• Title/Summary/Keyword: autonomous vehicles

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The Development of an Algorithm for the Optimal Signal Control for Isolated Intersections under V2X Communication Environment (V2X 통신환경에서의 독립교차로 신호 최적제어 알고리즘 개발 연구)

  • Han, Eum;Park, Sangmin;Jeong, Harim;Lee, Chulki;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.6
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    • pp.90-101
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    • 2016
  • This study was initiated to develop an algorithm for traffic condition adaptive optimal traffic signal control for isolated intersections based on the vehicle trajectory data. The algorithm determines the optimal cycle length, phase lengths, phase sequences using the data collected under V2X communication environment every second. In addition, the algorithm utilizes a traditional feature of the actuated signal control, gap-out, using traditional detector systems to consider the mixture of normal vehicles and vehicles equipped with the V2X communication function. The performance of the algorithm was compared with that of the fixed signal timing plan which was optimized with Synchro under a microscopic traffic simulation-based test bed. As a result, the overall performance, including average delay, average stop delay, the number of stops, and average speed, are improved apparently. In addition, the amount of improvement get bigger as the traffic volume in the intersection as well as the number of vehicles equipped with the V2X communication function increase.

Estimation of Hydrodynamic Derivatives and Dynamic Stability for Submarine Using Captive Model Test (구속모형시험을 이용한 잠수함의 동유체력 계수 추정 및 동안정성 평가)

  • Jeong, Jae-Hun;Ok, Ji-Hun;Lee, Chi-Seung;Lee, Jae-Myung;Lee, Seung-Keon
    • Journal of Navigation and Port Research
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    • v.39 no.3
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    • pp.173-178
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    • 2015
  • In these days, the world has been increasing the development of various underwater vehicles such as ROVs (Remotely operated underwater vehicles) and AUVs (Autonomous underwater vehicles). And the importance of submarine's maneuverability is especially being emphasized. Therefore, accurate values of the derivatives in equations of motion are required to control motion of the submarines. The aims of the present study are to experimentally derive Hydrodynamic derivatives derived by the vertical planar motion mechanism (VPMM) model test, and to estimate vertical dynamic stability was estimated by using the linear hydrodynamic derivatives, the hydrodynamic derivatives of the submarine, which have a high propriety, were provided by using the fourier analysis of measured forces and moments. Furthermore it is confirmed that the experimental derivatives shows well agreement with the theoretical estimations, and the dynamic stability of the submarine was estimated as a good state, which implies that the value is greater than zero.

Robust Obstacle Detection and Avoidance Algorithm for Infrastructure-Based Vehicle Communication Under Signal Interference (중계기를 통한 다중 차량 간 통신 상황에서 신호 간섭에 강한 장애물 감지 및 회피 알고리즘)

  • Choi, Byung Chan;Kwon, Hyuk Chan;Son, Jin Hee;Nam, Haewoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.5
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    • pp.574-580
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    • 2016
  • In this paper, we will introduce the system that can control multiple vehicles on the road through Single Board Computers and V2I (Vehicle-To-Infrastructure). Also, we will propose the group evasive maneuver decision algorithm, which plays a critical role in deciding whether the vehicles in the system have to conduct evasive maneuvers to avoid obstacles on the road. In order to test this system, we have utilized Wi-Fi and TCP/IP for establishing the communication between multiple vehicles and the relay server, and observed their driving states on the road with obstacles. During the experiments, we have discovered that our original decision algorithm possesses high failure rate when there is frequency interference in ISM (Industrial Scientific Medical) band. In order to reduce this failure rate, we have implemented the data transition detector. This paper will focus on how the use of data transition detector can affect the reliability of the system under the frequency interference of ISM band. If this technology is improved and applied in the field, we will effectively deal with such dangerous situations as multiple collision accidents through vehicle-to-vehicle communication or vehicle-to-infrastructure communication. Furthermore, this can be applied to the autonomous driving technologies. This can be used as the reference data for the development of the similar system.

A Study on the Characteristics and Policy Demand of the Unmanned Vehicle Industry in Gyeonggi-do (경기도 무인이동체 산업 특성과 정책수요)

  • Kim, Myung Jin
    • Journal of the Economic Geographical Society of Korea
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    • v.24 no.3
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    • pp.283-299
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    • 2021
  • As the intelligent revolution triggered by digital technology, unmanned vehicles such as self-driving cars, robots, and drones appeared, which brought about innovative changes in the industry. Gyeonggi Local government has established both an ordinance and a basic plan regarding unmanned vehicles. It is time to prepare a data-based policy by understanding the current state of the unmanned vehicle industry in the province. As a result of the survey, the unmanned vehicle industry in Gyeonggi Province is 25% of the nationwide, and more than 88% is concentrated in the southern part of Gyeonggi Province. The land sector such as the robot and autonomous vehicles are focused on 71.4% and the aviation sector such as drones are 26.7%. However, unmanned vehicle companies in Gyeonggi-do are mostly small-sized businesses with less than 10 years of experience and are in the stage of introduction and growth level. They have a plan to improve technology through continuous R&D by hiring human resources. Therefore, Gyeonggi-do needs to consider policy support for sustainable growth of start-up and small enterprises and for fostering professional manpower and technical skills as well as for establishing an unmanned vehicle industry network to create, share, and spread knowledge.

Integration and Decision Algorithm for Location-Based Road Hazardous Data Collected by Probe Vehicles (프로브 수집 위치기반 도로위험정보 통합 및 판단 알고리즘)

  • Chae, Chandle;Sim, HyeonJeong;Lee, Jonghoon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.17 no.6
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    • pp.173-184
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    • 2018
  • As the portable traffic information collection system using probe vehicles spreads, it is becoming possible to collect road hazard information such as portholes, falling objects, and road surface freezing using in-vehicle sensors in addition to existing traffic information. In this study, we developed a integration and decision algorithm that integrates time and space in real time when multiple probe vehicles detect events such as road hazard information based on GPS coordinates. The core function of the algorithm is to determine whether the road hazard information generated at a specific point is the same point from the result of detecting multiple GPS probes with different GPS coordinates, Generating the data, (3) continuously determining whether the generated event data is valid, and (4) ending the event when the road hazard situation ends. For this purpose, the road risk information collected by the probe vehicle was processed in real time to achieve the conditional probability, and the validity of the event was verified by continuously updating the road risk information collected by the probe vehicle. It is considered that the developed hybrid processing algorithm can be applied to probe-based traffic information collection and event information processing such as C-ITS and autonomous driving car in the future.

A Simulation-Based Investigation of an Advanced Traveler Information System with V2V in Urban Network (시뮬레이션기법을 통한 차량 간 통신을 이용한 첨단교통정보시스템의 효과 분석 (도시 도로망을 중심으로))

  • Kim, Hoe-Kyoung
    • Journal of Korean Society of Transportation
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    • v.29 no.5
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    • pp.121-138
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    • 2011
  • More affordable and available cutting-edge technologies (e.g., wireless vehicle communication) are regarded as a possible alternative to the fixed infrastructure-based traffic information system requiring the expensive infrastructure investments and mostly implemented in the uninterrupted freeway network with limited spatial system expansion. This paper develops an advanced decentralized traveler information System (ATIS) using vehicle-to-vehicle (V2V) communication system whose performance (drivers' travel time savings) are enhanced by three complementary functions (autonomous automatic incident detection algorithm, reliable sample size function, and driver behavior model) and evaluates it in the typical $6{\times}6$ urban grid network with non-recurrent traffic state (traffic incident) with the varying key parameters (traffic flow, communication radio range, and penetration ratio), employing the off-the-shelf microscopic simulation model (VISSIM) under the ideal vehicle communication environment. Simulation outputs indicate that as the three key parameters are increased more participating vehicles are involved for traffic data propagation in the less communication groups at the faster data dissemination speed. Also, participating vehicles saved their travel time by dynamically updating the up-to-date traffic states and searching for the new route. Focusing on the travel time difference of (instant) re-routing vehicles, lower traffic flow cases saved more time than higher traffic flow ones. This is because a relatively small number of vehicles in 300vph case re-route during the most system-efficient time period (the early time of the traffic incident) but more vehicles in 514vph case re-route during less system-efficient time period, even after the incident is resolved. Also, normally re-routings on the network-entering links saved more travel time than any other places inside the network except the case where the direct effect of traffic incident triggers vehicle re-routings during the effective incident time period and the location and direction of the incident link determines the spatial distribution of re-routing vehicles.

An Experimental Evaluation of AEB Equipped Passenger Vehicle for the Pedestrian Collision Situations (AEB 장착 승용차의 보행자 충돌상황에 관한 실험적 평가에 관한 연구)

  • Shim, Jaekwi;Lee, Sangsoo;Sun, Chisung;Nam, Doohee
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.6
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    • pp.202-210
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    • 2019
  • This paper evaluated the performance of passenger vehicles with an AEB(Autonomous Emergency Braking) for various pedestrian-vehicle collision situations. The experiment was conducted at a speed of 30-60km/h on a 2017 3,000cc vehicle using a range of collision scenarios. The results showed that the test vehicle stopped before crashing a pedestrian dummy under all scenarios at 30km/h. The test vehicle reduced the speed but crashed the pedestrian dummy in all scenarios at 40-60km/h. From the paired t-test, there was a speed difference from the AEB system at a significant level of 0.05. In addition, the percentage of speed reduction was quite different for each scenario tested. It was concluded that the current AEB system can prevent pedestrian collisions at speed of 30km/h, but cannot prevent collisions with pedestrians at speed of 40-60 km/h.

Technical Value Model and Evaluation for Smart In-vehicle Network (스마트 차량내(內) 네트워크 기술가치 모델 및 평가)

  • Kim, Byung-Woon
    • Journal of Korea Technology Innovation Society
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    • v.20 no.2
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    • pp.368-386
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    • 2017
  • The purpose of this study is to present the technology value model based on profit approach and IITP practical guide for Ethernet network technology, which is the core technology of autonomous vehicles and connected cars in the hyper-connected industry. In-vehicle network, Ethernet technology, Ethernet port count, port pricing, and application data for technology assessment are sources of global market research organizations. The data on the company's COGS (Cost of Goods Sold), operating capital requirement, capital expenditure, and income statement data are used by the Bank of Korea's Business Analysis Report. According to the results of the study, the product market size was estimated to be US $470.3 billion and the technology market size was $52.1 billion over the seven years of economic life cycle of technology. The market value of the technology was estimated to be $260 million reflecting the possibility of entry into the market. In the case of the corporate management analysis report, the average value of the IITP and the top 25% were $0.7 million and $40.2 million, respectively. -27.8 million, and -73.6 million dollars respectively. This implies that government support for policy support is needed when conducting corporate R&D with high cost-to-sales ratio. The results of this study can be used as a reference for the evaluation of technology demand based ICT R&D technology in the industrial internet market in the fourth industrial revolution era.

A Study on Analysis of R&D Intensity based on Patent Citation Information: Case Study on Self-driving Car of Google (특허인용정보 기반의 연구집중도 분석에 관한 연구: 구글의 자율주행자동차 기술 중심으로)

  • Lee, Junseok;Kim, Jongchan;Lee, Joonhyuck;Park, Sangsung;Jang, Dongsik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.4
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    • pp.327-333
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    • 2016
  • An autonomous vehicle is a convergence of artificial intelligence and a vehicle which can drive itself while analyzing the real-time situation on a road without a driver. A lot of research achievements have been revealed through the media and Google is considered to be the best leading company in this field. The use of patent information which contains various information such as bibliographic data and information about technologies is a good way to find out the R&D direction of a company and develop a reasonable strategy. This study is aimed at investigating the direction to which Google focuses its R&D capabilities and establishing strategies for technology development. Google's patents about autonomous vehicles were collected and the degree of research bias was analyzed using Social Network Analysis based on citations indicating the quality of a patent. Based on the results, the strategies for technology development was eventually proposed. As a result, it was revealed that Google focused its R&D capabilities on the part of hardware control to make up for its lack of hardware-oriented technologies. As of now, Google obtained remarkable achievements, so it seems reasonable that last-movers consider cooperative research with Google.

Performance Enhancement of Virtual War Field Simulator for Future Autonomous Unmanned System (미래 자율무인체계를 위한 가상 전장 환경 시뮬레이터 성능 개선)

  • Lee, Jun Pyo;Kim, Sang Hee;Park, Jin-Yang
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.10
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    • pp.109-119
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    • 2013
  • An unmanned ground vehicle(UGV) today plays a significant role in both civilian and military areas. Predominantly these systems are used to replace humans in hazardous situations. To take unmanned ground vehicles systems to the next level and increase their capabilities and the range of missions they are able to perform in the combat field, new technologies are needed in the area of command and control. For this reason, we present war field simulator based on information fusion technology to efficiently control UGV. In this paper, we present the war field simulator which is made of critical components, that is, simulation controller, virtual image viewer, and remote control device to efficiently control UGV in the future combat fields. In our information fusion technology, improved methods of target detection, recognition, and location are proposed. In addition, time reduction method of target detection is also proposed. In the consequence of the operation test, we expect that our war field simulator based on information fusion technology plays an important role in the future military operation significantly.