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To improve the fuel economy, we developed a turbo-charged spark ignition engine combined with a low pressure loop EGR system. A negative pressure control valve has been applied to achieve high EGR ratio in wide engine operation condition. In this paper, a new developed model-based control system for low pressure loop EGR with a negative pressure control valve will be described.

There are two primary technical issues in the application of position sensorless control to generators for 100% electric-drive hybrid vehicles. The first is the risk of losing control when position sensorless estimation methods are changed in accordance with the generator speed, while. The second is the reduction in the maximum torque if the rate of change in the generator speed is extremely large in a relatively low-rotation-speed area. This study proposes countermeasures for each issue and their effects examines them via simulations and experiments.

The size and weight of the traction inverter needs to be reduced to ensure a sufficient cruising range of an electric vehicle. To this end, one approach involves changing materials of the inverter case from aluminum to resin. However, the resin in use of inverter case causes technical issues in terms of collision performance, electromagnetic compatibility (EMC), and cooling performance because of the difference in the material properties between the resin and the conventionally used aluminum. By solving the abovementioned issues, a resin water jacket case (hereinafter, resin water jacket) was successfully adopted with inverters designed for next-generation electric powertrain in mass production models for the first time. The resin-based structure had advantages to reduce the weight of the inverter case by ~35% and decrease the number of parts to ~3/5, compared to that for the conventional cases.

There are many production robots used at car manufacturing plants, and each of them is fitted with several reducers. A breakdown of one of these reducers may cause a huge loss due to the stoppage of all production lines. Therefore, condition-based maintenance is currently being used to predict failures by predetermined thresholds for average and standard deviations. However, this method can cause many false alarms or some false negatives. There are some ways of suppressing false alarms, such as detecting a change in the probability density function. However, when false alarms are suppressed using the probability density function in the operational range, some false negatives may occur, leading to a breakdown of a reducer and huge loss. A false negative is caused by overlooking an anomaly with slight changes and it is difficult to detect using only the probability density function.

Vehicle-to-Grid (V2G) technology is expected to play a role in addressing the imbalance between periods of peak demand and peak supply on the electricity grid. V2G technology enables two-way power flow between the grid and the high-power, high-capacity propulsion battery in an electrified vehicle. That is, V2G enables a balance between power demand and supply, which is becoming difficult due to the introduction of intermittent sources of renewable energy. The authors have shown through system simulations that bi-directional wireless power transfer (WPT) is possible with a system that meets the emerging SAE J2954 standard. Based on the result, the authors have also demonstrated a bi-directional wireless charging system for V2G applications. In this work an existing SAE J2954 compatible uni-directional system was adapted to enable bi-directional wireless power transfer with minimum impact to system cost, while maintaining full compatibility with the requirements of SAE J2954.

Wireless Power Transfer (WPT) promises automated and highly efficient charging of electric and plug-in-hybrid vehicles. As commercial development proceeds forward, the technical challenges of efficiency, interoperability, interference and safety are a primary focus for this industry. The SAE Vehicle Wireless Power and Alignment Taskforce published the Recommended Practice J2954 to help harmonize the first phase of high-power WPT technology development. SAE J2954 uses a performance-based approach to standardizing WPT by specifying ground and vehicle assembly coils to be used in a test stand (per Z-class) to validate performance, interoperability and safety. The main goal of this SAE J2954 bench testing campaign was to prove interoperability between WPT systems utilizing different coil magnetic topologies. This type of testing had not been done before on such a scale with real automaker and supplier systems.

A toroidal variator is the core part of an advanced Continuously Variable Transmission (CVT) design. Knowing its behavior and internal forces is key to defining the operational conditions of the transmission. To maintain a steady-state speed ratio, or to accurately and efficiently move between speed ratios, optimal trunnion control force is required. The unique design of the toroidal CVT makes the design very sensitive to trunnion positioning and force transients. Analytical understanding of the mechanism response is critical to toroidal variator controller design. A critical feature of the toroidal CVT simulation is representation of the friction forces in the disk-roller contact. This effect is important to the mechanism torque capacity and efficiency.

A new hydrogen fueling protocol named MC Formula Moto was developed for fuel cell motorcycles (FCM) with a smaller hydrogen storage capacity than those of light duty FC vehicles (FCV) currently covered in the SAE J2601 standard (over than 2kg storage). Building on the MC Formula based protocol from the 2016 SAE J2601 standard, numerous new techniques were developed and tested to accommodate the smaller storage capacity: an initial pressure estimation using the connection pulse, a fueling time counter which begins the main fueling time prior to the connection pulse, a pressure ramp rate fallback control, and other techniques. The MC Formula Moto fueling protocol has the potential to be implemented at current hydrogen stations intended for fueling of FCVs using protocols such as SAE J2601. This will allow FCMs to use the existing and rapidly growing hydrogen infrastructure, precluding the need for exclusive dispensers or stations.

A CVT variator chain system is superior in transmission efficiency to a belt system because of its lower internal friction. However, a chain produces more noise than a belt due to the long pitch length of contact between the pulleys and rocker pins. This study focuses on optimization of the pitch sequence for reducing chain noise. The previous pitch sequence was suitably combined of links of different lengths to improve noise dispersibility for reducing chain noise. First, the object function was defined as the reduction of the peak level of 1st-order chain noise combined with a well-balanced the levels on the low and high frequency sides. Interior background noise consisting of road noise and wind noise have the characteristic that they increase as the frequency decreases.

This paper presents the technologies incorporated in an electric vehicle (EV)/hybrid electric vehicle (HEV) inverter built with power semiconductors of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) instead of conventional silicon (Si) insulated gate bipolar transistors (IGBTs). A SiC inverter prototype of 2.9 L in size for driving an 80-kW motor was fabricated and evaluated on a motor test bench. The SiC inverter prototype attained average efficiency of 98.5% in the Worldwide harmonized Light-duty Test Cycle (WLTC) driving mode. The two main technologies achieved with this SiC inverter prototype are described. The first one is a new direct-cooled power module with a thick copper (Cu) heat spreader located under the semiconductors that improves thermal resistance by 34% compared with a conventional direct-cooled power module.

Because of rising demands to improve aerodynamic performance owing to its impact on vehicle dynamics, efforts were previously made to reduce aerodynamic lift and yawing moment based on steady-state measurements of aerodynamic forces. In recent years, increased research on dynamic aerodynamics has partially explained the impact of aerodynamic forces on vehicle dynamics. However, it is difficult to measure aerodynamic forces while a vehicle is in motion, and also analyzing the effect on vehicle dynamics requires measurement of vehicle behavior, amount of steering and other quantities noiselessly, as well as an explanation of the mutual influence with aerodynamic forces. Consequently, the related phenomena occurring in the real world are still not fully understood.

Mechanism of suddenly occurring behavior of low speed pre-ignition (LSPI) in boosted spark ignition (SI) engines was analyzed with various experimental methodologies. Endoscope-visualized 1st cycle of LSPI showed droplet-like luminous flame kernels as the origin of flame propagation before spark ignition. With the oil lubricated visualization engine, droplets flying were observed only after enough accumulation of fuel at piston crevice. Also, it was confirmed that subsequent cycles of LSPI occur only after enough operation time. These results indicated that local accumulation of liner adhered fuel and saturation of oil dilution can be a contributing factor to the sudden occurrence of LSPI.

Road Noise is generated by the change of random displacement input inside the tire contact patch. Since the existing 3 or 6 directional electromagnetic shakers have a flat surface at the tire contact patch, these shakers cannot excite the vehicle in a manner representative of actual on-road road noise input. Therefore, this paper proposes a new experimental method to measure the road noise vehicle transfer function. This method is based on the reciprocity between the tire contact patch and the driver's ear location. The reaction force sensor of the tire contact patch is newly developed for the reciprocal loud speaker excitation at the passenger ear location. In addition, with this equipment, it is possible to extract the dominant structural mode shapes creating high sound pressure in the automotive interior acoustic field. This method is referred to as experimental structure mode participation to the noise of the acoustic field in the vibro-acoustic coupling analysis.

Dedicated Short Range Communications (DSRC) for vehicle-to-vehicle (V2V) cooperative applications for advanced safety is becoming a reality. Many automotive manufactures are entering advanced research phases or even planning deployments of such applications in the near future. However, the success of most V2V applications requires full or near-full deployment of the DSRC devices in new and existing vehicles, which will take many years to accomplish. In the meantime, use of autonomous sensors in combination with V2V can augment this deployment transitional period. In this paper we propose a hybrid approach that uses autonomous sensors to rebroadcast information about unequipped neighboring vehicles. In addition to messages that a host vehicle sends about its own state (such as position, speed, and direction), additional sensing capabilities also allow sending information about neighboring vehicles. This information can be obtained from radars, cameras and other autonomous sensors.

There has been a growing need in recent years to further improve vehicle fuel efficiency and reduce CO2 emissions. JATCO began mass production of a transmission for rear-wheel-drive (RWD) hybrid vehicle with Nissan in 2010, which was followed by the development of a front-wheel-drive (FWD) hybrid system (JATCO CVT8 HYBRID) for use on a midsize SUV in the U.S. market. While various types of hybrid systems have been proposed, the FWD system adopts a one-motor two-clutch parallel hybrid topology which is also used on the RWD hybrid. This high-efficiency system incorporates a clutch for decoupling the transmission of power between the engine and the motor. The hybrid system was substantially downsized from that used on the RWD vehicle in order to mount it on the FWD vehicle. This paper describes various seal technologies developed for housing the dry multi-plate clutch inside the motor, which was a key packaging technology for achieving the FWD hybrid system.

Many Intelligent Transportation System (ITS) technologies have been developed to improve the safety and efficiency of cars, trucks, public transport and infrastructure. However, very few ITS have been developed specifically for the motorcycle user protection. In this paper an analysis of dynamic and static communications tests between a vehicle and two motorcycles are provided. The system enables vehicles and motorcycles to exchange safety information such as speed, heading, location, and brake status through the use of 5.9 GHz Dedicated Short Range Communication (DSRC) protocol. The vehicles and motorcycles can then assess the potential threat level based on the incoming messages from the nearby traffic. Several high-impact motorcycle-to-vehicle collision scenarios are analyzed. Technical challenges, such as motorcycle wireless unit antenna direction performance, communication performance and target classification accuracy are further investigated.

A flag is a global boolean variable used to achieve synchronization between various tasks of an embedded system. An application implementing flags performs actions or events based on the value of the flags. If flag variables are not implemented properly, certain synchronization related issues can arise which can lead to unexpected behavior or failure of the underlying system. In this paper, we present an automated verification technique to identify and verify flag usage patterns at an early stage of code development. We propose a two-step approach which consists of: a. identification of all potential flag variables and b. verification of flag usage patterns against predefined set of rules. The results of our experiment demonstrate that the proposed approach reduces the cost and complexity of the flag review process by almost 70%.

The new Jatco CVT8 High Torque (CVT8 HT) was developed for use on front-wheel-drive vehicles fitted with a large displacement engine. The development objectives set for this new CVT with a high torque capacity were outstanding fuel economy, size and weight reductions. To achieve those targets, a high torque capacity CVT chain was newly developed in cooperation with LuK GmbH & Co. KG. This article describes the efforts undertaken to develop increasing torque capacity.

This paper reports about a trial for miniaturization of an air-cooled inverter integrated with motor, which is realized by reduction of the total volume of smoothing capacitor. An integrated system prototype was constructed with a disk-shaped inverter positioned at the rear end of the motor. We examined the possibility of using a ceramic capacitor, which features a higher heat-resistance temperature, lower internal resistance and higher capacity density than a film capacitor. At the same level of capacitance, the volume of a ceramic capacitor is less than one-half that of a film capacitor, enabling the size of the smoothing capacitor to be reduced to approximately one-fifth that of the currently used device. A suitable circuit configuration and physical layout of distributed smoothing capacitors and corresponding power device modules are proposed and demonstrated.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.