• Title/Summary/Keyword: 기중기

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Safety Evaluation of Concrete Bridges for Passage of Crane Vehicle Exceeding Weight Limit (제한 중량을 초과하는 기중기 차량 통행에 대한 콘크리트 교량의 안전성 평가)

  • Lee, Sung-Jae;Yu, Sang Seon;Park, Younghwan;Paik, Inyeol
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.6
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    • pp.92-101
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    • 2020
  • It is necessary to develop a rational method for evaluating the safety of bridges for the passage of inseparable crane vehicles exceeding the limit weight. In this study, the same method applied to the development of the recently introduced reliability-based highway bridge design code - limit state design method is applied to the calibration of the live load factor for the crane vehicle. Structural analysis was performed on the concrete bridge and the required strengths of the previous design code, the current design code and AASHTO LRFD were compared. When comparing the unfactored live load effect, the live load of the crane was greater than that of the current and previous design code. When comparing the required strength by applying the calibrated live load factor, the previous design code demands the largest strength and the current design code and the crane live load effect yields similar value. The results of safety evaluation of the actual bridges on the candidate route for the crane passage secured the same reliability as the target reliability index required by the design code and the strength of the cross section of the actual bridge is calculated greater than the required strength for the passage of the crane, which confirms the safety for the passage of the crane.

Development of a frequency-to-voltage transducer in a motor (모터의 회전수-전압 변환장치 개발)

  • 김강철
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.3
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    • pp.563-572
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    • 2001
  • A conventional motor in a crane has a taco generator to feed back the number of turns to a main controller. The taco generator is contacted to a motor shaft through the coupling. Errors in a crane have often occurred because the coupling has worn out while the motor is turning. In this paper, we design the device of the frequency to voltage transducer in a motor. The device is composed of a rotary encoder, a speed measurement using PIC16F84 controller, a display, and a direction-decision block. The rotation of a motor is recognized by the rotary encoder and microcontroller counts the number of turns of a motor. The emergency signal is generated if the frequency goes over or below the speed limit of a motor. And the device can acknowledge the rotation direction of the motor after 6。 rotation. The simulation results and the test for a implemented device have shown that the transducer of a frequency to a voltage can replace a taco generator in a crane.

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Development of a device to measure the speed of motor used in a crane (기중기에 사용된 모터의 회전수 측정장치 개발)

  • 김강철;한석붕
    • Proceedings of the KAIS Fall Conference
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    • 2001.05a
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    • pp.374-377
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    • 2001
  • 본 논문에서는 기중기에 사용된 모터의 회전수를 측정하는 정치를 설계하였다. 이 장치는 로타리엔코더, 회전수를 계산하는 속도 측정부, LCD 표시부 및 모터의 방향판별회로로 구성된다. 모터의 회전수측정 장치는 모터의 회전수를 측정하여 RPM으로 표시하고, 모터가 6° 회전 후에 모터의 방향을 판별할 수 있다. 그리고 모터가 제한속도를 벗어나면 위험신호를 발생하는 신호와 회전방향을 나타내는 신호를 발생한다.

Study of Sand-drain machine using the excavator (포크레인을 이용한 샌드 드레인 시공 장비에 대한 연구)

  • Lee, Jeong-Hwan;Oh, Seong-Hun;So, Byung-Moon
    • Proceedings of the KAIS Fall Conference
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    • 2011.05b
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    • pp.954-957
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    • 2011
  • 본 논문은 기존의 샌드 드레인 시공장비의 베이스 머신인 기중기 대신에 포크레인을 이용하여 샌드 드레인 시공 장비를 개발 하였다. 그리고 세부적인 기술 개발 사항으로 전기적 타설의 방식에서 유압 타설을 통한 작업 효율 연비 향상과 구조해석을 통한 장비의 무게의 경량화를 이루었다. 그리고 리더의 각도 조절을 통하여 작업의 향상을 도모 할 수 있는 각도 조절 장치와 타설 작업의 자동 모니터링과 제어를 할 수 있는 자동제어 시스템을 개발 하였다.

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Development of the speed-measurement device of motor in a crane (기중기의 모터속도 측정장치 개발)

  • 김강철
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.638-641
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    • 2000
  • The conventional motor in a crane has a tan generator to feed back the number of turns. The tan generator is contacted to a motor shaft through the coupling. Don has been often generated because the coupling has worn out while the motor is turning. In this paper, we design the speed-measurement device of motor in a un. The device is composed of PIC16F84 controller, photo-sensor, and analog-to digital converter. The photo sensor measures the turn of a motor without contact so the device decreases the probability of errors. And The device can acknowledge the turn direction of the motor with a gin81e senor and two color reflectors.

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Container Crane Control: Modified Time-Optimal Traveling Followed by Nonlinear Residual Sway Control (컨테이너 기중기의 제어 : 수정된 시간최적주행과 비선형 잔류흔들림 제어)

  • Hong, Keum-Shik
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.5
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    • pp.630-639
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    • 1999
  • To achieve fast loading and unloading of containers from a container ship, quick suppression of the remaining sway motion of the container at the end of each trolley stroke is crucial. Due to the pendulum motion of the container and disturbances like sind, residual sway always exists at the end of trolley movement. In this paper, the sway-control problem of a container crane is investigated. A two-stage control is proposed. The first stage is a time optimal controlfor the purpose of fast trolley traveling. The second stage is a nonlinear control for the quick suppression of residual sway, which starts right after the first stage while lowering the container. The nonlinear control is investigated in the perspective of controlling an underatuated mechanical system, which combines partial feedback linearization to account for the known nonlinearities as much as possible, and variable structure control to account for the unmodeled dynamics and disturbances. Simulation and experimental results are provided.

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