• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.148-154
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• 2012

Purpose: In order to improve road-friendliness of heavy vehicles, a fuzzy hybrid control strategy consisting of a hybrid control strategy and a fuzzy logic control module is proposed. The performance of the proposed strategy should be effectively evaluated using a hardware-in-the-loop (HIL) simulation model of a semi-active suspension system based on the fuzzy hybrid control strategy prior to real vehicle implementations. Methods: A hardware-in-the-loop (HIL) simulation system was synthesized by utilizing a self-developed electronic control unit (ECU), a PCI-1711 multi-functional data acquisition board as well as the previously developed quarter-car simulation model. Road-friendliness of a semi-active suspension system controlled by the proposed control strategy was simulated via the HIL system using Dynamic Load Coefficient (DLC) and Dynamic Load Stress Factor (DLSF) criteria. Results: Compared to a passive suspension, a semi-active suspension system based on the fuzzy hybrid control strategy reduced the DLC and DLSF values. Conclusions: The proposed control strategy of semi-active suspension systems can be employed to improve road-friendliness of road vehicles.

• Journal of Drive and Control
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• v.17 no.3
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• pp.47-56
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• 2020

As a shift control of automatic transmission was managed with the electronic control unit (ECU), shift quality which is a measure of shift shock during gear change has markedly improved. However, the initial clutch pressure control of the clutch filling phase should continue to rely on the predetermined control input since the input and output speeds are unchanged until the shifting process attains the inertia phase. It is critical to minimize the clutch response time and control the clutch pressure accurately at the end of clutch fill to achieve quick shift response and smoothness. Advanced transmission companies have adopted an auto calibration method which establishes the databases for the clutch piston fill-up attributes and the frictional characteristics of the disks. In this study, a distinctive auto calibration algorithm for forklift transmission under development is proposed and verified with the real-vehicle test. The experimental calibration results showed consistent turbine dynamics at the initial stage of shifts with the properly calibrated clutch-fill control parameters. By using this technique, it is necessary to finalize the shift control for the various operation conditions.

• IE interfaces
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• v.25 no.4
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• pp.393-404
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• 2012

Increasing safety requirements of automobile are asking companies to find out solutions, based on the ISO 26262 which is a functional safety standard. ISO 26262 is an adaptation of the IEC 61508 for automotive electric/electronic systems. ISO 26262 provides a V model for ECU (Electronic Control Unit) development process to secure safety against vehicle. It well describes the requirements, necessary works and their resulting products for each development phase. However, it is difficult to apply to product development for achieving functional safety in the electric/electronic systems of an automobile because it lacks explanation on the working steps to follow and the methodologies and tools to be used in each step. In this paper, we introduce the outline of the ISO 26262 product development process and present a DFSS (Design For Six Sigma) road-map based on the ISO 26262 product development process as a way to operate efficiently the ISO 26262 product development process. The DFSS road-map consists of five phases: Define, Measure, Analyze, Design, and Verify. The detailed activities, tools, inputs, and work products are given for each phase.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.2
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• pp.69-78
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• 2013

As vehicles become more intelligent for safety and convenience of drivers, in-vehicle networking systems such as controller are network (CAN) have been widely used due to increasing number of electronic control unit (ECU). Recently, FlexRay was developed to replace CAN protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. However, it is difficult for vehicle network designers to calculate platform configuration registers (PCR) and determine a base cycle or slot length of FlexRay. To assist vehicle network designers for designing FlexRay cluster, this paper presents automatic field bus exchange format (FIBEX) generation algorithm from CANdb information, which is de-facto standard database format for CAN. To design this program, structures of FIBEX, CANdb and relationship among PCR variables are analyzed.

• Journal of Magnetics
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• v.17 no.4
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• pp.285-290
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• 2012

Electric Power Steering (EPS) system is superior to conventional Hydraulic Power Steering (HPS) system in aspect of fuel economy and environmental concerns. The EPS system consists of torque sensor, electric motor, ECU (Electric Control Unit), gears and etc. Among the elements, the torque sensor is one of the core technologies of which output signal is used for main input of EPS controller. Usually, the torque sensor has used torsion bar to transform torsion angle into torque and needs linear characteristic in terms of flux variation with respect to rotation angle of permanent magnet. The torsion angle of both ends of a torsion bar is measured by a contact variable resistor. In this paper, the sensor is accurately analyzed using 3D finite element method and its characteristics with respect to four different shapes of the stator teeth are compared. The four shapes are rectangular, triangular, trapezoidal and circular type.

• IEMEK Journal of Embedded Systems and Applications
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• v.4 no.2
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• pp.84-89
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• 2009

This paper describes the development tool for applications of automotive electronic control unit based on OSEK/VDX. This development tool has a plug-in structure and is written in Java language, because of being based on Eclipse CDT. And also this development tool has another functionality of expansion, which means a special function block can be easily adopted in this development tool. Currently, this development tool consists of five blocks, which are integrated development environment block, fusing program block, system generation block, debugger block, and cross-compiler toolchain block. They have relationship between each other and work for developing OSEK/VDX-based applications. In this paper, we show the functionality of each block of this development tool and its implementation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.7
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• pp.1039-1046
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• 2001

Among the automotive steering systems, an Electric Power Assisted steering (EPAS) system utilizes an electronically controlled electric motor to provide steering assistance to the driver. The key components of the EPAS system are torque sensor, ECU (Electronic Control Unit), and DC Motor. The most important component of the EPAS is the torque sensor. The conventional torque sensor has complicated mechanical mechanism of torque detection. However, we suggest a non-contact torque sensor for EPAS using Maluss polarization law. It was found that the sensor exhibited not only excellent linearity but also superior characteristics of hysteresis, temperature and vibration.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.280-282
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• 2008

본 논문은 자동차용 능동 전륜 조향 제어 시스템을 소개한다. 능동 전륜 조향 장치는 조향의 편의성과 안정성을 위하여 조향비를 가변하거나 유사시 능동적으로 전자 제어 유닛(Electronic Control Unit : ECU)이 액추에이터를 제어해 주는 시스템이다. 최근 전자 샤시 시스템의 개발 추세인 샤시 통합 제어 관점에서 능동 전륜 조향 장치의 역할을 설정하고 성능 만족을 위한 제어기 구조에 관하여 설명한다. 설계된 제어 시스템을 3,300cc급 대형 승용차에 적용하여 그 유용성을 검증하였다.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.1
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• pp.1-5
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• 2011

The basic signals for electronic engine control are velocity and degree of the engine cam shaft. The CPS sensor used for this signal and magnetic pick-up type CPS sensor is more popular. It is very important thing analyze this signal correctly. If there are some mistakes at the analysis, like a noise, The engine do not working at the best status, it will generate some noise, emit exhaust fumes and waste more gases. In general way to analysis this signal, you use zero-level detector circuit and in order to reduce the error you must use another sensor like a TDC sensor. In this paper, We proposed the analysis method using electronics circuits for magnetic pick-up type CPS sensor. We designed Comparison level detector circuit, Differential circuit and Full-rectifier circuit for detected the Long tooth and Short tooth level correctly without another sensor. We expected it is useful for more reliable engine control.

• Tribology and Lubricants
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• v.30 no.3
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• pp.183-188
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• 2014

In this paper, we present our analysis of tribological failure examples for an anti-lock brake system(ABS) in a car. The study range of this paper is to improve the quality of ABS system by analyzing with sensor, computer, actuator and oil lines. In the first example, the brake leak from hydraulic supply line in a caliper on the rear left side of the ABS hydraulic modulator. This produces the sponge phenomenon, where the car does not brake even when the driver operates the brake pedal. The hydraulic unit operating ABS is actuator that play role regulating drive condition according with the oil pressure supplied with wheel of a car. In the second example, the service man does not completely tighten the fixed bolt after repairing the car. This causes the ABS warning lamp to light up as the ABS wheel speed sensor cannot detect whether the ABS has been activated. In the third example, the ABS electronic control unit is separated from the soldered part of the inner circuit board. Consequently, the ABS fails in control because the ABS motor pump receives no-signal for the hydraulic unit. The wheel speed sensor has to large durability because of giving signal of acting condition to computer by detected the acceleration and deceleration of wheel of a car. In the fourth example, the ABS warning lamp lights up of when cracks propagate in the circuit board soldering part. The circuit of this computer is very important part for input and output the operating signal of system. Such failures can aggravate the durability of the ABS. Thus, the ABS needs to be optimized to eliminate malfunction phenomenon.