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More than a pretty fascia

More than a pretty fascia

DaimlerChrysler's new PT Cruiser, due in a showroom near you in March 2000, could well be the prototype for future concept cars.

Introduced at the Geneva Auto Show in March 1998, it joins a short-but-distinguished list of "dream cars"the Viper, Prowler, Neon, Intrepid, Cirrus, and Stratusto actually get produced.

Amazingly, it's time from conception to birth will be a mere 24 months.

"Today, the thesis statements for our concept cars are much more rooted in reality," notes Tom Gale, executive vice president of product strategy, design, and passenger car operations for DaimlerChrysler. "It's not to say that dream cars aren't appropriate. But the ones that resonate with customers are the ones that have a thesis that's current." As an example, Gale points to the Dodge Viper. Some potential customers were so moved by the sight of the Viper concept cars that they sent blank checks to Chrysler Corp.

The ability to create such resonant designs is due to the availability of new technology. Today, designers and engineers can afford to focus on current themes because technology enables them to bring a vehicle to market in 24 months. That's a far cry from the way it was a decade ago. Back then, designers scanned the far horizon in search of customer trends that might exist five to seven years down the road. As a result, their concepts were often too far afield to reach fruition.

No more, though. Digital techniques have revolutionized vehicle design and now they're taking the concept car along for the ride. On the PT Cruiser, DaimlerChrysler designers and engineers used all manner of digital aids, from Digital Modeling Assembly (DMA) to virtual reality. Those aids enabled them to see and "experience" concepts. "It allowed us to evaluate thousands of prototype designs," notes Mike Donoughe, director of small car platform program management for DaimlerChrysler. "If we hadn't had this, we would have looked at between two and five prototypes. That's how much of a difference digital modeling made."

From the earliest stages of the PT Cruiser program, DaimlerChrysler used IBM/Dassault's CATIA CAD package to link internal design, engineering, and manufacturing departments, as well as outside vendors. CATIA and DMA enabled them to assemble components in three dimensions before building actual physical prototypes. By doing so, they were able to check fit and finish of components. Using virtual reality, they experienced the PT Cruiser from the perspective of the occupants, which helped them optimize the interior and its ergonomics. Incredibly, much of that activity occurred during the design of the concept vehicle.

Working this way also enabled DaimlerChrysler to check on the technical feasibility of the design. Metal stamping, for example, has traditionally been a problem area for concept cars. Because the vehicles are designed to look futuristic, sheet metal often takes on shapes that can't be easily manufactured. But by applying metal stamping software to digital shapes, engineers could check the feasibility of the PT Cruiser's sheet metal. That way they could easily make decisions about whether they wanted to compromise the look of the vehicle, or change the manufacturing process to accommodate the desired shapes. Those decisions were made within weeks of launching the program.

New timetable. That, of course, contrasts sharply with the traditional methods used in concept car programs. In the past, concept cars started as sketches and renderings. Those were followed by clay models, which were built by sculptors in the design departments. Unfortunately, the process of building clay models was a long and tedious one, during which designers rarely talked with engineers. "It took about eight months for a clay model to come together," notes Ed Welburn, director of GM's Corporate Brand Character Center. "And we couldn't really get useful information until the clay model was finished and we had an entire surface to work with."

Today, however, concept car designers can begin their dialogue with engineering and manufacturing earlier because the shapes are available in a mathematical format. The reason: Concept sketches are now done on computers -- GM typically uses Alias Wavefront software for the sketches. Designers also digitize clay models using a device akin to a three-dimensional scanner, which takes a physical shape and turns it into mathematical data that can be used by engineers.

Using either method, automakers have found novel ways to view and experience the data. GM, for example, has its own Virtual Reality Center in which engineers can view the renderings on so-called "power walls." Wearing special glasses, they see the sketches in three dimensions. The VR Center has three projection screens, so participants can compare digital models to competing vehicles shown on the other screens.

GM's VR Center also houses a facility known as "The Cave," which enables designers and engineers to view a vehicle's interior. In The Cave, users wear glasses that are wired into the vehicles. "You know that it's not a real interior, but you begin to feel comfortable in it," Welburn says. "I find myself trying to put my elbow on the armrest, but it's not really there."

The Cave lets users to do more than merely "see" their interior -- it allows them to experience it. They can check such parameters as available space, downward vision, and physical obstructions. "To do the same thing in clay and plastic would be terribly difficult and time consuming," Welburn says. The Virtual Reality lab has proven so useful that GM designers and engineers now must make reservations it weeks in advance to use it.

GM has also employed the VR Center for redesigns, as well as for changes on existing products. Using math-based techniques, designers and engineers recently worked together to develop a new rear access door for Saturn's three-door coupe. Virtual reality enabled them to "see" the new door line for the vehicle, as well as make all the necessary interior changes. As a result, they cut the redesign work by months, Welburn says. GM is also said to be using the same techniques to bring the Pontiac Aztek into production.

Flights of fancy. Despite the new emphasis on reality, automakers say that the creativity of the concept car process hasn't suffered. "If we want to do something way out -- a car with wings or a car that travels through water -- we can still do it," Gale says. "But there has to be a good reason for doing it. And it must be current."

Indeed, the PT Cruiser proves that DaimlerChrysler hasn't lost its willingness to take risks. The vehicle, which looks like a cross between a VW Beetle and a minivan, is unlike any production vehicle that's gone before it. It combines a high roof line and high belt line with exaggerated fenders and simulated flared side sills, giving it the look of a 1940s taxicab.

Creativity, however, isn't the only benefit of the new concept car process. Engineers report that it also fosters a contagious form of enthusiasm. "It's like the introduction of a hot new stock," Donoughe says. "Everyone gets enthused and then they want to be part of the program. That's what happened with the Viper."

Equally important, the process has a direct effect on the bottom line. Products come to market more quickly. And engineers say they make fewer mistakes. As a result, programs stay on course more often. And product managers are forced to make fewer long term prognostications, since cycle times are compressed to half of what they once were.

Most importantly, automotive engineers say that the new principles are applicable to any design situation. "These techniques are not unique to the automotive industry," Donoughe says. "You could apply them to the design of a tube of toothpaste or a piece of construction equipment."

The key, engineers say, is a willingness to accept a new methodology. "There are a lot of cultural issues that need to be addressed," Donoughe says. "But the thread that binds it all together is technology. Computer technology is growing by leaps and bounds, and you need to be willing to take advantage of that."


The PT Cruiser: 24 months from concept to production

In the world of concept cars, any vehicle that makes it to the showroom floor is unusual. But one that goes from concept to production in 24 months is a true rarity.

PT CRUISER SPECIFICATIONS
Overall length 168.8 inches
Overall width 67.1 inches
Overall height 63.0 inches
Wheelbase 103.0 inches
Interior volume (EPA) 119.8 cubic feet
Cargo volume (EPA) 18.3 cubic feet

That, however, is exactly what the PT Cruiser did. Introduced at the Geneva Auto Show in March, 1998, it is now slated for a March, 2000 market launch.

And true to its concept car roots, the PT Cruiser is unlike any vehicle that's gone before it. Its high roof line belies its stubbiness, the vehicle is actually shorter than a Dodge Neon. Yet it has interior volume (119.8 cubic feet) almost equal to that of a short wheelbase minivan (122 cubic feet).

The theme of the vehicle is practicality -- the "PT" in the name stands for "Personal Transportation." And it is designed for virtually any use, ranging from hauling cargo to staging tailgate parties. Its rear seat can be folded or removed and the front seat can be configured to form a tabletop. Manufacturer's information says that the interior of the vehicle is long enough to hold an eight-foot ladder.

DaimlerChrysler engineers say they considered thousands of digital prototypes before settling on the current design. "The digital process is what allowed us to harmonize the interior and exterior of this vehicle," says Mike Donoughe, director of small car platform program management for DaimlerChrysler. "We couldn't have brought this vehicle to market so fast without it."

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