In Pursuit of Sensibility
Mercedes-Benz Embraces Today's Value-Conscious Consumer with an Assist from SL
Germany's preeminent car maker blends sensibility with stereolithography (SL) to squeeze time and cost out of product development cycles for its new class of cars. The technology has helped Mercedes-Benz to capture a cost savings of up to 80 percent over traditional prototyping, shrink product development time by a factor of anywhere from 3 to 20, and satisfy a critical shift in consumer preference.
One Sunday night in Stuttgart, an attentive Mercedes-Benz employee sat comfortably absorbed in "The Knoff Hoff Show," a popular German television talk show that reports on new innovations in technology. He was intrigued by the demonstration of a process used to produce three-dimensional plastic prototypes directly from CAD data on a Stereolithography Apparatus (SLA). What he learned that night would have meaningful impact on his company's future.
Three days later Mercedes-Benz contacted 3D Systems, pioneers of SL. Moving with the swiftness of their legendary vehicles, Mercedes-Benz decided to benchmark SL's part-building prowess. Nothing short of perfection would prove its bottom line value to the company's tough-minded engineers.
Benchmarks for Success
Under the watchful eyes of Manufacturing Engineering, led by Arnold Zieger, head of CAD, Berthold Mueller, workshop manager, and Juergen Weber, SLA specialist, an advanced design for an exhaust manifold was built in SL. In a very short time, the complex manifold emerged the model of perfection, giving the team the green light it needed. "The manifold design was ideally suited to SL," said Mr. Zieger. "In fact, you can't do it any other way and achieve such excellent design verification from three-dimensional CAD data."
With benchmark results as stellar as Mercedes-Benz's three-pointed star, the renowned automaker acquired two SLA 250s without hesitation. And a host of practical applications quickly became apparent. The SL exhaust manifold joined the all-new OM604 engine, which offers drivers higher power with lower fuel consumption. Unveiled in Germany in June of 1994, the OM604 is the first four-valve diesel engine in the world.
But then Mercedes-Benz is a company of firsts, having amassed over 10,000 patents in its rich history. Nowhere is this legacy more apparent than in Manufacturing Engineering, the pivotal technical link between the designer, the drawing board and the production line. Painstakingly, the group ferrets out pragmatic solutions to reduce engineering costs and shorten product development cycles - always with the goal to further Mercedes-Benz's exacting standards for design, performance and safety integrity.
Demand Brisk - SLA 500 Added
Manufacturing Engineering relies heavily on SL to develop critical components for the company's compact, executive and luxury-class cars. Over 500 parts are now built on the SLA 250s each year. Earlier this year, Mercedes-Benz expanded its SLA family by adding the higher throughput SLA 500, suitable for building larger parts, to satisfy brisk demand for SL services. With the additional SLA, production activity is soon expected to reach 1,000 SLA parts annually.
SL has consistently "made the difference" for Mercedes-Benz in achieving greater efficiency. When the company changed from two to four valve engines last year with the new M111, a new cylinder head cover had to be developed. SL made it no only practical, but possible to prove the concept and meet all product development schedules with time to spare. What's more, 50 SL parts for five different M111 engine versions were built resulting in a savings of DM180,000 over conventional prototyping methods.
Bottom Line Benefits
Using the exhaust manifold as a barometer, the company calculates that SL results in "a cost savings of up to 80 percent and a time savings of a factor of anywhere from 3 to 20 over conventional methods to produce first models, gains consistently reached regardless of part geometries," declares Mr. Weber.
Notwithstanding savings, SL also plays an important role in the company's relentless pursuit of design innovation and product quality.
Ever since Gottlieb Daimler and Karl Benz joined forces to invent the first automobile in 1886, Mercedes-Benz has been known for reliability, durability and safety engineering. For that reason, the capability to perform multiple part iterations on new designs and test out concepts accurately makes SL an investigative and problem-solving tool of immeasurable value to the company.
At one point the Development Department was puzzled why they couldn't find an internal oil leak on a new engine design. So they built a full-scale intake manifold in SL and ran it on an actual test bed. In doing so, they were able to visually pinpoint the unwelcomed leak and eliminate it.
Company engineers also communicate more easily in the three-dimensional language of SL to visualize and verify their designs. Using SL in concurrent engineering, multi-functional teams can leap from an abstract idea to physical hardware in weeks instead of months. Moreover, they find design flaws faster before commitments to expensive production tooling.
Masters for Tooling
When experimental or pre-production parts are required, Mercedes-Benz uses SLA built parts to create masters for soft tooling, depending on part complexity. On requirements up to 500 parts, absolutely no hard tooling is necessary, thus bypassing the potential for a costly six-figure investment.
Mercedes-Benz is pushing the technical envelope once again. Recently it added QuickCast to its manufacturing arsenal. 3D Systems' latest advance, QuickCast provides a unique build style for high strength epoxy resins that enables manufacturers to move from design to metal parts in record time. The Stuttgart team has already built dozens of QuickCast parts with far-reaching implications. "If [QuickCast] keeps doing as well as in our early tests," maintains Mr. Zieger, "it will open up a whole new way in manufacturing engineering and in pre-mass production for the automotive industry."
The Virtue of Value
Leadership in automotive technology carries a hefty price tag. In a decade when consumer preferences shifted from luxury to affordability, Mercedes-Benz has responded with Cheetah-like speed to launch a full line of "value-priced" vehicles. The E Class (executive) cars have been refined to offer a seamless blend of style, function and value. And its new C Class (compact) line of luxury cars promises to impress the most discriminating car enthusiasts.
In part, Mercedes-Benz's ability to respond to market demands for value-pricing comes from trimming of production costs and improved productivity. Many agree, however, that such processes as stereolithography for rapid prototyping add a high octane advantage to their engine of progress. As Mr. Zieger points out, "SL has played an important role in helping Mercedes-Benz trim production costs to support the introduction of our value-priced class of cars."