Canopy shaking is one of the most commonly used techniques for mechanical harvesting of citrus fruits in orange juice industry.However,tree damage and low harvesting efficiency are the top concerns of growers in adopt...Canopy shaking is one of the most commonly used techniques for mechanical harvesting of citrus fruits in orange juice industry.However,tree damage and low harvesting efficiency are the top concerns of growers in adopting the existing harvesting equipment on a large scale.The purpose of this research was to develop a novel canopy shaking system to minimize tree damage and maximize fruit removal for mechanical citrus harvesting.In this study,a two-section canopy shaker composing of top and bottom shaking systems mounted on two rotating drums was proposed and developed.It was configured with two sets of flexible bow-shaped shaking rods in a staggered distribution,which can shake the top and bottom zones of the tree canopy independently.The shaking system was designed based on a linked crank-rocker mechanism.Kinematic simulation analysis was conducted to verify the quick return characteristics and differential properties of this mechanism.Vibration test showed that the frequency of the shaking rod could be adjusted within a range of 1.1-8.8 Hz related to hydraulic motor speeds.The field tests of the shaking system with an average frequency of 4.7 Hz achieved a fruit removal percentage of 82.6%and tree damage rate of 5.4%under a tractor speed of 3 km/h.By contrast,the combined shaking frequency of 4.7 Hz&4.1 Hz of the canopy shaker produced less tree damage with a percentage of 3.9%.This study indicated that the two-section canopy shaker with an optimized frequency combination could be adaptable to the different zones of the tree canopy,and obtain lower tree damage and higher fruit removal percentage.展开更多
Mechanized harvesting technologies with shaking systems for fruit industry have been widely investigated and significantly developed over the past several decades which were presented by a large amount of literature.T...Mechanized harvesting technologies with shaking systems for fruit industry have been widely investigated and significantly developed over the past several decades which were presented by a large amount of literature.This paper reviews the research and development progress of mechanized harvesting of fruits systematically with a focus on the theoretical study,fruit crop variety,shaking system categories,abscission chemical agents,and their actual applications.Based on the comprehensive review,mechanized harvesting systems for different fruit crops appear multifarious shaking modes with various vibratory mechanisms and structural dimensions.Major advantages in the development of fruit mechanical harvesting with effective vibratory patterns and catching frames provide a series of economic and agronomic benefits,such as reducing labor costs,promoting standardized planting,and increasing productivity.However,fruit injury and tree damage are the main reasons why mechanical shaking systems are rarely used for fresh fruit harvesting because of tenderness and frangibility of the fruit crops.Therefore,more efforts should be concentrated on the innovative shake-and-catch system with suitable frequency and amplitude to achieve low fruit damage or even nondestructive harvesting for fresh fruit market.This overview summarized the advantages and bottlenecks of these shaking systems for fruit harvesting and proposed the challenges and some constructive prospective viewpoints aimed at the major issues of mechanical harvesting techniques.In addition,employing sorting technologies to classify the postharvest fruits provide a new direction for the further development of mechanized harvesting in high-value fruit crops,as well as bring more benefits to growers and increase their interest in equipment investment on the mechanical shaking harvester for the fruit industry.展开更多
Canopy shaking system is one of the research hotspots for large-scale mechanized fruits harvesting.Shaking rods considered as one of the essential components of canopy shaker are responsible for transferring mechanica...Canopy shaking system is one of the research hotspots for large-scale mechanized fruits harvesting.Shaking rods considered as one of the essential components of canopy shaker are responsible for transferring mechanical energy from shaking mechanism to different regions of tree canopy.This transfer depends on the characteristics of the shaking rods that directly strike the tree canopy.In order to evaluate the effects of the shaking rods on tree damage level and fruit removal percentage,three kinds of shaking rods with different materials or shapes were selected.Based on the results of bending deformation tests,it was proven that the rigid shaking rod(R_(1))with the material of Polyvinyl Chloride(PVC)did more resistance against producing bending deformation in comparison with the other two types of shaking rods with the material of Polyamide Nylon 12(PA).By contrast,the position close to the free end of the flexible shaking rod was easier to be deformed by less external force.In addition,dynamic analysis and vibration performance tests indicated that the rigid shaking rod could produce stronger vibration with higher shaking frequency of 4.8 Hz and maximum acceleration of 31.4 m/s^(2).Finally,the results of field trials indicated that the flexible bow-shaped shaking rod(R_(3))has a better widespread performance to achieve comparative higher fruit removal percentage up to 82.6%while producing lower tree damage rate of 5.36%.This study demonstrates that the materials or shapes of the shaking rod could significantly influence the fruit detachment rate and tree damage level.This study would provide an essential reference for the application of shaking rods for canopy shaker.展开更多
Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate spra...Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate sprayer parameters for kiwifruit trees,the vertical distribution profiles of the applied liquid spray were examined in this study.The effects of spray fan speed(SFS),spray pressure(SP)and spray distance(SD)on the distributions of the sprayed liquid in the vertical profiles were studied.Combined actions of the above parameters were systematically analysed using the quadratic general rotary design test method.Regression equations for the spray liquid distributions and working factors are presented.Field confirmation experiments were carried out to optimize the parameters.Data analysis showed that the optional sprayer working parameters are those of Group 3,with an SFS equal to 1900 r/min and SP equal to 3.25 MPa.The results of this study provide a reference for future applications of this type of axial air-assisted sprayer in kiwifruit orchards.展开更多
The Clarivate Analytics Journal Citation Reports(JCR)and Web of Science(WoS)platforms are arguably the most influential journal citation/metric databases worldwide.Journals must first be indexed in the WoS Core Collec...The Clarivate Analytics Journal Citation Reports(JCR)and Web of Science(WoS)platforms are arguably the most influential journal citation/metric databases worldwide.Journals must first be indexed in the WoS Core Collection(CC)before being indexed in the JCR.The JCR and WoS platform are separate Clarivate Analytics products,but the JCR is included in the WoS platform for organizations that purchase both databases.The analysis for this study focused on citation data reported in the 2017 JCR(based on 2016 citation data)and other data reported in the WoS CC up to 2016.A total of 14 journals are indexed in the 2017 JCR agricultural engineering category;however,only 13 journals are analyzed in this because one journal was listed by mistake.Six of the 13 journals are published by large for-profit publishers(i.e.,Elsevier B.V.or Springer Verlag)and the other seven are published by respective professional societies.The journals were analyzed as a function of type(specialty versus comprehensive),type of publisher and publication frequency,metrics such as the Journal Impact Factor(JIF),volumes of articles published by year and journal,and the source institutions and countries of published articles.Bioenergy-and industrial crop-focused journals included in the 2017 JCR agricultural engineering category manifest the strongest overall metrics,as evidenced by relatively high JIF scores:Bioresource Technology(4.917),Biomass and Bioenergy(3.219)and Industrial Crops and Products(3.181).In contrast,the highest JIF reported in the 2017 JCR for a comprehensive agricultural engineering journal was 2.044 for Biosystems Engineering.During 2006 to 2016,the number of articles indexed in the Core Collection for the JCR agricultural engineering category rose from 1,124 to 4,078,an increase of 263%.Over 70% of the total articles published in 2016 were published in the three bioenergy-or industrial-crop focused journals.The top three countries that published the highest levels of WoS Core Collection agricultural engineering articles in 2016 were China(1132),United States(669)and Brazil(474).The similar top publishing institutions were the United States Department of Agriculture(USDA;136),Chinese Academy of Sciences(CAS;136)and Indian Council for Scientific and Industrial Research(CSIR;79).The results of the study also show that publishing by Chinese scientists in the 13 journals indexed in the JCR Agricultural Engineering(AE)category is rapidly increasing,with seven research institutions ranked in the global top 20 in 2016,based on studies published in journals indexed in the JCR agricultural engineering category.The analysis also reveals that the specialty journals(e.g.,the three bioenergy-focused journals)are not directly comparable with the comprehensive agricultural engineering journals and should potentially be excluded from future versions of the JCR and WoS CC AE categories.展开更多
基金Additional financial supports are also provided from the National Key R&D Program of China“the 13th Five-Year Plan”(Program No.2016YFD0700503)Major Program of Cooperative Innovation for Yangling Demonstration Zone(Program No.2016CXY-20)the Shaanxi Provincial Agricultural Technology Program of Innovation and Development(Program No.2016NY-127).
文摘Canopy shaking is one of the most commonly used techniques for mechanical harvesting of citrus fruits in orange juice industry.However,tree damage and low harvesting efficiency are the top concerns of growers in adopting the existing harvesting equipment on a large scale.The purpose of this research was to develop a novel canopy shaking system to minimize tree damage and maximize fruit removal for mechanical citrus harvesting.In this study,a two-section canopy shaker composing of top and bottom shaking systems mounted on two rotating drums was proposed and developed.It was configured with two sets of flexible bow-shaped shaking rods in a staggered distribution,which can shake the top and bottom zones of the tree canopy independently.The shaking system was designed based on a linked crank-rocker mechanism.Kinematic simulation analysis was conducted to verify the quick return characteristics and differential properties of this mechanism.Vibration test showed that the frequency of the shaking rod could be adjusted within a range of 1.1-8.8 Hz related to hydraulic motor speeds.The field tests of the shaking system with an average frequency of 4.7 Hz achieved a fruit removal percentage of 82.6%and tree damage rate of 5.4%under a tractor speed of 3 km/h.By contrast,the combined shaking frequency of 4.7 Hz&4.1 Hz of the canopy shaker produced less tree damage with a percentage of 3.9%.This study indicated that the two-section canopy shaker with an optimized frequency combination could be adaptable to the different zones of the tree canopy,and obtain lower tree damage and higher fruit removal percentage.
基金appreciate the funding from the National Key R&D Program of China“the 14th Five-Year Plan”(No.2020YFD1000100)the National Natural Science Foundation of China(No.52205284)This work was also supported by the Fundamental Research Funds for the Central Universities(No.SWU119015).
文摘Mechanized harvesting technologies with shaking systems for fruit industry have been widely investigated and significantly developed over the past several decades which were presented by a large amount of literature.This paper reviews the research and development progress of mechanized harvesting of fruits systematically with a focus on the theoretical study,fruit crop variety,shaking system categories,abscission chemical agents,and their actual applications.Based on the comprehensive review,mechanized harvesting systems for different fruit crops appear multifarious shaking modes with various vibratory mechanisms and structural dimensions.Major advantages in the development of fruit mechanical harvesting with effective vibratory patterns and catching frames provide a series of economic and agronomic benefits,such as reducing labor costs,promoting standardized planting,and increasing productivity.However,fruit injury and tree damage are the main reasons why mechanical shaking systems are rarely used for fresh fruit harvesting because of tenderness and frangibility of the fruit crops.Therefore,more efforts should be concentrated on the innovative shake-and-catch system with suitable frequency and amplitude to achieve low fruit damage or even nondestructive harvesting for fresh fruit market.This overview summarized the advantages and bottlenecks of these shaking systems for fruit harvesting and proposed the challenges and some constructive prospective viewpoints aimed at the major issues of mechanical harvesting techniques.In addition,employing sorting technologies to classify the postharvest fruits provide a new direction for the further development of mechanized harvesting in high-value fruit crops,as well as bring more benefits to growers and increase their interest in equipment investment on the mechanical shaking harvester for the fruit industry.
基金the funding from the National Key R&D Program of China“the 13th Five-Year Plan”(Program No.2016YFD0700503)Major Program of Cooperative Innovation for Yangling Demonstration Zone(Program No.2016CXY-20)the Shaanxi Provincial Agricultural Technology Program of Innovation and Development(Program No.2016NY-127).We also wish to thank the China Scholarship Council for providing the financial support to the first author for conducting his collaborative doctoral research in the CREC at the University of Florida.The authors are grateful to the National Institute of Food and Agriculture(Project No.FLA-LAL-005354)for providing the funding for this research.Also,we thank the critical comments and suggestions from the anonymous reviewers for improving the manuscript.
文摘Canopy shaking system is one of the research hotspots for large-scale mechanized fruits harvesting.Shaking rods considered as one of the essential components of canopy shaker are responsible for transferring mechanical energy from shaking mechanism to different regions of tree canopy.This transfer depends on the characteristics of the shaking rods that directly strike the tree canopy.In order to evaluate the effects of the shaking rods on tree damage level and fruit removal percentage,three kinds of shaking rods with different materials or shapes were selected.Based on the results of bending deformation tests,it was proven that the rigid shaking rod(R_(1))with the material of Polyvinyl Chloride(PVC)did more resistance against producing bending deformation in comparison with the other two types of shaking rods with the material of Polyamide Nylon 12(PA).By contrast,the position close to the free end of the flexible shaking rod was easier to be deformed by less external force.In addition,dynamic analysis and vibration performance tests indicated that the rigid shaking rod could produce stronger vibration with higher shaking frequency of 4.8 Hz and maximum acceleration of 31.4 m/s^(2).Finally,the results of field trials indicated that the flexible bow-shaped shaking rod(R_(3))has a better widespread performance to achieve comparative higher fruit removal percentage up to 82.6%while producing lower tree damage rate of 5.36%.This study demonstrates that the materials or shapes of the shaking rod could significantly influence the fruit detachment rate and tree damage level.This study would provide an essential reference for the application of shaking rods for canopy shaker.
基金The authors acknowledge that this work was financially supported by the National Key Research and Development Program(No.2016YFD0200700)the National Key R&D Program of China“the 13th Five-Year Plan”(Grant No.2016YFD0700503)the Science and Technology Project of Shaanxi Province.Also,we thank the critical comments and suggestions from the anonymous reviewers for improving the manuscript.
文摘Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate sprayer parameters for kiwifruit trees,the vertical distribution profiles of the applied liquid spray were examined in this study.The effects of spray fan speed(SFS),spray pressure(SP)and spray distance(SD)on the distributions of the sprayed liquid in the vertical profiles were studied.Combined actions of the above parameters were systematically analysed using the quadratic general rotary design test method.Regression equations for the spray liquid distributions and working factors are presented.Field confirmation experiments were carried out to optimize the parameters.Data analysis showed that the optional sprayer working parameters are those of Group 3,with an SFS equal to 1900 r/min and SP equal to 3.25 MPa.The results of this study provide a reference for future applications of this type of axial air-assisted sprayer in kiwifruit orchards.
文摘The Clarivate Analytics Journal Citation Reports(JCR)and Web of Science(WoS)platforms are arguably the most influential journal citation/metric databases worldwide.Journals must first be indexed in the WoS Core Collection(CC)before being indexed in the JCR.The JCR and WoS platform are separate Clarivate Analytics products,but the JCR is included in the WoS platform for organizations that purchase both databases.The analysis for this study focused on citation data reported in the 2017 JCR(based on 2016 citation data)and other data reported in the WoS CC up to 2016.A total of 14 journals are indexed in the 2017 JCR agricultural engineering category;however,only 13 journals are analyzed in this because one journal was listed by mistake.Six of the 13 journals are published by large for-profit publishers(i.e.,Elsevier B.V.or Springer Verlag)and the other seven are published by respective professional societies.The journals were analyzed as a function of type(specialty versus comprehensive),type of publisher and publication frequency,metrics such as the Journal Impact Factor(JIF),volumes of articles published by year and journal,and the source institutions and countries of published articles.Bioenergy-and industrial crop-focused journals included in the 2017 JCR agricultural engineering category manifest the strongest overall metrics,as evidenced by relatively high JIF scores:Bioresource Technology(4.917),Biomass and Bioenergy(3.219)and Industrial Crops and Products(3.181).In contrast,the highest JIF reported in the 2017 JCR for a comprehensive agricultural engineering journal was 2.044 for Biosystems Engineering.During 2006 to 2016,the number of articles indexed in the Core Collection for the JCR agricultural engineering category rose from 1,124 to 4,078,an increase of 263%.Over 70% of the total articles published in 2016 were published in the three bioenergy-or industrial-crop focused journals.The top three countries that published the highest levels of WoS Core Collection agricultural engineering articles in 2016 were China(1132),United States(669)and Brazil(474).The similar top publishing institutions were the United States Department of Agriculture(USDA;136),Chinese Academy of Sciences(CAS;136)and Indian Council for Scientific and Industrial Research(CSIR;79).The results of the study also show that publishing by Chinese scientists in the 13 journals indexed in the JCR Agricultural Engineering(AE)category is rapidly increasing,with seven research institutions ranked in the global top 20 in 2016,based on studies published in journals indexed in the JCR agricultural engineering category.The analysis also reveals that the specialty journals(e.g.,the three bioenergy-focused journals)are not directly comparable with the comprehensive agricultural engineering journals and should potentially be excluded from future versions of the JCR and WoS CC AE categories.
