A new hybrid mousetrap?Building a better mousetrap "A Better Mousetrap" is a first season episode of Beast Wars which first aired on October 8, 1996. Plot Sentinel, a new automated defense system for the Axalon, is under development by Rhinox, as the Maximals' best line of defense against a Predacon attack. can be a daunting daunt tr.v. daunt·ed, daunt·ing, daunts To abate the courage of; discourage. See Synonyms at dismay. [Middle English daunten, from Old French danter, from Latin task, especially since the one on the market since 1897 already has a kill rate of 80%-plus, which in itself would seem impossible to surpass. With a success rate like that, why would anyone even consider trying to break the mold set by a proven process? Like James Henry James Henry is the name of:
The process of causing a body to move by exerting a force against it. Propulsion is based on the reaction principle, stated qualitatively in Newton's third law, that for every action there is an equal and opposite reaction. technology that it believes is the standard of the world and since the hybrid Prius debuted in Japan in 1997, the automotive world has been trying to keep up. Honda was the second out of the gate with its Insight, while others quickly followed. Still, Toyota was and is viewed as the world's hybrid leader--estimating it has saved consumers more than 135 million gallons of gasoline worldwide via its hybrid technology--but there are a few major automakers who think they may have developed a better hybrid mousetrap, one that will set them apart from the "traditional" hybrid players An optical device that supports more than one format. See Blu-ray and HD DVD. See also hybrid drive. . In 2004, General Motors and DaimlerChrysler announced a joint venture to develop a two-mode hybrid system A hybrid system is a dynamic system that exhibits both continuous and discrete dynamic behavior — a system that can both flow (described by a differential equation) and jump (described by a difference equation). that would reduce overall fuel consumption without sacrificing towing and power capabilities for light trucks, SUVs and vehicles with large engines. BMW BMW in full Bayerische Motoren Werke AG German automaker. Founded as an aircraft engine manufacturer in 1916, the company assumed the name Bayerische Motoren Werke and became known for its high-speed motorcycles in the 1920s. joined the team about a year later, hoping to take advantage of the anticipated volume savings to be generated by the partnership. With nearly three years of work under their belts, the partners are beginning to unveil the secrets of their technology, which will debut on the Chevrolet Tahoe The Chevrolet Tahoe (and similar GMC Yukon) is a full-size SUV from General Motors. Chevrolet and GMC sold two different-sized SUVs under their Blazer/Jimmy model names through the early 1990s. This situation changed when GMC rebadged the full-size Jimmy as the Yukon in 1992. in 2007, followed by the Dodge Durango The Dodge Durango is an SUV from Chrysler's Dodge brand. It debuted in the 1998 model year and was redesigned for 2004. It fills the gap in the Dodge lineup since the cancellation of the Dodge Ramcharger in 1993. in 2008. The technology is expected to migrate to the BMW soon after, along with rear-drive passenger car applications for Mercedes-Benz. [ILLUSTRATION OMITTED] [ILLUSTRATION OMITTED] What the partners have done is focus on the transmission as the conduit, devising a system that utilizes more mechanical power than electric power--since nearly 30% of the power produced via electrical means is lost in transfer to the driveshaft, while less than 10% of mechanical power is lost in the process--through the use of four planetary gear sets, two clutches and two 60-kw electric motors, all packaged in a unit the size of a traditional 6-speed automatic transmission. "There are four fixed gear ratios superimposed su·per·im·pose tr.v. su·per·im·posed, su·per·im·pos·ing, su·per·im·pos·es 1. To lay or place (something) on or over something else. 2. on two electric variable ratios," explains Larry Nitz, executive director of hybrid powertrain engineering at GM. "What are new are the four fixed gears. There are more mechanical parts and that allows us to make the electric motors half as big. When I look at some hybrids, the electric motors inside the transmission may be 1.3 times engine power and it may be almost 10 times the battery power and that tells me it is not an electrically efficient system." Since planetary gear sets can be easily mass produced and cost sufficiently less than larger electric motors and the various electrical components associated with them, the partners are comfortable they will be able to provide hybrid powertrains at less cost and reduced weight than traditional hybrid systems. It is unknown how much the two-mode system will boost overall fuel economy, although GM executives have hinted in the past the system could reduce fuel consumption by as much as 25%-30%, depending on the application and operating cycle Operating cycle The average time between the acquisition of materials or services and the final cash realization from that acquisition. operating cycle . Speaking of operating cycle, the two-mode system can be powered by either the two electric motors or by the combustion engine or both simultaneously during city and stop-and-go traffic conditions. The amount of power that must be transmitted electrically varies with the vehicle speed, determined by the ratios of the planetary gearing and the speeds of the motors. By adding another planetary gear set, along with two clutches, torque is boosted at lower speeds. When the first clutch is applied and the second clutch is open, the system operates as an input split electrically variable transmission. When the second clutch is applied and the first clutch is released, the system operates as a compound-split Electrically Variable Transmission (EVT EVT Eventueel (Danish: Maybe) EVT Extreme Value Theory (prediction tool for extrapolation of trend graphs) EVT Embedded Visual Tools EVT Emergency Vehicle Technician EVT Erstverkaufstag ) and the two-mode is able to shift between these two ranges in a synchronous Refers to events that are synchronized, or coordinated, in time. For example, the interval between transmitting A and B is the same as between B and C, and completing the current operation before the next one is started are considered synchronous operations. Contrast with asynchronous. manner, providing seamless toque transfer between the modes without any recognizable change to the operator, all while providing electrical regeneration to the batteries, which are constructed from nickel metal hydride (NiMH) A rechargeable battery technology that has approximately 30-50% more charge per pound than nickel cadmium. Introduced in the early 1990s, it uses nickel and metal hydride plates with potassium hydroxide as the electrolyte. . "When the power transfer happens the driver doesn't know it happens," Nitz says. To boost the capabilities of the hybrid system during trailering and highway operations, once the system reaches fourth gear power goes through all the gearing with one motor acting as the booster Booster - A data-parallel language. "The Booster Language", E. Paalvast, TR PL 89-ITI-B-18, Inst voor Toegepaste Informatica TNO, Delft, 1989. and the other fulfilling the regeneration requirements. This task would be difficult to achieve with a traditional one-mode hybrid system as a vast amount of electrical power would be required to keep the vehicle at a steady speed during trailering and climbing maneuvers. "It's a huge challenge for a single-mode hybrid system to do trailer towing because it has to process a vast amount of power through that electrical path. The four fixed gears give us huge potential to directly apply the engine to the output and it allows us to take the engine to power levels we wouldn't be able to with a one-mode certainly," Nitz says. In all, the two-mode system can operate in six different mechanical configurations: * Input-split EVT range * Compound split EVT range * First fixed gear ratio with electric boost/braking * Second fixed gear ratio with electric boost/braking * Third fixed gear ratio with electric boost/braking * Fourth fixed gear ratio with electric boost/braking. Production of the two-mode transmission will begin at GM's Baltimore, MD, Powertrain division plant beginning early next year as part of a $118-million investment in the facility. The transmissions will be sold to DaimlerChrysler for installation in the next-generation Dodge Durango SUV, while BMW and Mercedes will use the transmissions in various future passenger car and SUV applications. The partners say they plan to develop other derivatives of the transmission systems for use in smaller vehicles, while other partners are encouraged to join the team to see if this new mousetrap is better than the one already on the market.--KMK |
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