This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a signifi...This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs （about 20%）. This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field.展开更多
This paper presented a novel variable rate fertilization system based on the method of adjusting the active feed-roll length of a fluted roller.The feasibility of this method was discussed using analysis of the fluted...This paper presented a novel variable rate fertilization system based on the method of adjusting the active feed-roll length of a fluted roller.The feasibility of this method was discussed using analysis of the fluted roller model.One seed drill produced by Kuhn Company(France),which could sow and fertilize simultaneously,was used as a test platform to implement the mechanical structure of variable rate fertilization.The design methods for the variable rate fertilization mechanical structure and actuator were introduced in detail.A low-cost and stable embedded support decision subsystem and corresponding software were developed.The support decision subsystem is based on grid management.Each grid field cell contains information about corresponding spatial position and fertilizer application rate.A SpatiaLite database was employed to solve the spatial location search and spatial data query.Experiments were conducted to evaluate the fertilization uniformity and dynamic response time.The average value of coefficient of variation is 8.4%in five different active feed-roll lengths which reflects good uniformity.The dynamic response times for the adjustment of variable rate fertilization system from 204 kg/hm^(2) to 319 kg/hm^(2) and 319 kg/hm^(2) to 204 kg/hm^(2) are about 4.2 s.The results suggest that the variable rate fertilization system performs well in dynamic adjustment and stability.展开更多
The key technical problem of variable rate fertilization system based on spectrum information was precise variable fertilization in certain area according to the acquired spectrum information.Hysteretic fertilizing is...The key technical problem of variable rate fertilization system based on spectrum information was precise variable fertilization in certain area according to the acquired spectrum information.Hysteretic fertilizing is a critical problem in most of current fertilizer equipment.Hysteresis model was built and analyzed in this study to improve the system.Fertilizing tests were conducted on different wheat breeds and the results were analyzed.The tests showed that variable rate fertilization had obvious hysteresis phenomenon with the maximum lag distance of 3.82 m,the minimum lag distance of 1.73 m and average of 3.06 m.Hysteresis phenomenon of the variable rate fertilization system was obviously decreased when implanting a correction time of 2.04 s with the maximum lag distance of 0.61 m.Variable effects varied by different wheat breeds.Variable rate fertilization had an advantage of improving spatial differences of Yangmai-23,and the spatial variability of which decreased by 14.23%.In the small test area,the amount of fertilizer in Zhenmai-168 decreased by 2.84 kg,while the amount of which in Yangmai-23 increased by 3.83 kg.Yield of Zhenmai-168 in small area was lower than that in traditional pattern,but the condition of Yangmai-23 was on the contrary.Valuable information for increasing performance of fertilization in variable rate fertilization system was provided in this paper.展开更多
In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between s...In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between suspension parameters and penetrating distance was analyzed,and a matching model between fertilizing quantity and penetrating distance was established.The variable rate fertilization control machine was developed based on an Advantech PCM-9363 industrial control mainboard.The machine operates under two patterns:DGPS-based positioning and straight-line path positioning based on a planar coordinate system.This machine can perform on-demand fertilization according to the spatial differences in soil nutrients and the prescription maps pre-set before the operation.Field experiments showed the machine has a subsoiling stability of 92.5%,a soil breaking rate of 61.1%,a maximum positioning relative error of 2.68%and a maximum variable rate fertilization error of 3.89%.The subsoiling performance and variable rate fertilization indices of this machine satisfy the requirements of GB/T24675.2-2009.The tested indices meet the national and industrial standards and satisfy the design requirements.The findings of the research can be used as the structural design of the subsoiling variable rate fertilization machine.展开更多
Potato is one of the key crops for ensuring food security and can be a potential substitute for cereal crops due to its high yielding nature and nutritional value.Crop nutrient management practices within potato field...Potato is one of the key crops for ensuring food security and can be a potential substitute for cereal crops due to its high yielding nature and nutritional value.Crop nutrient management practices within potato fields are implemented uniformly without considering crop requirements and soil variability,causing uneven and low yield.However,yield can be increased by identifying growth and yield-limiting factors.Geospatial tools are robust and effective in identifying the spatial variations within the field.Proximal sensing allows quick analysis of soil and plant characteristics,decreases the need for laborious and expensive soil and plant sampling,and strengthens precision agriculture techniques.The aim of the study was to quantify the soil spatial variability and identify potato crop growth and yield limiting factors for the optimization of inputs.Two fields were selected in the subtropical region of Pakistan(Koont,Rawalpindi),and each field was cultivated with two different potato varieties.A grid sampling approach was developed to collect soil samples and tuber yields.The soil was tested for nitrogen(N),phosphorus(P),potassium(K),pH,electrical conductivity(E.C),temperature,and moisture content(M.C)by using a soil proximal sensor.Normalized difference vegetation index(NDVI)was recorded using a handheld GreenSeeker,and chlorophyll was estimated using a chlorophyll meter.Descriptive statistics and correlation analysis for soil and crop parameters were performed in Minitab 21,while geostatistical analysis was performed in Arc Map 10.8 to show spatial variability and to generate kriged maps of different soil properties.The coefficient of variation of soil properties and plant parameters showed moderate to high variability within the field,except for pH and temperature.The correlation matrix suggested that N,P,K,E.C.,chlorophyll,NDVI,plant height,and leaf area had a significant relationship with potato yield.Most of the soil and plant parameters had a medium to high range of influence(20 to 90 m)and varied greatly within the field.Kriged maps of plant and soil parameters also showed spatial variations and were aligned with descriptive statistics and correlations.Quantification of soil spatial variability within potato fields can assist in measuring yield-limiting soil characteristics to establish management zones for variable rate fertilization for optimum tuber yield and low environmental impact.展开更多
Orchard target-oriented fertilizing with on-board sensor technology can improve fertilizer efficiency and reduce environmental pollution.Photoelectric sensors are widely used for object detection because of their low ...Orchard target-oriented fertilizing with on-board sensor technology can improve fertilizer efficiency and reduce environmental pollution.Photoelectric sensors are widely used for object detection because of their low cost and fast response time.This paper presents a Wolfberry tree dual-model detection method and the design of an orchard target-oriented variable-rate fertilization system based on photoelectric sensors.The dual-model detection method includes the Trunk Detection Model(TDM)and Canopy Detection Model(CDM),which can be applied for Wolfberry orchards at the green cluster and mature stages,respectively.A target-oriented fertilization system was designed using the dual-model method,and tested in the lab and Chinese Wolfberry orchard.The laboratory test results showed that the average center offset distances on the condition of detecting trunks,continuous canopies,and discontinuous canopies were 4.1 cm,9.1 cm and 13.1 cm,respectively.The system could ignore the signals from canes when their diameters were less than 16 mm,and also could determine the gaps within a tree when they were less than 21 cm.The orchard test results showed that the system accomplished target-oriented fertilization 95 times for 92 trees at the mature stage.The results indicated that the dual-model detection method could be used for Wolfberry trees or other trees with similar canopy changes at different growth stages.展开更多
Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,...Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,uneven fertilizer-spreading uniformity is becoming a key factor restricting the application of centrifugal fertilizer spreaders.Accordingly,the particle application characteristics and variation laws for centrifugal VRF spreaders with multi-pass overlapped spreading needs to be urgently explored,in order to improve their distribution uniformity and working accuracy.In this study,the working performance of a self-developed centrifugal VRF spreader,based on real-time growth information of rice and wheat,was investigated and tested through the test methods of using the collection trays prescribed in ISO 5690 and ASAE S341.2.The coefficient of variation(CV)was calculated by weighing the fertilizer mass in standard pans,in order to evaluate the distribution uniformity of spreading patterns.The results showed that the effective application widths were 21.05,22.58 and 23.67 m for application rates of 225,300 and 375 kg/ha,respectively.The actual fertilizer application rates of multi-pass overlapped spreading were generally higher than the target rates,as well as the particle distribution CVs within the effective spreading widths were 11.51,9.25 and 11.28%for the respective target rates.Field test results for multi-pass overlapped spreading showed that the average difference between the actual and target application was 4.54%,as well as the average particle distribution CV within the operating width was 11.94%,which met the operation requirements of particle transverse distribution for centrifugal fertilizer spreaders.The results and findings of this study provide a theoretical reference for technical innovation and development of centrifugal VRF spreaders and are of great practical and social significance for accelerating their application in implementing precision agriculture.展开更多
It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of ...It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of soil analysis for NPK determination using the digital soil test kit.NPK determination procedure with a digital soil test kit was undefined for oil palm.Furthermore,the digital soil test kit determines the passage of light through an opaque medium of soil solution with a specified reagent.Therefore,environmental light may interfere leading to wrong results of NPK measurement.Likewise,this equipment was non-incorporable with the controller of any VRT fertilizer applicator.In this research,these issues were addressed and the NPK measurement procedure was defined for oil palm plantation by modifying the‘soil to water’ratio in sample soil solution with an optimum environmental light range of 18-23 W/m^(2).‘Soil to water’ratios were found for nitrogen,phosphorus and potassium as 0.31 to 5.00,1.00 to 5.00 and 4.50 to 5.00,respectively to fit the requirement of NPK for oil palm in the prescribed range of the equipment.Validation study of modified digital soil test kit showed that 91.7%N,89.6%P and 93.8%K results of modified digital soil test kit were matched with analytical laboratory method.Thus,the reliability of NPK results using digital soil test kit was enhanced,making the kit incorporable with the controller of variable rate fertilizer applicator through remote monitoring based data acquisition system.The outcome of this research can be used in the development of an IoT network data fusion for dynamic assessment of the NPK variation in the soil and nutrient management in oil palm plantations.展开更多
文摘This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs （about 20%）. This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field.
基金We acknowledge that the research is supported by the National Key Technology Research and Development Program(No.2012BAK17B15).
文摘This paper presented a novel variable rate fertilization system based on the method of adjusting the active feed-roll length of a fluted roller.The feasibility of this method was discussed using analysis of the fluted roller model.One seed drill produced by Kuhn Company(France),which could sow and fertilize simultaneously,was used as a test platform to implement the mechanical structure of variable rate fertilization.The design methods for the variable rate fertilization mechanical structure and actuator were introduced in detail.A low-cost and stable embedded support decision subsystem and corresponding software were developed.The support decision subsystem is based on grid management.Each grid field cell contains information about corresponding spatial position and fertilizer application rate.A SpatiaLite database was employed to solve the spatial location search and spatial data query.Experiments were conducted to evaluate the fertilization uniformity and dynamic response time.The average value of coefficient of variation is 8.4%in five different active feed-roll lengths which reflects good uniformity.The dynamic response times for the adjustment of variable rate fertilization system from 204 kg/hm^(2) to 319 kg/hm^(2) and 319 kg/hm^(2) to 204 kg/hm^(2) are about 4.2 s.The results suggest that the variable rate fertilization system performs well in dynamic adjustment and stability.
基金The authors express appreciation for the financial support provided by National Key Technologies R&D Program of China(No.2017YFD0700305 and No.2016YFD0200600-2016YFD0200602-4)Fundamental Research Funds for Central Non-profit Scientific Institution(S201712).
文摘The key technical problem of variable rate fertilization system based on spectrum information was precise variable fertilization in certain area according to the acquired spectrum information.Hysteretic fertilizing is a critical problem in most of current fertilizer equipment.Hysteresis model was built and analyzed in this study to improve the system.Fertilizing tests were conducted on different wheat breeds and the results were analyzed.The tests showed that variable rate fertilization had obvious hysteresis phenomenon with the maximum lag distance of 3.82 m,the minimum lag distance of 1.73 m and average of 3.06 m.Hysteresis phenomenon of the variable rate fertilization system was obviously decreased when implanting a correction time of 2.04 s with the maximum lag distance of 0.61 m.Variable effects varied by different wheat breeds.Variable rate fertilization had an advantage of improving spatial differences of Yangmai-23,and the spatial variability of which decreased by 14.23%.In the small test area,the amount of fertilizer in Zhenmai-168 decreased by 2.84 kg,while the amount of which in Yangmai-23 increased by 3.83 kg.Yield of Zhenmai-168 in small area was lower than that in traditional pattern,but the condition of Yangmai-23 was on the contrary.Valuable information for increasing performance of fertilization in variable rate fertilization system was provided in this paper.
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(No.31401284)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2014BAD06B03).
文摘In order to improve soil fertility and fertilizer utilization,a subsoiling variable rate fertilization machine based on conservation tillage and precision agriculture was designed and tested.The relationship between suspension parameters and penetrating distance was analyzed,and a matching model between fertilizing quantity and penetrating distance was established.The variable rate fertilization control machine was developed based on an Advantech PCM-9363 industrial control mainboard.The machine operates under two patterns:DGPS-based positioning and straight-line path positioning based on a planar coordinate system.This machine can perform on-demand fertilization according to the spatial differences in soil nutrients and the prescription maps pre-set before the operation.Field experiments showed the machine has a subsoiling stability of 92.5%,a soil breaking rate of 61.1%,a maximum positioning relative error of 2.68%and a maximum variable rate fertilization error of 3.89%.The subsoiling performance and variable rate fertilization indices of this machine satisfy the requirements of GB/T24675.2-2009.The tested indices meet the national and industrial standards and satisfy the design requirements.The findings of the research can be used as the structural design of the subsoiling variable rate fertilization machine.
文摘Potato is one of the key crops for ensuring food security and can be a potential substitute for cereal crops due to its high yielding nature and nutritional value.Crop nutrient management practices within potato fields are implemented uniformly without considering crop requirements and soil variability,causing uneven and low yield.However,yield can be increased by identifying growth and yield-limiting factors.Geospatial tools are robust and effective in identifying the spatial variations within the field.Proximal sensing allows quick analysis of soil and plant characteristics,decreases the need for laborious and expensive soil and plant sampling,and strengthens precision agriculture techniques.The aim of the study was to quantify the soil spatial variability and identify potato crop growth and yield limiting factors for the optimization of inputs.Two fields were selected in the subtropical region of Pakistan(Koont,Rawalpindi),and each field was cultivated with two different potato varieties.A grid sampling approach was developed to collect soil samples and tuber yields.The soil was tested for nitrogen(N),phosphorus(P),potassium(K),pH,electrical conductivity(E.C),temperature,and moisture content(M.C)by using a soil proximal sensor.Normalized difference vegetation index(NDVI)was recorded using a handheld GreenSeeker,and chlorophyll was estimated using a chlorophyll meter.Descriptive statistics and correlation analysis for soil and crop parameters were performed in Minitab 21,while geostatistical analysis was performed in Arc Map 10.8 to show spatial variability and to generate kriged maps of different soil properties.The coefficient of variation of soil properties and plant parameters showed moderate to high variability within the field,except for pH and temperature.The correlation matrix suggested that N,P,K,E.C.,chlorophyll,NDVI,plant height,and leaf area had a significant relationship with potato yield.Most of the soil and plant parameters had a medium to high range of influence(20 to 90 m)and varied greatly within the field.Kriged maps of plant and soil parameters also showed spatial variations and were aligned with descriptive statistics and correlations.Quantification of soil spatial variability within potato fields can assist in measuring yield-limiting soil characteristics to establish management zones for variable rate fertilization for optimum tuber yield and low environmental impact.
基金This work was supported by Shaanxi Science and Technology Projects(2017KJXX-54 and 2014KTCL02-15)Science and Technology Project of Northwest A&F University(Z222021560)the"Young Faculty Study Abroad Program"of Northwest A&F University Scholarship Fund.
文摘Orchard target-oriented fertilizing with on-board sensor technology can improve fertilizer efficiency and reduce environmental pollution.Photoelectric sensors are widely used for object detection because of their low cost and fast response time.This paper presents a Wolfberry tree dual-model detection method and the design of an orchard target-oriented variable-rate fertilization system based on photoelectric sensors.The dual-model detection method includes the Trunk Detection Model(TDM)and Canopy Detection Model(CDM),which can be applied for Wolfberry orchards at the green cluster and mature stages,respectively.A target-oriented fertilization system was designed using the dual-model method,and tested in the lab and Chinese Wolfberry orchard.The laboratory test results showed that the average center offset distances on the condition of detecting trunks,continuous canopies,and discontinuous canopies were 4.1 cm,9.1 cm and 13.1 cm,respectively.The system could ignore the signals from canes when their diameters were less than 16 mm,and also could determine the gaps within a tree when they were less than 21 cm.The orchard test results showed that the system accomplished target-oriented fertilization 95 times for 92 trees at the mature stage.The results indicated that the dual-model detection method could be used for Wolfberry trees or other trees with similar canopy changes at different growth stages.
基金the Jiangsu Agricultural Science and Technology Innovation Fund(Grant No.CX(23)3029)the Natural Science Foundation of Jiangsu Province(Grant No.BK20210410)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.YDZX2024033)the National Key Project of Research and Development Program(Grant No.2023YFD200100102,2023YFD200100204).
文摘Environmental impacts and economic demands are driving the development of variable rate fertilization(VRF)technology for precision agriculture.Despite the advantages of a simple structure,low cost and high efficiency,uneven fertilizer-spreading uniformity is becoming a key factor restricting the application of centrifugal fertilizer spreaders.Accordingly,the particle application characteristics and variation laws for centrifugal VRF spreaders with multi-pass overlapped spreading needs to be urgently explored,in order to improve their distribution uniformity and working accuracy.In this study,the working performance of a self-developed centrifugal VRF spreader,based on real-time growth information of rice and wheat,was investigated and tested through the test methods of using the collection trays prescribed in ISO 5690 and ASAE S341.2.The coefficient of variation(CV)was calculated by weighing the fertilizer mass in standard pans,in order to evaluate the distribution uniformity of spreading patterns.The results showed that the effective application widths were 21.05,22.58 and 23.67 m for application rates of 225,300 and 375 kg/ha,respectively.The actual fertilizer application rates of multi-pass overlapped spreading were generally higher than the target rates,as well as the particle distribution CVs within the effective spreading widths were 11.51,9.25 and 11.28%for the respective target rates.Field test results for multi-pass overlapped spreading showed that the average difference between the actual and target application was 4.54%,as well as the average particle distribution CV within the operating width was 11.94%,which met the operation requirements of particle transverse distribution for centrifugal fertilizer spreaders.The results and findings of this study provide a theoretical reference for technical innovation and development of centrifugal VRF spreaders and are of great practical and social significance for accelerating their application in implementing precision agriculture.
基金This research was supported by Universiti Putra Malaysia in coordination of United Melaka Bhd.(UMB).
文摘It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of land.Colorimetric method is a suitable and fast solution of soil analysis for NPK determination using the digital soil test kit.NPK determination procedure with a digital soil test kit was undefined for oil palm.Furthermore,the digital soil test kit determines the passage of light through an opaque medium of soil solution with a specified reagent.Therefore,environmental light may interfere leading to wrong results of NPK measurement.Likewise,this equipment was non-incorporable with the controller of any VRT fertilizer applicator.In this research,these issues were addressed and the NPK measurement procedure was defined for oil palm plantation by modifying the‘soil to water’ratio in sample soil solution with an optimum environmental light range of 18-23 W/m^(2).‘Soil to water’ratios were found for nitrogen,phosphorus and potassium as 0.31 to 5.00,1.00 to 5.00 and 4.50 to 5.00,respectively to fit the requirement of NPK for oil palm in the prescribed range of the equipment.Validation study of modified digital soil test kit showed that 91.7%N,89.6%P and 93.8%K results of modified digital soil test kit were matched with analytical laboratory method.Thus,the reliability of NPK results using digital soil test kit was enhanced,making the kit incorporable with the controller of variable rate fertilizer applicator through remote monitoring based data acquisition system.The outcome of this research can be used in the development of an IoT network data fusion for dynamic assessment of the NPK variation in the soil and nutrient management in oil palm plantations.
