Although predictions vary as to when the adaptation will occur, there's little doubt that the factories of the future will be controlled by wireless technologies. Until recently, wireless connections have been expensive, slow, and subject to the suspicion that they could be easily tampered with. As a result, industrial controls have remained hard-wired. The wireless links of today, however, are faster, more economical and more secure. The age of the wireless factory is fast approaching.

One wireless technology that is nearing the level at which industrial application could be cost-effective is Bluetooth. Named after the Viking king who unified Denmark and Norway, Bluetooth radio-wave chips are designed to provide voice and data links between the devices in which they are imbedded and all sorts of handheld computers, measuring and metering equipment, telephones and appliances. Initially making its name in the personal high-tech gadget market, Bluetooth has become an industry standard for short-range wireless communications and networking that combines robustness, small size and low power consumption.

Industry insiders such as Sandy Harper, a senior research and development project engineer at Parker Hannifin Corp., an early adopter of Bluetooth technology, believe the chips could provide the next big productivity leap in industrial automation and lean manufacturing. Harper says that, "The possibilities of these wireless technologies to add value in monitoring, control and industrial-system configuration are tremendous." Commenting on the configuration aspect, Harper explains that, "A key benefit is the elimination of cables and connectors from the manufacturing floor." This could be particularly attractive to industries such as food and pharmaceuticals whose operations require ultra-clean environments. Harper also points out that, "Systems would be easier to set up," adding that the typical industrial environment has thousands of places where wireless sensors could be used.

One aspect of industry that wireless technology is sure to improve is maintenance and trouble-shooting. The myriad of wires running to a central controller, along with air and power lines, can make locating a particular faulty wire an exercise in futility. In addition, it facilitates troubleshooting difficult-to-reach devices like hydraulic and pneumatic filters. A tiny Bluetooth unit in a filter would enable remote monitoring with a pocket computer. This could be especially advantageous inside plants where moving machinery or hot temperatures pose hazards for workers trying to monitor equipment. Furthermore, engineers could use wireless personal digital assistants (PDAs) to automatically link to a master data system if they required additional information on a machine.

Bluetooth could also be used in remote or mobile sites such as ocean ships or drilling rigs to monitor the operations of engines, motors and other equipment. Having said that, Bluetooth chips are not quite resilient enough to operate in the most extreme environments. For instance, they have trouble withstanding high engine heat and are disabled by radio wave interference.

Cahners In-Stat Group forecasts the market for Bluetooth-enabled equipment to hit $5 billion by 2005. These forecasts assume that the bulk of the opportunities will be in telecommunications, personal computing and office/retail environments. But many companies, including Parker Hannifin, see an even greater potential demand in industrial markets. Upbeat insiders predict that Bluetooth will replace every device with a tethering connection cord from bar-code readers to handheld terminals. Other conjectured applications include reading of sensors in rotating equipment and in inventory data tags attached to pallets for warehouse storage.

Sounding a much less optimistic note are builders of large industrial equipment such as machine tools. "Our customers don't want to pay the extra costs," says Robert Gardner, a spokesman for the Association for Manufacturing Technology, a machine tool builders group in McLean, VA. He maintains that tool builders don't see much advantage in adapting wireless technology to large machines that seldom need to be moved once they are installed. Consequentially, machine tool manufacturing may be one of the last industries to go wireless.

There are other wireless technologies currently being considered for industrial purposes. Wireless Local Area Networks (LANs) are seen as having great potential although they still have some wrinkles that need to be ironed out. The designated purpose of wireless LANs is to connect mobile computers and handheld devices directly into the corporate LAN. For example, imagine goods arriving at a company's receiving dock for just-in-time manufacturing. These goods are unknown to the manufacturing operation until they are received and entered into inventory. Oftentimes, the receiving room operator uses a handheld bar-code scanner to gather the data from the shipping labels on the received merchandise. When the bar-code reader itself is a terminal on the wireless LAN, the bar-code readings can be translated into database transactions, making the received merchandise immediately available for manufacturing. This arrangement would effectively reduce inventory and all but eliminate manufacturing delays from the receiving room operation.

Now for the glitches: While interoperability between different supplier devices has been an industry-wide goal, the wireless LAN standard is not sufficiently rigid for this to happen. Another problem, this one associated with its network software rather than with the wireless LAN, has to do with the "roaming" user. Unlike cellular telephones, which provide a solution for users roaming at the lowest layers of the protocol, there is currently no solution for the roaming use of wireless LANs. There is also the high cost of both network interface cards (NICs) and the access points needed to connect to the wired LAN to consider. Perhaps because of these obstacles, the wireless LAN market has not grown as fast as industry watchers previously predicted.

Another technology that, used in conjunction with wireless technologies, has the potential to transform the factory of the future is Radio Frequency (RF) tags. As Industrial Market Trends reported last month, a surge of interest in this identification technology has come from a decrease in cost, an increased range of reading and the predicted convergence between RF tags, wireless smart cards and RF electronic article surveillance tags. The convergence of these technologies would create a very large market and drive RF costs down, thus making the technology not only an attractive option but also an affordable one.

Supply chain efficiency depends on the rapid movement of information as well as the merchandise itself. Much has been written about the use of electronic forms of ordering and invoicing, but little has been said about the mechanics of getting this information synchronized with the physical items. Bar coding is the current method of choice to identify individual items or shipping containers of mixed items. But bar code reading is a manual task, not easily automated even on conveyor lines. With longer-range RF tags, ID information could be read automatically as the goods are moved to the shipping room or are unloaded to the receiving area. Furthermore, the entire electronic transaction could be contained on the RF tag itself, synchronizing the receipt of the item and the bill of materials as well.

Regardless of which emerging wireless technology moves forward the quickest to reshape factory operations, the fact is that these operations are changing. And the future direction in which industry seems to be headed is that of the wireless factory.

Sources: Automation that Cuts the Cords
MSI Magazine, Feb. 2002
http://www.manufacturingsystems.com/lnwp/frameset.asp?url=http://webpublisher.lexisnexis.com/index.asp?layout=story%26gid=1650000965%26did=453G-7JW0-00SH-33F4-00000-00%26cid=80004408

Wireless Control of Equipment to Expand in Industry This Year
Bill Roebuck
MRO Magazine, Jan. 9, 2002
http://www.mromagazine.com/article.asp?id=6219