Pictures of the Future    Fall 2007

Trains of Bits and Bytes

The engineer running a Velaro high-speed train adjusts the controls on his instrument panel. Suddenly a flap opens in the floor, the angle of vision swings to the space under the train and components fly apart. Miraculously, however, the train reassembles itself.

Welcome to the virtual reality laboratory at Siemens Transportation Systems (TS) in Krefeld, Germany. Neither the train nor the engineer are real—they’re animated virtual objects. There are no flip charts in the conference room. Instead, there’s a power wall on which true-to-scale prototypes in a spatial environment generated by a computer can be observed with the help of 3D glasses and discussed. "This is a big help, for example when we’re planning installation, analyzing ease of maintenance, and conducting ergonomic studies," says Reinhard Belker, head of Engineering Process Management at TS.

The Virtual Reality (VR) system is an integral part of the development process at TS. Here, designers meet regularly to study new trains in virtual space as they are being developed and discuss them with their colleagues from adjoining units. They also meet in "collaboration meetings" with their unit’s sister production plant in Prague, in the Czech Republic, where the same system is used. At the moment, the systems are the only ones of their kind in the world.

But the VR system is only one of the innovative tools that support the purely virtual product and production development process at TS. Today, rail vehicle design proceeds from start to finish in an unbroken 3D CAD (computer aided design) process chain. Every step, from the initial concept through development, production preparation, manufacture, assembly, and documentation, is worked through in three dimensions using CAD systems.

Everyone involved works together in this virtual environment. That makes it possible to align, in real time, the stages of development reached in the main production plant in Krefeld with those in Erlangen and Kassel (Germany), Graz and Vienna (Austria), and Prague and Ostrava (Czech Republic). In addition, suppliers and service providers are integrated into the process of developing rail vehicles of all kinds, from subway systems to high-speed trains.

High-tech tools are absolutely essential in Krefeld because market demands are increasing steadily. Customers all over the world are demanding shorter development times with equal or even better product quality and a high degree of technical sophistication. "A few years ago we developed and produced a high-speed train in three years. Today, our customers are asking us to do the same thing in two and a half years," says Martin Olbrich, head of the TS Work Preparation Assembly unit.

In addition, prices have dropped dramatically as a result of fierce competition in the rail vehicle market. "These demands can no longer be met using conventional methods. What we need now are innovations, not only in terms of products but also in our production and development processes," says Belker.

Step by step, engineers at TS have achieved a unique level of technical sophistication. Since 1999, developers have designed their products using 3D technology from start to finish. In 2000 they introduced a uniform 3D administration system as well as the Virtual Reality system. In 2003 the "paperless factory," which uses virtual assembly instructions, was already a reality. In other words, before assembly workers begin to work in and on trains, they take a look at the individual work steps in animated virtual form. SAP’s Product Lifecycle Management module, which controls and documents the entire product creation process, was introduced in 2004.

And in 2006 the company put in place at all of its locations a comprehensive 3D process chain that creates digital animations during the initial design phase on the basis of 3D CAD data and carries out initial simulations. Developers design individual assemblies in 3D, which are then made available to partners worldwide. This is done using a uniform product data management system—even before a single screwdriver is picked up in the real world. To date, parts of these processes have run in parallel, allowing the initial development steps to be immediately included in planning processes at other units.

Virtual Reality Meetings. Because 3D CAD data requires lots of memory, it is not used in all process areas. Some developers work with "viewing data," which requires less memory and is cheaper and simpler to use. Here, all of the data is automatically converted to a viewing format. This is a feature that enables designers to have virtual worldwide meetings in which they can share their ideas about the current state of a project. Such meetings eliminate the need for time-consuming travel. What’s more, they make the entire development process faster and less prone to error because every developer knows exactly what his or her colleagues are doing. Of course, data provided by suppliers and external design partners has to be reviewed, converted, and integrated, because in some cases partners work with different systems. But here too, TS’s technology specialists are working on solutions.

On the basis of 3D data from the development team, production preparation experts can plan and simulate manufacturing and assembly processes by, for example, visualizing different assembly sequences The production units, in turn, use the 3D data as a basis for various work steps.

Despite the comprehensive use of 3D data in all units, 2D drawings are still required in the production and assembly areas. That’s because in some cases the drawings contain information that is too complex to be incorporated into 3D models without a great deal of time and effort. According to Belker, "we’ve proved that in principle we can do without the 2D drawings. However, there’s still no IT tool that effectively supports this process. We’re now working on reducing the time and effort required to create the 3D models."

Animated assemblies make it easier for workers to do their jobs, "because they can intuitively understand them much faster than 2D drawings with their countless positioning numbers," says Olbrich. The 3D data serve as virtual assembly instructions. Assembly workers are provided with a rapid overview of the entire situation, as well as more precise information about how to integrate the components to be assembled. It takes less time to learn the assembly steps, fewer questions are necessary, and there are fewer errors.

The 3D data are also very valuable for product descriptions and maintenance instructions at the end of the process chain. But 2D drawings are used here as well, first because 2D vehicle documentation is customary, and second because as yet there is no recognized format that makes long-term implementation of 3D data possible. However, one of the priorities at TS is to convince everyone involved of the advantages of 3D vehicle documentation.

Taken together, TS’s system allows the entire process chain to be depicted in virtual form. "Our customers are impressed by the way we’ve integrated these innovative technologies into our development processes," says Belker. Andy Neuschulz from trans regio Deutsche Regionalbahn GmbH agrees. "Virtual product development makes the production process easier to retrace and monitor. As a result, at an initial vehicle presentation we were able to offer visiting politicians a fairly realistic and very impressive picture of our trains at a very early stage of production," he says.

Currently, trans regio operates 20 trains running on three lines in Germany. After its next change of train schedules, it will begin to operate along the route from Cologne to Mainz via Koblenz, for which it will use a total of 16 Desiro ML trains manufactured by Siemens. Back in Krefeld, Reinhard Belker walks through the TS production hall, past rows of railroad cars draped with cables. Everything in the hall is clean and tidy. "Now that we’ve mastered virtual product and production development," he says, "the next step is what we call the digital factory. We’ve been rolling it out since last April." Plans call for TS to be ready by the end of 2009.

Simulating Entire Life Cycles. The digital factory is a concept of a production facility in which not only the physical plant is visualized and simulated on a computer, but also its processes. The concept includes the entire product lifecycle, from planning, development and production to service, maintenance, sales and marketing.

TS’s goal is to integrate development and production even more closely, make cooperation even more efficient, and align even larger portions of product and process development along parallel paths. The digital factory is an ideal way to coordinate process and layout planning and capacity analyzes. Here, all planners have access to the same database as the basis of their work. That enables them to significantly reduce errors and associated costs in production startup processes, as well as the time required for coordination.

Unlike the automotive sector, which has embraced the digital factory concept, other industries have generally avoided it because of their low production volumes, which did not seem to justify the large investments that are needed to realistically simulate processes. But in this sector in particular, comprehensive simulation of a product’s life cycle is crucial. This point is made very clearly by Dr. Robert Neuhauser, Director of Manufacturing & SCM at Corporate Supply Chain and Procurement at Siemens, who heads a company-wide program on the future of manufacturing. "For products that are manufactured in large numbers over a period of years, we can steadily improve and optimize production processes over long periods of time. By contrast, the project and small-batch business is characterized by short startup times and short manufacturing runs. That means everything has to work optimally the first time around, because the manufacturing process will be over before any significant optimization can take place. Simulation makes it possible to run through all the possible optimization measures digitally before production. That way, we can detect problems long before they reach the real world."

Simulation also benefits the Krefeld plant, which produces an average of 450 rail vehicles per year. A preliminary study and an efficiency analysis carried out by Siemens Transportation Systems in cooperation with the Fraunhofer Institute for Manufacturing Engineering and Automation (IPA) demonstrated the advantages of the digital factory. Its potential benefits include faster and better-quality planning. Integrated tools relieve planners of routine activities and give them more time to plan less expensive and qualitatively more sophisticated products and to make their production as cost-effective as possible from the very start.

Belker is looking forward to the advent of the digital factory. Surveying a long row of gleaming trains that are ready for shipment, he predicts that, "In the future we’ll be able to deliver them to our customers even faster."
                                                                                                                  Gitta Rohling