• 한국자동차공학회논문집
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• 제21권1호
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• pp.78-85
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• 2013

This paper presents the sliding mode control methods for anti-lock brake system (ABS) with the friction force observer. Using a simplified quarter car model, the sliding mode controller for ABS is designed to track the desired wheel slip ratio. Here, new method to find the desired wheel slip ratio which produces the maximum friction force between road and tire is suggested. The desired wheel slip ratio is varying according road and tire conditions to produce maximum friction force. In order to find optimum desired wheel slip ratio, the sliding mode observer for friction force is used. The proposed sliding mode controller with observer is evaluated in simulation, and the control design is shown to have high performance on roads with constant and varying adhesion coefficients.

• 한국자동차공학회논문집
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• 제15권6호
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• pp.120-127
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• 2007

This paper describes the development of a nonlinear observer for four wheel steer (4WS) vehicle. An observer is designed to estimate the vehicle variables difficult to measure directly. A brake yaw motion controller (BYMC), which uses a PID control method, is also proposed for controlling the brake pressure of the rear and inner wheels to enhance lateral stability. It induces the yaw rate to track the reference yaw rate, and it reduces a slip angle on a slippery road. The braking and steering performances of the anti-lock brake system (ABS) and BYMC are evaluated for various driving conditions, including straight, J-turn, and sinusoidal maneuvers. The simulation results show that developed ABS reduces the stopping distance and increases the longitudinal stability. The observer estimates velocity, slip angle, and yaw rate of 4WS vehicle very well. The results also reveal that the BYMC improves vehicle lateral stability and controllability when various steering inputs are applied.

• 한국항공운항학회지
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• 제25권2호
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• pp.18-24
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• 2017

Results of the experimental research are described in this thesis, which are about braking characteristics of aircraft ABS brake system with different ground conditions. Dynamo-tests were conducted with the state of the application aircraft condition and with two different ground conditions. The Braking characteristics on each ground condition were drawn from the results of occurrence of skid, braking distance and deceleration. The braking performance of the application aircraft could be anticipated and the efficient range of braking operation could be set with those results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.523-530
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• 2005

This paper addresses sliding mode control (SMC) of the anti-lock braking system (ABS) with a compensator of model uncertainties such as vehicle parameter variation, unmodeled dynamics, and external disturbances. A sliding mode controller (SMC) is designed with a nominal vehicle model to achieve a desired wheel slip ratio. A disturbance observer (DOB) is introduced to compensate the model uncertainties and is designed with a transfer function of a hydraulic brake dynamics. Through simulations on the model uncertainties, it is verified that the sliding mode control with the DOB can give the simulation results better than the sliding mode control without the DOB.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.166.1-166
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• 2001

Anti-lock Braking System(ABS) is a device which prevents the wheels form locked up under emergency braking of a vehicle. So it helps the vehicle to maintain the steerability and shortens the braking distance by maintaining optimal frictional force during braking since the tire road slip is controlled in acceptable range. Recently, ABS is accepted as a standard equipment in vehicles, especially in commercial vehicles(bus and trucks). Commercial vehicles don´t use hydraulic lines but use pneumatic lines for braking system mostly. In this paper, ECU(Electronic Control Unit) for the anti-lock braking system of a commercial vehicle which is equipped with a full-air brake system and its control algorithms are presented. In this algorithm wheel speed acceleration flags and wheel slip flags are defined ...

• 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.

• 한국자동차공학회논문집
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• 제7권8호
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• pp.172-179
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• 1999

This paper presents a simple but effective DYC algorithm which enhances vehicle lateral stability by using an anti=lock brake system (ABS). In the proposed algorithm, only the front outer wheel is controlled during cornering maneuver instead of controlling all four wheels because the wheel has the largest role in DYC and it is easy and simple to control the only one wheel. An ABS Hardware - In -The -Loop Simulation ( HILS) system that may be used to realistically test real vehicle dynamic behavior in a lab is used for evaluating the proposed DYC algorithm in severe situations where a vehicle is destabilized without DYC . The HILS results show that the proposed DYC algorithm has the potential of maintaining vehicle stability in some dangerous situations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 D
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• pp.612-614
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• 2000

ABS(Anti-lock Braking System) is a device which prevents the lock-up of car wheels during emergency braking. It helps to maintain the steerability since the tire-road slip is controlled in an acceptable range. By maintaining the maximal frictional force during braking. ABS can reduce the braking distance. Recently, ABS is accepted as a standard equipment in vehicles, especially in commercial vehicles(bus and trucks). Commercial vehicles mostly use pneumatic pressure for braking. In this paper, ECU(Electronic Control Unit) for the anti-lock braking system of a commercial vehicle which is equipped with a full-air brake system and its control algorithms are presented.

• 한국자동차공학회논문집
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• 제16권3호
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• pp.52-59
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• 2008

Most accident reconstruction or analysis depend on the coefficient of friction to estimate the vehicle speeds. Skid mark and coefficient of friction are usually utilized to calculate the velocity and behavior of vehicles. For a critical case such as traffic accident reconstruction, however, the initial velocity of the car should be calculated precisely. In this paper, emergency brake tests on ABS and Non-ABS brake system are conducted on the dry pavement asphalt road on speed 40, 60, 80 and 100 km/h respectively. The SWIFT sensor was established in the front wheel and rear wheel at driver side to measure the forces, moments and speeds of revolution of the tires. These tests results can be available to brake tests and accident reconstruction.

• 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.