Virtual Bottle Track Wins Race
Figure 1: Setting up and running a physical experiment such as a bottle race track can take months and thousands of dollars, but P&G reports that a virtual track can provide the same feasibility data in just a few hours. ARC Advisory Group and Procter & GambleSimpler Models, Better Robots
Similarly, programming robots and their complex motions never has been a picnic, but computer-aided design (CAD) tools and early simulations used to validate designs also evolved to make implementing robotics easier, according to Andy Jones, general manager for Applied Manufacturing Technologies' (AMT, www.appliedmfg.com) automotive business in Orion, Michigan. AMT is a complete manufacturing and engineering systems designer and builder, mostly for discrete machines and robotic applications.
"AMT's owner started 21 years ago when offline programs were just beginning to be added to robots," says Jones. "Since then, data handling has grown to process far more information, so CAD and other data translates more seamlessly. This means it's easier to program and validate robots off-line in a generic language and then pour that knowledge back into plant-floor robots in their native language. Likewise, simulation environments are getting more generic, and so simulation packages can program each robot controller closer to how the robots will run in the real world. Basically, the simulation environment talks to the emulator for each robot manufacturer.
This means the simulation runs just like a real robot. Ten to 15 years ago, there was about a 20% difference in cycle times between the simulation and real operations. Now it's a fraction of 1%."
Jones adds that AMT sees simulations now being used how they're supposed to be, namely for early process development and identification of what users want the robot to do and how the system should look, for mechanical design and CAD functions, and for communicating ideas to enterprise-level managers and customers. "Simulation can do virtual prototyping, but then it can also verify performance and throughput," adds Jones. "We can link a simulation model to actual PLCs, validate logic before building anything, and then make changes later when new capabilities need to be added. When you think simulation has reached its full capabilities, something new comes along."
Better Math = Closer Reality
At the root of all simulations, driving them and their software's increasingly sophisticated capabilities and new applications, is a pile of mathematics and faster calculations. What's sometimes lacking is user understanding.
"A good simulation can check that all your inputs and outputs act as they should, but people still think they have to do manual trial-and-error with devices such as VFDs," says Neil Koepke, marketing manager, Yaskawa America's Drives and Motion division (www.yaskawa.com). "They don't think you can simulate hardware. So, four years ago, we developed simulation software for our 1000 Series products. Now users wire drives to the software, connect power, run programs and punch keys as if they were using real equipment."
Really Simulated
This article provides some evidence of simulation software has big savings and productivity potential for machine builders and customers alike. What have you learned? Discuss your simulation projects and pitfalls, real or simulated, at
www.ControlDesign.com/realsimulation.
Similarly, to increase the realism of its offshore, quayside and gantry crane simulators, Applied Research Int'l (
www.arisimulation.com) in New Delhi, India, recently worked with machine builder Electropneumatics & Hydraulics near Pune, India, to add a three-axis motion platform based on Baldor Electric's Powerlink- and Ethernet-compatible drives with its MicroFlex e100 ac servo drives in basic Ethernet mode. The drives allow the simulator's replica cabin to move in synchronicity with computer-generated images, better emulate the real cranes and give trainees a more realistic, fully immersive environment where they can get truer hands-on experience in moving containers and other bulk-handling tasks.
Virtual Snacks, Coming Attractions
Once simulation improves a user's machines, production lines and packaging, they might look for other items to simulate—even potato chips. Lange says P&G now makes its Pringles potato chips so fast—about a billion every few hours—that it recently simulated the aerodynamic forces acting on the chips to keep them from flying off its production machines and to better coat them with seasonings.
"We found that air pressure was building up on the front and back edges of the chips, and we had to find a way to keep them on the line, so they wouldn't end up as pig food," says Lange. "Distributing seasonings evenly was an even more serious problem. The simulation showed that we couldn't just blow the seasonings into this airflow, and so we learned that we had to spray them on instead."