Earticle

초록

영어

Forestry crane work in a forest harvester or forwarder is regarded as one of most hard work requiring a very high level of operation skill. The operator must handle two or more multi-axes joysticks simultaneously to control the multiple manipulators for maneuvering the crane-tip to its intended location. This study has been carried out to develop a crane-tip controller which can intuitively maneuver the crane-tip, resulting in improving the productivity by decreasing the technical difficulty of control as well as reducing the workload. The crane-tip controller consists of a single 2-axis joystick and a control algorithm run on microcontroller. Lab-scale forestry crane was constructed using electric cylinders. The crane-tip control algorithm has the crane-tip follow the waypoints generated on the given path considering the dead band region using LBO (Lateral Boundary Offset). A speed control gain to change the speed of relevant cylinders relatively is applied as well. By the P (Proportional) control within the control interval of 20 msec, the average error of crane-tip control on the predefined straight path turned out to be 14.5 mm in all directions. When the joystick is used the waypoints are generated in real time by the direction signal from the joystick. In this case, the average error of path control was 12.4 mm for straight up, straight forward and straight down movements successively at a certain constant speed setting. In the slant movement of crane-tip by controlling two axes of joystick simultaneously, the movement of crane-tip was controlled in the average error of 15.9 mm when the crane-tip is moved up and down while moving toward forward direction. It concluded that the crane-tip control was possible using the control algorithm developed in this study.

목차

Abstract
Introduction
Materials and Methods
Experimental forestry crane
Control system
Performance evaluation
Results and Discussion
Performance of crane-tip control algorithm
Performance of crane-tip control with a joystick
Conclusion
Acknowledgements
References

키워드

저자

• Ki-Duck Kim [ Department of Biosystems Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea ]
• Beom-Soo Shin [ Department of Biosystems Engineering, Kangwon National University, Interdiciplinary Program in Smart Agriculture, Kangwon National University Graduate School, Chuncheon 24341, Republic of Korea ] Corresponding author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  Journal of Forest and Environmental Science [산림과학연구]

• 간기

  계간

• pISSN

  2288-9744

• eISSN

  2288-9752

• 수록기간

  1981~2025

• 등재여부

  KCI 등재

• 십진분류

  KDC 526 DDC 634