In the previous paper, a mathematical model for studying the steerability of tracked vehicles on inclined ground was developed, and its validity was experimentally verified. However, in the previous discussion of the pressure distribution of track shoe, the pressure acting upon these elements were assumed as the uniform along the track width.
The objective of this paper is to establish interaction relations for tracked vehicles with wide track shoes. In order to validate the pressure distribution of wide track shoes under road wheel, a rectangular loading plate was loaded vertically. The resulting code was employed to simulate the turning motion of a scale vehicle on an inclined ground, and good correlations were observed with the experimental data. Further, the numerical analysis by using specifications of a real vehicle was conducted to investigate the vehicle response on the up-slope and the down-slope and the effect of the terrain characteristics on steering performance.

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In succession to Part 1, the forced vibration experiment has been performed to clarify the vibration characteristics of the riding tractor with rotary tiller on the frequency ranging from 1.0[Hz] to, 10.0[Hz]. First, spring constant and viscous damping coefficient in the forward direction of the tractor were identified by phase method. Secondly, the simulation of frequency response was calculated, and simulated data were compared with measured data to discuss the validity for dynamic model. As a result, the factor which influences the difference between the simulated and the measured data in the frequency range beyond 6.0[Hz] was clarified, and showed the possibility of the vibration characteristics prediction in the forward and the pitching direction of the tractor.

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Artificial methods are mainly used for grain drying in developed countries, but most developing countries rely on natural drying traditionally. The purpose of this study is to improve the quality during sun drying. Using heat balance, drying characteristics of a thin layer of rough rice under solar radiation was investigated. More than 90% of energy absorbed by rough rice was released to ambient air, and only a little percentage was used for moisture vaporization. Effects of integrated and instantaneous radiation on drying rate were reported. Ratio of cracked rice increased by the average temperature of grain surface, and more than 20% of cracked rice was observed even when the grain surface radiation temperatures was kept under 34°C.

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Direct freezing of soybeans by liquid nitrogen were tried at various moisture contents. The results obtained from the measurements of transient temperature and the observation of bubble generation during freezing were as follows:
1) An differential equation of heat balance was introduced assuming that temperature is uniform in a soybean grain and depends on the freezing ratio of Heiss formula. The equation was solved numerically by Runge-Kutta-Gill method and the obtained one agreed well with the observed one.
2) The photographs of bubbles on the soybean surfaces during freezing revealed that the boiling mode was a nucleate one. Consequently, an equation on heat balance was developed. Analyzing this equation by Runge-Kutta-Gill method and fitting the predicted curves to the observed values, the characteristic value of α on the heat transfer in nucleate boiling of soybeans was determined.

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We made clear the effects of granularity and measuring temperature on the accuracy of calibration using wheat and brown rice. The SEC was not affected by granularity and measuring temperature. The BIAS of measured value was affected by the difference of granularity caused by species, variety of grain and milling machines, but we could remove the effect of granularity by using adequate calibration. It was also affected by measuring temperature, and as measuring temperature rose 10°C protein was predicted about 0.2% higher, while moisture was predicted about 0.1% lower. It is important not only to use specific and varietai calibration, but also to maintain the same measuring condition such as milling machine, measuring temperature and others in making calibration, to obtain accurate NIR determination.

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This paper describes a method for keeping qualities of green asparagus. The freezing temperature of material was -1.1--1.5°C, and this value was lower than the published value. The relation between respiratory rate and temperature can be expressed by Gore's formula. The results showed that the temperature of -0.5°C was most suitable for keeping qualities. Combining with film package, the period of market quality remained for 30 days. The overall score of sensory test was affected by appearance and texture.

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The attempt at a statistical treatment of water sorption by foods was made, based on the approximate method for deriving the sorption isotherm from the probability density function of adsorption energies. The use of weibull distribution leads to the Dubinin-Astakhov (DA) equation, and it was shown that this isotherm is applied succesfully to the non-porous foods. A modified DA equation suitable for foods was also derived by changing the meaning of the three paramenters theoretically. A new expression of equilibrium moisture content equation for rice was shown by the use of modified DA equation.

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Continuous separation test of an experimental conical-type paddy separator was conducted to study the flow pattern of the paddy-brown rice particles and its separating performance. The rotation speed of the conical vessel was set at a range of 15-25rpm, and the feed rate of test material, at 100-300g/min. It was found that geometric properties of the cascade in the particle flow could be expressed as a linear function of rotation speed. Newton's efficiency, which varied in the range of 0.85-0.91, was affected by the paddy-brown rice segregation both in the sectional and axial directions.

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To improve the tracking performance of an in-line type agricultural trailer, an active trailer wheel steering control system was developed and reported previously. This paper describes the experimental research into an active control system for offset trailer, and the results of practical experiment by an in-line type roll baler of real size. Step response and 90 degree turn tests were conducted by using the proto-type offset trailer equipped with the active steering control system. The experimental results show that the control system decreases off-tracking and improves followability of offset trailer having relatively smaller offset angle. Simulative operation experiment and actual grass harvest experiment using a real sized roll baler were carried out. As a result of the experiment, it is confirmed that the application of the active control method results in easy and effective operation. The system, therefore, is of practical use.

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In Part 1, it was detected that if forward velocity of a rice transplanter was almost constant, straight driving control was possible only by the information from angular velocity sensor. In this paper, the development of automatic control system for straight driving, controled only by the information from angular velocity sensor, was tried and its performence was discussed. By experimental results, lateral displacement increased proportionally to the square of forward displacement. But within the forward displacement of 10m, the automatic control system for straight driving had high accuracy. the errors of the lateral displacement was partly influenced by the output drift of the angular velocity sensor, but strongly influenced by the integral error caused by A/D converter.

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The purpose of this study is to develop an automatic teat-cup attachment in milking robot. By processing a two-valued image from a small CCD camera, a method of detecting the teat position of cow was investigated. After proofreading equations between the distance to the teat and the real coordinate were obtained by experiment, simulation using an udder model, a teat model and a marker was carried out, and the accuracy of detecting the teat position was examined. The results of the experiment showed that the maximum and the average errors of Z coord nate using a marker were +6.7mm and 1.5mm, and those of the XY plane coordinate were 2.1mm and 1.2mm respectively, in the space coordinates of a robot arm working range, i. e. X coordinate -40-+20mm, Y coordinate 370-670mm and Z coordinate to 260-460mm. The error of the detected coordinate using a teat model increased from 0mm (minimum value) in the center area of the image frame to 3.4mm (maximum value) in the fringe area.

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The decrease of agricultural machinery costs, which accounts for a large portion of total agricultural costs, is extremely important for Japanese agriculture. In this research, we investigated the reliability and durability of tractors and rotary tillers. The failure ratio of rotary tillers was the highest, about 30% of total failures. The failure distribution of tractors and rotary tillers was found to fit to the Weibull distribution, and the Weibull parameters were estimated.

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