• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.18 no.33
• /
• pp.29-37
• /
• 1995

An Automated Storage/Retrieval Systems(AS/RS) has been gradually emphasized because of the change of production and distribution environment. This paper develops algorithm and Shortest Distance Model that can reduce the traveling time of a stacker crane for efficient operation of AS/RS. In order to reduce the traveling time of a stacker crane, we determine the order processing and then the sequencing of storage/retrieval for each item. Order processing is determined based on the SPT(Shortest Processing Time) concept considering a criterion of retrieval coordinate. The sequencing of storage/retrieval is determined based on the Shortest Distance Model by using a modified SPP(Shortest Path Problem) of network problem. A numerical example is provided to illustrate the developed algorithm and Shortest Distance Model.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.1
• /
• pp.68-75
• /
• 2023

In an automotive plant, an automated storage and retrieval system (ASRS) synchronizes material handling flows from a part production line to an auto-assembly line. The part production line transfers parts on small-/large-sized pallets. The products on pallets are temporarily stored on the ASRS, and the ASRS retrieves the products upon request from the auto-assembly line. Each ASRS aisle is equipped with narrow-/wide-width racks for two pallet sizes. An ASRS aisle with narrow-/wide-width racks improves both storage space utilization and crane utilization while requiring delicate ASRS aisle design, i.e., the locations of the narrow-/wide-width racks in an ASRS aisle, and proper operation policies affect the ASRS performance over demand fluctuations. We focus on operation policies involving a common storage zone using wide-width racks for two pallet sizes and a storage-retrieval job-change for a crane based on assembly-line batch size. We model a discrete-event simulation model and conduct extensive experiments to evaluate operation policies. The simulation results address the best ASRS aisle design and suggest the most effective operation policies for the aisle design.

• IE interfaces
• /
• v.3 no.2
• /
• pp.39-51
• /
• 1990

One of the most important and powerful tools available for design and/or study of the operation of complex systems and processes is simulation. Since automated material handling systems like AS/RS are often quite complex, a network-based simulation model is developed to analyze an automobile part supplier's automated storage and retrieval system(AS/RS). The network simulation model is implemented in the SLAM Ⅱ on a VAX 8800 computer. Performance of the AS/RS was tested for 3 dispatching rules, 3 work load levels, 2 storage policies, 3 levels of stacker crane break-down, and 2 conveyor system layouts. Results indicate that the AS/RS performance is primarily affected by the dispatching rule and work load level.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2008.04a
• /
• pp.178-183
• /
• 2008

A robot crane truck is being developed by the Bridge Inspection Robot Development Interface(BRIDI) for an automated and/or teleoperated bridge inspection. At the end of the telescoping boom allows the operator to scan the bridge structure under the deck trough the camera. Boom vibration induced by wind and deck movement can cause serious problems in this scanning system. This paper presents a control system to mitigate such vibration of the robot boom In the proposed control system an actuator is installed at the end of the working boom. This control system is studied using a mathematical model analysis with LQ control algorithm and a scaled model test in the laboratory. The study indicates that the proposed system is efficient for the vibration control of the robot booms, thereby demonstrating its immediate applicability in the field.

• Management Science and Financial Engineering
• /
• v.6 no.2
• /
• pp.47-67
• /
• 2000

It is discussed how to assign delivery tasks to automated guided vehicles (AGVs) for multiple container cranes in automated container terminals. The primary goal of dispatching AGVs is to complete all the lading and discharging operations as early as possible, and the secondary goal is to minimize the total travel distance of AGVs. It is assumed that AGVs are not dedicated to a specific container crane but shared among multiple cranes. A mathematical formulation is developed and a heuristic algorithm is suggested to obtain a near optimal solution with a reasonable amount of computational time. The single-cycle and the dual-cycle operations in both the seaside and the landside operations are analyzed. The effects of pooling AGVs for multiple container cranes on the performance of an entire AGV system are also analyze through a numerical experiment.

• Journal of Korean Port Research
• /
• v.13 no.2
• /
• pp.255-266
• /
• 1999

The purpose of this paper is to describe the design of the decision support system for container terminal ship planning and to introduce the implemented system. The ship planning in container terminals consists of three major decision processes -the working schedule of gantry cranes the discharging sequence of inbound containers the loading position and sequence of outbound containers. For making these decision the proposed system can provide two ship planning modes the interactive planning mode with user-friendly GUI and the automated planning made. To implement the automated planning routine we acquired the planning rules from the expert planner in container terminals and developed an expert system based on the rules. Finally we evaluated the system developed and the potential for commercialization by using container terminal data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2010.04a
• /
• pp.167-168
• /
• 2010

Advanced countries are adopted the Eco-Green port using high energy efficiency Crane and Automated unloading system. This paper includes the case study for energy saving ECO-RTG and other automated unloading system such as, German CTA, Japan OHI, and so on.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.21 no.5
• /
• pp.421-427
• /
• 2008

A robot crane truck is developed by the Bridge Inspection Robot Development Interface(BRIDI) for an automated and/or teleoperated bridge inspection. This crane truck looks similar to the conventional bucket crane, but is much smaller in size and light-weight. At the end of the telescoping boom which is 12m long, a robot platform is mounted which allows the operator to scan the bridge structure under the deck trough the camera. Boom vibration induced by wind and deck movement can cause serious problems in this scanning system. This paper presents a control system to mitigate such vibration of the robot boom. In the proposed control system, an actuator is installed at the end of the working boom. This control system is studied using a mathematical model analysis with LQ control algorithm and a scaled model test in the laboratory. The study indicates that the proposed system is efficient for the vibration control of the robot booms, thereby demonstrating its immediate applicability in the field.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.6
• /
• pp.510-517
• /
• 2005

In this paper, an open architecture control system for automated container cranes is investigated. The hardware architecture for automating cranes is first discussed. A standard reference model for cranes based upon the OSACA platform is proposed, in which three modules are suggested: hardware module, operating system module, and application software module. Finally, a hybrid control system combining deliberative and reactive controls for autonomous operations of the cranes is implemented.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2009.05b
• /
• pp.1-4
• /
• 2009

Construction automation and robotics are being introduced as an efficient alternative to overcome troubles caused by lack of skilled labors. To accomplish effective automated construction system, design for automation(DFA) should be performed in parallel with the development of core technologies such as control and sensing of robots. In Korea, the development of robotic crane-based construction automation(RCA) system is progressing, and the research group has recently developed newly designed steel joint to improve the efficiency of the system. However, performance of the new system should be examined prior to its application on construction sites. Therefore, This study analyzed performance of the new steel frame focused on its constructibility by carrying out mock-up test. As a result, the steel frame satisfied the standards of allowable stress and deflection. It also enables to reduce the time for installation.