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Technical Paper

A Comparison of Methods for Evaluating Automatic Transmission Fluid Effects on Friction Torque Capacity - A Study by the International Lubricant Standardization and Approval Committee (ILSAC) ATF Subcommittee

1998-10-19
982672
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.
Technical Paper

The Development of Toyota Fantasy Print System

1998-09-29
982344
Recently, the demands of vehicle owners have become more diversified. This is particularly true in the paint appearance of the vehicle. Responding to these demands Toyota has developed an ink jet painting system, Toyota Fantasy Print System. This system can illustrate practically any picture which the customer desires. The system utilized a subtractive method of paint mixture which mixes or piles up these four permeable inks. The development of durable ink as well as equipment which can efficiently and effectively apply the ink onto the required contoured surface.
Technical Paper

High Toughness Microalloyed Steels for Vital Automotive Parts

1989-02-01
890511
We developed new microalloyed steels, containing about 0.05% sulfur, which have excellent as hot-forged toughness even when forged at the temperatures of about 1300°C(2375°F). We also estimated the various properties of the new microalloy steel in the as hot-forged condition, comparing them to quench and tempered SAE1055 steel used in the front axle of a small truck. The results showed the new steel has improved yield strength, fatigue strength, absorbed impact energy and machinability over the SAE1055 steel.
Technical Paper

Development of a Mechanical Pilot Injection Device for Automotive Diesel Engines

1989-09-01
891962
It is well known that pilot injection is an effective method of reducing diesel knock noise during idling, but no actual system has as yet been commercially produced. With the objective of developing a practicable pilot injection device, simulations were conducted of various simple mechanisms in order to determine the best specifications and analyze the fuel injection characteristics. Based on these results, a chamber expansion type pilot injection device, which enables the injection pump pressure chamber volume to be increased at a given moment during the fuel compression stroke, has been developed and has been found to remarkably decrease knock noise during cold idling. An investigation into the effects of this device on output power, exhaust emissions, cold startability and durability revealed that it is eminently suitable for practical application.
Technical Paper

Development of CFD Inverse Analysis Technology Targeting Heat or Concentration Performance Using the Adjoint Method and Its Application to Actual Components

2018-04-03
2018-01-1033
To resolve two major problems of conventional CFD-based shape optimization technology: (1) dependence of the outcome on the selection of design parameters, and (2) high computational costs, two types of innovative inverse analysis technologies based on a mathematical theory called the Adjoint Method were developed in previous studies for maximizing an arbitrary hydrodynamic performance aspect as the cost function: surface geometry deformation sensitivity analysis to identify the locations to be modified, and topology optimization to generate an optimal shape. Furthermore, these technologies were extended to transient flows by the application of the transient Adjoint Method theory. However, there are many cases around flow path shapes in vehicles where performance with respect to heat or concentration, such as the total amount of heat transfer or the flow rate of a specific gas component, is very important.
Technical Paper

A Study of Mixed-FAME and Trace Component Effects on the Filter Blocking Propensity of FAME and FAME Blends

2010-10-25
2010-01-2116
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.
Technical Paper

Development of Anti Scratch Clear Coat

2008-04-14
2008-01-1461
“Anti-scratch performance” is the highest in customer's needs of paint. To achieve anti-acid and anti-scratch performance, we selected 2K-urethane because of a high degree of freedom in paint design. In addition, we have done a precise molecular design of the acrylic polyol and the isocyanate. As a result, “a highly durable, soft, fine-crosslinking paint film” was achieved, and “anti-scratch clear coat” that surpassed the current clear coats was developed.
Technical Paper

Effects of Next-Generation Bio Diesel Fuel on the Engine Performance

2015-09-01
2015-01-1928
Hydrotreated Vegetable Oil (HVO) and Sugar-to-Diesel as next-generation bio diesel fuels consist of normal and iso-paraffin, and those carbon number of paraffinic hydrocarbons and distillation characteristics are narrow distribution. These characteristics would cause to deteriorate the evaporation and mixture with air and fuel. Therefore, in this study, the effects of normal paraffin (Tridecane) and iso-paraffin (HVO) on emission characteristics and cold start performance in a diesel engine were investigated by engine dynamometer tests, cold start vehicle tests, and spray analyzer tests. From the results, it was found that normal and iso-paraffin are beneficial for HC, CO, Smoke emission reduction. In addition, isomerization is effective for the diesel engine to fulfill cold start performance, since normal paraffin of narrow carbon number distribution became solidified under low temperature and high pressure condition in a common rail system.
Technical Paper

Spatio-Temporal Frequency Characteristics Measurement of Contrast Sensitivity for Smart Lighting

2016-04-05
2016-01-1420
This study aims at the development of a projection pattern that is capable of shortening the time required by a driver to perceive a pedestrian at night when a vehicle’s high beams are utilized. Our approach is based on the spatio-temporal frequency characteristics of human vision. Visual contrast sensitivity is dependent on spatiotemporal frequency, and maximum contrast sensitivity frequency varies depending on environmental luminance. Conventionally, there are several applications that utilize the spatio-temporal frequency characteristics of human vision. For example, the National Television System Committee (NTSC) television format takes into consideration low-sensitivity visual characteristics. In contrast, our approach utilizes high-sensitivity visual characteristics based on the assumption that the higher contrast sensitivity of spatio-temporal frequencies will correlate more effectively with shorter perception times.
Technical Paper

Efficient Direct Yaw Moment Control during Acceleration and Deceleration While Turning (Second Report)

2016-04-05
2016-01-1677
Electric vehicles (EVs) are attracting attention due to growing awareness of environmental issues such as fossil fuel depletion and global warming. In particular, a wide range of research has examined how direct yaw moment controls (DYCs) can enhance the handling performance of EVs equipped with multiple in-wheel motors (IWMs) or the like. Recently, this research has focused on reducing energy consumption through driving force distribution control. The first report proposed a method to minimize energy consumption through an efficient DYC for extending the cruising range of a vehicle installed with four IWMs, and described the vehicle behavior with this control. Since motors allow high design flexibility, EVs can be developed with a variety of drive systems. For this reason, various driving force distribution control methods can be considered based on the adopted system.
Technical Paper

Study on TTC Distribution when Approaching a Lead Vehicle

2016-04-05
2016-01-1452
In order to help avoid or mitigate rear-end collisions a Pre-Collision System (PCS) was developed. The purpose of this study is to clarify the Time-to-Collision (TTC) distribution when approaching a lead vehicle under normal driving condition. To enhance the effectiveness of PCS, warnings and/or automatic brake activation should happen as early as possible, however, if too early there is a high possibility of false warnings or activations, which is not desirable. If the distribution of distance to a lead vehicle under normal driving conditions is quantified, an approach limit can be estimated. In this study, we try to clarify a TTC distribution that is approximated by a log-normal distribution. Then, we investigate the Enhanced Time-to-Collision (ETTC) that is the secondary predictive value of TTC. And, we clarify the log-normal distribution of ETTC is a more stable approximator of normal driving than a log-normal distribution of TTC.
Technical Paper

Achievements and Exploitation of the AUTOSAR Development Partnership

2006-10-16
2006-21-0019
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.
Technical Paper

Development of Suspension Design Technology Applying Principal Elastic Axes

2007-04-16
2007-01-0857
Automobile manufacturers have increased the pace of vehicle development in recent years to respond to diverse market demands. Consequently, it has become crucial for manufacturers to develop new technology which enables a particular vehicle to simultaneously achieve both ride comfort and handling performance at an optimal level. This article introduces the suspension design technology applying the Principal Elastic Axes that has been developed by our company for use in its vehicles. These axes, which consist of three translational and three rotational axes, represent the set of fully decoupled stiffness axes. Applying the Principal Elastic Axes to the suspension reduces the number of design parameters, which enables suspension movements to be considered totally and simply.
Technical Paper

JCAPII Cross Check Tests of Fast Electrical Mobility Spectrometers for Evaluation of Accuracy

2007-10-29
2007-01-4081
Crosscheck tests of fast electrical mobility spectrometers, Differential Mobility Spectroscopy (DMS) and Engine Exhaust Particle Sizer(EEPS), were conducted to evaluate the accuracy of fine particle measurement. Two kinds of particles were used as test particles for the crosscheck test of instruments: particles emitted from diesel vehicles and diluted in a full dilution tunnel, and particles generated by CAST. In the steady state tests, it was confirmed that the average concentration of each instrument was within the range of ±2σ from the average concentration of all the same type of instruments. In the transient tests, it is verified that the instruments have almost equal sensitivity. For application of the fast electrical mobility spectrometers to evaluation of particle number and size distributions, it is essential to develop a calibration method using reference particle counters and sizers (CPC, SMPS, etc.) and maintenance methods appropriate for each model.
Technical Paper

Experimental Analysis of Acoustic Coupling Vibration of Wheel and Suspension Vibration on Tire Cavity Resonance

2007-05-15
2007-01-2345
It is difficult to improve tire cavity noise since the pressure of cavity resonance acts as a compelling force, and its low damping and high gain characteristics dominate the vibration of both the suspension and body. For this reason, the analysis described in this article aimed to clarify the design factors involved and to improve this phenomenon at the source. This was accomplished by investigating the acoustic coupling vibration mode of the wheel, which is the component that transmits the pressure of cavity resonance at first. In addition, the vibration characteristic of suspension was investigated also. A speaker-equipped sound pressure generator inside the tire and wheel assembly was developed and used to infer that wheel vibration under cavity resonance is a forced vibration mode with respect to the cavity resonance pressure distribution, not an eigenvalue mode, and this phenomenon may therefore be improved by optimizing the out-of-plane torsional stiffness of the disk.
Technical Paper

A SEA-Based Optimizing Approach for Sound Package Design

2003-05-05
2003-01-1556
Statistical Energy Analysis (SEA) is a promising tool for developing an efficient sound package design for reducing airborne interior noise at high frequencies. The optimal sound package, however, is not directly predicted by using the SEA vehicle model alone and therefore requires parametric studies of sound package configurations. This paper describes an effective method for using SEA modeling to achieve the desired interior noise level targets. A mathematical model, expressed by one equation, is derived on the assumption that the directions of the power flows are known in the SEA model. This equation describes the relationship between sound package properties and the resulting interior noise level. Using the relationship between weight and performance of sound package, an efficient configuration can be determined. The predicted sound pressure level of the vehicle interior with the optimized sound package correlated well to the experimental data for the case presented in this paper.
Journal Article

Development of iQ with CVT for USA

2011-04-12
2011-01-1425
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.
Journal Article

Improvement of Ride Comfort by Unsprung Negative Skyhook Damper Control Using In-Wheel Motors

2016-04-05
2016-01-1678
Vehicles equipped with in-wheel motors (IWMs) are capable of independent control of the driving force at each wheel. These vehicles can also control the motion of the sprung mass by driving force distribution using the suspension reaction force generated by IWM drive. However, one disadvantage of IWMs is an increase in unsprung mass. This has the effect of increasing vibrations in the 4 to 8 Hz range, which is reported to be uncomfortable to vehicle occupants, thereby reducing ride comfort. This research aimed to improve ride comfort through driving force control. Skyhook damper control is a typical ride comfort control method. Although this control is generally capable of reducing vibration around the resonance frequency of the sprung mass, it also has the trade-off effect of worsening vibration in the targeted mid-frequency 4 to 8 Hz range. This research aimed to improve mid-frequency vibration by identifying the cause of this adverse effect through the equations of motion.
Technical Paper

Measurement Technique of Exhaust Valve Temperature

2015-09-01
2015-01-1999
Thermal load caused by engine combustion is one of the important issues for the engines such as high-boosted downsized engines and engines with high compression ratio. In particular, it is necessary to maintain the reliability and durability of exhaust valves which are subject to the biggest thermal impact. For this reason, sodium filled hollow valves are utilized in preference to solid valves in order to decrease the exhaust valve temperature. The most common method for detecting the valve temperature is to estimate the temperature by measuring hardness on valve surface (Hardness test). However, the hardness test is only applicable to the condition up to 800°C. Therefore, this paper presents new techniques for measuring the temperature for sodium-filled valve using infrared thermography and thermocouple as an alternative hardness test. The authors also examined the valve temperatures at a variety of engine speeds and cooling of the sodium-filled valve during engine operation.
Technical Paper

Fatigue Life Prediction Method for Laser Screw Welds in Automotive Structures

2016-04-05
2016-01-0394
This paper describes the development of a fatigue life prediction method for Laser Screw Welding (LSW). Fatigue life prediction is used to assess the durability of automotive structures in the early design stages in order to shorten the vehicle development time. The LSW technology is a spot-type joining method similar to resistance spot welding (RSW), and has been developed and applied to body-inwhite structures in recent years. LSW can join metal panels even when a clearance exists between the panels. However, as a result of this favorable clearance-allowance feature of LSW, a concave shape may occur at the nugget part of the joint. These LSW geometric features, the concavity of nuggets and the clearance between panels, are thought to affect the local stiffness behavior of the joint. Therefore, while assessing the fatigue life of LSW, it is essential to estimate the influence of these factors adequately for the representation of the local stiffness behavior of the joint.
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