• Journal of Drive and Control
• /
• v.18 no.2
• /
• pp.20-31
• /
• 2021

An excavator is a construction machine that can perform various tasks such as trenching, piping, excavating, slope cutting, grading, and rock demolishing. In the 2010s, unmanned construction equipment using ICT technology was continuously developed. In this paper, the path design process was studied to implement the output data of the decision stage, and the path design algorithm was developed. For example, the output data of the decision stage were terrain data around the excavator, excavator mechanism information, excavator hydraulic information, the position and posture of the bucket at key points, the speed of the desired bucket path, and the required excavation volume. The result of the path design was the movement of the hydraulic cylinder, boom arm, bucket, and bucket edge. The core functions of the path design algorithm are the function of avoiding impact during the excavation process, the function to calculate the excavation depth that satisfies the required excavation volume, and the function that allows the bucket to pass through the main points of the excavation process while maintaining the speed of the desired path. In particular, in the process of developing the last function, the node tracking method expressed in the path design table was newly developed. The path design algorithm was verified as this path design satisfied the JCMAS H02 requirement.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.04a
• /
• pp.475-480
• /
• 2002

The Field Robot means the machinery applied for outdoor tasks in construction, agriculture and undersea etc. In this study, to field-robotize a hydraulic excavator that is mostly used in construction working, we developed an interfacing hardware part of stroke sensing cylinder using magnetic sensor and estimated its performance. It is illustrated by experiment that the proposed control system by stroke sensing cylinder gives good performances in the position control

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.4
• /
• pp.148-154
• /
• 2000

In this study, the static and the dynamic characteristics of the load-sensitive hydraulic pump control systems of a hydraulic excavator were analyzed using the developed analysis tool. The results were compared with the experimental ones. To improve the static performance of the system, the system parameter effects on the controllable region and the pump pressure variation were studied. The parameters enhancing dynamic characteristics were also considered.

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

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.509-510
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.06a
• /
• pp.599-600
• /
• 2009

• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.5
• /
• pp.564-569
• /
• 2015

In highland crop fields, saprolite is piled up approximately every three years as deep much as 20 to 30 cm because farmers expect that adding new materials may improve productivity and mitigate hazards by continuous cultivation of a single crop. Piling saprolite, however, has been reported to induce poor soil drainage. Effects of deep ploughing with a spading machine and an excavator were studied in sites located in Daekwanryeong-myeon, Pyeongchang in which soil physical properties were deteriorated by piled saprolite. The soil made of parent material of Samgag series was piled up over surface soil of Haggog series naturally developed in the area. Carrot was cultivated in the field. Productivity and growth factors of carrot were compared among control and deep ploughing by a spading machine and an excavator. Effective soil depth extended to 60 cm or greater by 60 cm deep ploughing by an excavator or 50 cm deep ploughing by a spading machine. On the other hand, effective soil depth was within 50 cm at control plot. Productivity of carrot responded to amelioration of soil physical properties. The productivity was greater in deep ploughing treatments than that of control or 30 cm ploughing. It suggested that increased productivity by deep ploughing was mainly related to breaking plough pan which inhibited extension of rooting zone.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1190-1194
• /
• 2007

Since the dismantling processes of building are very dangerous, there have been many studies to develop a remote operating devices using joystick. In this paper, in order to improve the operability of the dismantling actuator that is usually an excavator, a novel concept of tele-operated haptic device is proposed. Operators who use this haptic device with additional environmental sensing devices can work safely away from the dangerous sites. First, based on the concept design of the haptic device, the workspace mapping from the haptic device to the excavator is explored. Second, the kinematics which deals with the conversion from the 3 dimensional position information of the haptic device to the joint variable information of the backhoe is included. Lastly, 3D graphical simulation of both haptic device and the backhoe will be shown. This new design of the haptic device can be easily manufactured and gives the workers very convenient and transparent remote control capability.

• Journal of Drive and Control
• /
• v.16 no.4
• /
• pp.9-15
• /
• 2019

Bucket trajectory is crucial regarding precision work with an excavator. In general, the bucket trajectory deviation is determined by the machining deviation of the frame, driving deviation of the driving hydraulic cylinder, clearance in the joints, and deformation of the structure. This paper investigated the relationship between the respective clearance in joints and the trajectory deviation of the bucket at the finishing work of the ditching for a 20-ton excavator. As a result, the larger the clearance, the larger deviation is increased at trajectory. However, it was found that the deviation of the rotation angle and displacement of the bucket was limited and the size of clearance does not affect closely on the contact angle of the pin shaft.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.33-34
• /
• 2006

The most bottleneck of development of automation excavator system is the making mathematical linear model. Because of non-linear of control circuit, cylinder, join in hydraulic circuit, and heavy loading so on. Therefore, whatever robust controller is designed, real experimentation is necessary. But, a real experimentation has many risks. The excavator is expensive and large size. Therefore a development of experimentation system is difficult and not safe. Specially, there have a difficulty, because of big noise. So, on experimentation is difficult in school. Manufacturing pneumatic excavator modeland using system identification, design a system transfer function in this paper. Also, planning m-PID Controller using CDM, and examining usefulness applied to actuality model.