The SAE MOBILUS platform will continue to be accessible and populated with high quality technical content during the coronavirus (COVID-19) pandemic. x

Your Selections

NIPPON SOKEN, INC.
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Technique of ECU Circuit Design Management for Automotive Ethernet

NIPPON SOKEN, INC.-Hiroyuki Mori, Miyuki Mizoguchi
Toyota Motor Corp.-Takashi Yasuda, Hideki Goto, Hiroki Keino, Kaoru Yoshida
Published 2017-03-28 by SAE International in United States
In recent years, the demand for high-speed/high-bandwidth communication for in-vehicle networks has been increasing. This is because the usage of high-resolution screens and high-performance rear seat entertainment (RSE) systems is expanding. Additionally, it is also due to the higher number of advanced driver assistance systems (ADAS) and the future introduction of autonomous driving systems. High-volume data such as high definition sensor images or obstacle information is necessary to realize these systems. Consequently, automotive Ethernet, which meets the requirements for high-speed/high-bandwidth communication, is attracting a lot of attention.The application of automotive Ethernet to in-vehicle networks requires that technology developments satisfy EMC performance requirements. In-vehicle EMC requirements consist of two parts: emission and immunity. The emission requirement is to restrict the electromagnetic noise emitted from vehicle. Therefore, automotive PHY transceivers that suppress emission noise have been developed and are available on the market. The immunity requirement is resistance against electromagnetic radiation from inside or outside the vehicle. It is commonly known that immunity performance decreases when the impedance characteristics of the transmission lines are unbalanced. In the…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Capacitive Humidity Sensors Using Highly Durable Polyimide Membrane

SAE International Journal of Passenger Cars - Electronic and Electrical Systems

NIPPON SOKEN, INC.-Toshiki Isogai
DENSO Corporation-Naohisa Niimi, Takahiko Yoshida
  • Journal Article
  • 2013-01-1337
Published 2013-04-08 by SAE International in United States
Humidity sensors used in automatic windshield defogging controls contribute to the improvement of fuel consumption. The optimum control of air conditioning systems can be realized by adding humidity information to conventional systems which have used only temperature information.While resistive humidity sensors have been widely used, their sensing range and responsiveness are observed as issues. Resistive sensors cannot function at a humidity range of around 100% RH as well as at a low temperature range, and have a low response rate to sudden changes in humidity. It is considered that resistive humidity sensors will be replaced with capacitive ones which have a wide sensing range and high responsiveness. However, since capacitive sensors use macromolecule organic materials for their humidity sensing membranes, characteristic changes caused by two factors in a high temperature and high humidity environment are concerns: the deterioration of the membrane itself, and the decrease of the adhesive strength between the membrane and the underlying layers.This paper describes a newly developed capacitive humidity sensor with high durability by suppressing hydrolysis and swelling of membranes which…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Visualization of the PM Deposition and Oxidation Behavior Inside the DPF Wall

NIPPON SOKEN, INC.-Shigeki Daido
Toyota Motor Corp.-Nobuyuki Takagi
Published 2009-04-20 by SAE International in United States
We investigated filtration and oxidation behavior of secondary particle of particulate matter (PM) in the diesel particulate filter (DPF) wall using a newly developed visualization technique. The observations from magnified cross section view of the test piece cut out from full sized DPF made of Cordierite DPF and SiC. DPF. Only in the beginning of the filtration process, the PM penetrates into deep inside of the DPF wall. And in the PM forced oxidation process, the PM in the wall was oxidized first, then the PM cake layer on the DPF wall thinner by oxidized from contact part with the DPF wall. We carried out these observations with the SiC DPF. Further, we have tried to estimate the activation energy of the PM oxidation from the shrinking form of accumulated secondary particles of PM inside of the cordierite DPF loaded by platinum (Pt). We confirmed that the experimented value of the activation energy is close to that of former researchers.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of Reduction Method for Whirl Noise on Turbocharger

NIPPON SOKEN, INC.-Kouzi Ohara
Toyota Central R&D Labs., INC.-Mizuho Inagaki
Published 2007-10-29 by SAE International in United States
The whirl noise on turbochargers is generated by the self-induced vibration of the oil film in the bearing system. The noise is characterized by its frequency behavior that doesn't increase proportionately to the turbo shaft speed. It tends to be felt annoying. In this paper, to improve the whirl vibration, a statistical analysis approach was applied to the bearing specifications. The results from experiments showed that the bearing clearances played an important role in the reduction of the whirl vibration. To further investigate into this phenomenon, the shaft oscillation behavior was measured. And a vibration simulation program for the turbocharger bearing system was also developed. As the results, it was concluded that suppressing the shaft oscillation with a parallel mode could reduce the whirl vibration and the ‘different-clearance’ combination, in which the different bearing clearance specification was applied to the compressor and turbine side, could reduce the whirl vibration further than the conventional ‘same-clearance’ bearing set.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Prediction of Engine Oil Aeration Rate

NIPPON SOKEN, INC.-Takumi Kataoka, Yuusuke Kimura
TOYOTA MOTOR CORP.-Katsuaki Takahashi, Takashi Kikuchi, Naoya Okada
  • Technical Paper
  • 2007-08-0600
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
According to progress of engine performance for passenger car, large quantity oil circulates in engine internal narrow space. It causes some oil foaming and aeration problems. In this study, we have developed a prediction method of engine oil aeration rate from engine specifications and running conditions. It was realized from engine test that oil aeration was stable between aeration and bubble release from oil surface. As bubble size effects on bubble release rate from oil surface, this prediction method calculates aeration rate from evaluation of bubble number and bubble size.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Oxygen Concentration and Temperature Behavior on Three-Way Catalyst

NIPPON SOKEN, INC.-Yoshitada Kodama, Nobuo Imatake
TOYOTA MOTOR CORP.-Takahiko Fujiwara
  • Technical Paper
  • 2007-08-0720
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
In order to measure the temperature of the catalyst-coated layer and local oxygen concentration inside the catalyst accurately, we developed a catalyst-coated thermocouple and a micro-size oxygen sensor. Using those two sensors, it became clear that oxygen storage phenomena of the three-way catalyst (TWC) mainly affect the temperature rise of the catalyst under fuel cut condition.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Automatic Parking System With Safety Confirmation Support

NIPPON SOKEN, INC.-Takenori Matsue, Masayuki Imanishi
Kobe Univ.-Takanori Fukao
  • Technical Paper
  • 2007-08-0495
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
The vehicle control with K-turn and an instantaneous confirmation system in the blind spot are required for parking in tight quarters. In this research, we developed an automatic parking system with vehicle control with K-turn using lidar information and quick-and-easy safety confirmation system by zooming dangerous zones with camera display.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Relation Between pH of Gasoline Engine Oil and Wear of Cylinder Wall

NIPPON SOKEN, INC.-Kiyonari Kojima, Hisanaga Matsuoka
DENSO CORP.-Kazuyuki Horie, Tetsuo Hariu
  • Technical Paper
  • 2007-08-0601
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
We investigated the relation between the pH of the gasoline engine oil and the amount of wear of the cylinder wall material. The amount of wear begins to increase under pH4. This cause is generation of the corrosion film of the cylinder wall material and fragility of the film. Therefore, the management of the pH is effective to the prevention of the wear of the cylinder wall.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Combustion Improvement of an HSDI Diesel Engine With Increasing Injection-Pressure and Injection Rate Shaping

NIPPON SOKEN, INC.-Hirokuni Tomita
DENSO CORP.-Yoshihisa Yamamoto
  • Technical Paper
  • 2007-08-0532
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
Effects of high-injection pressure up to 240 MPa and injection-rate shaping on rating power and its revolution, and on exhaust emissions from an HSDI diesel were investigated using single-cylinder research engine. Fuel-air equivalent ratio (φ) limited by exhaust smoke number is strongly associated with velocity ratio of fuel spray to squish air motion. It is confirmed high injection pressure of 240 MPa realizes φ0.78 at 5000 rpm. Effect of initial injection-rate suppression on exhaust emission decreases as charging efficiency is increased. High injection pressure over 200 MPa is also effective on reduction of NOx and smoke with combination of high-boost pressure and high-EGR ratio.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study of Rising Thermal Efficiency Using an Argon Circulated Hydrogen Engine

NIPPON SOKEN, INC.-Toru Kosuda, Osamu Fujishiro
TOYOTA MOTOR CORP.-Shinichi Mitani, Daisaku Sawada
  • Technical Paper
  • 2007-08-0503
Published 2007-10-01 by Society of Automotive Engineers of Japan in Japan
One of the determining factors of internal combustion engine thermal efficiency is the operating gas specific heat ratio. Upon this, argon, which holds the premier specific heat ratio, is introduced in the operating gas, circulating through the cycle. Hydrogen and oxygen are supplied as a source of combustion; water formed through the combustion is condensed and exhausted. A limit in the thermal efficiency of a reciprocating engine was researched. To implement combustion, direct injection of hydrogen into the combustion chamber and self-ignited diffusive combustion are effective. A prototype open cycle engine, which demonstrates this principle, performed 54% indicated thermal efficiency.