingly be used.
So, if wireless and optical technologies are not are not quite ready to invade the factory floor, what will be the next technological wave to sweep over the industry? Frankly, in our estimation, the true advancement in industrial controls lies in the tighter integration of the various add-ons that allow user to become more creative. Embedded processors now integrate onto a single chip a variety of components, such as graphics, networking, and serial communications, that would have had to have been acquired separately and then integrated together. The highly integrated embedded chips available today increase reliability, lower costs and power consumption, and lead to smaller form factors and shorter hardware design cycle. They also provide components to engineers that they might not have had to time or expertise to design in. Ultimately, this provides a solution that enables industrial control engineers to brainstorm about the direction the industry may go. In other words, tighter integration inspires creativity.
As an example, we know of a customer who was migrating an industrial box designed 12 years ago. Its user interface consisted entirely of toggle switches and LEDs. Now they have a full-blown, 32-bit processor running Windows CE and have made it Web-enabled. In addition, they have superb color graphics they can create impressive histograms, and more. Web-enabling the box allows it to be used by technicians who are not even located in the same facility. Low-cost integration inspires them to do new things. You may get a component that provides real-time data but also UI as well. Once in place, the user might say, "What else can I do with this?" The big thing now is also connectivity.
It's interesting to note that the technology of manufacturing and the technology of industrial controls advance independently. If you look at how technology gets rolled out in the manufacturing environment, it's very infrequent that things all come in at once. There are myriad systems cobbled together on old technology. They were probably put together 15 years ago with a PC running 286 processors. As the technology moved along on the manufacturing side, the processors didn't necessarily keep step. What started to happen was that the platforms they developed ran out of legs, they were still developing on the DOS platform, and they needed to buy a new printer. But, they couldn't find a printer that met their requirements and had drivers available. Even though their manufacturing environment stayed the same, they may be forced to make changes on the industrial control side simply to get a driver for a new printer. Thus, an advance on one side doesn't predicate an advance on the other side.
What does all this mean for the manufacturer who today is looking for a new industrial control system? As you look at the hardware and software platformsas well as the vendors who deliver themit's prudent to look for a platform that is going to be around for awhile and is designed for long-term reliability. You can get more technology now because it's tightly integrated and offers more usability. As a vendor, you can get a little more into the bells and whistles. Plus, you can differentiate yourself by how well you understand the vertical market that you are serving.
The industrial-control arena is always a year and a half or longer behind cutting-edge technology. Therefore, it's important to ensure that the components a customer purchases are going to be around for a long while.
Moreover, we are seeing the use of off-the-shelf hardware and operating systems more and more, not proprietary hardware systems. Previously, the approach would be to "roll your own" proprietary system, but those days are rapidly fading away. For our clients, we will be designing and running systems more on the operating platforms we know today, so our client can worry more about manufacturing than designing systems and implementing new technologies.
About the Authors
Dave LeClair is Vice President of Technology at Vibren Technologies and Steve Hastings is the Assistant Vice President for Engineering, Embedded Systems, at Vibren.