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Despite the legislation targets set by several governments of a full electrification of new light-duty vehicle fleets by 2035, the development of innovative, environmental-friendly Internal Combustion Engines (ICEs) is still crucial to be on track toward the complete decarbonization of on road-mobility of the future. In such a framework, the PHOENICE (PHev towards zerO EmissioNs & ultimate ICE efficiency) project aims at developing a C SUV-class plug-in hybrid (P0/P4) vehicle demonstrator capable to achieve a -10% fuel consumption reduction with respect to current EU6 vehicle while complying with upcoming EU7 pollutant emissions limits. Such ambitious targets will require the optimization of the whole engine system, exploiting the possible synergies among the combustion, the aftertreatment and the exhaust waste heat recovery systems.

Investigations of injuries from automobile accidents are of limited valve unless they can be correlated with the severity of the accident. In order to provide a uniform base of accident severity, a method for relating the severity of impact to different types of objects to the barrier impact has been developed. The barrier impact is used as the reference since it is the most severe type of accident. The result is an effective barrier speed which relates the severity of the accident to an equivalent barrier speed.

We investigated and analyzed the average vehicle-driver's braking behavior in panic situations by conducting vehicle tests that duplicated real world conditions that would require emergency braking performance. From our investigation, we have noticed that when panic braking is recognized, supplying additional braking power is effective for active safety. The Brake Assist System, which supplies full constant braking force when panic braking is recognized, is effective for drivers who cannot apply enough braking effort. However, in some case, such a system makes more experienced drivers uncomfortable because the deceleration caused by this full constant braking force might be different from their intentions. Considering these issues, we have developed the Brake Assist System that increases its controllability while reducing its discomfort. The TOYOTA RAUM has been available with the Brake Assist System since May 1997.

For the launch of the redesigned Lexus LS, a new 3.5 L V6 twin turbo engine has been developed aiming at unparalleled performance on four axes, “driving pleasure”, “power-performance”, “quietness” and “fuel economy”. To achieve outstanding power-performance and high thermal efficiency, the specifications have been optimized for high speed combustion. The maximum torque of 600 Nm, power of 310 kW (yielding specific power of 90 kW/L), and the maximum thermal efficiency of 37% have been achieved using several new technologies including a high efficiency turbocharger. A prototype vehicle equipped with this engine and Direct-Shift 10AT achieved a 0-60 mph acceleration time of 4.6 sec, with extremely good CAFE combined fuel economy of 23 mpg and power-performance aligned with V8 turbocharged offerings from competing OEM’s.

Road vehicles in the real world experience aerodynamic conditions that might be unappreciated and omitted in wind-tunnel experiments or in numerical simulations. Precipitation can potentially have an impact on the aerodynamics of road vehicles. An experimental study was devised to measure, in a wind tunnel, the impact of rain on the aerodynamic forces of the DrivAer research model. In this study, a rain system was commissioned to simulate natural rain in a wind-tunnel environment for full-scale rain rates between about 8 and 250 mm/hr. A 30%-scale DrivAer model was tested with and without precipitation for two primary configurations: the notch-back and estate-back variants. In addition, mirror-removal and covered-wheel-well configurations were investigated. The results demonstrate a distinct relationship between increasing rain intensities and increased drag of the model, providing evidence that road vehicles experience higher drag when travelling in precipitation conditions.

This article compares the results of automotive accident reconstructions to event data recorder (EDR) data from vehicles involved in rear-end collisions. Accident reconstructions in the Crash Investigation Sampling System (CISS) database calculate crash severity expressed as the impact-related change in velocity (delta-V) experienced by a vehicle. The accuracy of the CISS-reconstructed delta-V in rear impacts was assessed by comparison to the delta-V recorded during the crash by the EDR on board the rear-ended vehicles. The CISS database was searched for single rear impact cases with a CISS-reconstructed delta-V as well as an EDR download. A total of 256 cases met these criteria. On average, the CISS-reconstructed delta-V was 4.0% lower than the delta-V recorded by the EDR. The accuracy of the CISS reconstructions varied with crash configuration, vehicle type, collision partner, and crash severity.

Knowing the tire pressure during driving is essential since it affects multiple tire properties such as rolling resistance, uneven wear, and how prone the tire is to tire bursts. Tire temperature and cavity pressure are closely tied to each other; a change in tire temperature will cause an alteration in tire cavity pressure. This article gives insights into which tire temperature measurement position is representative enough to estimate pressure changes inside the tire, and whether the pressure changes can be assumed to be nearly isochoric. Climate wind tunnel and road measurements were conducted where tire pressure and temperature at the tire inner liner, the tire shoulder, and the tread surface were monitored. The measurements show that tires do not have a uniform temperature distribution. The ideal gas law is used to estimate the tire pressure from the measured temperatures.

This paper presents a numerical model of a Polymer Electrolyte Membrane Fuel Cell (PEMFC) system reproducing an automotive-type powertrain. The 0D model is developed in MATLAB/Simulink environment, and it incorporates all the main auxiliary components (air and hydrogen supply line, cooling circuit) as well as the PEMFC stack unit. The model includes an ageing model to estimate the PEMFC stack degradation over time, resulting in progressive efficiency loss as well as in increased auxiliary power and thermal dissipation demand. The presented model enables the estimation of both PEMFC duration and of the time-varying request of heat rejection, facilitating the selection of auxiliaries to optimize the lifelong performance. The model constitutes the backbone for the design and optimization of PEMFC systems for automotive applications, and the integration with a degradation model provides a comprehensive research tool to estimate the long-term performance and lifetime of PEMFC system.