• Title/Summary/Keyword: road vehicle

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Test Bed for Vehicle Longitudinal Control Using Chassis Dynamometer and Virtual Reality: An Application to Adaptive Cruise Control

  • Mooncheol Won;Kim, Sung-Soo;Kang, Byeong-Bae;Jung, Hyuck-Jin
    • Journal of Mechanical Science and Technology
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    • v.15 no.9
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    • pp.1248-1256
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    • 2001
  • In this study, a test bed for vehicle longitudinal control is developed using a chassis dynamometer and real time 3-D graphics. The proposed test bed system consists of a chassis dynamometer on which test vehicle can run longitudinally, a video system that shows virtual driver view, and computers that control the test vehicle and realize the real time 3-D graphics. The purpose of the proposed system is to test vehicle longitudinal control and warning algorithms such as Adaptive Cruise Control(ACC), stop and go systems, and collision warning systems. For acceleration and deceleration situations which only need throttle movements, a vehicle longitudinal spacing control algorithm has been tested on the test bed. The spacing control algorithm has been designed based on sliding mode control and road grade estimation scheme which utilizes the vehicle engine torque map and gear shift information.

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A New Multimachine Robust Based Anti-skid Control System for High Performance Electric Vehicle

  • Hartani, Kada;Draou, Azeddine
    • Journal of Electrical Engineering and Technology
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    • v.9 no.1
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    • pp.214-230
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    • 2014
  • This paper presents a high performance sensor less control four motorized wheels for electric vehicle. Firstly, we applied a sensor less master-slave DTC based control to both the two in wheel motors by using sliding mode observer for its quick response and its high reliability in electric vehicle application. Secondly, to overcome the possible loss of adherence of one of the four wheels which is likely to destabilize the vehicle a solution is proposed in this paper. Thirdly, a Fuzzy logic anti-skid control structure well adapted to the non-linear system is used to overcome the main problem of power train system in the wheel road adhesion characteristic. Various Simulation results have been include in this paper to show that the proposed control strategy can prevent vehicle sliding and show good vehicle stability on a curved path.

Analysis of Dynamic Characteristics for Four-Wheel-Steering Automated Guided Vehicle(AGV) System (4륜 조향 무인 컨테이너 차량(AGV) 시스템의 동특성 분석)

  • 최재영;이영진;변성태;이권순;이만형
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.306-306
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    • 2000
  • This paper analyze the dynamic characteristics of Automated Guided Vehicle(AGV) which is being developed as a part of automation in port through DADS, one of the multi-dynamic analysis program, Previous evaluation of a vehicle is carried out through the continuous driving test of a real vehicle, however this method raise the loss of finance and time. If it is possible to analyze the dynamic characteristics of vehicle before construction completely we can compensate the loss of money and time during constructing. AGV contained containers is very heavy and its center of gravity can be easily changed with the disturbance from road or cornering. It makes AGV unsatisfied, therefore we evaluate the handling characteristics and stability of the full vehicle model. This paper contribute to establish the foundation of the development of a new system like a AGV which have a special structure.

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Design of Control Logics for Improving Vehicle Dynamic Stability (차량 안정성 향상을 위한 제어기 설계)

  • 허승진;박기홍;이경수;나혁민;백인호
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.5
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    • pp.165-172
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    • 2000
  • The VDC(Vehicle Dynamic Control) is a control system whose target is to improve stability of a vehicle under lateral motion. A lateral vehicle motion, especially on a slippery road, can lead to a hazardous situation, and the situation can even worsen by the driver`s inappropriate response. In this paper, two VDC systems, a fuzzy-based controller and an LQR-based controller have been developed. The controllers take as input the yaw rate and the sideslip angle of either body or rear wheel, and they yield the direct yaw moment signal by which the vehicle can gain stability during cornering. Simulations have been conducted to evaluate the performance of the control system. The results indicated that the controllers can successfully improve vehicle stability under potentially dangerous driving conditions.

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Design and Implementation of Certificate Revocation List Acquisition Method for Security of Vehicular Communications

  • Kim, Hyun-Gon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.7C
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    • pp.584-591
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    • 2012
  • Distributing a Certificate Revocation List (CRL) quickly to all vehicles in the system requires a very large number of road side units (RSUs) to be deployed. In reality, initial deployment stage of vehicle networks would be characterized by limited infrastructure as a result in very limited vehicle to infrastructure communication. However, every vehicle wants the most recent CRLs to protect itself from malicious users and malfunctioning equipments, as well as to increase the overall security of the vehicle networks. To address this challenge, we design and implement a nomadic device based CRL acquisition method using nomadic device's communication capability with cellular networks. When a vehicle could not directly communicate with nearby RSUs, the nomadic device acts as a security mediator to perform vehicle's security functions continuously through cellular networks. Therefore, even if RSUs are not deployed or sparsely deployed, vehicle's security threats could be minimized by receiving the most recent CRLs in a reasonable time.

A Study on Improvement of Aiming Ability using Disturbance Measurement in the Ground Military Vehicle (지상무기체계에서의 외란측정을 이용한 정밀 지향성 향상 연구)

  • Yoo, Jin-Ho;Park, Byung-Hun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.2
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    • pp.12-20
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    • 2007
  • The aiming ability is a key to improve the accuracy performance of the gun pointing system in the ground military vehicle. This paper describes the new detection method of chatter vibration using disturbance acceleration in the pointing structure. In order to analysis the vibration trends of the pointing system occurred while the vehicle driving, acceleration data obtained from vehicle was processed by using data processing algorithm with moving average and Hilbert transform. The specific mode constants of acceleration were obtained from various disturbances. Vehicle velocity, road condition and property of pointing structure were considered as factors which make the change of vibration trend in vehicle dynamics. Finally, back propagation neural networks have been applied to the pattern recognition of the classification of vibration signal in various driving conditions. Results of signal processing were compared with other condition result and analysed.

A Vehicle Routing Problem Which Considers Traffic Situation by Service Time Zones (서비스 시간대별 교통상황을 고려한 차량경로문제)

  • Kim, Ki-Tae;Jeon, Geon-Wook
    • IE interfaces
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    • v.22 no.4
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    • pp.359-367
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    • 2009
  • The vehicle travel time between the demand points in downtown area is greatly influenced by complex road condition and traffic situation that change real time to various external environments. Most of research in the vehicle routing problems compose vehicle routes only considering travel distance and average vehicle speed between the demand points, however did not consider dynamic external environments such as traffic situation by service time zones. A realistic vehicle routing problem which considers traffic situation of smooth, delaying, and stagnating by three service time zones such as going to work, afternoon, and going home was suggested in this study. A mathematical programming model was suggested and it gives an optimal solution when using ILOG CPLEX. A hybrid genetic algorithm was also suggested to chooses a vehicle route considering traffic situation to minimize the total travel time. By comparing the result considering the traffic situation, the suggested algorithm gives better solution than existing algorithms.

On-Road Car Detection System Using VD-GMM 2.0 (차량검출 GMM 2.0을 적용한 도로 위의 차량 검출 시스템 구축)

  • Lee, Okmin;Won, Insu;Lee, Sangmin;Kwon, Jangwoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.11
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    • pp.2291-2297
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    • 2015
  • This paper presents a vehicle detection system using the video as a input image what has moving of vehicles.. Input image has constraints. it has to get fixed view and downward view obliquely from top of the road. Road detection is required to use only the road area in the input image. In introduction, we suggest the experiment result and the critical point of motion history image extraction method, SIFT(Scale_Invariant Feature Transform) algorithm and histogram analysis to detect vehicles. To solve these problem, we propose using applied Gaussian Mixture Model(GMM) that is the Vehicle Detection GMM(VDGMM). In addition, we optimize VDGMM to detect vehicles more and named VDGMM 2.0. In result of experiment, each precision, recall and F1 rate is 9%, 53%, 15% for GMM without road detection and 85%, 77%, 80% for VDGMM2.0 with road detection.

An Investigation on Actual Condition and the Influence of Safety on Elementary School Road by Types of Urban Spatial Structure (도시공간구조 유형별 초등학교 통학로 실태 및 안전도 영향규명 연구)

  • Kim, Tae-Ho;Kim, Seung-Hyun;Lee, Soo-Il
    • Journal of the Korean Society of Safety
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    • v.28 no.5
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    • pp.71-77
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    • 2013
  • This Study aims at investigating actual condition on attending school road of children and analyzing empirically the characteristics of cognition and the influence of safety on school road. This study findings are as follows : 1) Walking alone to go to school is the highest rates among Commuting Mode, and Commuting distance to school is nearly doubles than range of school zone(300 m). 2) Among characteristics of urban spatial structure affecting on influence classify safety of school road, 'Commuting Distance' has been drawn to most influential variable. Especially, there are 4 types classified by commuting distance and it became obvious that the longer the distance, the lower the safety score(under 127 m=76.9 points, Over 451 m=58.3 points). 3) As a result of investigating the influence of Safety on attending school road, Vehicle commuting speed urder 127 m as internal of school zone, and Walking and crossing convenience over 451 m as external of school zone have a lot of influence on safety cognition on school road. Therefore Safety on school road should be considering the commuting distance to school among surrounding characteristics, needed for improvement plan and program based on real safety cognition of children.

The recognition prioritization of road environment for supporting autonomous vehicle (자율주행차량의 도로환경 인식기술 지원을 위한 우선순위 선정 방안)

  • Park, Jaehong;Yun, Duk Geun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.595-601
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    • 2018
  • The era of autonomous vehicles, which drive themselves and in whose operation the driver does not intervene, is fast approaching. The safety of autonomous vehicles can be guaranteed only if they recognize the road infrastructure. However, the road infrastructure consists of road safety facilities, traffic operation systems, and cross-sectional concerns, which include a variety of components, such as types, shapes, and sizes. Therefore, it is necessary to prioritize the road information. This study was conducted to select the priority with which the road infrastructure attributes should be acquired using the AHP (Analytical Hierarchy Process) method. The road infrastructure attributes were categorized into 2 levels, levels 1 and 2, which consisted of 3 and 26 types of attributes, respectively. As a result of the AHP analysis, it was found that the highest priorities of the road infrastructure are the road safety facilities, traffic operation systems and cross sectional concerns. Also, in level-2, the priorities of the safety barriers (road safety facilities), traffic signals (traffic operation systems), and the median (cross sectional) are the highest. Also, this study provides application examples of road infrastructure extraction with the Point Cloud. The results are expected to support the recognition of technology for autonomous vehicles.