• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.333-343
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• 2000

An automatic guidance system for combine was designed to harvest paddy rice by following a predetermined path. The automatic guidance system consisted of DGPS to locate position of combine, a gyro sensor system to measure heading angle, ultrasonic sensors to detect obstacles, a hydraulic system, microcomputer as a controller, and I/O interface system. Hydraulic cylinders and valves were installed to control movement of the combine. The heading angle and the position of the combine, and ultrasonic measurements from edge were used as the inputs of the controller. The operating position of hydraulic cylinder was determined as output of the controller. The automatic guidance system was evaluated at the 45-m straight path by changing the posture of the combine. The average RMS errors were 14.0 cm without offset and 15.0 cm with 1-m offset. The DGPS provided accurate position information within the limited error to guide the combine in the field. The results showed that the automatic guidance system could guide the combine autonomously in the paddy field when the posture of the combine was changed.

• Journal of Biosystems Engineering
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• v.13 no.2
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• pp.38-45
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• 1988

This study was intended to develop the system automatically controlling travel direction of combine by means of sensing paddy rows. The control system was composed of three detecting levers having different length, micro-switch, microcomputer and electro-hydraulic control system. Sensor and control system developed was tested to estimate optimum design values and its actual performance as installed in combine. The computer simulation and performance test at simulated and actual field were conducted to test for possibility of practical use. The results of the study arc summarized. as follows: 1. The travel traces of combine hiving the conventional sensor with 2 levers and the new sensor detecting the slope of paddy rows were compared through computer simulation. Turning frequency of combine having new sensor was fewer than that of conventional sensor, but the rate of turning for the combine with new sensor was much greater than that of conventional sensor. 2. As sensor was established behind the tip of divider, the sensor itself well followed paddy rows but the tip of divider did not, resulting in divider being deviated from paddy rows. It was analyzed that the sensor should be attached closer to the tip of divider to have a better performance of the control system. 3. The greater the length of sensor lever for given location of sensor attachment and combine forward speed, the higher sensitivity of turning in control system. Moreover, increasing combine speed resulted in a worse performance of control system following paddy rows. Consequently, it was necessary that an optimum length of sensor attachment and for the range of combine operational speed. 4. Field test of combine installed with the sensor and electro-hydraulic system developed in this study showed that it may be operated smoothly and well behaved to paddy rows to 4th gear of combine speed which was 59cm/s. Consequently. it was concluded that the combine with the guidance control system developed in this study may be successfully used for paddy combining.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.684-689
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• 2000

In harvesting rice and barley using combine, the inclination of the body caused by the irregular surface condition of the field and the soil sinking from the unbalanced weight during the grain collection used to make harvesting operation difficult and even impossible. To overcome such a problem, automatic leveling control system for a combine has been developed and tested. The system was composed of the sensor for measuring left and right inclination of the combine chassis and the hydraulic control system. The adaptability of the control system was investigated by analyzing system response in time domain. And the limit angle of the leveling control was set up to be +/- 7$^{\circ}$. The proposed control and hydraulic power system was implemented to the prototype combine. The prototype combine was designed and built as a separable structure with chassis and track. This paper shows results of the leveling performance tested in the laboratory and the grain field.

• Journal of Biosystems Engineering
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• v.29 no.5 s.106
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• pp.425-432
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• 2004

In harvesting rice and barley using combine, the inclination of the body caused by the irregular surface condition of the field and the soil sinking from the unbalanced weight during the grain collection used to make harvesting operation difficult and even impossible. To overcome such a problem hydraulic system far automatic and manual leveling control of a combine has been developed. The system was composed of the combine body and the hydraulic level control system mounted on it. The maximum height of ground clearance was set up to be 290mm. And the limit angle of the leveling control was set up to be $\pm7^{\circ}$. The proposed controller and hydraulic system was implemented to the prototype combine. The prototype combine was designed and built as a separable structure with the body and the track of it. This paper shows results of a specification and design testing with the hydraulic level control system far body of combine.

• Journal of Biosystems Engineering
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• v.24 no.5
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• pp.399-406
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• 1999

This study was conducted to investigate the labor requirements and transportation cost of paddy for the different harvest and transportation systems for obtaining a basic reference to the improvement of present harvest-transportation systems. One hundred and eighty five farm households with sack type combine harvester and thirty farm households with bulk type combine harvester were surveyed for thirty counties from eight provinces except jeju and also eleven Rice Processing Complex were covered for this survey. This survey was carried from 8th. October 1997 to 5th. November 1997. For the labor requirements, bulk trailer system require 6.8th/ha, 10.3/ha for sack harvest-tractor trailer, and 8.8h/ha for bulk harvest-container bag. The machinery utilization cost for the different paddy harvest-transportation systems, combine sack harvest-tractor trailer system is 282 thousand won/ha, and most economical compared with other systems. Combine bulk harvest with tractor system was 416 thousands won/ha and combine bulk harvest with container bag system was 446 thousands won/ha. In order to propagate bulk harvest-transportation system, a proper bulk transportation means with considering road condition in the paddy field and paddy size should be developed, and considering cycle time it appeared that the proper capacity of bulk container was 3.5ton at the present.

• Journal of Biosystems Engineering
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• v.32 no.5
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• pp.332-338
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• 2007

Yield mapping is necessary for precision farming. An on-site rice weighing system for a head-feed combine was developed to measure the total weight of rice grain harvested while the combine was operated. A load cell system was used to monitor rice weights accumulated into the combine grain tank using a load cell. This method gave cumulative grain weight readings as a function of time. The system consisted of a load cell, two supporting brackets, and a computer-based data acquisition system. The weights measured with the system from two fields were compared with those obtained with a commercially available electronic balance. The response of the load cell to varying grain weights was linearly modeled, showing a coefficient of determination of 0.998 and a standard error of ${\pm}4.09kg$.

• Journal of Biosystems Engineering
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• v.14 no.2
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• pp.94-103
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• 1989

This study was intended to develop the automatic feeding depth control system of the head-feed combine which could feed the rice head into threshing unit at the optimal depth regardless of plant height and uneven ground surface. In the control system, one-board microcomputer was used for the controller instead of conventional electric circuits. Field test of the combine equipped with the control system was conducted to evaluate its overall performance. It was also investigated how the location and time delay of rice head sensor affect the system performance.

• Journal of Biosystems Engineering
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• v.34 no.2
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• pp.120-126
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• 2009

The purpose of this study was to develop a visibility evaluation system for cabin type combine. Human's field of view was classified into five levels (perceptive, effective, stable gaze, induced, and auxiliary) depending on rotation of human's head and eye. Divider, reaper lever, gearshift, dashboard, and conveying part were considered as major viewpoints of combine. Visibilities of combine was evaluated quantitatively using the viewpoints and the human's field of view levels. The visibility evaluation system for cabin type combine was consisted of a laser pointer, stepping motors to control the direction of view, gyro sensors to measure horizontal and vertical angle, and I/O interface to acquire the signals. Tests were conducted with different postures ('sitting straight', 'sitting with $15^{\circ}$ tilt', 'standing straight', and 'standing with $15^{\circ}$ tilt'). The LSD (least significant difference) multiple comparison tests showed that the visibilities of viewpoints were different significantly as the operator's postures were changed. The results showed that the posture at standing with $15^{\circ}$ tilt provided the best visibility for operators. The divider of the combine was invisible due to blocking with the cabin frame at many postures. The reaper lever showed good visibilities at the postures of sitting or standing with $15^{\circ}$ tilt. The gearshift, the dashboard, and the conveying part had reasonable visibilities at the posture of sitting with $15^{\circ}$ tilt. However, most viewpoints of the combine were out of the stable gaze field of view level. Modifications of the combine design will be required to enhance the visibility during harvesting operation for farmers' safety and convenience.

• Journal of Biosystems Engineering
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• v.32 no.5
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• pp.324-331
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• 2007

The purpose of this study is to analysis effects of defect factors of combine header for cutting speed of combine header, feeding depth of straw, and cylinder speed of thresher. Measurement system for defect factors was consists of sensors to monitor the combine operation and I/O interface to convert the signals. Cutting speed of combine header, feeding depth of straw, cylinder speed of thresher were measured and analyzed. The data were collected from three paddy field during rice harvesting. The tests were conducted at different grounding speeds, lug troubles, and cutter condition. The one way ANOVA and the multiple comparison tests were performed. The results showed that the measured data were useful to monitor the defect factors of combine during harvesting. The faults conditions of grounding speeds, lug troubles, and cutter conditions affected cutting speeds, feeding depths and cylinder speeds of the combine. The data seem to be useful to analysis the faults conditions of combine header.

• Journal of Biosystems Engineering
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• v.2 no.1
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• pp.56-80
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• 1977

This experimental work was conducted in order to find out the optimum time of harvest of Japonica-type (Akibare) and Indica-type(Tong-il) rice variety for three harvesting systems by investigating the harvesting losses and milling quality. The study was also concerned about the nature and amount of grain losses incurred during the each sequence of post-harvest technologies, and based on these result, a modification of existing systems giving a minimum grain loss was attempted. Binder, combine, and traditional systems were tested in this study and five grain moisture levels were disposed according to the decrease of grain moisture . The results are summarized as follows ; 1. The total losses of Akibare variety were ranged from 1.1 to 1.5 per cent for the traditional harvesting system , 2.1 to 4.8 per cent for the harvesting system by use of binder, and 2.8 to 4.3 per cent for the harvesting system by use of combine as the grain moisture content was reduced from 24 to 15 percent. Milling recovery of the harvesting system by use of binder, 74.8 ∼75.7 percent, was a little higher as it was compared to that of traditional harvesting system, 74.3 ∼75.0per cent, and that of the harvesting system by use of combine, 73.8 ∼75.0 per cent. Head rice recovery of mechanically dried paddy samples was higher than that of sun-dried paddy samples. 2. The total losses of Tong-il variety were ranged from 3.8 to 5.0 per cent for the traditional harvesting system, 5.2 to 10.0 percent for the system by use of binder, and 3.0 to 5.0 per cent for the system by use of combine as the grain moisture was reduced from 28 to 16 per cent. 3. Milling recovery of Tong-il variety harvested by the traditional harvesting system was 72.3 ∼73.6 percent and it was lower when compared to that of 72.3∼75.0 per cent harvested by binder, and 73.0∼74.6 percent harvested by combine. 4. Head rice recovery of Tong-il variety harvested by the traditional harvesting system (58.