General Motors makes wireless LAN mission critical

General Motors is installing wireless local area networks in all 25 of its North American assembly plants to improve efficiency.

General Motors is installing wireless local area networks in all 25 of its North American assembly plants to improve efficiency.

GM will, initially, use the wireless LAN infrastructure to track materials and replenish parts at stations on its assembly lines.

But once the wireless LANs are in place, according to Cliff Triplett, global information officer for manufacturing and quality at GM, they can be used to support a wide range of other applications. These include access to computer-aided design drawings and plant configuration information, which Triplett called a "virtual factory" database.

Larry Graham, global manager of manufacturing technologies for GM, said the factory wireless LAN infrastructure would bring about a "quantum change" in the ability of GM to send and receive information to and from workers and systems in the manufacturing environment.

"It provides you with agility and flexibility that did not exist before," Graham said. GM plans to standardise on Wi-Fi, or 802.11b, wireless LAN technology in all of its plants, he added.

But Graham said GM expects a quick payback on its investment in less than a year. He declined to elaborate further on the financial details.

Jack Maynard, an analyst at Aberdeen Group, said the fact that GM expects to recoup its investment so quickly indicates that the company had "a real problem" with locating parts efficiently within its plants.

Maynard added that GM could use the wireless LAN-based materials management system to change its manufacturing operation drastically to a build-to-order model.

GM has already equipped up to 100 forklift trucks with wireless terminals in each plant. In its New United Motor Manufacturing plant in California, which it operates jointly with Toyota, GM has installed a wireless location system that works with the wireless LAN.

When workers need to replenish parts for their station, they press a button on a wireless pendant at their workstation. The request is displayed on a screen on the forklift, showing the location of the worker and the materials required. GM's Triplett said he views vehicle-tracking information as another high-priority application for the wireless system.

GM rivals Ford and DaimlerChrysler both operate extensive wireless LAN networks at their North American manufacturing plants, but neither has plans to install an infrastructure equal in scope to GM's.

Jim Buczkowski, director of manufacturing and supply chain IT at Ford, said the company has installed wireless LANs at all 21 of its North American assembly plants, but with zoned rather than plant wide coverage.

Ford uses wireless LANs in the yards of all its plants to control and manage finished-vehicle inventory and has experimented with installing wireless terminals on forklifts, Buczkowski said. However, the company had not been able to justify a business case for wide-scale rollout of wireless terminals on forklifts, he said.

Elive Likine, manager of wireless communications at DaimlerChrysler, said the company has older wireless LANs that operate in the 902-MHz band that are used to support yard operations. The car makerhas also installed 802.11b wireless LANs, which operate in the 2.4-GHz band, at some of its plants to support specific applications such as "end of line" testing of electrical components.

DaimlerChrysler plans to stick with the 902-MHz wireless LANs for now because "we do not see a business case to shift from 902 MHz to 2.4 GHz," Likine said.

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