NURI Telecom in Korea expects to bring an automatic meter-reading system-to the U.S. this year. The idea is that Zigbee-enabled meters in a neighborhood will form their own mesh network. A single controller in the area monitors gas use in real time and sends the data to a center station.

But the system is expected to handle more than just utility metering. NURI thinks the basic technology will let utilities offer services for home monitoring, fire alarms, and control of home appliances. The heart of the meter is a Zigbee communication module which NURI devised working with chip and protocol developer Ember Corp. The module will be an OEM component available for use by other companies fielding Zigbee products. The system is already working in scores of Korean homes as a governmentsponsored pilot project.


A new twist on, "I've fallen and I can't get up"

The Lusora Intelligent Sensory Architecture (Lisa) from Lusora Inc. is basically a home-monitoring system for senior citizens. Zigbeebased Lisa gear includes a light switch with a tiny digital camera (left); a pendant (center) worn around the neck; and movement tags (right), which can let the system generate an alert based either on detected movement or the lack of any movement.

Zigbee doesn't have the bandwidth to handle video. So lightswitch/camera combos deliver still images to a controller. An alert from the pendant or from one of the tags activates the camera.

The pendant includes accelerometers that detect the forces of a person falling. It also contains a panic button.

Lisa can send a warning either to a monitoring company or family member if something is up. It can be programmed to generate an alert, for example, if a bedroom or refrigerator door hasn't opened by noon.

San Francisco-based Lusora expects to offer the first Lisa devices this fall.


Not the Jetsons, but close

Control4 aims to take home automation out of the exclusive realm of the rich. Based in Salt Lake City, the company has devised an array of audio and video controls, displays, and intelligent light switches that employ Zigbee schemes. The full list of Control4 gear includes audio servers, protocol bridges, AV controls, thermostats, media management, and lighting controls.

The Control4 vision is to handle most aspects of climate control, lighting, and audio/video media through wireless controllers. Of course, audio and video signals get beamed throughout the house via Wi-Fi or other high-bandwidth protocols. Wireless control signals, however, follow Zigbee standards. The full system can pull off fairly sophisticated effects such as automatically dimming lights when a receiver turns on.

Even "kid control" is not beyond the system's capability: The press of button could conceivably power down room lights and kill any nocturnal Xbox use. The system can sense ac loads through Zigbee-enabled outlets. This lets parents tell the system to switch off an outlet after a prescribed period of video gaming.

Light dimmer switches, automated blind mechanisms, sprinkler controls, door sensors, and similar devices are scheduled for release this year. Because the components all communicate wirelessly, installation takes place without the involvement of contractors or routing of wire bundles. And an Internet connection lets homeowners keep an eye on their house or change settings from anywhere in the world.


The bugs this system catches aren't in software

System operation

One of the more offbeat applications for Zigbee networks is in catching termites. Developersat Software Technologies Group Inc., Westchester, Ill., worked with a researcher at the University of Florida to devise wireless bait stations that are each a Zigbee node.

In operation, the bait stations go into the ground at numerous spots surrounding a house. Each bait station has a special sensor that triggers when termites eat at the wood it contains. The station then signals this activity to a receiver, which sends an e-mail to exterminators.

The wireless approach beats the technique now used on several levels, say developers at STG. Existing methods force exterminators to physically check each station for activity. Termites could cause severe damage long before evidence of them could turn up during a periodic inspection. In contrast, the Zigbee bait stations monitor pest activity 24/7. And exterminators need not make long trips just to examine bait stations.


Zigbee may help you make that flight

One projected use for Zigbee is as a mechanism for more rapid processing of returned rental cars. Developer Software Technologies Group Inc. demonstrated the concept on a scale-model Mini Cooper at a recent-technology expo. But the firm thinks there is a bigger market among companies renting real cars as opposed to toys.

STG suggests making each rental car a Zigbee node. Cars pulling into the return bay would automatically upload data about odometer readings and fuel levels, as well as any service-me-now warnings from the on-board vehicle computer. STG says the Zigbee module could also carry accelerometers that would report any fender-benders during the rental period.

The firm hasn't yet signed up a customer but is shopping the idea around.


How to make a Zigbee node

A Zigbee node today can consist of as few as two ICs plus a power source and a few passive components, as depicted in this view created by Zigbee chip and protocol house Ember Corp. The two ICs, basically a microcontroller configured for the Zigbee protocol and a transceiver, will become one device later this year.

Some Zigbee nodes can double as routers, hubs, and other kinds of network hardware. But these extra duties generally don't incur extra electronics. A Zigbee controller equipped with a sufficiently large flash memory can carry out such tasks in the course of its normal operation. Nevertheless, a few applications may add another processor for computational horsepower.

There can be differences in how various vendors of Zigbee electronics approach implementation. Ember, for example, says not all transceiver makers handle security functions and encryption the same way. Approaches where software carries out encryption could potentially be less efficient than those employing special-purpose hardware.

Regardless of the functions designed into the Zigbee node, firms developing equipment for the standard have special obstacles associated with the low bandwidth of Zigbee signals. The software work for developing specific applications can be tricky. The relatively low information capacity of Zigbee makes it impractical to repeatedly download tweaks to application programs as the application evolves. So special development kits help speed things up by creating temporary connections to Zigbee controllers over higher-bandwidth channels such as Ethernet.

MAKE CONTACT:

Atmel Corp., Zigbee-compatible microcontrollers
atmel.com
(408) 441-0311
Control4, Zigbee-based home-automation systems
control4.com
(801) 523-3100
Eaton Corp.,
Zigbee-based homemonitoring systems
www.eaton.com
(216) 523-5000
Ember Corp., Zigbee transceiver chips, development kits
ember.com
(617) 951-0200
Lusora Inc.,
Zigbee-based home-monitoring equipment
lusora.com
(415) 561.6724
Software Technologies Group Inc.,
Zigbee system software and development
stg.com
(708) 547-0110
Zigbee Alliance, Zigbee vendor organization
zigbee.org