• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 추계학술대회 논문집
• /
• pp.463-466
• /
• 2002

The Field Robot means the machinery applied for outdoor tasks in construction, agriculture and undersea etc. In this paper, to field-robotize a hydraulic excavator, we have proposed a robust and systematic controller design method. Disturbance observer is used as inner controller to reshape the excavating system into the linear dynamics of nominal model by compensating coupled nonlinear terms, model uncertainties and external load variations. Using the linear model that is obtained through off-line system identification, a H control scheme is applied to construct a disturbance observer and a servo-controller systematically.

• Journal of Biosystems Engineering
• /
• 제32권5호
• /
• pp.339-347
• /
• 2007

A hexapod walking robot had been developed for gathering information in the field. The developed robot was $260{\times}260{\times}130$ ($W{\times}L{\times}H$, mm) in size and 14.7 N in weight. The legs had nineteen degrees of freedom. A leg has three rotational joints actuated by small servomotors. Two servomotors placed at ankle and knee played the roles of vertical joint for up and down motions of the leg and the other one placed at coxa played the role of horizontal joint for forward and backward motions. In addition, a servomotor placed at thorax between the front legs and the middle legs played the role of vertical joint for pumping the two front legs to climb stair or inclination. Walking motion of the robot was executed by tripod gait. The robot was controlled by manual remote-controller communicated by an infrared ray. Two controllers were equipped to control the walking of the robot. The sub-controller using PIC microcomputer (Microchips, PIC16F84A) received the 16 bit command signal from the manual remote controller, decoded it to 8bit and transmitted it to the main microcomputer (RENESAS, SH2/7045), which controlled the 19 servomotors using the PWM command signals. Walking speeds were controlled by adjusting the period of command cycle and the stride. Forward walking speed were within 100 cm/min to 300 cm/min. However, experimental walking speed had the error of 4-40 cm/min to compare with the theoretical one, because of slippage of the leg and the circular arc motion of servomotor of coxa.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2009년도 추계학술대회 논문집
• /
• pp.167-168
• /
• 2009

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 2005년도 동계 학술대회 논문집
• /
• pp.377-384
• /
• 2005

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 2005년도 동계 학술대회 논문집
• /
• pp.369-376
• /
• 2005

• 로봇학회논문지
• /
• 제11권1호
• /
• pp.1-8
• /
• 2016

In this paper, we propose a new algorithm of the guidance line extraction for autonomous agricultural robot based on vision camera in paddy field. It is the important process for guidance line extraction which finds the central point or area of rice row. We are trying to use the central region data of crop that the direction of rice leaves have convergence to central area of rice row in order to improve accuracy of the guidance line. The guidance line is extracted from the intersection points of extended virtual lines using the modified robust regression. The extended virtual lines are represented as the extended line from each segmented straight line created on the edges of the rice plants in the image using the Hough transform. We also have verified an accuracy of the proposed algorithm by experiments in the real wet paddy.

• 한국전자통신학회논문지
• /
• 제16권4호
• /
• pp.749-754
• /
• 2021

농업인구의 감소, 고령화 등의 문제를 해결하기 위해 다양한 농작업의 자동화를 목적으로 농업용 로봇의 연구가 활발히 진행 중이다. 농가 작업 중 가장 노동력이 많이 투입되는 과정은 수확 과정으로 타 과정 대비 약 2~3배 소모된다. 농가의 수확물 이송 작업은 인건비가 가장 많이 들고 작업 중 부상의 위험성도 있기 때문에 이송 작업을 농업용 로봇을 통해 자동화시키면 안전성 향상과 더불어 생산성을 대폭 향상할 수 있다. 따라서 본 논문은 농가 작업 현장에 최적화되고 자율주행이 가능한 농업용 로봇을 제안한다.

• 드라이브 ㆍ 컨트롤
• /
• 제19권2호
• /
• pp.1-10
• /
• 2022

Field robots operate in various areas, including construction, agriculture, forestry and manufacturing. Typical tasks of field robots used in various areas include excavation, flattening, and demolition. Such tasks are often accomplished in narrow alleys or indoors. In the case of field robots, there is a limit to working in a small space. Thus, to compensate for these shortcomings, many field robots equipped with Tiltrotators have recently been observed. The advantages of Tiltrotator are improved task efficiency and reduced operating time by reducing unnecessary behavior. We need simulation models that can improve the ability of new people to work and simulate tasks in advance. Thus, in this paper, we developed a simscape-based simulation model and modeling of 6DOF systems for field robots equipped with Tiltrotator. Dynamic modeling of field robot 3D models using Simcape multibody and hydraulic systems of field robots using Simcape Hydraulics were modeled. We applied a PID controller to create a control system that operates along the input angle. Simulation results show that errors occur when comparing input and output angles, but overall, they move along input angles.

• 농업과학연구
• /
• 제49권4호
• /
• pp.837-845
• /
• 2022

In this study, tomato maturity was estimated based on deep learning for a harvesting robot. Tomato images were obtained using a RGB camera installed on a monitoring robot, which was developed previously, and the samples were cropped to 128 × 128 size images to generate a dataset for training the classification model. The classification model was constructed based on convolutional neural networks, and the mean-variance loss was used to learn implicitly the distribution of the data features by class. In the test stage, the tomato maturity was estimated as a continuous index, which has a range of 0 to 1, by calculating the expected class value. The results show that the F1-score of the classification was approximately 0.94, and the performance was similar to that of a deep learning-based classification task in the agriculture field. In addition, it was possible to estimate the distribution in each maturity stage. From the results, it was found that our approach can not only classify the discrete maturation stages of the tomatoes but also can estimate the continuous maturity.

• 반도체디스플레이기술학회지
• /
• 제17권3호
• /
• pp.65-69
• /
• 2018

In this paper, we have developed a multi-attitude monitoring system for running farm robots for field farming. There are many agricultural robots that can select work modules for various tasks. In order to control the stable attitude of agricultural robots connected to each other, we developed a system for monitoring the roll angle and pitch angle difference by fusing the information of the attitude monitoring system mounted on the robot mainframe and the work module. The developed attitude monitoring system showed resolution below 1 degree. In this paper, roll angle difference of 20 degrees and 60 degrees is measured with a multi - attitude monitoring system.