• Journal of Institute of Control, Robotics and Systems
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• v.7 no.5
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• pp.432-437
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• 2001

Korea High Speed Train(KHST) is supposed to run up 350km/h, in which the braking system has a crucial role for the safety of the train. In the design st데 of the braking system, its very hard to ac-quire information data for design guidelines. A HILS(Hardware-In-the-Loop Simulation) system can be used to get design data which could simulate the braking system of the real train in real-time. In this paper, cars are modelled including car dynamics, brake blending algorithms, pneumatic actuator dynamics, the models of each braking devices, adhesive coefficients, and soon. Real-time braking time, distance, and other design parameters are simulated using a DSP board and C language which shows the validity of the proposed method.

• Proceedings of the KIEE Conference
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• 2000.11d
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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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.5
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• pp.517-523
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• 2004

Recently, wheel slip controllers with controlling the wheel slip directly has been studied using the brake-by-wire actuator. The wheel slip controller is able to control the braking force more accurately and can be adapted to various different vehicles more easily than the conventional ABS systems. The wheel slip controller requires the information about the tire braking force and road condition in order to achieve the control performance. In this paper, the tire braking forces are estimated considering the variation of the friction between brake pad and disk due to aging of the brake, moisture on the contact area or heating. In addition, the road friction coefficient is estimated without using tire models. The estimated performance of tire braking forces and the road friction coefficient is evaluated in simulations.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1083-1084
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• 2008

This paper proposes the design of anti-braking system on aircraft and wheel slip ratio control using adaptive slide mode control. By maintaining the desired wheel slip ratio under runway conditions, we can obtain the maximal frictional force and reduce the braking range. In this paper, we apply an adaptive sliding mode control to aircraft brake system and it can guarantee the robustness under variations in brake characteristics. The performance of proposed controller is verified in simulations.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1916-1921
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• 2008

In the braking process of rolling stocks, the equivalent braking force is applied to the all bogies. However, the load applied to the front and rear bogie are different in the actual commercial traveling. In the case, since the different slip situation is occurred in each bogie, it is essential to use the independent anti-slip control per bogie unit in order to reduce the loss of braking force. In this paper, the algorithm about bogie unit braking is proposed and verified.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.294-299
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• 2006

Korean high speed train(HSR-350x) has adopted a combined electrical and mechanical(friction) braking system. Brake blending control unit(BBCU) controls each brake system to fulfill the required brake performances such as braking distance, deceleration and jerk. When the disc brake is applied in the high speed region, the wear of pad is increased rapidly. In this paper, we discuss the optimized patterns of the disc brake force from the view point of braking energy.

• Journal of Drive and Control
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• v.16 no.3
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• pp.23-32
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• 2019

This study proposed a fault tolerant control algorithm for electro-hydraulic brake systems where permanent magnet synchronous motor (PMSM) drive is adopted to boost the braking pressure. To cope with motor position sensor faults in the PMSM drive, a braking pressure controller based on an open-loop speed control method for the PMSM was proposed. The magnitude of the current vector was determined from the target braking pressure, and motor rotational speed was derived from the pressure control error to build up the braking pressure. The position offset of the pump piston resulting from a leak in the hydraulic system is also compensated for using the open-loop speed control by moving the piston backward until it is blocked at the end of stroke position. The performance and stability of the proposed controller were experimentally verified. According to the results, the control algorithm can be utilized as an effective means of degraded control for electro-hydraulic brake systems in the case that a motor position sensor fault occurs.

• Journal of the Korean Solar Energy Society
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• v.30 no.4
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• pp.1-8
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• 2010

The mechanical parts of small windp ower generator less than 10kW are manufactured in the form of removing most of the accelerators. The braking system to protect blade from damages caused by high wind speed is manufactured in a manner having apparatus system(furling), manual brake or no brake. This study is on braking system in small size wind power generator, and carried out survey as following steps by applying electric braking system which uses armature reaction. We explained the principle of electric braking system and the principle of existing braking system. Also, this paper interpreted short circuit current through open circuit and short circuit, as well as checking brake system's action using armature reaction with real construction of control device.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.525-533
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• 1998

A conventional contact type brake system which uses a hydraulic system has mny Problems such as time delay response due to pressure build-up, brake pad wear due to contact movement, bulky size, and low braking performance in high speed region. As vehicle speed increases, a more powerful brake system is required to ensure vehicle safety and reliability. In this work, a contactless brake system of an eddy current type is proposed to overcome problems. Optimal torque control which minimizes a braking distance is investigated with a scaled-down model of an eddy current type brake. It is possible to realize optimal torque control when a maximum friction coefficient (or desired slip ratio) corresponding to road condition is maintained. Braking force analysis for a scaled-down model is done theoretically and experimentally compensated. To accomplish optimal torque control of an eddy current type brake system, a sliding mode control technique which is, one of the robust nonlinear control technique is developed. Robustness of the sliding mode controller is verified by investigating the braking performance when friction coefficient is varied. Simulation and experimental results will be presented to show that it has superior performance compared to the conventional method.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.67.4-67
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• 2002

Antilock brake System (ABS) is a essential safety equipment for modern vehicles. It prevents wheels from being locked-up when emergency braking of a vehicle is required. So it can improves directional stability of the vehicle, shortens stopping distance. Heavy Vehicles such as trucks and buses use mainly pneumatic pressures for their braking systems, where pneumatic modulators control the flow rate of compressed air thus braking pressures in the wheels. In this paper, a antilock braking algorithm which is suitable for heavy vehicles was developed. This algorithm uses limit cycle of wheels and is implemented in the ABS ECU. The developed algorithm and ECU were tested in the labo..