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Regulations that limit emissions of pollutants from gasoline-powered cars and trucks continue to tighten. More than 75% of emissions through an FTP-75 regulatory test are released in the first few seconds after cold-start. A factor that controls the time to catalytic light-off is the heat capacity of the catalytic converter substrate. Historically, substrates with thinner walls and lower heat capacity have been developed to improve cold-start performance. Another approach is to increase porosity of the substrate. A new material and process technology has been developed to significantly raise the porosity of thin wall substrates (2-3 mil) from 27-35% to 55% while maintaining strength. The heat capacity of the material is 30-38% lower than existing substrates. The reduction in substrate heat capacity enables faster thermal response and lower tailpipe emissions. The reliance on costly precious metals in the washcoat is demonstrated to be lessened.

We developed a windshield washer system that enhances washing performance while maintaining low consumption of windshield washer fluid. The system reduces user stress by shortening the amount of time required to remove dirt and maintaining visibility through the windshield. We analyzed the mechanism through which the windshield wiper and windshield washer remove dirt from the glass surface to improve cleaning efficiency. The mechanism consists of a sequence in which the windshield washer fluid splashes down on the glass surface and lifts dirt which is then wiped away by the windshield wiper blade. We defined the amount of windshield washer fluid needed and the time from splashdown to wiping required to lift dirt and wipe it away with the wiper. Based on this mechanism, we developed a wiper arm with built-in washer nozzles.

Amidst the rising demand to reduce CO2 and other greenhouse gas emissions in recent years, gasoline homogeneous-charge compression ignition (HCCI) has gained attention as a technology that achieves both low NOx emissions and high thermal efficiency by means of lean combustion. However, gasoline HCCI has low robustness toward intracylinder temperature variations, therefore the problems of knocking and misfiring tend to occur during transient operation. The authors verified the transient operation control of HCCI by using a 4-stroke natural aspiration (NA) gasoline engine provided with direct injection (DI) and a variable valve timing and a lift electronic control system (VTEC) for intake air and exhaust optimized for HCCI combustion. This report describes stoichiometry spark ignition (SI) to which external exhaust gas recirculation (EGR) was introduced, HCCI ignition switch control, and changes in the load and number of engine revolutions in the HCCI region.

The superior formability and local ductility of the emerging class of third generation of advanced high-strength steels (3rd Gen AHSS) compared to their conventional counterparts of the same strength level offer significant advantages for automotive lightweighting and enhanced crash performance. Nevertheless, studies on the material behavior of 3rd Gen AHSS have been limited and there is some uncertainty surrounding the applicability of developed methodologies for conventional dual-phase (DP) steels to this new class of AHSS. The present paper provides a comprehensive study on the quasi-static and dynamic constitutive behavior, formability characterization and prediction, and the fracture behavior of two commercial 3rd Gen AHSS with an ultimate strength of 1180 MPa that will be contrasted with a conventional DP1180. The hardening response to large strain levels was determined experimentally using tensile and shear tests and then validated with 3-D simulations of tensile tests.

A new hybrid system has been developed to increase the permissible system weight and raise dynamic performance/system efficiency for the global rollout of Honda's electric vehicles. The powertrain consists of a 2.0L direct injection engine, a Front Drive Unit (FDU) with a built-in traction motor/generator and gear that directly transmit engine torque to the wheels (engine driving gear), a Power Control Unit (PCU) mounted on the FDU, and an Intelligent Power Unit (IPU) mounted under the cargo area. The FDU has a higher RPM (+12%) and higher torque (+6%) traction motor for enhanced launch acceleration performance and maximum vehicle speed settings tailored to regional needs. In addition, a new engine driving gear for low-speed driving has been added to heighten system efficiency by avoiding traction motor driving in low-speed, high-load areas where electrical losses are high, and instead using a driving mode with an engine driving gear (ENGINE MODE).