Rethinking The Car And Manufacturing

OEMs are rethinking the automobile in terms of materials, propulsion systems and the supporting industrial infrastructure.

After Harley J. Earl brought styling to the attention of General Motors Corp. (and the rest of the industry) in 1927, concept cars displayed at auto shows became little more than celebrations of appearance. (For example at GM's, Earl's new styling department was originally named the Art and Color Section.) Today something more profound is happening. Concept cars, even new production models are emphasizing fundamental shifts in technology. Few industries are unaffected. Judging from the recent auto shows, art and color are increasingly subordinated to exciting conceptual innovations that permeate every element of prototypes and new vehicle design and manufacturing. (That may explain why suppliers and would-be suppliers are increasingly crowding other viewers at auto shows, quips one analyst.) Driven by new visions that rethink the entire automotive experience, carmakers are challenging the supporting industrial infrastructure. Innovations in vehicle materials and propulsion systems are revising vehicle production methods. Industry insiders at last September's fifth Global Powertrain Congress focused on the upcoming changes. Their consensus: The next 10 years are likely to see more profound changes in the automobile industry than have occurred in the last 50. They concluded that many of the changes will be driven, literally and metaphorically, by the powertrain. For example, hybrid propulsion systems are beginning to be marketed by Toyota and Honda, and industry research is focusing on fuel cells. At Detroit's North American International Auto Show last month, GM announced it would offer some version of hybrid electric power on five models by 2007. Astute members of the supplier community (and the wannabes), of course, are doing more than attending shows and conferences. They're partnering with OEMs to sustain or gain supplier status with the new technology. A startling example of a new direction is GM's AUTOnomy concept, which has the potential of rethinking not only the car, but quite possibly GM and the industry itself, say some analysts. The concept unites fuel cell propulsion and drive-by-wire systems with a unique "skateboard" chassis that quickly and easily accepts new bodies. What's more, the concept substitutes new components, system modules and materials. The proposed design has no need for an internal-combustion engine, drivetrain, transmission, mechanical and hydraulic linkages or axles. Assembly plants and equipment will be dramatically different, too. In North America, GM's idea first surfaced at the January 2002 North American International Auto Show in Detroit. Then in a record eight months GM unveiled a fully functional prototype labeled the Hy-wire at the Paris Auto Show. At the show Larry Burns, GM's vice president of research, development and planning announced: "We are driving to have compelling and affordable fuel cell vehicles on the road by the end of the decade. With Hy-wire, we have taken the technology as it exists today and packaged it into an innovative and derivable vehicle comparable in size and weight to today's luxury automobiles." To GM, customers and suppliers alike, Hy-wire has stunning implications. Some big challenges remain: Will fuel cell technology and a vehicle refueling infrastructure issues enable GM's 2010 objective? The concept's potential for reducing the cost of building automobiles provides compelling encouragement. The by-wire features alone have substantial potential for lowering vehicle assembly costs, says Phil Cunningham, director, product planning for chassis products, TRW Automotive, Livonia, Mich. He notes that by-wire braking systems give vehicle assemblers more opportunity to treat braking systems as a plug-and-play module. "Instead of 'piping up' a braking system and then filling it with hydraulic fluid, vehicle assemblers could simply plug in a pre-assembled by-wire module," adds Cunningham. "Another enticement is the ability to achieve desired vehicle dynamics via a simple software programming step." Conceptually, Hy-wire adds design and manufacturing flexibility by expanding on the body-on-frame idea now only commonly found on pick-up trucks and sport utility vehicles. With all the propulsion components -- fuel cells, hydrogen tanks and electric motor -- housed in the aluminum skateboard, there is neither a hood nor a conventional internal combustion engine interrupting passenger space. Keeping the drive train separate from the passenger compartment offers unique design freedom. Bodies can be designed to be easily swapped -- in minutes. Conceivably an owner could have a minivan body for weekdays and a convertible for weekends -- all using the same skateboard. Will the concept reshape GM into being primarily a skateboard provider? Will a dominant skateboard maker evolve in the competitive fashion of a Microsoft? Does this signal the creative destruction of the GM business model we know? In addition to disrupting today's supply chains for conventional parts, system modules and materials, the Hy-wire could open up the possibility of owners being enticed by non-GM bodies in a developing aftermarket. GM's design intent is to produce skateboards with a 10- to 20-year useful life, observes automotive consultant James V. Gillette, vice president, IRN Inc., Detroit. Will customers begin buying new bodies as casually as they buy new cars today? Conceptually Hy-wire would expose the car buyer to the economical possibility of repeatedly rebodying an existing chassis. In the 1920s, wealthy customers bored with a custom-bodied chassis would often send it off to be rebodied. With the Hy-wire, rebodying would take minutes while a custom body shop might require months. Cost of replacement would be lower, too. The key to the easy body swaps is GM's full exploitation of the auto industry's emerging "drive-by-wire" trend. Instead of using cables, hydraulics, and mechanical linkages for functions such as steering, braking and accelerator control, the Hy-wire substitutes electronic actuation. "At the heart of the by-wire system are smart electro-mechanical actuating units, which convert the driver's commands from electronic signals to motion," says Tom Johnstone, president of Sweden-based SKF's Automotive Division, GM's by-wire technology partner. The by-wire technology idea, borrowed from advanced aircraft, facilitates body swaps by making drivetrain connections a simple plug-and-play consideration, says Mohsen Shabana, chief engineer for the Hy-wire program. Hy-wire uses a single docking connection. Shabana is part of GM's Design and Technology Fusion Group at the Technical Center in Warren, Mich. The advantages of by-wire technology also have disruptive potential in product sectors other than cars or airplanes. For example, SKF unveiled a by-wire intensive forklift prototype, the E-truck/HFO, at last year's Hannover Fair. The claimed benefits range from assembly advantages for truck makers to performance gains for users. SKF cites benefits in maintenance, part count, energy efficiency and functionality. The advantages of by-wire technology in automobile applications go beyond the elimination of steering columns, pedals and mechanical and hydraulic linkages. By using on-board computers, driving and handling characteristics can be programmed via software, adds Shabana. The software can quickly make handling appropriate for any body fitted to the skateboard. Imagine a car that like a computer can accept upgrades via software. The convergence of computers and by-wire technology is emerging in the latest vehicle announcements. For Example, Ford Motor Co. announced that the accelerator pedal on the 2004 Explorer is connected to the engine via an electronic by-wire system. Also, the rear braking system on the 2003 Mercedes-Benz S-Class luxury sedan incorporates by-wire actuation with a hydraulic back-up. In future models the by-wire braking system might play a role in the Mercedes-Benz Pre-Safe occupant protection system. Today's Pre-Safe system uses electronic sensors and actuators to sense a possible collision a few seconds in advance and take pre-crash protective measures. Able to sense an imminent crash up to five full seconds before the actual impact, the Pre-Safe system is able to do such things as tension seat belts, move seats to their safest position and close an open sun-roof. Pre-Safe reacts to uncorrected fishtailing (or oversteer) as well as "plowing" (or understeer). In future model years, the Pre-Safe feature may be designed to interact with a vehicle's by-wire systems to enhance occupant safety. Today's Pre-Safe focuses on monitoring the brakes to detect emergencies. The Material Difference GM's Hy-wire, noteworthy for its totality of change, is not the only bellwether of what will be made and how it will be made. Other vehicles now on the auto show circuit also display compelling evidence of directions that will reshape the rest of industry. Aluminum-bodied vehicles continue to make disruptive inroads, says Don Runkle, vice chairman and chief technology officer, Delphi Corp., Troy, Mich. "The use of aluminum has implications for the process -- assembly and painting methods and equipment, stamping, dies -- as well as for the design of vehicle components. Dealer service organizations also have to be prepared." One example is the debut of the 2004 Jaguar XJ at September's Paris auto show. (U.S. availability: mid-2003) Representing the seventh-generation of the XJ, the saloon is more than a roomier iteration (four inches longer, four inches wider and five inches taller) of a sedan introduced 34 years earlier (to the day!). Although undetectable to the casual observer, the new XJ has shed 440 pounds as a result of an aluminum unibody, the first in the Ford stable. The result, says Jaguar, is improved performance in terms of livelier acceleration, better handling and improved ride and occupant comfort. "We chose a lightweight aluminum vehicle architecture for the new XJ not because it was something new, but because it enabled us to deliver real and significant benefits to our customers," says Jaguar's David Scholes, chief program engineer. The XJ is even lighter than Jaguar's smaller S-type sedans. By partnering with Alcan Inc., Jaguar engineers were able to design a stamped aluminum sheet structure that is 40% lighter than conventional steel materials and 60% stiffer than the predecessor model. The added rigidity derives from bonding the structural sheet sections with self-piercing rivets and an epoxy adhesive, explains Alcan Automotive's Mike Kelly, vice president and global program director for the Ford portfolio. Virtually no welds are used in constructing the stamped aluminum sheet unibody, says Jaguar. Kelly notes that some competitors, such as Audi, use a space frame body structure that combines extrusions and hydroformed parts with castings that join them at the corners. Kelly claims two advantages for the sheet aluminum unibody approach -- suitability for high-volume production and process familiarity. "The approach eases implementation. It matches the current automotive culture of [using] sheet steel. To a car manufacturing guy stamping and assembly [processes] look pretty much the same." Jaguar assembles the XJ at its Castle Bromwich plant, a U.K. facility that once made fighter planes. Also debuting in 2003 as a 2004 model is Audi's second-generation iteration of its aluminum A8 luxury sedan. First introduced in 1994, the new aluminum bodied A8 features a fully enclosed space frame with 60% higher rigidity than its predecessor. Audi partnered with Alcoa to facilitate space frame development. Audi claims to have sold more than 170,000 cars made of aluminum. Instead of riveting, the new model uses a laser-hybrid welding process to join large aluminum panels. Each A8 has over 65 feet of laser welded seams, says Audi. Is aluminum just for luxury vehicles? The emergence of the XJ and the A8 as aluminum vehicles would seem to suggest that little has changed since the Peerless Motor Car Co. prototyped an all-aluminum V-16 limousine in 1932. (It was the dying gasp of the last Cleveland-based automaker that in 1934 switched to doing business as the U.S. brewer of Carling's beer and ale.) In 1999, Audi answered the question with its aluminum-bodied A2, a small car that competes in the same market space as the Mercedes-Benz A-Class and the VW Golf. Meanwhile significant wins have occurred in vehicles predominantly made of ferrous materials. For example, the GM family of full-size SUVs (Yukon, Tahoe, Suburban and Escalade) now offers a lightweight aluminum liftgate that is easy to open and close. Since 1991 applications in cars have doubled and even tripled in sport utility vehicles, says the Aluminum Association Inc., Washington, D.C. Components such as engines, suspension components and hoods and fenders are typical. "From where I sit, the [all] aluminum vehicles we have at the moment are all about niche or brand, says automotive engineering consultant Jeremy W. Holt, president, Ricardo Inc., Van Buren Twp, Mich., the North American unit of Ricardo plc, Shoreham-by-Sea, West Sussex, England. "They're less about 'this is the direction we're going to go because it's the [only] logical way to reduce cost or improve performance or anything else.'" The competition between aluminum and steel is making both camps so responsive to user needs that application success depends more and more on users being up to date on the rapidly evolving technology, observes analyst Mike Wall, IRN's director of forecasting. One example is the significant new attributes offered by advanced high-strength steels (AHSS). A study by the American Iron and Steel Institute (AISI) shows a superior combination of high strength, crash energy management, excellent formability and dent resistance at no additional cost. The principle difference between AHSS and conventional high-strength steels is in their microstructure. Conventional high-strength steel is formed by adding certain alloys to the microstructure, whereas AHSS is formed by controlling the cooling rate of the steel. AISI says the new material can be applied at thinner gauges than conventional steels for reduced overall vehicle mass while actually improving component strength and maintaining crash performance. Anticipation of the North American potential for diesel engines is another significant manufacturing change agent. In Europe, diesel engines form about 50% of the installed base, explains Roger W. Cope Vice President, business development, UNOVA's Lamb-Cincinnati Machine, Warren, Mich. The company is observing diesel's growth in Europe -- about 20% per year -- and anticipates a similar pattern in North America. Cope is optimistic that today's diesel performance will even win over those who were disappointed with the last wave of U.S.-made diesel automobiles. Cope's target: a market needing tooling, fixturing and machine tools designed to cope with the new high performance diesel engine materials. A recent win is a new manufacturing line being delivered to a European plant of Ford Motor Co. The line is designed to contend with a high performance material called compacted graphite iron (CGI). Stronger, stiffer and lighter than traditional cast iron, CGI is also more difficult to machine, adds Cope. "CGI impacts the capital equipment selection process," he concludes.

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