An X.,Beijing Research Center for Intelligent Agricultural Equipment |
Meng Z.,Beijing Research Center for Intelligent Agricultural Equipment |
Wu G.,Beijing Research Center for Intelligent Agricultural Equipment |
Guo J.,Beijing Research Center for Intelligent Agricultural Equipment
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014
Both the ever-increasing prices of fertilizer and growing ecological concern over chemical run-off into sources of drinking water have brought the issues of precision agriculture and site-specific management to the forefront of present technological development within agriculture and ecology. Soil is an important and basic element in agriculture production. Acquisition of soil information plays an important role in precision agriculture. The soil parameters include soil total nitrogen, phosporus, potassium, soil organic matter, soil moisture, electrical conductivity and pH value and so on. Field rapid acquisition to all the kinds of soil physical and chemical parameters is one of the most important research directions. And soil parameter real-time monitoring is also the trend of future development in precision agriculture. While developments in precision agriculture and site-specific management procedures have made significant in-roads on these issues and many researchers have developed effective means to determine soil properties, routinely obtaining robust on-the-go measurements of soil properties which are reliable enough to drive effective fertilizer application remains a challenge. NIRS technology provides a new method to obtain soil parameter with low cost and rapid advantage. In this paper, research progresses of soil on-the-go spectral sensors at domestic and abroad was combed and analyzed. There is a need for the sensing system to perform at least six key indexes for any on-the-go soil spectral sensor to be successful. The six indexes are detection limit, specificity, robustness, accuracy, cost and easy-to-use. Both the research status and problems were discussed. Finally, combining the national conditions of china, development tendency of on-the-go soil spectral sensors was proposed. In the future, on-the-go soil spectral sensors with reliable enough, sensitive enough and continuous detection would become popular in precision agriculture. © 2014 SPIE.
Zhang X.,Beijing Research Center for Intelligent Agricultural Equipment |
Zhang X.,China Agricultural University |
Guo R.,Beijing Research Center for Intelligent Agricultural Equipment |
Li W.,Beijing Research Center for Intelligent Agricultural Equipment |
And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015
Soil temperature is one of most important physical parameters of the soil. It effects the physical, chemical and biochemistry characteristics of the soil. Soil temperature also associates with the crop's growth and physiological process. The soil temperature measurement technology and sensors which are widely used come from the industry. But in the application of soil humidity and meteorological environment geography fields, Soil temperature sensor has the disadvantages of unsuitable structure, selection in sensitive element blindness and unscientific measure method. Based on the analysis of soil temperature measurement requirements in agriculture, sensor structure and sensitive element choice, the paper promoted the assembled structure which had optimization in the design of soil temperature sensor. The temperature sensing region length was reduced to 2 cm. The new design of soil temperature sensor was composed of sensing region and glass fiber reinforced plastics catheter. Lower coefficient of temperature conductivity material was used as catheter could decrease the influence of traditional long sleeve type sensor. The new design can be assembled to measure the single point, multi point and multi-layers' soil temperature. Experiments had been designed to compare the new designed sensor with the traditional sensors in sensing structures (stainless steel sleeve type & sensing region and supporting rod separation type), packaging materials (epoxy resin & silicone rubber), measurement accuracy and insert approach (horizontal & vertical). Soil temperature sensor's selection for application could be brought out according to the experiments. The soil temperature measured by traditional insert sensor has big differences in vertical and horizontal methods. The experiment indicated that the accuracy requirements of single point measurement and multi-layer measurement are different. The result showed that the assembled sensor had the accuracy below ±0.2℃, and the response time is less than 100 seconds in the span of 20 centigrade. Influence of temperature in probe insert methods was about 0.2℃, and the horizontal approach was lower than vertical approach. The new sensor decreased the influence in structure, package and measurement approach. It improved applicability and flexibility of soil temperature sensor, and also raised the scientificity and accuracy in soil temperature measurement technology. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Wang J.,Northeast Agricultural University |
Zhang C.,Beijing Research Center for Intelligent Agricultural Equipment |
Zhou W.,Northeast Agricultural University |
Pan Z.,Northeast Agricultural University |
And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2016
In recent years, as China government policies in agriculture are focused on improving agriculture machinery, deep-fertilization liquid fertilizer applicator with high efficiency, low price, easy operation and environment protection attracts more and more concerns. Deep fertilization for liquid fertilizer is a technology that liquid fertilizer is application accurately in 120-150 mm depth soil, which decreases fertilizer volatilization, increases crop's nutrient absorbance in fertilizer, decreases environmental pollution brought by fertilizer, and increases crop yield and quality. Deep fertilization for liquid fertilizer is to make the liquid fertilizer into the soil. Northeast Agricultural University developed all elliptic planetary gears for pricking hole mechanism of 1YJ-140 type deep-fertilization liquid fertilizer applicator. Although the mechanism was obtained via using design method for obverse operation, there were a certain blindness in the process of seeking the optimal parameters and a long process of seeking parameters. The transmission part of pricking hole mechanism adopted all elliptic planetary gears so its transmission ratio was fixed. It was difficult to find a perfect path curve. So the non-circular planetary gear trains for pricking hole mechanism was proposed. Several date points on the motion trace of fertilizer-spraying needle tip were selected, and then the curve fitting technique of cubic non-uniform B-spline was applied to control and ascertain the whole trace curve. The inverse kinematics model of the pricking hole mechanism was established on this basis. Then, other parameters could be reversed easily. To meet agronomic requirements of verticality and hole mouth size for deep-fertilization liquid fertilizer machine' fertilizer-spraying needle when it came in and went out of the soil, the simulation software of reverse design and kinematics analysis was compiled, which was for pricking hole mechanism of the non-circular gear planetary system. The software avoided the blindness that the obverse design method tried the wrong parameters. By changing the coordinates for some types of value points on static trajectory to control fertilizer-spraying needle point posture, the reverse process, simulation result and mechanism motion process were showed intuitively and dynamically, and the optimized parameters were that the gears' center distance was 61.5 mm, the distance between planetary gear center and fertilizer-spraying needle point was 161 mm, the cave mouth width was 28 mm, the track height was 252 mm and the width was 182 mm. High-speed photography bench was established and tested. The relative motion trajectory of fertilizer-spraying needle point and the key point posture were inspected in the process of actual operation. The results showed that the fertilizer-spraying needle point trajectory height was 246 mm and the width was 188 mm, and the accuracy and feasibility of reverse design and analysis were validated. This study uses many methods such as theoretical analysis mathematics, computer numerical simulation, high speed camera technology and rack experiments, and provides the reference for improving agricultural machinery quality and fertilizer applicator design level. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.