PLM: 3D Process Simulation Delivers

Market demands require manufacturers to bring products to market faster than ever, even though the products themselves have become more complex. This puts pressure on machine builders and manufacturers. They must work faster to create new, more flexible equipment while continuing to meet customers’ cost and quality requirements.

By Control Engineering Staff September 1, 2008

Sidebars: SEAT sees tangible benefits of simulation

Market demands require manufacturers to bring products to market faster than ever, even though the products themselves have become more complex. This puts pressure on machine builders and manufacturers. They must work faster to create new, more flexible equipment while continuing to meet customers’ cost and quality requirements. Product lifecycle management (PLM) software provides a tool—3D process simulation—that can help alleviate the pressure.

A case in point

Symax Systemtechnik Sondermaschinenbau GmbH is well aware of these challenges. Its 100+ employees develop and manufacture machines and systems that automate production and assembly processes. The company also produces test systems, hydraulic systems, and material handling equipment.

Based in Neutraubling, Germany, Symax handles everything from concept planning to the development and manufacturing of customized solutions; its equipment can be found in Europe, the U.S., Japan, China, and Mexico. In 2004 and 2005, the Bavarian Ministry of Economics honored Symax as one of the “Bavarian Top 50” for its clear commitment to innovation and expansion.

Approximately 40% of Symax’s projects involve robots.

“As our processes are becoming more complex, we often face questions at the beginning of the planning phase about whether a robot will work under the given circumstances,” explains Robert Lehner, managing director at Symax. “We needed a simple tool that we could use to virtually evaluate our production concepts over the entire lifecycle of the new product, including production ramp up.”

The company found its current solution in the Tecnomatix Process Designer and Process Simulate software packages from Siemens PLM Software. Process Designer is the planning and process authoring environment of Tecnomatix, based on the eMServer (a multi-tier distributed architecture that supports distributed and collaborative IT/manufacturing environments). Process Simulate is the simulation environment for kinematic 3D simulations, like those required to validate robots. Ergonomic studies can be performed in Process Simulate using a human model.

Simulation software provides Symax:

The ability to visualize robot operations in a 3D environment;

Early feedback about idea feasibility;

Simulation videos that can be used for presentations instead of drawings; and

Offline programming and validation of controls and processes.

Database of models

Process Simulate is based on the eMServer as well and therefore reads and writes the same data as Process Designer. The software’s user interface corresponds to the Microsoft Windows standard, incorporating familiar icons, tabs and established navigation practices. Data can therefore be transferred to office solutions and, at Symax, Process Simulate connects to an Oracle database that manages all component data.

To setup a simulation, robot motion is programmed using kinematic sequences imported from related databases. Symax performs this step using Process Simulate—Robotics, which is a multi-user robotics solution that also exchanges data with Process Simulate.

After robot motion is programmed and imported, product data in the form of 3D models and floor plans are also imported. The robot tracks and assembly lines are virtually generated. Building the libraries of models and sequences takes time upfront but, once they are built, the database structure allows them to be quickly found, reused, and modified as needed.

Simulation allows engineers to determine whether the space allotted for a process is sufficient for the prospective solution. They can also see, in real time, whether the production process can run safely according to the specified motion paths and workstation times, and can also determine whether there are any collisions among moving parts.

Typically the engineers run a variety of scenarios, such as replacing three big robots with four smaller ones, to evaluate alternative solutions. Simulation helps Symax understand, as early as possible in the planning phase, the behavior of assembly processes, manual and tool operations, equipment, and robots. They can also synchronize areas with more than one robot.

This understanding allows engineers to optimize the equipment and have the assurance that complex processes will work perfectly—even before the initial operation. With potential manufacturing problems recognized at an early stage, this information can be transmitted to product development, significantly reducing cost of changes and improvements.

One type of project where simulation plays an important role at Symax is in the development of a robot-assisted assembly process. In this case, a robot acts in cooperation with a human worker, rather than alone within an enclosed cell. Although the regulations regarding this type of robot have just been defined in Germany, Symax already has the first order for this type of solution, and the use of simulation software helped them get it.

Symax engineers created a simulation that shows the detailed manufacturing process: A robot automatically fetches a roof module from a conveyor belt and takes it to the activity area of the worker who does the final installation. The worker can control the movements of the robot using a joystick. To ensure the worker’s safety, an absolutely reliable depiction of the direction and velocity of the robot movement was necessary.

Using the simulation software Symax clearly showed that the robot moves at a slower speed within the hazard zone than outside of it. Moreover, the simulation of the manual steps shows the worker’s field of view and posture, and allows for analysis of ergonomic factors.

When communicating with potential clients, Symax can export a simulation scenario as a video in .avi format and show it in a presentation at their facilities. The video can be shown in real time, or step-by-step in slow motion to show every procedure. A 360-degree rotation gives an overview of the whole facility. Zoom tools allow observations from different points of view, such as from a wide angle to a detailed view.

An animated demonstration conveys the basic concepts of a production process in just a few minutes, without the need for extensive technical drawings. In a short video sequence of three or four minutes, engineers at Symax can show the fully automated installation of rubber gaskets onto car bodies, or the handling of front axles during installation on a moving assembly line.

“By digitally showing that our solution works, we have a good possibility of winning the sale,” says Christian Ruhland, project manager at Symax. “Typically we present complex robot solutions that neither our clients nor our competitors have considered. By showing 3D simulations to the client in planning meetings, we show them in detail what we have developed.”

Symax is also collaborating with the Department of Production and Automation Engineering at the University of Applied Sciences in Regensburg, Germany, to assist in student research projects using 3D simulation, while Symax Symax engineers use it everyday. “Using this tool gives us time to investigate innovative ideas while proving from the very beginning that they can be realized trouble-free,” says Lehner.

SEAT sees tangible benefits of simulation

Simulation is an important aspect of digital manufacturing, the overall goal of which is to reduce development time for new manufacturing lines. As such, manufacturers, machine builders and system integrators of all sizes can benefit from the efficiencies to be gained from digital manufacturing.

Although it operates in more than 70 countries from its headquarters in Barcelona, Spain, SEAT (a Spanish subsidiary of Volkswagen) is considered relatively small in the world of automotive manufacturing.

“When it comes to producing a new car, response times and delivery deadlines are much more important to SEAT than they would be to a large company, so we have to move quickly,” explains Manfredo Keuthe, SEAT’s assembly and paint processes manager. “We achieve this by using digital manufacturing computer-based simulation, which results in development time reduction.”

The Spanish automotive manufacturer decided in 2004 to accelerate the path toward digitalization of its manufacturing processes. It started the project with its new SEAT Leon, a car model in the middle of its development. A long-time Robcad robotics programming software customer, SEAT chose Siemens PLM Software’s Tecnomatix digital manufacturing software solution. Process Designer, Siemens’ manufacturing process management and analysis tool, serves as the project’s platform and database. SEAT also uses Siemens PLM Software’s Plant Simulation.

“Many automotive companies have started to apply digital manufacturing in a specific areas such as press stamping or panel welding,” says Keuthe. “We’ve started to implement an integrated manufacturing planning management system. This makes it quite an exceptional case within the automotive industry, far from the ambitious digital manufacturing projects of the major manufacturers. SEAT is using modern IT tools, but always with a very Spartan approach that allows for investments to be translated into tangible improvements.”

“We can’t allow ourselves the luxury of paying for showy digital manufacturing IT solutions,” Keuthe adds. “Instead we looked for digital manufacturing tools that would give us visible returns.”

Those returns have included:

First phase of physical prototyping has been eliminated;

Second phase is more cost-efficient and reliable;

20% reduction in time to market;

Faster access to information; and

More highly motivated personnel.

Keuthe says an important factor for SEAT was choosing tools that were “as standard and pre-tested as possible, which is something that many large automobile companies don’t take into account because they have the capacity to create a tool tailor-made to their needs. We don’t have a large development capability so the use of packages with customizable user interfaces that are interoperable with other IT packages is an ideal solution for SEAT. They allow us to combine the flexibility of the latest systems with the experience of a company that has a great deal of knowledge of the industry’s needs.”

The current project is a collaboration among Siemens PLM Software, SEAT, and Gedas consultants, who are integrating the PLM software at SEAT.

Keuthe points out that employee incentive also is a factor in SEAT’s success: “We’ve managed to motivate people by providing faster and more powerful tools. At the beginning, workers were reluctant to accept change, but when they saw everything they could do with the new tools, they became enthusiastic.”