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Recently, as a automobile becomes more electronic and intelligent, MEMS(Micro Electro Mechanical System) sensors lead the technology and market of automotive sensor by overcome limitation of size, accuracy and reliability of mechanical sensors. Accelerometer, gyro, and pressure sensor are mainly studied MEMS sensor in the automobile field. Specially, intensification of safety regulation has increased the requirement and interest of the accelerometer. There are piezoelectric, piezoresistive, capacitive type in the sensing method of the accelerometer. Among these, piezoelectric method has high sensitivity feature with a simple manufacturing process. In this paper, we fabricated Flexural Plate Wave(FPW) accelerometer which sense frequency change of the vibrating piezoplate and found a optimum condition of the piezoplate shape and manufacturing condition to improve performances by using the design of experiment.

This paper describes our verification work for multi-axes sensing MEMS accelerometers of comb shaped structure for electronic stability control (ESC) system. The results of basic, environmental performance test and durability test using simulation, it proved that comb structure has same performance and durability with cantilever structure. And we can also find there is no difference between single axis and multi-axes sensing accelerometer’s performance. The multi-axes sensing MEMS accelerometers of comb structure can reduce costs and increase the space efficiency of the advanced ESC system

This paper reports the findings of the effect that different friction materials have on the amount of groan noise in the automotive braking system. In order to investigate the pad material's influence on groan noise, a comparison analysis was carried between pads for which a groan noise did occur and pads for which a groan noise did not occur. The comparison analysis results showed that the groan noise was affected by the pad's raw material particle size. It was found that the pad's raw material particle size affected the change in the pad's surface condition. Changed pad surface conditions are related to groan noise. In addition, the friction coefficient (or friction force) for different pad materials was investigated to ascertain the relationship between groan noise and the friction coefficient (or friction force).

A 40MFLOPs DSP(Digital Signal Processing) based data acquisition and engine control system with 2-microprocessors (one for DSP, the other for host computer) has been developed for the rapid acquisition of analog data from an engine with ECU. With the use of a DSP system, it has been demonstrated that high speed data acquisition by 8 channels (0.8MHz/CH) as well as real time display and real time processing of various thermodynamic & knocking analyses are successfully performed. The engine operating conditions are to be changed through a serial communication interface, and performance of an engine can be analyzed as a function of time or crank angle. As a result, the correlations between engine performance and various engine operating conditions can be obtained with high speed and ease.

The effects of swirl on early flame development and late combustion characteristic were investigated using a high-speed single-shot visualized SI engine. LDV measurements were performed to obtain a better understanding of the flow field in this combustion chamber. Spark plugs were located at half-radius (R/2) and center of bore. High-speed Schlieren photographs at 20,000, frames/sec were taken to visualize the detailed formation and development of the flame kernel with cylinder pressure measurements. This study showed that high swirl favorably affected combustion-related performances in terms of the maximum cylinder pressure and flame growth rate regardless of spark position. However, at R/2 ignition the low swirl showed desirable effects at low engine speed, and degraded performance as engine speed increased than without swirl. The effects of spark plug shapes and rotations on combustion performances at R/2 ignition and swirl were found.

Recently, with advantages in weight, noise, and cost, plastic gears are fast replacing current metal gears, and gradually expanding their scope of application. Despite such advantages however, plastic gears have been limited in their application due to their relatively low performance levels in the areas of strength, abrasion, and friction. In general, the addition of lubricants significantly improves its frictional properties. Such improvements, however, are often accompanied by deteriorating mechanical properties,. Therefore, the amount of lubricant added needs to be properly controlled. In this research project, we composed GF-reinforced nylon resins of various compositions, tested the resins for mechanical, frictional, and wear properties, and tested and analyzed the synergy between the lubricants.

Recently, to enhance passenger comfort, air suspension systems with rubber tube have been replacing conventional coiled spring type suspension in automobile suspension systems. In this study, the optimum design of rubber and cord materials in rubber tube, aimed at improving the performance of the air suspension system, has been studied. To determine the optimum design, the study altered the fillers and antioxidants in CR (chloroprene rubber) compounds with good ozone-resistance properties, and changed the angles and thickness of the nylon cord. The study produced rubber tubes using cord-reinforced rubber composite materials, then analyzed and measured the resultant physical properties, microstructure, and dimensions. It also evaluated the load capacity, static and dynamic spring characteristics, outer diameter changes, and pressure changes in the loading, and determined the burst pressure of air suspension.