• Proceedings of the KSR Conference
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• 2000.05a
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• pp.218-225
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• 2000

Recently, right rail transit (L.R.T.) systems become influential as a new traffic system in urban area to solve heavy traffic problems. However, there are little research results about the dynamic interaction problems between the vehicle and structural system, even though some studies far those static problems have been carried out. Therefore, first of ail, the dynamic equations of an interaction between vehicle system and surface roughness of the vehicle path are derived before developing the dynamic equations of vehicle-structure-surface roughness system, in this study. As a vehicle model, an automated guide-way transit (A.G.T.) system is adopted. Parametric study shows that the dynamic wheel loads of the vehicle system has a tendency to increase with vehicle speeds and stiffness of suspension system. However, those dynamic wheel loads have tendencies to decrease in according to loads of the vehicle system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.600-605
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• 2011

This paper shows field test and evaluation results for a wireless vehicle detector with anisotropic magneto-resistive (AMR) sensors. The detector consists of two AMR sensors and mechanical and electronic apparatuses. The AMR sensor senses disturbance of the earth magnetic field caused by a vehicle moving over the sensor and then produces an output indicative of the moving vehicle. In this paper, vehicle speeds are calculated by using two AMR sensors fixed on a board, with constant distance. To test and evaluate the accuracy of the detector in real traffic situations, the detector was installed on a local highway and vehicle speeds and volumes were measured both in a free running and a highly congested traffic. The measurements from the detector are compared with the reference measurements obtained from a traffic camera with the Mean Absolute Percentage Errors (MAPE), which has proved the usefulness of the detector in the field.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.5
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• pp.575-582
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• 2019

Advanced driving assist system can support safety of driver and passengers which may require vehicle dynamics states as well as road geometry. It is essential to have in real-time estimation of related variables and parameters. Among the road geometry parameters, road slope angle which can not be measured is essential parameter in pose estimation, adaptive cruise control and others on sag road. In this paper, Kalman filter based method for the estimation of the vehicle dynamics and road slope angle using a nonlinear vehicle model is proposed. It uses a combination of Kalman filter as Cascade Extended Kalman Filter. CEKF uses measured vehicle states such as yaw rate, longitudinal/lateral acceleration and velocity. Unknown vehicle parameters such as center of gravity and inertia are obtained by 2 D.O.F lateral model and experimentally. Simulation and Experimental tests conducted with commercialized vehicle dynamics model and real-car.

• Structural Engineering and Mechanics
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• v.82 no.2
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• pp.191-204
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• 2022

A three-mass vehicle model including one rigid mass and two unsprung masses is adopted to predict the vehicle-bridge interaction (VBI) and to establish the nonlinear coupled governing equations. To overcome the numerical instability and large computation problems concerning the vehicle-bridge system, the perturbation method is used to convert the nonlinear coupled governing equations into a set of linear uncoupled equations. Formulas for bridge's natural frequencies considering both the VBI and the dynamic responses of bridge and vehicle are proposed. Compared with the numerical results obtained by the Newmark-β method, the theoretical solutions for natural frequencies and dynamic responses are validated. The effects of the important factors of unsprung mass, vehicle damping, surface irregularity on the natural frequencies and dynamic responses of bridge and vehicle are discussed, based on the theoretical solutions.

• Journal of Auto-vehicle Safety Association
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• v.8 no.2
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• pp.30-36
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• 2016

According to revolutionary developments in automobile technologies, various electronically controlled components of vehicles are rapidly increasing. A variety of advanced vehicles (hybrid vehicle, hydrogen fuel-cell vehicle, electric vehicle, etc.) using electrical energy source are increasing, too. The electromagnetic compatibility is getting more important for development of a vehicle because those advanced vehicles are equipped with more new electronic systems. In general, electromagnetic compatibility tests consist of an electromagnetic interference (EMI) test and an electromagnetic susceptibility (EMS) test. In this paper, in order to investigate the electromagnetic interference in the cabin of vehicle by various electric and electronic components of vehicles, a series of narrowband electromagnetic emission tests are conducted. For comparison, the several digital home appliances (smartphone under charging, laptop compuer and digital camera), which are used a lot in daily lives, are tested.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.924-930
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• 2011

Maglev vehicle has two parts a vehicle body and a series of bogies. The vehicle body is connected through a pneumatic suspension on the bogie frame operating loads, vehicle weight and passengers, repeatedly during the service life. The bogie frame plays an important role in sustaining the weight of the vehicle body and controlling the magnets in the correct alignment to meet requirements of stable running on railway. It is also subjected to the levitation and guidance force and propulsion force generated by electromagnets and linear induction motor (LIM) respectively. To guarantee a vehicle system, it is necessary to identify a load test method with proper loads that the vehicle is expected to experience while in service. In this paper, a test method was proposed to verify the structural safety of vehicle body and bogie frame that are applied to an EMS(electromagnetic suspension)-type urban Maglev vehicle considering in case of not only running on the ground but also levitated running.

• Journal of Korea Multimedia Society
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• v.19 no.2
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• pp.418-427
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• 2016

A smart parking management requires to track a vehicle in a indoor parking lot and to detect the place where the vehicle is parked. An advanced parking system watches all space of the parking lot with CCTV cameras. We can use these cameras for vehicles tracking and detection. In order to cover a wide area with a camera, a fisheye lens is used. In this case the shape and size of an moving vehicle vary much with distance and angle to the camera. This makes vehicle detection and tracking difficult. In addition to the fisheye lens, the vehicle headlights also makes vehicle detection and tracking difficult. This paper describes a method of realtime vehicle detection and tracking robust to the harsh situation described above. In each image frame, we update the region of a vehicle and estimate the vehicle movement. First we approximate the shape of a car with a quadrangle and estimate the four sides of the car using multiple histograms of oriented gradient. Second we create a template by applying a distance transform to the car region and estimate the motion of the car with a template matching method.

• Journal of Auto-vehicle Safety Association
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• v.8 no.1
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• pp.13-18
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• 2016

More than 80 percent of traffic accidents related with lane departure believed to be the result of crossing the lane due to either negligence or drowsiness of the driver. Lane-departure related accident in the highway usually involve high fatality. Even though LDWS is believed to prevent accident 25% and reduce fatalities by 15% respectively, its effectiveness in performance is yet to be confirmed in many aspects. In this study, the vehicle lateral locations relative to warning zone envelop (earliest and latest warning zone) defined in ISO standard, ECE and NHTSA regulations are compared with respect to various factors including delays, vehicle speed and vehicle heading angle with respect to the lane. Since LDWS is designed to be activated at the speed over 60 km/h, vehicle speed range for the study is set to be from 60 to 100 km/h. The vehicle heading angle (yaw angle) is set to be up to 5 degree away from the lane (abrupt lane change) considering standard for lane change test using double lane-change test specification. The TLC is calculated using factors like vehicle speed, yaw angle and reaction time. In addition, the effect of vehicle type and reaction time have been considered to assess LDWS safety.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.32-38
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• 2015

In this paper, we analyzed the vehicle fire accidents due to damage of vehicle's electrical components, which is applied to a vehicle. In recent development of electrical components technology, approximately 40% of vehicle manufacturing parts have applied electronic circuit technology. Phenomenon such deterioration of insulating performance or electric breakdown on the vehicle's electrical components and printed circuit boards(PCBs) resulted from moisture, contamination and aging due to repetitive operations, lead to the vehicle fire. Therefore, the application of electrical components with adequate electric capacity for vehicle and usage of molding techniques using a non-combustible materials to shut off the oxygen should be applied in order to prevent vehicle fire due to damage of the electrical components and PCBs.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.54-63
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• 2011

An educational network system based on CAN protocol internal to a passenger ground vehicle has been developed. The developed network system has been applied to a commercial plug-in electrical vehicle and verified the educational applicability. To apply this in-vehicle network technology based on CAN, a suitable electric vehicle has been chosen and a CAN network structure has been designed, developed and manufactured. Since the commercial electric vehicle chosen as a test bed has its own proprietary electric network, we explain how the original electric network has been utilized and how the new network system has been designed. The developed network system on a real vehicle has been tested to show the applicability and the performance. Finally, the system has been applied at few classrooms to demonstrate how the in-vehicle network system works and to teach how to analyse the CAN signals. The developed system proven to be effective for educational purpose.