• International Journal of Automotive Technology
• /
• 제7권7호
• /
• pp.777-784
• /
• 2006

The lateral dynamic behaviours of a track inspection vehicle with laterally guided system are studied for the safety and comfort. A 10-DOF dynamic model is proposed counting for lateral and yaw motions. The equations for motions of the vehicle running on curved tracks at a constant speed are presented. It is shown by simulation that lateral guiding forces applied to the guiding wheels on the inner side of the track increase in a larger scale in comparison with those on the outer side when the vehicle passes through curved tracks with cant, and the front guiding spring forces is larger than the rears. Lateral vibrations due to yaw motions of the vehicle take place when the vehicle runs through curved tracks. Finally, effect of the lateral guidance on the vehicle dynamics is also examined and advantages of such a guiding system are discussed in some details. An optimal guided control is applied to restrain the lateral and yaw motions. The comparisons between the active and passive guidance explain the effect of the active control approaches.

• 한국자동차공학회논문집
• /
• 제20권4호
• /
• pp.16-24
• /
• 2012

This paper proposes a method utilizing Differential Global Position System (DGPS) with Real-Time Kinematic (RTK) and pre-built Geo-graphic Information System (GIS) to detect lane departure of a vehicle. The position of a vehicle measured by DGPS with RTK has 18 cm-level accuracy. The preconditioned GIS data giving accurate position information of the traffic lanes is used to set up coordinate system and to enable fast calculation of the relative position of the vehicle within the traffic lanes. This relative position can be used for safe driving by preventing the vehicle from departing lane carelessly. The proposed system can be a key component in functions such as vehicle guidance, driver alert and assistance, and the smart highway that eventually enables autonomous driving supporting system. Experimental results show the ability of the system to meet the accuracy and robustness to detect lane departure of a vehicle at high speed.

• 한국자동차공학회논문집
• /
• 제12권4호
• /
• pp.163-172
• /
• 2004

Nowadays, to analyze the dynamic characteristics of the automotive driving system, the computer simulation linked up with VR(Virtual Reality) technology is treated as the useful method with the improvement of computing ability. In this paper, the VR simulation system has been developed to investigate the driving characteristics of the ASV(Advanced Safety Vehicle) equipped with an ACC(Adaptive Cruise Control) system. For the purpose, VR environment which generates 3D graphic and sound information of the vehicle, the road, the facilities, and the terrain has been organized for the driving reality. Mathematical models of vehicle dynamic analysis including the ACC model have been constructed for computer simulation. The ACC modulates the throttle and brake functions to regulate the vehicle speed so that vehicles could keep proper spacing. Also, the real-time simulation algorithm synchronizes vehicle dynamic simulation with the graphic rendering. With the developed VR simulation system, simple scenarios are applied to analyze the dynamic characteristics. It is shown that the VR simulation system could be useful to evaluate the adaptive cruise controlled vehicle on various driving conditions.

• Journal of Mechanical Science and Technology
• /
• 제16권10호
• /
• pp.1287-1295
• /
• 2002

In this work, the fuel economy of a parallel hybrid electric vehicle is investigated. A vehicle control algorithm which yields operating points where operational cost of HEV is minimal is suggested. The operational cost of HEV is decided considering both the cost of fossil fuel consumed by an engine and the cost of electricity consumed by an electric motor. A procedure for obtaining the operating points of minimal fuel consumption is introduced. Simulations are carried out for 3 variations of HEV and the results are compared to the fuel economy of a conventional vehicle in order to investigate the effect of hybridization. Simulation results show that HEV with the vehicle control algorithm suggested in this work has a fuel economy 45% better than the conventional vehicle if braking energy is recuperated fully by regeneration and idling of the engine is eliminated. The vehicle modification is also investigated to obtain the target fuel economy set in PNGV program.

• 한국생산제조학회지
• /
• 제24권1호
• /
• pp.124-129
• /
• 2015

The performance of a passenger vehicle has been greatly improved recently owing to the intensive use of electronic controllers. Many components of a vehicle, including the engine, are controlled by electronic systems installed in the vehicle. Therefore, the electrical power required for such electronics has increased significantly. However, the electrical power generated by the vehicle's alternator, operated by the engine, is limited, and when the vehicle is started, a large instantaneous current is required. The voltage of the vehicle electrical system fluctuates to a very low level, then, it is gradually recovered. This case is very severe and can even cause damage to electronic systems. In this study, a voltage-stabilizing module comprising electric double layer supercapacitors, which could alleviate the voltage variation, was developed and tested.

• 한국자동차공학회논문집
• /
• 제13권1호
• /
• pp.76-82
• /
• 2005

In this paper, validation of Driver Steering Model has been conducted. The comparison between the simulation model and vehicle test results shows that the model is very feasible for describing combined human driver and actual vehicle dynamic behaviors. The 3D vehicle model is consisted of 6-DOF sprung mass and 4-quarter car model for vehicle body dynamics. Powertrain model including differential gear and Pacejka tire model are applied. The driver steering model is also validated with vehicle test result. The driver steering model is based on angle and displacement error from the desired path, recognized by driver.

• International Journal of Railway
• /
• 제5권4호
• /
• pp.156-162
• /
• 2012

When a vehicle passes through turnout, it is required to minimize the changes of lateral force for running safety of vehicle. Therefore, it is necessary to analyze interaction between the vehicle and the turnout in order to estimate the lateral force and the derailment coefficient on the turnout. In this paper, analysis model of the vehicle and turnout are established and analysis is carried out when the vehicle passes through turnout in order to improve running safety of the vehicle on turnout. To verify the vehicle and turnout analysis model, the contact points between wheel and rail and the influence of changing cradle and tongue rail are also discussed.

• International Journal of Automotive Technology
• /
• 제7권3호
• /
• pp.377-383
• /
• 2006

This paper presents evaluation and comparisons of manual driving and driving with intelligent cruise control(ICC) systems. An intelligent vehicle cruise control strategy has been designed to achieve natural vehicle behavior of the controlled vehicle that would make human driver feel comfortable and therefore would increase driver acceptance. The evaluation and comparisons of the ICC and manual driving have been conducted using real-world vehicle driving data and an ICC vehicle simulator.

• 한국통신학회논문지
• /
• 제40권3호
• /
• pp.602-612
• /
• 2015

현재 표준 차량 통신 프로토콜인 IEEE 802.11p는 차량 간 한 홉 전송을 수행하기 때문에 차량 환경에서 효율적인 정보 전달을 수행하는데 한계가 있다. 본 논문은 차량 환경에서 효율적인 정보 전달을 위해 무선 근거리 통신 중 하나인 LTE-D2D 기술을 사용한 차량 네트워크를 제안한다. 이때 전송 메시지 형태는 IP 패킷 옵션을 지닌 이름 기반 정보 메시지를 사용하고 일반 차량 노드는 요청하는 메시지를 중간 매개 노드인 대형 차량 노드로 전송하여 정보를 전송 받는다. 성능 분석을 통해 셀룰러 네트워크와 제안된 LTE-D2D 차량 네트워크에서의 패킷전달 시간에 따른 데이터 처리율을 비교하였다.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2006년도 하계종합학술대회
• /
• pp.351-352
• /
• 2006

The objective criterion is necessary to decide the signal for vehicle audio. In this time, the signals have decided by golden ear or some simple parameters. In this paper, we propose the system for sound quality assessment in the vehicle audio signals. The vehicle audio signals were recorded in many vehicles by same condition. From these signals, objective and subjective parameters were extracted and using these signals listening test was done. The function was estimated between three results by simple neural network system. The score of arbitrary signal can be estimated using the function made by three results. In this way, Sound signal quality is assessed objectively.