The role of simulation in manufacturing has expanded in recent years. Some manufacturers are using simulation to make business decisions, since the production numbers in the simulation have become more reliable.
One company even used simulation to close a sale with General Motors Corp. “The biggest simulation we’ve done has been a feasibility study for GM,” says Murray Fulmer, corporate simulation specialist at Flex-N-Gate, an automotive supplier in Urbana, Ill. “We had to build GM’s entire Oklahoma Ultra Paint system and process every part that’s currently painted there.” The challenge for Flex-N-Gate was to double the line speed GM was using to apply paint to plastic parts, a specialty at Flex-N-Paint.
GM wanted to award the contract to Flex-N-Gate, but the automaker wasn’t convinced the supplier could handle the increased line speed. “We had to prove that the robot controller could do the job,” says Fulmer. “The simulation showed the paint being applied, and it showed the robot’s speed. It wasn’t just math. The line was moving at the speed that we said we could move.”
GM was favorably impressed—both with Flex-N-Gate’s ability to paint the plastic parts quickly, and with the quality of the simulation. “The simulation won the day,” says Fulmer. “It was the next best thing to having GM engineers watch the actual paint line. They knew that what they were seeing was valid.”
Simulation and modeling for automation has come a long way in recent years. Now, manufacturers are using simulation for business purposes. While Flex-N-Gate used simulation to close the sale with GM, other manufacturers use simulation for supply chain planning. If you know how many widgets are coming off the line, you know where and when you need equipment to move it around. You can also predict delivery schedules. Design engineers are using simulation to alter their designs to make products easier to manufacture. And companies are now creating simulations of entire plants before the plant is built or refurbished.
One recent trend is the use of simulation to train plant personnel. There are two main areas where simulation has helped in training. In one, simulation allows less skilled workers to practice and gain experience “operating” plant equipment before taking the reins in the real world. In another, simulated operation offers an accelerated form of training. “Our input/output (I/O) simulation software provides a shortcut to training,” says Stephen Perron, sales and marketing manager at Famic Technologies Inc., in Laurent, Quebec, Canada. “The training materials are created right from the simulated manufacturing design.” He notes that training is a secondary use of simulation, but the savings it produces are considerable.
Sharing all around
Another recent development in simulation mirrors progress in other areas of computer technology: standardization of data. “One of the trends in simulation is the ability to share data. People are sharing data in many directions, from product design and manufacturing to robot simulation and ergonomics,” says Peter Schmitt, vice president of marketing for Delmia, a simulation product from Dassault Systemes Group, in Paris.
Three-dimensional modeling is also gaining ground in manufacturing simulation. “We did a survey of 1,200 manufacturers. In 2003, 38 percent of manufacturing design was done in 3-D. In 2004, 51 percent of manufacturing design is in 3D,” says Bob McGill, director of business alliances at SolidWorks Corp., a simulation software company in Concord, Mass.
McGill notes that 3-D modeling first caught on in the aerospace and automotive sectors. “Three-D has been big in welding fixtures in the automotive industry,” says McGill. “You model the robots in 3-D, then select the place for the weld and tell the robot to do it along those lines.” As for pressure and the robot’s maneuverability, those parameters are built into the simulation delivered by the robot manufacturer, so you can’t inadvertently tell the robot to do something that it can’t do.
Once a company has its manufacturing process fully simulated, it becomes easier to take a product design and see how well it works in a manufacturing setting. Since the design and manufacturing are not yet “live,” there is an opportunity to turn back to the design engineer and request changes. “Simulation is being used in process-driven product design,” says Amir Livne, vice president of business development and strategy at Tecnomatix Technologies Ltd., in Israel. “Manufacturers are saying, ‘Don’t design a product and then figure out how to manufacture it.’ Early on in the life of the product, you look at the simulated manufacturing process, and see that the product can be adjusted for manufacturability.”
The ability to alter a product design prior to manufacturing in order to make the entire process work more smoothly offers big potential savings over the traditional design process. “It’s called front-loading. You identify the snags in manufacturing through simulation and you plan on how to overcome those snags,” says Livne. “Doing it the other way—designing the product, then manufacturing it—takes a lot of time. With front-loading, you design the product so it works well in the manufacturing simulation.”
In addition to using simulation in design, production and training, the technology has also taken on a role in management decisions. “Simulation is becoming a management tool since the results of the simulation are pertinent to making significant business decisions,” says Vivek Bapat, product marketing manager for Arena simulation software at Rockwell Software, a unit of Rockwell Automation Inc., in Milwaukee. “The management team can look at the production metrics, productivity data and financial metrics. The simulation can tie the production metrics to the financial metrics.”
Simulation is also being used end-to-end, showing how everything in a plant works together over a designated period of time. “We have been involved with customers such as Coca Cola and GM to make changes in their lines. The simulation is an emulator for real equipment,” says Matthew Hobson-Rohrer, director, aerospace and defense, at Brooks Automation Inc., in Chelmsford, Mass. “We can simulate at the PLC (programmable logic controller) level and all the way to warehouse management and other supervisory systems.”
In one instance, the plant simulation was actually giving plant operators insight into where and when they needed warehouse equipment. “We worked with a major beer producer to implement a new warehouse management system. We built a model of their entire four-story warehouse,” says Hobson-Rohrer. “We simulated an entire week of manufacturing and showed the company where potential problems might occur. They could see that on Wednesday afternoon, they would need some extra forklifts on Dock 2, for example.”
One area where simulations of the entire plant are getting traction is with new plants or newly refitted plants. Before manufacturers determine what equipment they need and where it should go, they simulate the plant’s entire operations. “The dynamic simulation provides a model for a new plant to make sure the plant is designed properly,” says Marty Israels, marketing communications manager of Honeywell Process Solutions.
Honeywell has a tool called Shadow Plant, which mimics the plant’s operations. The simulation helps with training as well as planning. “Shadow Plant looks at pumps and valves and it will simulate the control of the heat valves,” says Israels. “Engineers use it prior to starting up a plant, and operators use the simulator just like a flight simulator to learn how to properly start up, run and shut down a plant. You get the feel of running the actual plant.”
See sidebar to this article: Simulation is routine at GM and P&G
