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Journal Article
Long Xie, Masaru Yamasaki, Toshiyuki Ajima, Junnosuke Nakatsugawa, Yoshitaka Sugiyama
Electric power steering system has been widely used in passenger cars to replace hydraulic power steering system. In this paper, a coupled system simulator for dual-pinion electric power steering system is developed and its dynamics is verified using experimental data. The mechanical subsystem model is developed using mass, spring-damper and experimental data with hysteresis characteristic. For the control subsystem, the controller model is developed by transplanting control program from the controller in real vehicle to the simulator. For the electric subsystem, the motor model is developed using the map of current to torque which is created by magnetic field analysis in advance. The three subsystems are combined to form the complete system simulator and numerical simulation is performed. The simulation results are compared to the experimental data and the error is less than 10%.
Technical Paper
Shiro Yamaoka, Hiromu Kakuya, Shinji Nakagawa, Takashi Okada, Atsushi Shimada, Yusuke Kihara
In this study, the possibility of real-time HCCI control in a multi-cylinder gasoline engine was examined. Specifically, we applied a multivariate analysis based on an experimental design of quality engineering, and picked out several engine parameters which influence gasoline HCCI combustion stability. We clarified the characteristics of engine parameters in a gasoline HCCI operation area and propose the control concept: The internal EGR control is applied to multi-cylinder control by using the variable valve system, and air-fuel mixture control is applied to each-cylinder injection control while keeping the mixture homogeneous. Combustion conditions and engine out A/F need to be detected and fed back individually for each cylinder. With the proposed concept, it is possible to construct a real-time HCCI control system in a multi-cylinder gasoline engine.
Technical Paper
Toshimichi Minowa, Ken'ichirou Kurata, Hiroshi Kuroiwa, Masahiko Ibamoto, Masami Shida
An automotive powertrain control system using only one signal of the output shaft speed sensor has been investigated in order to lower the system costs and to simplify the calibration process A new smooth torque method after downshifting is described which is based on the differential value of automatic transmission output shaft speed The starting time of the engine torque control for restraining the torque fluctuation after downshifting can be detected accurately as a result of using the differential value The proposed engine torque control method is advantageous since it simplifies the calibration process for the data tables Moreover, it is possible to lower the cost of parts used in the automatic transmission control since speed and torque sensors are unnecessary The smooth torque control method was examined using a test vehicle and the same smooth torque after downshifting was obtained when the new method was employed
Technical Paper
Yoshishige Ohyama, Minoru Ohsuga, Mamoru Fujieda
The relationships between air flow metering and combustion control for spark ignition engines, such as engines with three way catalysts, lean NOx catalysts, two stroke engines and direct fuel injection engines were investigated. The effects of control parameters on combustion were analysed and the relationships between control parameters and air flow metering and roles of the meters in combustion control were clarified. The control strategies adaptable to many types of engines which have a wide control range of the air/fuel mass ratio are classified as (1) air quantity control,(2) fuel quantity control, and (3) exhaust gas recycle quantity control. The control parameters for the three strategies are fuel quantity, air quantity, exhaust gas recycle quantity, exhaust gas temperature, knocking, excess air factor, and mixture quality with additional parameters of swirl ratio, and spark timing for conventional spark ignition engines, two stroke engines and direct injection engines.
Technical Paper
Toshlharu Nogl, Yoshishige Ohyama, Teruo Yamauchi
Effects of mixture formation of fuel injection systems on gasoline engine performance have been studied. Several fuel injectors which produced various spray diameters and spray patterns were used in engine tests. Spray behavior in an air flow was investigated to clarify the spray distribution through the intake valve. The relationships between the spray distribution near the intake valve and the HC emission or engine response were considered. The amount of HC emissions increased if fuel was injected when the intake valve was open with a heavy load (e.g. an engine speed of 2000 rpm and a manifold pressure of 98 kPa), because fuel would flow into the cylinders one-sidedly, causing a liquid film to form. The amount of HC emissions also increased if fuel was injected when the intake valve was open with a light load (e.g. during idling), because the fuel injection pulse would be short and fuel would flow into the cylinders, but the air-fuel mixing would not be enough to cause a misfire.
Technical Paper
K. Toriyama, T. Ishibashi, M. Kohyama, T. Takemoto
A liquid-crystal display using the twisted nematic mode was developed for an automotive instrument panel. A low viscosity, quick response liquid crystal of wide nematic range (−30 to 85°C) was designed with the aid of the molecular theory for viscosity of liquid crystals. A liquid crystal less than 20 cp at 25°C with wide mesomorphic range (−30 to 85°C) was developed. A display with this material gave quick response, about one and one-half seconds at −30°C. For the most uniform response and widest viewing angle, a liquid crystal molecular alignment of low tilt angle was developed. A simple rubbing alignment technique was used which is compatible to glass sealing. A polarizer resistive to high temperature and high humidity was applied. The display can be operated with good performance and high reliability.
Viewing 1 to 6 of 6