Wireless LANs are being installed on Navy warships to free up manpower, reduce crew sizes and improve monitoring of a range of mechanical and electrical systems.
The installation effort, dubbed Total Ship Monitoring (TSM), lets Navy crew members check and control systems from computers anywhere onboard. It's an extension of the Smartship refitting and redesign program the Navy launched in 1996 to let captains command their ships from anywhere onboard.
The USS Howard, a guided-missile destroyer commissioned in 2001 and assigned to the Navy's 3rd Fleet, based in San Diego, is being outfitted with specialized wireless gateways based on the IEEE 802.11b wireless LAN standard. The gateways, which defense contractor 3E Technologies International (3ETI) designed and built, use a radio link to interconnect sensors on gear such as pumps and motors with back-end data processing applications.
So instead of laying hundreds of feet of cabling by cutting through a steel ship and adding weight to the vessel, the radio link makes possible much faster and less-disruptive deployment of the sensors.
A series of mockups and simulations have proven the TSM system works on land. But the critical phase is proving the TSM will work under the demands of combat and life at sea.
"[The Navy is] moving from an industrial-based, manpower-intensive work force, to a new realm of information technology," says David Bartlett, the Navy's Smartship science and technology manager. "There's a lot we can do with IT for automation." TSM is being incorporated into new combat ships being launched and into existing ships.
TSM uses 802.11b wireless LANs, sensing devices attached to things such as motors and pipes, and programmable logic controllers, which are special computers that have long been used to control a range of civilian factory machinery, such as cardboard bailers, heating/air conditioning equipment and conveyor lines. "It's been difficult to tie all these pieces together in an integrated fashion," Bartlett says.
Wireless is now a key element in TSM projects. Data from scores or hundreds of sensors can be fed back to access points and servers without the cost, weight and delay of wiring or rewiring steel ships.
The wireless LANs will change the way crew members perform their jobs. "Today, they have to do rounds, every 45 minutes or two hours, for example," says Benga Erinle, director of government operations for 3ETI. "They're checking equipment, machinery and filling out and signing paper logs."
The TSM system is intended to do all this automatically.
"It goes beyond simply gathering information," Erinle says. "We also use programs for diagnostics and prognostics, based on the data. If a critical system is going to fail, we'll pick that up and alert the chief engineer that this is pending."
The TSM system also will change the Navy's longstanding practice of time-based maintenance - of replacing or tearing down machinery after so many hours or days of use.
That is very labor-intensive and not very cost-effective," Bartlett says. TSM will funnel megabytes of real-time data into sophisticated algorithms that can predict accurately when repair work needs to be done. In the past, the Navy hardwired analog sensors into programmable logic controllers and wired these into a computer system called the Integrated Condition Assessment System (ICAS). 3ETI designed an eight-channel analog-to-digital converter, called the 3E 555I gateway, that acquires the data and optimizes the 802.11b radio connection to a remote wireless access point, which links via a wired LAN to ICAS.