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In the 42V Mild Hybrid System introduced into market by Toyota for the first time in the world, the crankshaft using belt(s) drives the motor/generator (MG). The set-up employs an inverter unit to control the MG electronically. This paper describes the system configuration, operations, characteristic features and development results of the new power control system. The focus is on the MG, the inverter-for-MG-control and energy regeneration, as well as DC/DC converter for the power supply to the 14V devices.

A silicon micromachined gyroscope (angular rate sensor, yaw rate sensor) and accelerometer for vehicle stability control system is presented. The 5.1mm×4.7mm sensor chip is fabricated with a silicon micromachining process using a SOI (Silicon on Insulator) silicon wafer and a deep reactive ion etching. The sensor chip has a pair of resonators which are mechanically coupled and function as a tuning fork. The resonators are driven by electrostatic force and their movements are detected by capacitively sensing angstrom displacements. This sensor chip works not only as a gyroscope but also as an accelerometer with a single sensor chip. The sensor unit consists of the sensor chip above, a signal processing IC, a microcomputer and an EEPROM. sigma-delta analog-to-digital conversion (sigma-delta ADC) is adopted to realize the digital calibration of sensor properties.

Previous studies have investigated the impacts of biofuel usage on the performance, drivability and durability of modern diesel engines and exhaust after-treatment systems including test work with different types, concentrations and mixtures of bio fuel components. During this earlier work vehicle fuel filter blocking issues were encountered during a field trial using various types of EN 14214 compliant Fatty Acid Methyl Ester (FAME) blended into EN 590 diesel. This paper summarises a subsequent literature review that was carried out looking into potential causes of this filter blocking and further work that was then carried out to expand on the findings. From this, a laboratory study was carried out to assess the increase in fuel filter blocking tendency (FBT) when various FAMEs from mixed sources were blended into EN 590 diesel at different concentrations, including levels above those currently allowed in the European market.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

This paper considers an application of reference governor (RG) to automotive diesel aftertreatment temperature control. Recently, regulations on vehicle emissions have become more stringent, and engine hardware and software are expected to be more complicated. It is getting more difficult to guarantee constraints in control systems as well as good control performance. Among model-based control methods that can directly treat constraints, this paper focuses on the RG, which has recently attracted a lot of attention as one method of model prediction-based control. In the RG, references in tracking control are modified based on future prediction so that the predicted outputs in a closed-loop system satisfy the constraints. This paper proposes an online RG algorithm, taking account of the real-time implementation on engine embedded controllers.

Since the regulations of CO2 emissions have been tightened in each country recently, each automotive manufacturer has responded by bringing competitive technologies that maximize efficiency while promoting vehicle electrification such as xEV. Not only the efficiency, we need to meet or exceed occupant performance and comfort expectations. The climate control system expends a large amount of energy to keep a comfortable environment, having a significant impact on fuel consumption and EV driving range. Therefore, many manufacturers try to save energy and improve occupant comfort quickly by using not only the conventional convective heating by HVAC but also the conductive heating to heat the human body directly such as seat and steering wheel heater. In this study, a radiative heater, which is more efficient than a convective heating to warm anterior thigh and shin where a conductive heating cannot warm, was applied to vehicle.

As requirements for protecting the global environment are being heightened on a worldwide scale in recent years, the development of low fuel consumption technologies in order to inhibit the discharge of CO2 is an important issue for the automotive industry. Recently, Toyota has developed a Super CVT for the 1.3-to 1.5-liter class vehicles to further improve their fuel economy. This CVT has been adopted on vehicles equipped with the ‘idling stop system’. The ‘idling stop system’ automatically stops the engine when the vehicle is stopped and the transmission shift lever is in the ‘D’ position (e.g. when the vehicle is at a stoplight). This improves the fuel economy of the vehicle by eliminating fuel consumption while the vehicle is stopped. The conventional CVT poses unique conditions such as startoff time lag or shock after the engine is restarted. These conditions occur because the CVT oil pump cannot generate hydraulic pressure while the engine is stopped.

Teammate Advanced Drive is a driving support system with state-of-the-art automated driving technology that has been developed for customers’ safe and secure driving on highways based on the Toyota’s Mobility Teammate Concept. This SAE Level 2 (L2) system assists overtaking, lane changes, and branching to the destination, in addition to providing hands-free lane centering and car following. The automated driving technology includes self-localization onto a High Definition Map, multi-modal sensing to cover 360 degrees of the surrounding environment using fusion of LiDARs, cameras, and radars, and a redundant architecture to realize fail-safe operation when a malfunction or system limitation occurs. High-performance computing is provided to implement deep learning for predicting and responding to various situations that may be encountered while driving.

According to the U.S. National Highway Traffic Safety Administration, 743 pedal cyclists were killed and 48,000 were injured in motor vehicle crashes in 2013. As a novel active safety equipment to mitigate bicyclist crashes, bicyclist Pre-Collision Systems (PCSs) are being developed by many vehicle manufacturers. Therefore, developing equipment for evaluating bicyclist PCS is essential. This paper describes the development of a bicycle carrier for carrying the surrogate bicyclist in bicyclist PCS testing. An analysis on the United States national crash databases and videos from TASI 110 car naturalistic driving database was conducted to determine a set of most common crash scenarios, the motion speed and profile of bicycles. The bicycle carrier was designed to carry or pull the surrogate bicyclist for bicycle PCS evaluation. The carrier is a platform with a 4 wheel differential driving system.

This paper describes a new control technology that coordinates the operation of multiple actuators in a new hybrid electric vehicle (HEV) system consisting of a turbocharged engine, front and rear electric motors, two clutches, and a 6-speed automatic transmission. The development concept for this control technology is to achieve the driver’s desired acceleration G with a natural feeling engine speed. First, to realize linear acceleration G even while the engine is starting from EV mode, clutch hydraulic pressure reduction control is implemented. Furthermore, the engine start timing is optimized to prevent delayed drive force response by predicting the required maximum power during cranking. Second, to realize linear acceleration, this control selects the proper gear position based on the available battery power, considering noise and vibration (NV) restrictions and turbocharging response delays.

Toyota Motor Corporation has already designed and developed vehicle brake control systems for relatively low speed off-road driving, such as Downhill Assist Control, Hill-start Assist Control and Active Traction Control. Though off-road utility is improved by virtue of these systems, in specific situations actual performance still depends on driving technique since the driver is required to control the accelerator pedal. Toyota has integrated these existing systems, and developed a new driving technology for off-road driving called “Crawl Control.” Crawl Control automatically modulates brake torque and drive torque to help keep the vehicle speed constant and slow. Unskilled drivers can thereby attain improved capabilities in places where high-level driving techniques are required. This system also reduces the effort required to control the accelerator and the brake pedal. This paper presents a new control algorithm for the realization of this Crawl Control system.

Over the past decades, the automotive industry has made significant efforts to improve engine fuel economy by reducing mechanical friction. Reducing friction under cold conditions is becoming more important in hybrid vehicle (HV) and plug-in hybrid vehicle (PHV) systems due to the lower oil temperatures of these systems, which results in higher friction loss. To help resolve this issue, a new internal gear fully variable discharge oil pump (F-VDOP) was developed. This new oil pump can control the oil pressure freely over a temperature range from -10°C to hot conditions. At 20°C, this pump lowers the minimum main gallery pressure to 100 kPa, thereby achieving a friction reduction effect of 1.4 Nm. The developed oil pump achieves a pressure response time constant of 0.17 seconds when changing the oil pressure from 120 kPa to 200 kPa at a temperature of 20°C and an engine speed of 1,600 rpm.

The new P710 hybrid transaxle for a mid-size 2.5-liter class vehicle was developed based on the Toyota New Global Architecture (TNGA) design philosophy to achieve a range of desired performance objects. A smaller and lighter transaxle with low mechanical loss was realized by incorporating a new gear train structure and a downsized motor. The noise of the P710 transaxle was also reduced by adopting a new damper structure.

A new shift control system using a model-based control method for stepped automatic transmissions. Using a gear train numerical formula model, the model-based shift control system is constructed using minimum calibration parameters with feedforward and feedback controllers. It also adopts control target values for the input shaft revolution and output shaft torque, thus enabling precise control that provides the most suitable shift feeling in various driving situations and for various vehicle characteristics. Furthermore, the model-based shift control system improves robustness in terms of disturbance elements such as production tolerance, time degradation, and use environment. Toyota has adopted this model-based shift control system in its UA80/UB80 8-speed automatic transmissions for front-wheel-drive vehicles and its AGA0 10-speed automatic transmission for rear-wheel-drive vehicles. This paper describes the details of this model-based shift control system.

Toyota Motor Corporation began leasing a new generation fuel cell vehicle the FCHV (Fuel Cell Hybrid Vehicle) in December 2002. That vehicle includes a new variable voltage power electronics system and uses the Nickel Metal Hydride (Ni-MH) battery system from the Prius hybrid gasoline electric vehicle. This paper describes on-going efforts to model optimum secondary storage systems for future vehicles. Efficiency modeling is presented for the base Ni-MH storage system, an ultra capacitor system and a Lithium ion (Li-ion) battery system. The Li-ion system in combination with a new high efficiency converter shows a 4% improvement in fuel economy relative to the base system. The ultra capacitor system is not as efficient as the base system.

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 Motor Corporation developed a new hybrid system, Multi Stage Hybrid System, for the Lexus flagship coupe LC500h 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, the new hybrid system improves fuel economy by reducing electrical loss in the optimal gears, which are selected depending on the driving state. The system also improves acceleration performance by increasing the driving force at low and medium vehicle speeds in lower gears. In addition, the range of the power split device that cooperates with the shift device was widened to enable both an electrically-controlled continuously variable transmission mode and a ten-speed transmission mode, which creates a direct shift feeling to improve driving pleasure.

This paper describes the development of dummy FE models to be used for side impact simulations. The precise geometries of the ES-2re dummy and the SID-IIs dummy were measured at a pitch of 1.0 mm using X-ray CT scan. The material properties and the mechanical responses of the components were measured in static and dynamic tests and were used for the model validation. The models were further validated to US-NCAP side impact requirements. Good correlation was seen for both response time history, and to peak deformation values. It is shown that modeling the precise dummy internal structure in addition to the external geometry and applying accurate material properties enabled simulation of deformation kinematics and load transfer inside the dummies. As a result, it was possible to accurately simulate the injury value time histories in an actual test, and understand the mechanisms causing changes to the loading.

The second-generation air-fuel ratio control method has been developed to reduce exhaust gas emissions in accordance with the improvements in catalysts. The control system consists of a feedforward control using a fuel behavior model, a feedback control using an universal exhaust gas oxygen (UEGO) sensor and a feedback control utilizing the heated exhaust gas oxygen (HEGO) sensor. This significantly improves air-fuel ratio tracking performance by feedforward control derived from the models that express the dynamic phenomena and the disturbance attenuation by UEGO feedback controller which compensates for the long dead-time characteristics by the state predictive control. The tracking performance and the disturbance attenuation can be achieved independently by a two-degree-of-freedom structure presented in this paper. The exhaust air-fuel ratio downstream of the catalyst precisely converges to stoichiometry, which maximizes the conversion efficiency of the catalyst.