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1.
Automatic section control (ASC) has been readily adopted by US producers on sprayers because it can improve operator productivity and decrease overlap or input usage leading to economic savings while reducing environmental impacts. However, there is limited knowledge about nozzle flow dynamics when shutting ON/OFF of boom-sections or nozzles and the possible impact on application accuracy. Therefore, an investigation was conducted to evaluate system response in managing real-time nozzle off-rate and flow uniformity across the boom, for a typical agricultural sprayer using ASC. An 18.3-m sprayer was outfitted with commercially available individual nozzle and boom-section control. Tests were conducted to simulate sprayer moving out of point rows into a no-spray zone and then reentry into the spray zone by selecting two point row scenarios having 20° and 70° angles. Ten high frequency response pressure sensors were randomly mounted across the boom to measure nozzle pressure. The nozzle pressures were converted to nozzle flow, using the manufacturers pressure versus flow relationship, to calculate nozzle flow rate delay time, settling time, percent off-rate (percent difference between actual and target nozzle flow rate) and nozzle flow uniformity (CV), considering only ON boom-sections. Auto-boom scenarios were conducted with and with-out flow compensation while auto-nozzle scenarios were conducted without flow compensation. Results indicated that nozzle flow rate settling time varied from 0.4 to 14.4 s and nozzle off-rate between 36.6% and +28.7% for 70° point row auto-boom tests when exiting and reentering point rows. When exiting point rows, over-application occurred whereas reentry resulted in under-application during flow compensated tests. Nozzle flow uniformity (CV) were more than 50% for a short duration (<1.0 s) when reentering point rows, during all tests. Compensation testing for 20° point row reentry highlighted the constraint of the control system to respond to certain situations where feedback response times could not match target rates rapidly set for the controller. Overall results indicated that system response time can impact nozzle off-rate and can vary with point row angle.  相似文献   

2.
The wild blueberry industry is spending over $80 million CAD per year on agrochemicals for 93 000 ha under production in North America. A pressing need to reduce agro-chemical usage and production cost has resulted in the development of a smart sprayer for spot-application of agrochemicals in wild blueberry fields. This paper encompasses the economic analysis to determine the potential savings for spot-applications of agrochemicals using a smart sprayer. The economic analysis compared the smart sprayer with two other commercially available sprayers (basic and swath control). The swath control sprayer and smart sprayer both featured GPS auto-steer and boom section control to reduce over-spray in already applied areas based on GPS position. The basic sprayer used a foam marker for guidance with no swath control management. The smart sprayer featured a machine vision system that automatically detected target areas in the field further reducing agrochemical input by shutting individual nozzles off in non-target areas in the field. The cost analysis was performed to compare the different features of the sprayer technologies, i.e., base sprayer, additional technology, training, usage, repair and maintenance. The additional components installed on the smart sprayer were justified in terms of agrochemicals/water savings via spot-applications, tractor fuel and operator’s time. The application total cost was $2052 ha?1 using the basic sprayer, $1799 ha?1 using the swath control sprayer, and $1138 ha?1 using the smart sprayer over a 2 year production cycle of the selected fields that were used in this study. The payback period ranged from 2.0 years (60 ha field size) to 9.8 years (20 ha field size) using the swath control sprayer. The payback period ranged from 11 months (60 ha field size) to 3.5 years (20 ha field size) when using the smart sprayer. Results revealed that the smart sprayer had significant advantage from both an environmental and economic perspective over the other two sprayers.  相似文献   

3.
[目的]比较不同喷雾器以及喷头对农药有效利用率和施药效率的影响。[方法]采用诱惑红作为农药喷雾的示踪剂,分析了4种喷雾器及喷头在田间喷雾下的雾滴大小、施药效率、叶片农药的沉积回收率和雾滴田间分布均匀性。[结果]农药的有效利用率方面表现为电动喷雾器>机动喷雾器>手动喷雾器>手动弥雾器;施药效率方面表现为机动喷雾器>电动喷雾器>手动弥雾器>手动喷雾器;农药雾滴田间分布均匀性方面表现为电动喷雾器最好,其余都较差。[结论]为新型植保器械的推广应用提供了理论依据。  相似文献   

4.
Vegetation indices (VI) obtained by optical sensors have a positive correlation with various attributes of cotton plant growth. This work is aimed at evaluating the variable rate application of plant growth regulator (PGR) and fruit ripener on zones defined by VI and penological measurements using a sprayer equipped with a relatively low cost electronic flow controller on the height, percentage of open fruits, yield and net income. The work was done in a 92 ha field during crop seasons 2012/2013 and 2013/2014, and in a 202 ha field, during the crop season 2014/2015. Two spray applications were made using variable rate technology (VRT) of the PGR and one fruit ripener, in both harvest seasons, according to three VI classes formed by a previous mapping. The uniformity of the cotton height and opened fruits contribute to a similar yield across zones. Uniform plant height facilitates cotton harvest. The ripener helps to ensure all the cotton is ready to be harvested at the same time. In this trial, use of VRT technique to manage the PGR and fruit ripener application increased net income by US$152.28 ha?1, but this estimate is based on yields that are not statistically significantly different from the control. This research confirms that PGR and fruit ripener can be sufficiently managed with an electronic flow controller to result in more uniform cotton plant height and yields within fields, but it leaves open the question of whether VRT PGR is profitable even with the lower cost electronic flow controller.  相似文献   

5.
Pesticide application is an essential practice on many U.S. crop farms. Off-rate pesticide application errors may result from velocity differential across the spray boom while turning, pressure fluctuations across the spray boom, or changes in boom-to-canopy height due to undulating terrain. The sprayer path co-ordinates and the status (on or off) of each boom control section were recorded using the sprayer control console which provided map-based automatic boom section control. These data were collected for ten fields of varying shapes and sizes located in central Kentucky. In order to estimate potential errors resulting from sprayer turning movements, a method was developed to compare the differences in application areas between spray boom control sections. The area covered by the center boom control section was considered the “target rate area” and the difference in these areas and the areas covered by remaining control sections were compared to estimate application rate errors. The results of this analysis conducted with sprayer application files collected from ten fields, many containing impassable grassed waterways, indicated that a substantial portion of the fields (6.5–23.8%) could have received application in error by more than ±10% of the target rate. Off-rate application errors exceeding ±10% of the target rate for the study fields tended to increase as the average turning angles increased. The implication of this is that producers may be unintentionally applying at off-label rates in fields of varying shapes and sizes where turning movements are required.  相似文献   

6.
Evaluation of ultrasonic sensor for variable-rate spray applications   总被引:2,自引:0,他引:2  
Automatic variable-rate sprayers require accurate measurement of canopy size. An estimate of canopy size is made by measuring the distance to the canopy at several elevations above the ground; an ultrasonic sensor was used to determine canopy distance in this study. It is sometimes necessary to conduct spray operations during harsh operating conditions. In this study ultrasonic sensors were subjected to simulated environmental and operating conditions to determine their durability and accuracy. Conditions tested included exposure to extended cold, outdoor temperatures, cross winds, temperature change, dust clouds, travel speeds and spray cloud effects. The root mean square (RMS) error in a series of measurements of the distance to a simulated plant canopy was used to test for significant difference among treatments. After exposure to outdoor cold conditions for 4 months, the RMS error in distance measured by the ultrasonic sensor increased from 3.31 to 3.55 cm, which was not statistically significant. Neither the presence of dust cloud nor the changes in cross-wind speeds over a range from 1.5-7.5 m/s had significant effects on the mean RMS errors. Varying sensor travel speed from 0.8 to 3.0 m/s had no significant influence on sensor detection distances. Increasing ambient temperature from 16.7 to 41.6 °C reduced the detection distance by 5.0 cm. The physical location of the spray nozzle with respect to the ultrasonic sensor had a significant effect on mean RMS errors. The mean RMS errors of sensor distance measurements ranged from 2.3 to 83.0 cm. The RMS errors could be reduced to acceptable values by proper controlling the sensor/spray nozzles spacing on a sprayer. In addition, multiple-synchronized sensors were tested for their measurement stability and accuracy (due to possible cross-talk errors) when mounted on a prototype sprayer. It was found that isolating the pathway of the ultrasonic wave of each sensor reduced detecting interference between sensors during multiple sensor operation. Test methods presented herein may be useful in the design of standardized testing protocols for field use distance sensors.  相似文献   

7.
Pesticide application monitoring and long-term data recording in the field is typically the first step in fruit traceability. In a spray monitoring and guiding system, identification of the sprayer movement is a key part of technology. Although Global Navigation Satellite System (GNSS) is a widely used system to obtain location information, in an orchard/vineyard, especially one in which the trees/plants have tall and large canopies, the continuity and stability of the GNSS signal may decrease dramatically and lead to failure of guidance. A Radio Frequency Identification Devices (RFID) solution for identifying sprayer travel was proposed, and a spray monitoring and guiding system was designed based on this solution. In-lab system simulation test and field test results showed that the system could distinguish the travel direction of the sprayer, identify its location in the field, record flow rate information, calculate sprayed volume, and show all the above information on a computer screen in real-time when the RFID reader had successfully registered each RFID card. For the monitoring and guiding system with one antenna on each side, which required the cards and the antennas to be at the same height, the best relative position was found by placing the card parallel to the antenna. The results of tests in the field showed that an improved system with two antennas on each side, which only required the cards to be put in the band with a width of 0.26 m between the centers of the two antennas, worked better with the best antenna angle of 125° when the speed of the sprayer was less than 1.8 m/s.  相似文献   

8.
During variable rate operations, controller systems report information (as-applied files) about desired rates and real applied rates on georeferenced points along the machine tracks. These reports are useful for operation quality control but they have not been widely used to their potential. The goal of this study was to create a model to help analyzing as-applied files based on quantifying and locating off-rate errors and their probable related sources. The model calculates off-rate error at every point and classifies them as less than target rate, acceptable or over the target rate. Possible error sources are classified regarding three aspects: vehicle path position (inward, middle or outward), high rate change (step up or down) and vehicle acceleration or deceleration. A pulled type applicator (application 1) and a self-propelled applicator (application 2) were analyzed. An average of 30.6 % of the recorded points was considered application errors (10 % off the target rate). 70.5 % of them occurred on high rate change points on application 1 and 69.7 % on acceleration/deceleration points on application 2. The self-propelled applicator performed better during high transition rate than the pulled type which performed poorly when transition rate exceeded 10 %. The model determined the major and minor factors related to application error. It provided means to assess equipment limitations and its impact over the quality of application. The trials demonstrated its flexibility and how it can improve the use of as-applied files.  相似文献   

9.
10.
A computational fluid dynamics (CFD) model to simulate airflow from air-assisted orchard sprayers through pear canopies was validated for three different sprayers; single-fan (Condor V), two-fan (Duoprop) and four-fan sprayers (AirJet Quatt). The first two sprayers are widely used in Belgium and the latter one is a new design. Validation experiments were carried out in an experimental orchard (pcfruit, Velm, Belgium) in spring 2008. Ultrasonic anemometers were used to measure the time-averaged velocity components at different vertical positions before the tree and after the tree when the sprayers were driven through the orchard. The model was able to predict accurately the peak jet velocity, Um from all the sprayers considered at all distances from the sprayer centre and vertical positions. More than 95% of the local relative errors of Um were below 20%. Average relative errors, E, and root mean square errors, ERMS, were all less than 11.04% and 1.68 m s−1, respectively. The regions of high- (up to 18.0 m s−1 upstream) and low (down to 2.8 m s−1 downstream)-air velocity zones for all the sprayers were accurately predicted. The simulation results showed that the Condor V sprayer had a highly disturbed vertical jet velocity profile, especially at higher heights. The Duoprop sprayer had high jet velocities at the two-fan positions and lower jet velocity in between the two fans. Within the canopy height the AirJet Quatt sprayer showed a more uniform distribution of air than the other two sprayers except the minor peaks at the fan positions. These situations were all confirmed by the measurements.  相似文献   

11.
An essential part of the wild blueberry cropping system is the proper management of agrochemical inputs including herbicides, fungicides and insecticides. A machine vision system was developed and mounted on the rear sprayer boom 0.18 m in front of the sprayer nozzles capable of targeting the agrochemical application on an as-needed basis. The three-point hitch mounted sprayer featured 27 nozzles over a 13.7 m boom width and a storage tank capacity of 1135 l. Nine digital color cameras continually take images in real-time while computer software processes the images in 0.15 s to determine the target locations where the nozzles open and spray at speeds up to 1.77 m s?1. Two wild blueberry fields in central Nova Scotia were selected for smart sprayer performance testing with spot-application (SA) of agrochemical as compared to control and uniform application techniques. Chateau® herbicide was applied in a field with an infestation of hair cap moss. Spray droplet comparison showed moss patches were properly targeted using the smart sprayer. SA provided the same coverage performance as compared to uniform on the moss targets with herbicide application savings of 78.5% using the smart sprayer. Harvestable yield results were similar for all application tracks. TruPhos Magnesium and ZincMax foliar fertilizers were tank mixed with Bravo® and Proline® fungicides and applied to compare the difference of SA, control and uniform application. Results showed SA of foliar fertilizer and fungicide led to less premature leaf drop and increased the blueberry stem height, number of branches, stem diameter and fruit buds. SA of foliar fertilizer and fungicide also increased the percent of healthy wild blueberry plants by 57.8% and the harvestable yield by 137.8%. Fungicide application savings using the smart sprayer for SA were 11.6%.  相似文献   

12.
在果园管理工作中,病虫害防治是极其重要的一环。近些年,我国果园风送式喷雾机得到了巨大发展,有效提高了农药利用率,降低了农药对农作物的影响,减小了环境污染问题。本文阐述了果园风送喷雾机研究进程,分析了喷雾机风送系统,以期为我国果园风送喷雾机的研发提供参考。  相似文献   

13.
棉花是新疆兵团农业经济发展的重点和支柱产业,棉花重大病、虫、草害的防治是保证其稳产、高产、高效的重要措施之一。为克服现有机具工作效率低、农药有效利用率低等问题,研制了一种与大马力机车相配套的超宽幅喷杆式喷雾机。该机具主要由机架、动力系统、液压系统、展臂总成、等部件组成,设计的折叠机构、仿形机构和回弹机构有效的减轻了大型喷雾机在运输和工作时对障碍物的碰撞。田间试验表明:该机适用性强,行进灵活,在药箱压力0.5 MPa,喷嘴直径为2.0 mm,喷嘴流量为24 ml/s时,喷雾质量最佳,雾滴中径为57.845μm,雾滴均匀性为0.89,工作性能达到技术规范要求。  相似文献   

14.
温室弥雾机控制系统的设计   总被引:1,自引:0,他引:1  
为实现温室环境人机分离自动变量施药,设计基于Wi-Fi与模糊控制的自走式自动变量风送弥雾机。施药系统以STM32单片机为核心,在Eclipse开发环境下采用Socket编程技术实现移动端与弥雾机端双向通信。为满足施药技术要求,采用Mamdani模型制定施药控制规则,将虫害覆盖率和茄子冠层高度参数作为模糊控制模型的输入,根据施药控制规则自动控制电磁阀和继电器以调控喷雾流量和控制施药时间,共同完成弥雾机变量施药。通过流量测定、模糊控制及自动与手动弥雾的沉积试验对施药系统进行验证,结果表明:1)施药控制系统可根据占空比准确调控喷雾流量,且占空比与喷雾流量线性度较好,拟合度为R~2=0.996 4,满足该设计喷雾范围要求。2)采样点与喷头距离为1~3m时对单位面积雾滴有效沉积量影响显著,且随着茄子冠层高度的增大和蓟马覆盖率的提高均会使单位面积雾滴沉积量显著提高。3)自动弥雾与手动弥雾沉积量的相对误差不超过0.8%,可满足变量喷雾的实际需求。  相似文献   

15.
A technical–economic analysis was conducted on three different technological levels of spraying equipment for specialty crops, based on the results on precision spraying technologies reported in scientific literature. The application scenarios referred to general protection protocols against fungal diseases adopted in vineyards and apple orchards in Central-Southern Europe. The analysis evaluated the total costs of protection treatments (equipment + pesticide costs), comparing the use of conventional air-blast sprayers (referred to as L0), of on–off switching sprayers (L1), and of canopy-optimised distribution sprayers (L2). Pesticide savings from 10 to 35% were associated with equipment L1 and L2, as compared to L0. Within the assumptions made, on grapevines, the conventional sprayer L0 resulted in the most profitable option for vineyard areas smaller than 10 ha; from 10 ha to approximately 100 ha, L1 was the best option, while above 100 ha, the more advanced equipment L2 resulted in the best choice. On apple orchards, L0 was the best option for areas smaller than 17 ha. Above this value, L1 was more profitable, while L2 never proved advantageous. Finally, in a speculation on possible prospectives of precision spraying on specialty crops, the introduction of an autonomous robotic platform able to selectively target the pesticide on diseased areas was hypothesised. The analysis indicated that the purchase price that would make the robotic platform profitable, thanks to the assumed pesticide and labour savings over conventional sprayers, was unrealistically lower than current industrial cost. This study showed that, in current conditions, profitability cannot be the only driver for possible adoption of intelligent robotic platforms for precision spraying on specialty crops, while on–off and canopy-optimised technologies can be profitable over conventional spraying in specific conditions.  相似文献   

16.
喷雾方式对农药雾滴在水稻群体内沉积分布的影响   总被引:10,自引:1,他引:9  
【目的】分析喷雾方式对农药雾滴在水稻群体内沉积分布的影响,研究提出稻田合理的喷雾方式,提高稻田农药利用率。【方法】在水稻分蘖期、孕穗期和扬花期,用配有空心圆锥雾喷头的手动喷雾器叶面喷洒和配有气力式弥雾喷头的弥雾机下倾45°角喷洒指示剂丽春红-G溶液,收集并测定沉积在植株上层、中层和下层不同点位载玻片上的雾滴指示剂丽春红-G沉积量。【结果】以不同喷雾方式施药,水稻叶片正面、背面及垂直方向不同点位的丽春红-G沉积量有显著差异。在水稻分蘖期、孕穗期、扬花期用手动喷雾器叶面喷雾和弥雾机45°角下倾喷雾,丽春红-G的沉积量在水稻群体空间内的分布趋势均表现为上层>中层>下层。在水稻分蘖期用手动喷雾器叶面喷雾,13.3%玻片上丽春红-G的沉积量接近于平均数;52.9%玻片上丽春红-G沉积量低于平均数;33.75%玻片上丽春红-G的沉积量高于平均数。在水稻分蘖期用弥雾机45°角下倾喷雾,20.4%玻片上丽春红-G的沉积量接近于平均数;45.4%玻片上丽春红-G沉积量低于平均数;34.2%玻片上丽春红-G沉积量高于平均数。在水稻孕穗期和扬花期用手动喷雾器叶面喷雾,分别有33.3%和28.1%的玻片上没有丽春红-G的沉积;而用弥雾机45°角下倾喷雾,没有丽春红-G沉积的玻片比例分别为13.9%和5.0%。在水稻孕穗期用手动喷雾器和弥雾机喷雾,分别只有6.4%和11.7%玻片上的沉积量接近于平均值,而在扬花期时该比例分别为7.2%和17.2%。在水稻分蘖期、孕穗期和扬花期用手动喷雾器叶面喷雾,喷雾雾滴主要沉积在表示叶片正面的载玻片上,其沉积量占总沉积量的66.3%、85.1%和84.9%,其中在植株上层表示叶片正面载玻片上的沉积量占总沉积量的38.7%、42.2%和45.6%,在表示叶片背面和垂直面玻片上的沉积量很少。弥雾机下倾45°角喷雾,在表示叶片背面和垂直面玻片上的沉积量多于手动喷雾器叶面喷雾,但在表示叶片正面玻片上的沉积量仍占总沉积量的50.5%、50.6%和53.1%,其中植株上层表示叶片正面玻片上的沉积量占总沉积量的32.9%、27.9%和31.5%。【结论】如果以单位面积载玻片上的平均沉积量作为防治病虫害的有效剂量,那么在水稻群体内同时存在剂量浪费与剂量不足的现象。手动喷雾器压顶喷雾,喷雾雾滴主要沉积在植株上层叶片正面,沉积量占到总沉积量的1/3以上,而在叶片背面和茎秆上的沉积量很少,尤其是在植株基部叶片和茎秆上,沉积量趋向于零。采用弥雾机下倾45°角喷雾,喷雾雾滴在植株上层叶片正面的沉积量仍超过总沉积量的1/4,但在施药量低于手动喷雾器压顶喷雾条件下,各层叶片背面和茎秆上的沉积量都显著高于手动喷雾器叶面喷雾,说明弥雾机下倾45°喷洒,农药雾滴能够进入植株中下层,在叶片背面及茎秆上沉积。  相似文献   

17.
[目的]玉米抗倒伏化控剂喷施缺少适宜机具,拟通过开展植保机具选型试验,筛选适宜化控剂喷施作业的机型。[方法]采用大田试验与实验室检测相结合的方法,检测约翰迪尔4630型、3W-500型和3WBD-16型3种植保机型开展化控作业的适应性。[结果]4630型喷杆喷雾机配套防飘扇形雾喷头作业其雾滴粒径较大,雾滴沉积密度低,且多分布在下部叶片,不利于叶片吸收,化控效果较差,且植株损伤率最高;3WBD-16型背负式电动喷雾器配套圆锥雾喷头作业喷雾均匀性最低,化控作业后效果不均匀,田间整齐度低,作业成本最高;3W-500型东方红悬挂式喷杆喷雾机配套标准扇形雾喷头作业质量和作业效率优于背负式电动喷雾器,作业后化控效果显著优于约翰迪尔4630型喷杆喷雾机,且作业成本最低。[结论]3W-500型东方红悬挂式喷杆喷雾机适宜在京郊地区玉米化控作业中应用。  相似文献   

18.
A spray drift model called RTDrift was developed to estimate drift caused by ground sprayer machines. The sprayer was equipped with sensors measuring operational parameters namely spray pressure, boom height and movements, and geolocalisation. Climatic parameters, including wind speed and direction, were measured using a 2-D ultrasonic anemometer mounted on the sprayer. The nozzles spray drop size spectra were characterised using Phase Doppler Interferometer measurements. At every successive boom position, a diffusion-advection Gaussian tilted plume model computed the spray drift deposits for each drop class taking into account evaporation. The contribution of a single nozzle was calculated by integration of the individual puffs with respect to time and summation of the contributions of individual drops classes. The overall drift generated by the sprayer machine was obtained adding the contributions of all the nozzles. Field trials were performed on a fallow field with water and on crops with pesticides in various wind conditions. The ground drift was measured at different drift distances using fluorometric methods. When comparing the results of the model with experimental measurements of deposits, the model produced realistic maps of drift deposits. Some further improvement is needed in the presence of large scale eddies. The model offers potential benefits for the farmer as a real time drift estimator embedded on a sprayer machine.  相似文献   

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为了解植保无人飞机应用文丘里防飘喷头对水稻病害的防效影响。利用植保无人飞机搭载文丘里防飘喷头的方法,分析雾滴沉积特性及水稻纹枯病、稻曲病的防治效率。结果表明:应用文丘里防飘喷头雾滴在冠层上部与下部以及总体沉积量均超过应用常规扇形喷头的雾滴沉积量,相对于小雾滴,植保无人飞机采用大雾滴可以改善雾滴在冠层中的穿透性及喷幅范围内的雾滴分布均匀性;不论是粗雾滴还是细雾滴,植保无人飞机均可以有效防治稻曲病,而且防效优于传统的背负式喷雾器;纹枯病植保无人飞机应用文丘里防飘喷头施药后,其防效达到80%,与背负式喷雾器防效相当,较常规扇形喷头防效提高30%。因此,水稻叶部病害应用文丘里防飘喷头能够达到病害防治要求。  相似文献   

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