San Jose, CA By building atop a standard intended for cell phones and computers, a sensor manufacturer hopes to bring wireless networking to the industrial market.
Crossbow Technology Inc., a maker of micro-mechanical silicon sensors, recently unveiled a wireless architecture that provides radio links between sensors and machine controllers. Known as CrossNet Wireless, the new system takes analog data from sensors, translates it, and sends it through the air to network controllers.
The technology is expected to appeal to industrial controls engineers because it could ultimately allow them to eliminate tens of thousands of feet of wiring from the average manufacturing plant. That, in turn, would enable them to reduce labor and cut costs. Factory automation engineers estimate that installation of wiring for a network can cost from $50 to $100 per foot. "Talk to anyone inside a big factory, and they will always complain that once a factory is set up, wiring is a huge issue," notes Rudy Mui, vice president of marketing for Crossbow Technology Inc.
Crossbow proposes to solve that problem by using existing Bluetooth standards, which call for wireless links between computers, mobile phones, and other portable consumer devices. By doing so, the company says it can cut the high potential cost of wireless systems. Previous systems, which included both a transmitter and receiver, cost as much as $10,000 per node. "We just piggybacked off Bluetooth," Mui said. "That way, we didn't have to worry about developing a receiver."
Crossbow's system consists of a small electronics node that mounts near the sensors. The node, which costs $1,295, contains four sensor ports, a Bluetooth radio transmitter, and an ARM microprocessor with embedded software.
The company says that the technology can be used with a variety of different kinds of sensors, including those that measure temperature, humidity, pressure, strain, torque, or virtually any other parameter that can be converted to an analog voltage output. It cannot, however, be used with sensors that create a digital output.
To encourage adoption of the wireless concept in industry, Crossbow has already teamed with several corporate partners, including: DataStick Systems (Santa Clara, CA), which makes Palm Pilot data acquisition systems; Extended Systems (Boise, ID), a provider of wireless connectivity products; and SmartSignal Corp. (Lisle, IL), which makes equipment condition monitoring software.
"With Bluetooth technology, a maintenance person with a Palm Pilot could walk around the factory and communicate with all the sensors," says David Brochu, vice president of sales and marketing for SmartSignal Corp. "And all the information you need could be captured by the Palm Pilot."
Initially, Crossbow engineers expect the technology to be adopted by manufacturing enterprises that must make frequent changes to their machinery. By doing so, those companies could reduce downtime and cut costs, because machines would not have to be re-wired every time a change was made.
Facilities with existing infrastructures and wiring are unlikely candidates for the new technology. "Our system won't obviate wiring," Mui says. "For now, we are looking at complementing wired systems, not replacing them.