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A new concept of an electromagnetic torque converter for hybrid electric vehicles is proposed. The electromagnetic torque converter, which is an electric system comprised of a set of double rotors and a stator, works as a high-efficiency transmission in the driving conditions of low gear ratio including a vehicle moving-off and as a starting device for an internal combustion engine. Moreover, it can be used for an electric vehicle driving as well as for a regenerative braking. In this concept, a high-efficiency drivetrain system for hybrid electric vehicles is constructed by replacing a fluid-type torque converter with the electromagnetic torque converter in the automatic transmission of a conventional vehicle. In this paper, we present the newly developed electromagnetic torque converter with a compact structure that enables mounting on a vehicle, and we evaluate its transmission efficiency by experiment.

Toyota Motor Corporation developed the Multi Stage Hybrid System for the Lexus flagship LC500h coupe with the aim of achieving an excellent balance between fuel economy and acceleration performance. The Multi Stage Hybrid Transmission used in this new hybrid system includes a shift device located immediately after the power split device and motor. Compared with previous hybrid systems, acceleration performance is improved by increasing the driving force at low and medium vehicle speeds in lower gears, fuel economy and heat management performance are improved by reducing electrical loss by selecting the optimal gear depending on the driving state. The Multi Stage Hybrid Transmission uses a shift device with a wide gear ratio range to maximize both fuel economy and acceleration performance. The transmission was designed to achieve the appropriate size to be mounted in a new platform, as well as class-leading low noise levels for adoption in luxury vehicles.

An efficient approach to classify time series physical measurement data of shift control of automatic transmission for vehicles is presented. Comfortable acceleration is the essential factor of today’s vehicles. Shift control of automatic transmission of vehicles directly contributes to the comfortable acceleration. Since calibration of automatic transmission of vehicles is time consuming task for expert engineers, the development of autonomous calibration is desired to reduce product development period in today’s competitive automobile market. In the stage of product development, it is difficult to obtain a large amount of physical measurement data. Therefore, we need to develop machine learning method for limited amount of data. For this purpose, we develop the method to classify time series measurement data of shift control of automatic transmission of vehicles. We use support vector machine (SVM) as a machine learning technique.

This report proposes a rheological model and a thermal analysis model for oil films, which transmit power through a variator, as a prediction method for the maximum traction coefficient, and then describes the application and verification of this method. The rheological model expresses the conditions inside the contact ellipse using a combination of viscosity and plasticity. The thermal analysis model for oil films was confirmed by comparison of previously obtained temperatures directly measured from the traction contact area of the four-roller experimental apparatus [1]. The measurement used a thin-film temperature sensor and the consistency between the calculated and measured values was verified in the estimation model by reflecting the precise thermal properties of the thin film. Most values were consistent with the calculated values for the middle plane local shear heating model inside the oil film.

Toyota has developed a new belt-type continuously variable transmission (CVT) for 1.5-liter compact vehicles. To improve both driveability and fuel economy over previous CVTs, pressure management was adopted as the shift control method. The new shift control system was designed using a model-based control method which uses a two-degree-of-freedom system composed of feedback and feedforward controls. Smooth shifting in all the target shift speed regions was realized by combining a feedback loop that considers the output limit of the pulley thrust into the feedforward controller. Furthermore, shift response was improved while maintaining or even improving stability. This paper describes the details of this shift control system.

TOYOTA has developed the iQ with a 1.3L engine for the Scion brand in USA. Due to the importance of fun-to-drive factor for the Scion brand image, a responsive driving performance is required even with compact packaging and a small engine. In addition, because of the recent attention to global-warming and energy issues on a global scale, development of vehicles with high fuel economy is one of the most important issues for a car manufacturer. Therefore, it is necessary for a vehicle to have both high driving performance and fuel economy. TOYOTA has adopted the CVT-i as the transmission for this purpose. The following were achieved by adopting the CVT-i as the transmission for the iQ(1.3L). 1 Responsive driving performance with shift changes without a time lag. 2 Compact transmission for efficient vehicle packaging 3 Class-leading fuel economy performance. Moreover, it was developed with adjustments for the US market by improving the shift schedule for a linear acceleration feel.

Toyota has developed a new Hybrid (HV) transaxle P810 for Mid-Size SUVs to improve fuel efficiency and power performance. The transaxle was developed based on Toyota's new development strategy - Toyota New Global Architecture (TNGA). By adopting technologies to shorten overall length of the transaxle, installation into the same engine compartment of Mid-Size sedans have been realized while also improving the motor output. This paper will introduce technologies regarding the new mount structure for shortening overall length, and furthermore, noise reduction related to this mount structure.

For viscous couplings(VCs) as a driving force transmission system of vehicles, requirement of torque characteristics has been getting very stringent. Because the torque characteristics significantly affect four wheel drive vehicles' abilities such as traction performance and driving stability. Furthermore, the recent concerns on high fuel economy, low pollution and low cost require that design of VCs should be increasingly compact, light weighted and excellent in transmitted torque's stability. It is an easy way to increase viscosity of viscous coupling fluids(VCFs) for the compact design of the VC. But it might cause increase in heat load and wear of plates which resulted in degradation of the VCF. The degradation affects VCF's viscosity and impairs stability in torque transmission. Therefore it is indispensable to develop high viscosity VCF which is excellent in long-term viscosity's stability.

It has been past over 10 years since the slip-controlled clutch has adopted to torque converters as improvement technology of fuel consumption. In the recent trend, the updated demand is use of expanded slipping control for further improvement of the transmission efficiency. However, there are the cases of vibration issues in slip-controlled torque converter clutches. This issue is called shudder as typical problem of vehicle vibration. In design of torque converter, it is known as the importance to manage μ -V property preventing from shudder vibration. However, it was difficult to predict μ -V property on the actual system, because of its complex interface phenomena are caused by various changeable factors include physical and chemical. Therefore, if prototype design was never satisfied anti- shudder properties, we need to change design and lost much time to redesign it.

Toyota Motor Corporation has developed a new six-speed automatic transmission AB60E for longitudinal front engine rear wheel drive (RWD) vehicles. This transmission development was aimed at an improvement of power performance and fuel economy, while achieving a lightweight, compact package and a high torque capacity. In order to achieve this target, a high-capacity ultra-flat torque converter, a highly-rigid transmission case, and an ATF warmer with a valve to switch ATF circuits to an air-cooled ATF cooler have been newly developed. Moreover, a new transmission mode control logic “TOW / HAUL” has been developed to improve power performance and driveability during trailer towing. This automatic transmission has adopted the same gear train and hydraulic control system as the conventional six-speed automatic transmission A760E. This paper describes the structure, major features and performance of the transmission in detail.

TOYOTA has developed the world's first eight-speed automatic transmission (AA80E) for front-engine, rear-drive passenger cars. The AA80E developed for high-torque engines raises the level of power performance and fuel efficiency. To meet the size requirements needed for mounting in a passenger car application, an 8-speed geartrain, torque converter, transmission case and hydraulic control device were all newly-developed. Furthermore, the AA80E has benefited from technical developments to achieve an extremely high level of quietness and shifting performance. In this paper, the details of the AA80E are introduced.

Toyota has developed the world's first 8-speed automatic transmission (AA80E) for RWD automobiles. The transmission will first be used in the all-new Lexus LS460. In addition, a novel control system has been developed to maximize the predictability, response, efficiency, and initial quality of the powertrain while utilizing the high number of gear steps.

This paper demonstrates the development of a full multi-body vehicle model and its use in virtual design and troubleshooting of a vehicle response to throttle input. The multibody model is divided into three main subsystems: the chassis, the driveline and the powertrain subsystems. The chassis system includes a complete representation of both the front and the rear suspensions, both the front and rear subframes, and the vehicle body. The driveline system includes the output shafts from the transmission unit to the tires. The powertrain system includes complete representation of the cranktrain for a V6 combustion engine. Also included in the powertrain is a nonlinear representation of the gearbox where bearing clearances and gear lashes are considered. The cranktrain torque output is linked to the transmission using a torque converter model. The vehicle components are virtually assembled together through different joint types, force elements, and kinematic constraints.

Aisin AW Co., Ltd. was established in 1969 from Japanese and American investment as a new company specializing in automatic transmission (AT) manufacture. Aiming to reach and overtake the Western advanced technology while "pursuing the essence of the role of ATs within the whole vehicle system", it has since achieved its goal of becoming the world's No. 1 AT manufacturing company. In 1985, Aisin AW established a research and development lab for the development for new products other than ATs. Operating under the motto of creating a single, attractive basic design concept layout while "pursuing the essence of the role of the vehicle within society", this lab developed the world's first voice navigation system (VNS), an innovative, creative product born from our company's exclusive product concept. Aisin AW is now achieving the biggest share of the vehicle navigation system market in Japan

Transmission electron microscope (TEM) is a powerful tool for studying catalyst materials at nano-size and/or atomic level. Conventional TEM usually needs to be observed at room temperature in high vacuum conditions. A gaseous atmosphere and high temperature condition may change the properties of catalyst materials. Recently we developed an in situ observation system in TEM for observing the oxidation and reduction under a gas atmosphere at high temperature. Using the new in situ observation system in TEM, the morphological changes of the nano particle and support were observed in the heated gaseous atmosphere at atomic level in real time.

Toyota has developed a new sports shift control system introduced in the world's first eight-speed automatic transmission (AA80E), which is implemented in the “LS 460” and has been adopted in the “IS F” (upcoming 2008 model). This enables the IS F to be a vehicle that also permits the enjoyment of driving on circuits as well as achieving that “fun-to-drive” image. In sports driving, as achieved by the conventional torque converter-type automatic transmissions, shift response performance for shift operation and linearity performance for accelerator operations were challenges to tackle. On the contrary, the newly developed sports shift control system has resolved these challenges and enables the IS F to be capable of responding to a driver's intention quickly and accurately, letting the driver truly experience satisfaction.

As part of the International Lubricant Standardization and Approval Committee's (ILSAC) goal of developing a global automatic transmission fluid (ATF) specification, members have been evaluating test methods that are currently used by various automotive manufacturers for qualifying ATF for use in their respective transmissions. This report deals with comparing test methods used for determining torque capacity in friction systems (shifting clutches). Three test methods were compared, the Plate Friction Test from the General Motors DEXRON®-III Specification, the Friction Durability Test from the Ford MERCON® Specification, and the Japanese Automotive Manufacturers Association Friction Test - JASO Method 348-95. Eight different fluids were evaluated. Friction parameters used in the comparison were breakaway friction, dynamic friction torque at midpoint and the end of engagement, and the ratio of end torque to midpoint torque.

Continuously variable transmission (CVT) and hybrid systems, which have metal belts and electrical units not found in conventional transmissions, are susceptible to extremely High Frequency belt and electromagnetic noise between 5 to 10 kHz. The evaluation and reduction of high frequency (HF) noise of 5 kHz and more is therefore a critical point for improving the quietness of vehicles installed with such systems. This article describes new sound source search technology capable of identifying sources of noise up to 15 kHz in the vehicle interior. Unlike conventional beamforming methods, this new system uses an improved microphone array provided with additional acoustic material. This article outlines the development of the system and its application to sound source identification of HF noise in a hybrid vehicle.

AISIN AW has developed a six-speed automatic transmission TF-60SN for front wheel drive (FWD) vehicles. This new TF-60SN has been developed based on the concepts of minimizing length and mass increase as compared with current five-speed automatic transmissions, and providing the world's first transverse FWD six-speed automatic transmission. This has been accomplished using a newly developed planetary gear set, and a new “squeezed” torque converter. In addition, the control system features a unique design that maintains outstanding compactness and achieves a high quality smooth shift feeling. This paper describes the construction, characteristics, and functions of this six-speed automatic transmission.

AISIN AW has developed a five-speed automatic transmission “55-50SN” for front wheel drive (FWD) vehicles. This new 55-50SN has been developed with a concept to minimize length and mass increase compared with the current four-speed automatic transmission, and is one of the most compact five-speed automatic transmissions in the world. This has been accomplished by newly developed planetary gear sets, a new differential, and a new squeezed torque converter. In addition, the control system is made by a unique design to maintain the excellent compactness and to achieve a high quality smooth shift feeling. This paper describes the construction, characteristic, and function of this five-speed automatic transmission.