• 한국자동차공학회논문집
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• 제9권4호
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• pp.121-130
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• 2001

For the purpose of optimal control of anti-lock brake systems, precise dynamic characteristics analysis of hydraulic modulator, especially solenoid valve is necessary. However, most of researches so far have dealt with dynamic characteristic analysis of valve itself, and the results have been restrictively applied to the actual ABS modulator, where hydraulic pressure is acting. In this study, mathmatical modeling and experimental analysis were peformed in order to evaluate the valve dynamic characteristics when the hydraulic pressure is applied. High pressure on the master cylinder that affects on the valve dynamic characteristics have been analyzed quantitatively, and performance improvement methods have been suggested through parameter study. Consequently, results of solenoid valve dynamic characteristics analysis derived in the study can be utilized as criteria for the optimal control of anti-lock brake systems.

• 전기학회논문지
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• 제59권11호
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• pp.2083-2088
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• 2010

It is necessary to carry out quantitative analysis for the ABS hydraulic modulator to upgrade the system performances. Mathematical modeling method for the ABS hydraulic modulator, is suggested in the view of electromagnetism and fluid mechanics. Also, an analytic method is proposed for the resultant forces of electromagnetism and hydraulic pressure generated in the real vehicle ABS. The relationships between the design factor of Inlet & outlet solenoid valve and the system performance of ABS, are investigated through the analytical precess.

• 한국화재소방학회논문지
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• 제33권3호
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• pp.121-127
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• 2019

본 논문에서는 자동차 ABS 모듈의 결함으로 인한 화재사고에 대하여 기술하였다. 최근 발생한 화재 사례 중 동일 제조사의 ABS 모듈을 적용하는 다수의 차량에서 유사한 결함으로 인해 화재가 발생하는 경향을 나타내었다. 앞서 언급한 ABS 모듈에서는 배터리를 통해 상시전원으로 공급되는 전원배선 사이에서 절연파괴가 발생되는 특징을 나타내는데 이러한 부분은 연소 확대 과정에서 외부 화염에 의해 형성되기 어려운 부분으로 ABS 모듈 자체의 결함으로 판단된다. 본 연구의 결과로 부터 특정 제조사에서 생산 판매되는 차량에 대한 화재원인 조사에 있어서는 반드시 ABS 모듈의 결함 여부에 대한 조사가 필수적으로 진행되어야 할 것이다.

• 전력전자학회논문지
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• 제15권4호
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• pp.335-341
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• 2010

전기제동 시스템(Electric braking system)은 기존 자동차 시스템에서 사용된 유압 브레이크를 대신하여 전동기를 이용하여 제동력을 얻게 된다. 전기제동은 기존 유압식에 비해 부품의 수가 감소되며 ABS, ESC 등의 응답성 향상 및 제동거리 감소효과를 얻을 수 있다. 본 논문에서는 EMB(Electro-Magnetic Brake)용 BLAC 전동기의 제어기를 개발하였다. 제어 시스템은 BLAC 전동기 구동을 위한 전력변환장치와 속도제어를 위한 디지털제어기로 구성되었으며, 빠른 토크 응답특성을 위해 벡터제어 기법을 적용하였다. 또한 Matlab/Simulink를 이용한 시뮬레이션 및 실험 결과를 제시하여 EMB용 BLAC 전동기의 성능을 검증하였다.

• 한국자동차공학회논문집
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• 제9권2호
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• pp.152-167
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• 2001

Recently safety systems for the commercial vehicle have been rapidly developed. However, we still have many problems in the vehicle stability and the braking performance. Especially, a commercial vehicle may meet a dangerous braking condition when the vehicle is lightly loaded or empty and when the road is wet or slippery. Under these conditions, the truck can spin out or the tractor can jackknife or the trailer can swing out. To design the air brake system for the commercial vehicle, since the air brake system has many design variables, there must have been intensive researches on a method how to prevent dynamic instability and how to maximize the vehicle deceleration. In this study, mathematical models about the tractor-semitrailer and the air brake system including an ABS controller have been constructed for computer simulation. Also, simple examples are applied to show the usefulness of the program. Designers can use this simulation program for understanding the braking characteristics such as trajectory, braking distance, longitudinal deceleration, lateral deceleration, and yaw rate on various road conditions.

• 대한기계학회논문집A
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• 제28권8호
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• pp.1125-1134
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• 2004

This paper presents a mathematical model which is about the dynamics of not only a two wheel steering vehicle but a four wheel steering vehicle. A sliding mode ABS control strategy and PID rear wheel control logic are developed to improve the brake and cornering performances, and enhance the stability during emergency maneuvers. The performances of the controllers are evaluated under the various driving road conditions and driving situations. The numerical study shows that the proposed full car model is sufficient to accurately predict the vehicle response. The proposed ABS controller reduces the stopping distance and increases the vehicle stability. The results also prove that the ABS controller can be employed to a four wheel steering vehicle and improves its performance. The four wheel steering vehicle with PID rear wheel controller shows increase of stability when a vehicle speed is high and sharp cornering maneuver when a vehicle speed is low compared to that of a two wheel steer vehicle.

• International Journal of Internet, Broadcasting and Communication
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• 제12권4호
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• pp.71-82
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• 2020

Traffic accidents due to excessive speed frequently occur in places where traffic signal controllers are installed, places where sharp curves exist, or places where the traffic signal cycle does not match the current time. These traffic accidents cause economic loss due to the destruction of road facilities and structures, and cause a big problem of increasing the number of traffic accident deaths. When a traffic accident occurs, leaving a tire mark before or after a car crash, pre-collision speed of the car is calculated using the law of conservation of momentum or the skid mark formula. In the skip skid mark generated in ABS brake vehicles and the combshaped yaw mark generated by tire trace caused by lateral sliding, there is a difference of 30-40% in the reliability of the vehicle speed calculated by the smite mark. In this paper, we propose an algorithm that can improve the calculation reliability in vehicle speed by using skid marks in order to compensate for this problem. In addition, we present an intelligent speed calculation algorithm for traffic safety and a computer simulation in order to prevent traffic accidents by estimating the speed of a vehicle, using Skid marks, Yaw marks, and ABS brake characteristics and fuzzy rules.

• International Journal of Automotive Technology
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• 제6권1호
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• pp.37-44
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• 2005

The creation of automotive systems of active safety with intelligent functions needs the use of new control principles for the wheel and automobile. One of such directions is the pre-extreme control strategy. Its aim is the ensuring of wheel's work in pre-extreme, stable area of tire grip wheel slip dependence. The simplest realization of pre-extreme control in automotive anti-lock brake systems consists in the threshold and gradient algorithms. A comparative analysis of these algorithms, which has been made on 'hardware in-the-loop' simulation results of the braking for bus with various anti-lock brake systems (ABS), indicated their high efficiency.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1608-1611
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• 2004

Anti-lock brake systems (ABS) are being increasingly used in a wide range of applications due to safety. This paper deals with a high performance optimal sliding mode controller for slip-ratio control in the ABS. In this approach a sliding surface square is considered as an appropriate cost function. The optimum brake torque as a system input is determined by minimizing the cost function and used in the controller. Simulation results reveal the effectiveness of the proposed sliding mode controller.

• 한국자동차공학회논문집
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• 제7권9호
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• pp.146-157
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• 1999

Safety systems for road vehicles have been rapidly developed in recent years. Especially, the VDC(Vehicle dynamics Control) system is a new active safety system for road vehicles which controls its dynamic vehicle motion in emergency situations . In the case of configuring the VDC system by utilizing the ABS(Anti-lock Brake System), the role of a control logic which directly influences the vehicle motion is very important. In this study the performance of the VDC vehicle was compared to the performances of the CBS (Conventional Brake system )and ABS vehicle. For various driving conditions , the simulation of vehicle dynamics with known VDC control logics was performed. Analysis results showed the VDC vehicle could stably perform even on the road of low coefficient of friction. In addition it was shown that the basic control logic for the VDC system could outstandingly improve driving stability in the case of braking as well as constant speed cruising.