• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.78-83
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• 2007

The paper focuses on the establishment of optimized bucket path planning and trajectory control designated for force-reflecting backhoe reacting to excavation environment, such as potential obstacles and ground characteristics. The developed path planning method can be used for precise bucket control, and more importantly for obstacle avoidance which is directly related to safety issues. The platform of this research was based on conventional papers regarding the kinematic model of excavator. Jacobian matrix was constructed to find optimal joint angles and rotation angles of bucket from position and orientation data of excavator. By applying Newton-Raphson method optimal joint angles and bucket orientation were derived simultaneously in the way of minimizing positional errors of excavator. The model presented in this paper was intended to function as a cornerstone to build complete and advanced path planning of excavator by implementing soil mechanics and further study of excavator dynamics together.

• Journal of Drive and Control
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• v.17 no.1
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• pp.37-43
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• 2020

An intelligent excavator can be divided into Machine Guidance (MG), semi-automatic, and unmanned by technology. The MG technology excavator is equipped with a tilt sensor on each link of the excavator and a GPS is installed on the excavator body to inform the user of the position of the excavator bucket end. Machine control (MC) technology that assists the user's work can be divided into semi-automatic and fully automatic technology. The semi-automatic MC equipment has already been commercialized by Komatsu and Caterpillar. The MC excavator is equipped with an electro-hydraulic system, sensors and controllers to control the excavator bucket end according to the user's needs. In this study, the semi-automated excavator modified based on manual excavator, is equipped with an electro-hydraulic system, a controller system, multi-sensors and a control algorithm is developed to assist in excavation work such as leveling and grading. By applying the developed technology, it was possible to confirm productivity improvement compared to manual digging and leveling work. In the future, further research to improve the accuracy of the hydraulic precision control and collaborative work with heterogeneous construction equipment such as dump truck and automated collaboration tasks technology could be developed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.479-480
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• 2008

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.105-112
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• 2010

The demand for the development of automated construction equipments is gradually increasing to deal with the current problems of construction technology, such as a lack of experienced workers, the aging of engineers, safety issues, etc. In particular, earth work such as excavation is very machine-dependent, and there has been a great deal of research on the development of an intelligent excavator, which involves great safety concerns. Thus, the objective of this study is to develop the technology to enhance the safety of intelligent excavation systems by developing an omnidirectional object detection technology for the intelligent excavator and applying it to a user-friendly system. The existing literature was reviewed, and the function of various sensor technologies was investigated and analyzed. Then, the best laser sensor was selected for an experiment to determine its effectiveness. An omnidirectional object detection algorithm was developed for a user interface program, and this can be used as the fundamental technology for the development of a safety management system for an intelligent excavator.

• Journal of Drive and Control
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• v.21 no.1
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• pp.31-37
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• 2024

In this study, to prevent accidents in underground facilities during excavation, we developed a Lv.3 automated control system that can be configured as an electronic control system without changing the existing hydraulic system in a general excavator and utilized digital map information of underground facilities. We aimed to develop a strategy to prevent accidents caused by operator error. To implement this, a real-time excavator bucket end position recognition and control system was developed through angle measurement of the boom, arm, and bucket using an electronic joystick, RTK-GPS, and angle sensors. In addition, excavators are large, machine-based equipment, and it is difficult to control overshoot due to inertia with feedback control using position recognition information of the bucket tip. Therefore, feed-forward control is used to calculate the moving speed of the bucket tip in real-time to determine the target position. We developed a technology that can converge and verified the performance of the developed system through actual vehicle installation and field tests.

• Journal of the Korea Institute of Building Construction
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• v.8 no.4
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• pp.71-77
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• 2008

Earthwork is very equipment-intensive task and researches related to automated excavation have been conducted. There is an issue to secure the safety for an automated excavating system. Therefore, this paper focuses on how to improve safety for semi- or fully-automated backhoe excavation. The primary objective of this research is to develop the core technology for automated object detection in excavation work. In order to satisfy the research objective, a diverse sensing technologies are investigated and analysed in terms of functions, durability, and reliability. The authors developed detecting algorithm for the objects using laser sensor and verified its performance by several tests. The results of this study would be the basis for developing the automated object detection system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.579-580
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• 2009

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.93-100
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• 2013

Mixed model production system means that various products are manufactured alternately in a line, and it has become a popular system in the era of multi-product small-quantity production. However, in the mixed model production system using flow line, the unbalance among stations is not inevitable because the workloads of stations cannot be the same. Thus, flow line system has been replaced to cellular manufacturing system for reducing the loss of waiting due to the unbalance of stations. In this paper, we introduce the simulation case study of an automated welding line which produces the parts of excavator. The factory has considered replacing the mixed model flow line to the cellular manufacturing system based on FMC concept. The increase of production quantity is estimated about 26.7%, and the lead time is reduced more than 55%. Furthermore sensitivity analyses are conducted considering the changes of product-mix.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.343-346
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• 2007

Recent advances in automation and robotic technologies in the manufacturing industry suggest that the greater level of automation may be extremely beneficial for the construction industry. However, only some of the high-technology advances may be applied to the construction industry due to the fast-changing construction environment in which work locations are constantly changing and material, equipment, and workers are always moving. The earthwork operation for site development is a good candidate for applying automation technology, because it is a very repetitive and tedious task and needs lots of construction equipment. This paper presents the model of a construction environment and a moving plan for an automated earthwork system, which can produce an effective moving path of an excavator platform with an Octree model. To generate the moving path, the know-how of skilled operators and construction managers is added in the proposed model.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.373-376
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• 2007

The construction industry is an inevitable part of modem development. Now-a-days, the construction industry experiencing several issues related with the maintenance of productivity, quality and labor. Hence there is an immediate requirement for the development of technologies enabling the automated construction equipment. The new technologies should also assure the sufficient safety and efficiency. In the present investigation, an attempts have been made for the development of object sensing algorithm and safety control system for intelligent excavating system. we have analyzed some elemental technologies for sensing objects and also proposed a technology for safety control system as well. The proposed technology will highly influence the safe working performance of construction industry in the positive sense.