ISA 2012 Automation Week
Track: Wireless
Tuesday, September 25, 3:15pm-4:45 pm, Room 205A
Mike Fahrion
Director of product management, B&B Electronics
Be it the transition from nomadism to agriculture or the Industrial Revolution and the subsequent shift to global urbanization, it is easy to look backwards and see how technological innovation inevitably reshapes human societies. In retrospect, the changes seem obvious and predictable. But things get a bit more complicated when it is your own world that is changing.
Bob Metcalfe, often called the “Father of Ethernet,” stated that the value of a network increases proportionally with the square of the number of compatibly communicating devices. Moore’s Law states that the number of transistors on integrated circuits doubles approximately every two years, roughly doubling processing power. Together, they mean that network devices will continue to become smaller, more intelligent and more numerous.
At the same time, devices are making strides in power efficiency, with remarkable gains in Wi-Fi and Bluetooth 4.0, in particular. Combined with ongoing improvements in power sourcing and storage for low-power applications, it means devices will become increasingly independent.
Small, smart, independent wireless devices will make it possible to network-enable more and more “things” and locations that were once inaccessible—but only if those remote devices are less dependent upon external power. That consideration is suddenly pushing power management to the forefront of network architecture and design. Power budgets and power constraints are beginning to dictate system topology and technologies.
The same concerns also affect node design. As the network edge expands to include more and more self-powered devices in remote locations, the remote nodes will have to be less dependent upon constant communication. In the past, an upstream device (a PLC or controller) would poll as fast as was physically possible. Conserving power was not important.
The data might not change 99.9% of the time, but the system intelligence was centralized at the controller and continual polling was unavoidable. Intelligent nodes will make that waste of power unnecessary.
Intelligent nodes will make efficient use of their wireless connections. They will use internal business logic to determine whether they have anything useful to report, and they will stay off the network until they do. They will use situational awareness logic (the state of the network, the state of surrounding nodes, power availability, and the state of the system) to manage local device behavior.
The central controller, of course, will still need to know whether a node is nonfunctional or merely being quiet. (Let’s say that a water tank is half full, has been that way for days, and the remote sensor is silent because it has nothing of interest to report.) In the old network model, the nodes would be required to remain in constant communication, eating away at the power budget the entire time. But a “smart” node can be given a simple "heartbeat" function instead. By pinging the master every now and then, it lets the master know that while it may be one very dull node, it is not a dead one.
Fahrion will describe the techniques that today’s system/node architects are using, such as reporting on exception, statistical modeling at the node, situational awareness, the store and forward model, heartbeat/health reporting mechanisms, and security mechanisms.
Figure 1.
He will take a look at new technology-enablers like IPv6, Wi-Fi, Cellular, and 6LowPAN. For example, Wi-Fi wireless access points could keep mobile M2M equipment connected as it moves around a plant in shipping/receiving applications (Figure 1). The cellular telephone system provides another way to network remote sites and M2M equipment, with very good (almost great) reach. Wireless carriers are eyeing M2M as a strategic growth market, with data plans becoming more M2M-friendly.
Fahrion will present several case studies in which GPRS/EDGE and UMTS/HSPA+ cellular routers were paired with security cameras, and photo/motion/meteorological sensors for effective remote monitoring/control in interactive traffic control (Figure 2), public lighting (Figure 3), and energy management (Figure 4) systems.
Figure 2.
Figure 3.
Fahrion will also discuss the impact and future of IP networks and the ways in which networking will expand, including some of the things that will be happening way out at the network “edge,” where network-enabled devices will be performing new functions in increasingly difficult environments. He will examine some of the problems that will be encountered when new technologies are deployed, as well as their solutions. (He will also discuss the means by which legacy equipment can be induced to keep up with the times.)
Figure 4.
The trends indicate that virtually everything will soon be network-aware, from simple household appliances to sophisticated M2M industrial devices. Fahrion will help you prepare for the changes.
