• Title/Summary/Keyword: road vehicle

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Intensity Local Map Generation Using Data Accumulation and Precise Vehicle Localization Based on Intensity Map (데이터 누적을 이용한 반사도 지역 지도 생성과 반사도 지도 기반 정밀 차량 위치 추정)

  • Kim, Kyu-Won;Lee, Byung-Hyun;Im, Jun-Hyuck;Jee, Gyu-In
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.12
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    • pp.1046-1052
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    • 2016
  • For the safe driving of autonomous vehicles, accurate position estimation is required. Generally, position error must be less than 1m because of lane keeping. However, GPS positioning error is more than 1m. Therefore, we must correct this error and a map matching algorithm is generally used. Especially, road marking intensity map have been used in many studies. In previous work, 3D LIDAR with many vertical layers was used to generate a local intensity map. Because it can be obtained sufficient longitudinal information for map matching. However, it is expensive and sufficient road marking information cannot be obtained in rush hour situations. In this paper, we propose a localization algorithm using an accumulated intensity local map. An accumulated intensity local map can be generated with sufficient longitudinal information using 3D LIDAR with a few vertical layers. Using this algorithm, we can also obtain sufficient intensity information in rush hour situations. Thus, it is possible to increase the reliability of the map matching and get accurate position estimation result. In the experimental result, the lateral RMS position error is about 0.12m and the longitudinal RMS error is about 0.19m.

A Study on the Prior Forecast System of Crossroads Traffic Information based on Vehicle-IT for Decision Assistant (차량 IT 기반 의사결정 지원을 위한 교차로 신호 사전예보 시스템에 관한 연구)

  • Lee, Yang Sun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.9
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    • pp.2107-2113
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    • 2015
  • This paper proposed a Prior Forecast System of Crossroad Traffic Information that allows vulnerable road users to perceive traffic signal changes beforehand and respond in concentrated traffic areas such as crossroads. Also, it mapped out information linking procedures of the proposed system and it designed a PHY based wireless communication simulator to verify the operational feasibility of wireless communications. Conclusively, by conducting performance analysis according to crossroad channel environments using the simulator designed in this paper, it verified that a Prior Forecast System of Crossroads Traffic Information service for vehicle IT based decision-making support for vulnerable road users is a possibility.

A Study on Vehicle-based Durability Evaluation for Weight-reduced Valve Parts of the Dual Clutch Transmission

  • ChanEun Kim;TaeWook Kim
    • Tribology and Lubricants
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    • v.40 no.1
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    • pp.24-27
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    • 2024
  • A monotype valve body for a dual clutch transmission has the potential to reduce costs, weight, and manufacturing time by modularizing various parts, including those of existing solenoid packs and valve bodies, into one through the application of super-precision die casting technology. However, this approach may lead to challenges such as reduced rigidity and increased interference due to modularization and compactness, impacting both product performance due to the reduced weight as well as durability and reliability. Unlike existing products, this approach requires a high-precision thin-wall block to avoid more complicated flow line formation, interference between flow lines, and leaks, as well as a strict quality requirement standard and precise inspections including detection of internal defects. To conduct precise inspections, we built an equivalent model corresponding to a driving distance of 300,000 km. Testing involved simulating actual road loads using a real vehicle and a chassis dynamometer in the FTP-75 mode (EPA Federal Test Procedure). The aim of the study was to establish a vehicle load-based part durability model for manufacturing a mono-type valve body and to develop fundamental technology for part weight reduction through preliminary design by introducing analytical weight reduction technology based on the derived results.