• Title/Summary/Keyword: Collision Response

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Development of Tele-operation Interface and Stable Navigation Strategy for Humanoid Robot Driving (휴머노이드 로봇의 안전한 차량 주행 전략 및 원격 제어 인터페이스 개발)

  • Shin, Seho;Kim, Minsung;Ahn, Joonwoo;Kim, Sanghyun;Park, Jaeheung
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.11
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    • pp.904-911
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    • 2016
  • This paper presents a novel driving system by the humanoid robot to drive a vehicle in disaster response situations. To enhance robot's capability for substituting human activities in responding to natural and man-made disaster, the one of prerequisite skills for the rescue robot is the mounted mobility to maneuver a vehicle safely in disaster site. Therefore, our driving system for the humanoid is developed in order to steer a vehicle through unknown obstacles even under poor communication conditions such as time-delay and black-out. Especially, the proposed system includes a tele-manipulation interface and stable navigation strategies. First, we propose a new type of path estimation method to overcome limited communication. Second, we establish navigation strategies when the operator cannot recognize obstacles based on Dynamic Window Approach. The effectiveness of the proposed developments is verified through simulation and experiments, which demonstrate suitable system for driving a vehicle in disaster response.

Adaptive RFID anti-collision scheme using collision information and m-bit identification (충돌 정보와 m-bit인식을 이용한 적응형 RFID 충돌 방지 기법)

  • Lee, Je-Yul;Shin, Jongmin;Yang, Dongmin
    • Journal of Internet Computing and Services
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    • v.14 no.5
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    • pp.1-10
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    • 2013
  • RFID(Radio Frequency Identification) system is non-contact identification technology. A basic RFID system consists of a reader, and a set of tags. RFID tags can be divided into active and passive tags. Active tags with power source allows their own operation execution and passive tags are small and low-cost. So passive tags are more suitable for distribution industry than active tags. A reader processes the information receiving from tags. RFID system achieves a fast identification of multiple tags using radio frequency. RFID systems has been applied into a variety of fields such as distribution, logistics, transportation, inventory management, access control, finance and etc. To encourage the introduction of RFID systems, several problems (price, size, power consumption, security) should be resolved. In this paper, we proposed an algorithm to significantly alleviate the collision problem caused by simultaneous responses of multiple tags. In the RFID systems, in anti-collision schemes, there are three methods: probabilistic, deterministic, and hybrid. In this paper, we introduce ALOHA-based protocol as a probabilistic method, and Tree-based protocol as a deterministic one. In Aloha-based protocols, time is divided into multiple slots. Tags randomly select their own IDs and transmit it. But Aloha-based protocol cannot guarantee that all tags are identified because they are probabilistic methods. In contrast, Tree-based protocols guarantee that a reader identifies all tags within the transmission range of the reader. In Tree-based protocols, a reader sends a query, and tags respond it with their own IDs. When a reader sends a query and two or more tags respond, a collision occurs. Then the reader makes and sends a new query. Frequent collisions make the identification performance degrade. Therefore, to identify tags quickly, it is necessary to reduce collisions efficiently. Each RFID tag has an ID of 96bit EPC(Electronic Product Code). The tags in a company or manufacturer have similar tag IDs with the same prefix. Unnecessary collisions occur while identifying multiple tags using Query Tree protocol. It results in growth of query-responses and idle time, which the identification time significantly increases. To solve this problem, Collision Tree protocol and M-ary Query Tree protocol have been proposed. However, in Collision Tree protocol and Query Tree protocol, only one bit is identified during one query-response. And, when similar tag IDs exist, M-ary Query Tree Protocol generates unnecessary query-responses. In this paper, we propose Adaptive M-ary Query Tree protocol that improves the identification performance using m-bit recognition, collision information of tag IDs, and prediction technique. We compare our proposed scheme with other Tree-based protocols under the same conditions. We show that our proposed scheme outperforms others in terms of identification time and identification efficiency.

Characterics of Meter-In / Meter-Out Circuits to pneumatic System (공압회로에서 미터인 회로와 미터아웃 회로의 특성 비교)

  • 박재범;염만오
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.446-450
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    • 2002
  • Pneumatic system has been mainly used as main equipment for actuation and control of compressed air force in manufacturing industry, pneumatic circuit for the most part is used in Meter-Out circuit. Meter-Out circuit method is Flow Control Valve to fit in exhaust part of cylinder port. In the reverse, Meter-In circuit is Flow Control Valve to fit in input part of cylinder port. This study examines the dynamic characteristics comparison of Meter-In and Meter-Out Circuits in the pneumatic circuits. The results of the experimental research are obtained to the followings: i ) System Response is Meter-In Circuit more than Meter-Out one before cushion zone. ii) we conjectured that the collision of piston and head cover is ease to collide Meter-In Circuit more than Meter-Out one at the stroke end part.

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Investigation on the Health and Safety Hazards of Construction Workers

  • Kal, Won-Mo;Park, Jong-Tae;Son, Ki-Sang
    • International Journal of Safety
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    • v.4 no.2
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    • pp.43-46
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    • 2005
  • The construction workers might be at the risk of many occupational injuries and illnesses. To protect workers from various hazards, industrial health and hygiene systems were specified for the construction workers by law. It is important to know the actual health and safety(H&S) conditions by tasks and the characteristics of injuries and illnesses of construction workers. This study was designed to investigate the actual conditions of construction workers exposed to various harmful substances and work elements including evaluation of health status of each worker and general H&S system. Questionnaire was sent to 600 construction workers nationwide and totally 367 people responded to it having 61.67% of response rate. The common construction hazards were dust(29.6%), noise(19.3%), repetitive motions(12.0%), handling excessive heavy materials(11.2%) in order. The repetitive motions and handling heavy materials related to muscle disorders accounted for 23.2%. The accident and injury types were in order of overexertion, falling, overturning, dropping or flying, electric shock, collision, etc.

Effect on Drive Point Dynamic Stiffness and Lightweight Chassis Component by using Topology and Topography Optimization (위상 및 형상 최적화기법에 의한 샤시부품의 국부동강성 및 경량화 효과)

  • Park, Jeong-hun;Jeon, Seung-tae;Lee, Tae-jin;Kang, Jeong-dae;Kang, Myung-Chang
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.17 no.3
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    • pp.141-147
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    • 2018
  • Recently, interest in customers has shifted to the emotional quality of customers as the driving, handling, and collision stability of automobiles have been greatly improved. The NVH performance of a vehicle is quantified and evaluated from the DPDS. To improve the DPDS, we need to optimize the shape without considering the increases in thickness of the parts or additions to the parts. And at the same time, we need to establish design and analysis processes to satisfy the requirements of the DPDS.

The Study on the Impact Absorbing Behaviour of Steering Column (스티어링 컬럼의 충격 흡수 거동에 관한 연구)

  • Heo, Sin;Gu, Jeong-Seo;Choe, Jin-Min
    • 연구논문집
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    • s.25
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    • pp.23-29
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    • 1995
  • Steering column is a typical component that may injure the driver at a frontal collision accident. To protect the driver from an impact, it is very important to study the impact absorbing behaviour of steering column. The dynamic simulation were performed for the ball sleeve type impact absorbing steering column. The simulation results show similar trends to FMVSS 203 test results. Hence using the simulation program developed in this study, it is possible to predict dynamic response of steering system which is used in design modification. Impact absorbing performance of the ball sleeve type steering column with the column angle of $21^\circC$ and $26^\circC$ satisfies the safety criterion of FMVSS 203.

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Impact Performance of a Crash Member Filled with Aluminum Foam (알루미늄 폼이 충전된 충돌부재의 충격흡수 성능)

  • Kim, N.H.;Kim, J.H.;Lee, J.K.;Kim, D.
    • Transactions of Materials Processing
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    • v.20 no.8
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    • pp.555-561
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    • 2011
  • The energy absorbing characteristics of crash members in a car collision play an important role in controlling the amount of damage to the passenger compartment. Crash members filled with aluminum foam are expected to have reduced mass while maintaining or even improving the crashworthiness compared to the conventional hollow-beam types. Finite element simulations are carried out in the present work to assess the improvement of crashworthiness by the use of aluminum foam fillers. The numerical results agreed well with experimental measurements. Parametric studies are conducted to analyze the effect of impact velocity, weld strength, and initiator on the crash response.

The Study of Improve Safety for Signaling System using Communication (통신에 의한 신호시스템의 안전성 확보에 대한 연구)

  • 백종현;한성호;안태기;온정근
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.307-314
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    • 1999
  • The potential use of ranging sensors for reducing the occurrence of accidents in real environment is explored by many companies and laboratories. Most of the sensors under investigation utilize the FMCW(Frequency Modulated Continuous Wave) waveforms. The automotive environment presents to the FMCW radar sensor a multitude of moving and fixed targets and the sensor must detect and track only the targets which may pose a threat of collision or passengers accident. The sensor must function accurately in the presence of background echoes generated by moving and fixed targets, ground reflections, atmospheric noises, including rains, fog, and, snow and noise generated within the receiver. False detection of the desired target in this environment may issue false alarms. That may be dangerous to the passenger and the vehicle. A high false alarm rate is totally unacceptable. The false alarm mechanism consists of noise peaks, crossing the threshold and the undesired response of the system to off lane targets which are not potentially hazardous to the radar equipped vehicle. This paper presents an improve technique safety performance for driver-less operation using FMCW radar sensors.

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Virtual Endoscopic S/W System using the SSD Method (SSD기반의 가상내시경 S/W시스템)

  • Song, Cheol-Gyu;Kim, Nam-Gyun;Lee, Myeong-Ho
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.3245-3247
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    • 2000
  • We present an interactive virtual bronchoscopy method, which uses a tree structure of the objects and physically based camera control model. The proposed method archieves faster response by rendering only visible branches using the tree structure of the bronchus. A collision detection algorithm supplies a convenient and intuitive mechanism for examining the bronchus inner surface while a voiding collisions. We have improved the performances of navigation speed in virtual bronchoscopy.

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The Study of Improved Safety of Signalling System using Communication (통신에 의한 신호시스템의 안전성 확보에 관한 연구)

  • Baek, Jong-Hyen;Wang, Jong-Bae;Byun, Yeun-Sub;Park, Hyun-Jun;Han, Young-Jae;Kim, Kil-Dong
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.1368-1370
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    • 2000
  • The automotive environment presents to the FMCW radar sensor a multitude of moving and fixed targets and the sensor must detect and track only the targets which may pose a threat of collision or passengers accident. The sensor must function accurately in the presence of background echoes generated by moving and fixed targets, ground reflections, atmospheric noises, including rains, fog, and, snow and noise generated within the receiver. False detection of the desired target in this environment may issue false alarms. That may be dangerous to the passenger and the vehicle. A high false alarm rate is totally unacceptable. The false alarm mechanism consists of noise peaks, crossing the threshold and the undesired response of the system to off lane targets which are not potentially hazardous to the radar equipped vehicle. This paper presents an improve technique safety performance for driver-less operation using FMCW radar sensors.

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