• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.91-99
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• 2003

When the driver suddenly depresses the brake pedal under critical conditions, the desired trajectory of the vehicle can be changed. In this study, the vehicle dynamics and fuzzy logic controller are used to control the vehicle trajectory. The dynamic vehicle model consists of the engine, the rotational wheel, chassis, tires and brakes. The engine model is derived from the engine experimental data. The engine torque makes the wheel rotate and generates the angular velocity and acceleration of the wheel. The dynamic equation of the vehicle model is derived from the top-view vehicle model using Newton's second law. The Pacejka tire model formulated from the experimental data is used. The fuzzy logic controller is developed to compensate for the trajectory error of the vehicle. This fuzzy logic controller individually acts on the front right, front left, rear right and rear left brakes and regulates each brake torque. The fuzzy logic controlling each brake works to compensate for the trajectory error on the split - $\mu$ road conditions follows the desired trajectory.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.889-891
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• 2001

The eddy current brake system is one of important application of eddy current. It is adequate to obtain safe braking force in high speed transportation system and electric vehicle etc. There is a variety of configurations and materials used in manufacturing of eddy current brakes. This paper proposes the eddy current brakes which uses permanent magnet. The dynamic characteristic has been analyzed to FEM and compared with measured data.

• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.238-246
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• 2004

In displaying a virtual wall using a passive haptic device equipped with passive actuators such as electric brakes, unsmooth motion frequently occurs. This undesirable behavior is attributed to time delay due to slowness in the virtual environment update and force approximation due to the inability of a brake to generate torque in arbitrary directions. In this paper a new control scheme called direct control is proposed to achieve smooth display on the wall-following task with a passive haptic device. In direct control, brakes are controlled so that the normal component of a resultant force at the end-effector vanishes, based on the force analysis at the end-effector of the passive haptic device using the passive FME (Force Manipulability Ellipsoid). Various experiments have been conducted to verify the validity of the direct control scheme with a 2-link passive haptic system.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.381-386
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• 2000

The brake force of drum brakes for commercial vehicles is applied by a s-cam. First of all the influence of the s-cam load angles and elastic modulus of the pad on the contact pressure distribution between pad and drum was checked by using 3 dimensional finite element model. In the second part, temperature and thermal stress analyses were carried out by an axisymmetric model with constant heat flux and pressure-proportional heat flux. In the case of temperature analysis the heat conduction from the interface to the pad and the drum was modeled using a thin soft film element, so artificial division of the generated heat flux between pad and drum is not necessary. The analysis was performed by ABAQUS/Standard code.

• Journal of Auto-vehicle Safety Association
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• v.8 no.4
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• pp.18-23
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• 2016

The objective of this study is to present the inspection standards of motorcycle brake system affecting motorcycle traffic accident. The inspection standards of motorcycle brake system recommended by CITA (International Motor Vehicle Inspection Committee) are studied. The brake performance for preventing the traffic accident is assessed by the brake efficiency. Considering the KMVSS (Korean Motor Vehicle Safety Standards) and the inspection standards of CITA, United Kingdom and Japan, the brake performance in the inspection standards of motorcycle is suggested. It is recommended that the efficiency of independent front and rear brakes are 40% and 27%, respectively. It is recommended that the efficiency of combined front and rear brakes is 50%.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.889-894
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• 2001

A three dimensional transient thermo-elastic frictional contact analysis of airplane brakes is performed. The velocity history of the airplane during braking is calculated from energy conservation law. ABAQUS code is used in the analysis, and user subroutines supported in the ABAQUS are coded to calculate the frictional heat generation between pads and linings attached to back/pressure plate and rotor, respectively. Numerical results are compared with experimental ones.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.831-836
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• 2001

In the case of axisymmetric thermal analysis of drum brakes, the distribution of frictional heat produced on the interface and temperature difference between mating frictional faces are very interesting problems to computational researchers. In this paper, heat conduction from the interface to the pad and the drum was modeled by using a thin interface element, so artificial division of the generated frictional heat between pad and drum is not necessary. Temperature difference between mating frictional faces is successfully modeled by using the interface element. The influence of some parameters on tile thermal stress was checked. The analysis was performed by ABAQUS/Standard code.

• Tribology and Lubricants
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• v.15 no.2
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• pp.199-205
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• 1999

Using a coupled thermal-mechanical analysis, the thermal distortion of the ventilated disk brakes has been investigated based on the air cooling effects during 15 braking operations. The FEM results show that the bendings and distortions of the disk toward the left side are decreased, but the sinusoidal distortion of the disk rubbing surface along the arc length of the vent hole is highly increased by increasing the convective air cooling effects, which is heavily related to the squeal, wear and micro-thermal crackings at the rubbing surfaces due to uneven dissipation rates of friction heatings.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.299-304
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• 2005

A Vigilance control is a device fitted in the driving cab of a railway train to ensure that the driver is alert on the job. A simple vigilance control requires that the driver press a button at intervals not less than a certain amount and not more than another amount of time. If the driver fails to operate the vigilance control within those limits, a hooter sounds, and should the driver still doesn't operate the vigilance control then the brakes are applied. If the driver falls asleep or takes ill, then clearly such a vigilance control will sooner or later apply the brakes. The this vigilance control system which is applied to reduce the drive load at Syria diesel multiple unit train is proposed.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.173-180
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• 2001

In the case of axisymmetric thermal analysis of drum brakes, the distribution of frictional heat produced on the interface and temperature difference between mating frictional faces are very interesting problems to computational researchers. In the first part, the influence of the s-cam load angles and elastic modulus of the pad on the contact pressure distribution between pad and drum was checked by a three dimensional model. In the second part heat conduction from the interface to the pad and the drum was modeled by using a thin interface element, so artificial division of the generated frictional heat between pad and drum is not necessary. Temperature difference between mating frictional faces is successfully modeled by using the interface element. The influence of some parameters on the thermal distribution is checked. The analysis was performed by ABAQUS/Standard code.