Where It's At - WhereNet wireless technology

Automotive Manufacturing & Production, July, 2001 by Gary S. Vasilash

KEEPING TRACK OF ASSETS-BE THEY PARTS OF ENTIRE VEHICLES-CAN BE MORE READILY NONE IN THE LARGEST PRODUCTION PLANTS AND ASSOCIATED PARKING LOTS THROUGH THE IMPLEMENTATION OF A RADIO-FREQUENCY-BASED SYSTEM.

Knowing where things are--physical, actual things, like vehicles, not computer information about things--is certainly helpful for operating an efficient supply chain: Or, more to the point, a physical link in said chain, as in a factory. Which is a large part of the functionality of the technologies proffered by WhereNet Technologies (Santa Clara, CA). This is wireless technology. This is technology that is said to provide "real-time location' of products. The company, which was established in 1997, has numerous applications in numerous industries in numerous countries; one of the prime areas they've identified for implementation is automotive.

Case in point: at Ford. This is no trivial application: the implementation received one of a handful of Henry Ford Technology Awards in 2000.

HIGH-TECH KANBAN

This is the "WhereCall Parts Replenishment System," which works in conjunction with Ford's SMART parts replacement program. A key element is the WhereCall tag, a transmitter. In an assembly operation, when an operator needs more parts, she pushes a button on the tag, which then sends a signal (it uses low-power, spread-spectrum radio frequency technology), which is picked up by antennas, location processors, and then processed by software. The result of which is that the materials replenishment people get the alert that there is a request for parts. (There is even a timer so that the operator can determine whether or not the request is being honored in a timely manner.)

This is said to provide several benefits for Ford (given that it has been installed in 20 Ford plants and is scheduled to be used in many more, there must be a good return being realized). For one thing, compared to wired call systems, it is faster to set up (operators can simply affix the tags in their workstations) and a whole lot less expensive (no running reels of cable is required). And when there is a change to the line, due to either rebalancing of existing processes or because of a new product, the tags can be reused, simply associated with new parts. In addition, because there is that timing function, there is the ability to use the data to make determinations for process engineering, noting, for example, how long it really takes for deliveries.

In a very real sense, it is kanban gone high tech.

where DID I park IT...?

Ford has also installed a different type of system from WhereNet, this called the "WhereSoft Vehicle" application. Once again, there are the elements of the transponder tags, antennas, location processors, and software. But this time, instead of parts, the tags are placed in vehicles when they are in final assembly. The benefit here is that there is certainty of precisely where that vehicle is. For one thing, it makes it possible to determine if there are assembly bottlenecks. But it is especially important when the vehicle is complete and it is parked on a lot outside of the factory in the shipping yard. When it is necessary to find a particular vehicle, it can be located to within 10 feet. It isn't necessary for people to be wandering through the lot looking for just the right vehicle for, say, a custom dealer order or in case there is a quality control hold being placed on a particular group of vehicles. Apparently the ability to quickly locate vehicles means huge dollar savings through superior inventory control.

(By the way: before the vehicles are rolled off on trains or trucks, the tags are removed for re-use.)

TECHNOLOGY, BRIEFLY.

From a technical standpoint, the WhereNet engineers have developed a system that uses direct sequence spread spectrum radio frequency (DSSS RF) technology. It's not Bluetooth. It's not GPS. What you simply need to know is that the WhereTags send out low-power signals that are spread across 60 MHz. Because they are low power transmitters, the lithium batteries within them can last for years Because of the spectrum spread, there is minimal RF pollution.

So there is a beacon, sending out a signal at a set period of time. The signal is received by antennas that are installed in a known grid pattern. What happens is that the signal is received by three different antennas at slightly different times. It is known when the signal was sent. It is known where each of those antennas is located. As a result of comparing the time with the known place, the system is able to calculate where the beacon is located.

In addition to which, along with the "here I am" signal, there is as much as 96 bits of telemetry information sent, which allows additional information about what is where (e.g., what the VIN number is).

Not only does this all facilitate simple location on the screen of a PC, but it also permits displaying the information across the Web--f or extensive supply chain visibility.

There are additional applications developed for this technology. For example, there is container management: permanently tag a container and keep track of where it is and what it contains. And there is yard management, which permits knowing where trailers, tractors and tugs are at all times when they roll into a plant site.