Before General Motors Corp.'s architects drew the final lines on the blueprints for two new auto-assembly plants under construction in Lansing, Mich., and Russelsheim, Germany, the company used some of its most cutting-edge 3-D virtual-reality design tools to decide the size and shape of the plants; where workers, robots, conveyors, and cranes would be located; and where to locate the receiving docks that would handle parts for production.
It was the first time GM had ever used its production-modeling design tools to design a factory, says Kirk Gutmann, GM's global product development information officer. It's likely a first in the industry, says Kevin Prouty, AMR Research's automotive analyst. "What GM is doing with factory modeling is more important in the long run than the digitization of design, and the company couldn't succeed without digitizing its design work," Prouty says.
Traditionally, assembly-plant design has been more art than science, with a billion dollars in construction costs riding on the artistry of the designers. During the plant-design process, a mind-boggling amount of data has to be considered--how parts move into a plant, how they move onto the assembly floor, how they're moved into place for assembly, how tools are used by workers, and how robots perform their tasks.
All those factors determine how quickly a car can be built and how many cars can be built in a day. Getting it right maximizes the number of vehicles that a plant can produce. A mistake serious enough to shut down a production line for a change might cost as much as $10,000 a minute, Prouty says. That's why GM rolled out a component of EDS's E-Factory Suite named Jack to help in the process of building the two new plants.
Gutmann says GM had used Jack to model the process of assembling automobiles in eight of its 53 plants, and results have been good enough that it seemed natural to use the tool in designing the two new factories. One of them, the plant in Russelsheim, is designed with a new idea in mind--that different car models can be built on the same production line simultaneously. GM calls that a flexible production line.
Because different models will be built on the same assembly line at the same time, Gutmann says, the German plant is far different from a typical plant--from the plant's shape, the way the receiving docks work, and the ways parts and materials are moved to the assembly line.
Using virtual-reality tools, every step in the process can be timed to the second, and bottlenecks are easier to find and repair. Because GM uses 3-D modeling tools, rather than the two-dimensional tools most manufacturers use, it can see where material-handling systems will interfere with conveyor lines and where robotics will conflict with people who have to work on the line, he says.
"We can get all the way down to where we can see that a worker has to support something heavy with one hand, guide it into place with the other, and still use a hand tool to fasten it in place," Gutmann says. "If it's really hard to position the part, before we actually build the line we can plan for a way to position it so the worker doesn't have to hold so much weight."