Spray Boom Research Articles

A means of destroying sites of perennial root shoot weeds with pests and diseases in them

BACKGROUND: The subject of the study is the technological process of protective spraying of agricultural crops using a combined method against perennial weeds in sites in the field using two pneumohydraulic devices with slot atomizers as part of an improved small-sized boom sprayer. AIM: Development of a technical mean for exterminating sites of perennial root shoot weeds with pests and diseases in them. METHODS: The developed pneumohydraulic devices were used for an improved mounted boom sprayer of plants to treat sites of perennial weeds in the field. Chemical spraying with combined use of the traditional method and the developed pneumohydraulic devices with axial fans and 12 V electric motors, ensuring the distribution of droplet liquid on the treatment surface with two sprayers over 4 meters, is able to reduce the amount of the applied chemicals compared to the conventional technology and to reduce the pesticide load on crop plants by local destruction of sites of weeds, pests and diseases. Based on the developed methods, the results of spraying the surface with a drop liquid with a known dispersion using slot sprayers and controlled liquid pressures with a dial gauge during experiments were obtained. SCIENTIFIC NOVELTY: For the first time, a combined method and technical mean of achieving the research aim have been proposed for the destruction of sites of perennial weeds in the field and the diseases and pests of agricultural crops spread in them. RESULTS: When using a mounted sprayer with two containers for working fluids of combined herbicide solutions or for an insecticide solution in one of the containers and installation of the improved pneumohydraulic devices on the edges of the boom with a conventional arrangement of slot atomizers, it is possible to meet agrotechnical requirements for the use of herbicides, insecticides and fungicides. The simultaneous impact of large drops of herbicides on weeds and the penetration of small drops into plants will destroy sites of rhizome and root weeds with pests and diseases to ensure favorable conditions for the production of agricultural crops. CONCLUSION: A combined method and the technical mean of chemical treatment of perennial weeds with pests and diseases to create favorable conditions for the production of cultivated plants has been experimentally substantiated. Compliance with the conditions is ensured by equipping the mounted sprayer with two containers, pumps for supplying liquid through hoses to slot atomizers, and installing pneumohydraulic liquid nozzles at the edges of the boom. Working liquid sprayers ensure spraying width of more than 4 m, taking into account the size of a site, as well as spraying inaccessible areas using conventional technical means. The efficiency of the developed combined protective spraying of agricultural crops against perennial weeds and pests by the technical mean of its implementation lies in the savings of expensive herbicides and insecticides up to 70% in the later stages of their growing season (as they grow over the field area) compared to the forced continuous application of the herbicide over the entire field area.

A method to spatially assess multipass spray deposition patterns via UV fluorescence and weed population shifts

AbstractSpray deposition patterns from agricultural sprayers are traditionally sampled discretely along a field transect accounting for 0.5% or less of the treated area. Such methods may not fully capture the dimensional variability inherent in large‐scale, multiple‐pass spray applications, especially evident from an agricultural spray drone (ASD). This study investigated the utilization of UV‐fluorescent dye and nighttime aerial imaging techniques to assess large‐scale, multipass spray deposition patterns. Accuracy of digital hue from UV‐fluorescent photography to predict deposition of proxy dye was confirmed via fluorometry assessed intensity levels of extracted UV‐fluorescent dye from 384 Petri dishes placed prior to treatment. Results showed that ASD applications, regardless of nozzle type, exhibited greater spatial variability within the target area compared to ride‐on sprayer applications, primarily due to overapplication. Additionally, the ASD generated spray drift to adjacent nontarget areas that was at least three times more than that of ride‐on and spray‐gun sprayers. Multipass deposition was further assessed via in situ smooth crabgrass infestation following treatment with quinclorac or topramezone by multipass ASD or hand‐held, four‐nozzle spray boom. Weed infestation annotated from overlaid grids with 9.3‐dm2 ground resolution inconsistently detected spatial heterogeneity between transects assessed along the center and edge of each sprayer pass. The ASD controlled smooth crabgrass 11% more than the hand‐held sprayer, albeit with an 18% increase in spray drift to nontarget areas, similar to the UV‐fluorescence study. Digitally assessed average hue of fluorescence photography appears to be a viable method to assess multidimensional and continuous spatial relationships of spray deposition.

Horizontal Distribution of Liquid in an Over-Row Sprayer with a Secondary Air Blower

The aim of this study was to determine the influence of boom height above a crop stand and the spacing between nozzles and diffusers in an over-row sprayer on the uniformity of the horizontal spray distribution and the uniformity of the air velocity distribution. The experimental setup involved a prototype over-row sprayer equipped with a boom with a working width of 8 m and ten air diffusers with spray nozzles. Air diffusers were connected to one or two nozzles each, and they were installed on the boom at intervals of 60, 80, and 90 cm. Terminal airflow velocity at a canopy is determined by the height of a sprayer boom and the diffuser spacing, ranging from around 2 m s–1 to around 27 m s–1. The sprayer boom should be positioned at a height of 50 cm above a crop stand due to the difference between the minimum and maximum airflow velocities. The horizontal spray distribution was more uniform when the sprayer was equipped with hollow-cone nozzles instead of flat-fan nozzles; hollow-cone nozzles should be applied if the distance between nozzles needs to be adjusted to the row width and row spacing. The analyzed coefficients did not exceed 10% when the boom was positioned 50 cm above the crop stand and when the nozzles were spaced 80 cm apart, which suggests that, in this configuration, sprayers equipped with hollow-cone nozzles can also be applied to close-grown crops.

Development of a flexible electronic control unit for seamless integration of machine vision to CAN-enabled boom sprayers for spot application technology

This research work aimed to develop an Electronic Control Unit (ECU) to establish a flexible bridge between machine vision and boom sprayer to control nozzles individually for pesticide spot application based on the Controller Area Network (CAN). The ECU consisted of two electronic entities. The first used UART protocol to parse machine vision messages, detect pest areas, and convert them into binary arrays for nozzle activation. The second received these arrays and generated nozzle controller CAN frames which were broadcast to control the sprayer nozzles on the implement bus. The ECU was tested in four scenarios involving combinations of three machine vision systems and two nozzle systems. The lab tests confirmed, assuming accurate detections, the ECU successfully sent spray commands to all targets across various camera-nozzle ratios. However, at specific ratios (1:3 and 1:6), some nozzles opened in unintended patterns. In the fourth scenario conducted in the field at a 1:2 ratio, all targets were sprayed regardless of their dimensions and distribution in the field. In this scenario, the sprayer operated at speeds of 3.22 km/h, 6.44 km/h, and 9.66 km/h, demonstrating real-time spraying with 55° angled nozzles, where the ECU sent CAN messages every 10ms and issued 400 ms spray commands upon detection, achieving a minimum spray length of 345 mm per detection.

Optimization of a Boom Height Ultrasonic Detecting Model for the Whole Growth Cycle of Wheat: Affected by the Oscillation of the Three-Section Boom of the Sprayer

In the dynamic operation of a boom sprayer, the boom oscillation will cause the detection value of the boom height to fluctuate greatly, resulting in failures of the control system. Based on the previously developed static boom height detection model for the entire wheat growth cycle, this study aimed to optimize the model to reduce the impact of boom oscillation on the accuracy of boom height detection. Three ultrasonic sensors were installed on each section boom of a three-section boom sprayer, and dynamic boom height detection tests were conducted at vehicle speeds of 4 to 8 km/h across six growth stages of winter wheat in Beijing, a total detection area within a single fixed operational row of approximately 14 ha. The test results showed that as vehicle speed increased, boom oscillations intensified across all sections. By setting the boom oscillation correction parameters, the detecting value of each section of boom height is corrected. The results show that the fluctuation and deviation degree of the boom height-detecting value are obviously reduced, and the correction effect is obvious. Further analysis of the detecting value of the boom height after the correction shows that the previously established detection model still maintains high detection accuracy under dynamic conditions; that is, the detection position of the ultrasonic sensor does not downward shift. This paper provides a low-cost technical method that can be directly applied to the dynamic detection of boom height.

Modal test and finite element updating of sprayer boom truss

In addressing the finite element model and actual structural error of the sprayer boom truss, this study aims to achieve high-precision dynamic characteristics, enhance simulation credibility, make informed optimization decisions, and reduce testing costs. The research investigates the dynamic behavior of the sprayer boom truss through modal experiments and finite element simulations. Initially, modal parameters of the sprayer boom are obtained through experimental testing, validating their reasonableness and reliability. Subsequently, Ansys Workbench18.0 simulation software was employed to analyze the finite element model of the sprayer boom, revealing a maximum relative error of 11.93% compared to experimental results. To improve accuracy, a kriging-based response surface model was constructed, and multi-objective parameter adjustments using the MOGA algorithm reduce the maximum relative error to 4.6%. Sensitivity analysis further refines the model by optimizing target parameters, resulting in a maximum relative error of 4.96%. These findings demonstrate the effective enhancement of the corrected finite element model’s precision, with the response surface method outperforming sensitivity analysis the maximum relative error between the updated finite element model and experimental results was within the engineering allowable range, confirming the effectiveness of the updated model.

Empowering Vegetable Farmers: Energy Analysis and Evaluating the Impact of a Battery-operated Boom Sprayer

Empowering Vegetable Farmers: Energy Analysis and Evaluating the Impact of a Battery-operated Boom Sprayer

Analysis of test results of the P-20 multi-rotor UAV when spraying pesticides in precision agriculture

Abstract The article provides an overview of the current results of using multi-rotor UAVs when spraying pesticides in precision agriculture. It is noted that, as part of improving the technology for using UAVs, it is necessary to continue work on optimizing and testing the parameters of UAV transport and technological cycles together with a reasonable choice of special reagents and their combinations to improve the spraying effect and increase the level of use of pesticides. This will directly affect the improvement of the quality and efficiency of precision farming systems. The analysis presented in the work is based on testing the parameters of the transport and technological cycle of a multi-rotor UAV of the P-20 type, which was used to spray pesticides on cotton fields to combat aphids and spider mites on cotton at the flowering and boll setting stages. The results are considered that make it possible to analyze and compare the laws of uniform and penetrating deposition and drift of droplets in cotton canopies at different UAV flight altitudes. It has been shown that spraying small volumes of agrochemicals using UAVs at low altitudes differs from operations performed using modern manned aircraft or boom sprayers. The flight altitude of the UAV has a significant impact on the deposition and drift of droplets. The results of studies related to elucidating the effect of defoliant adsorption on cotton leaves are also noted. The adsorption of acetamiprid and spirodiclofen was studied. Methods for statistical processing of the obtained experimental data are presented, in particular, to test the significance of the influence of flight altitude on the experimental results.

Design and systematic evaluation of an under-canopy robotic spray system for row crops

Despite having made much improvement in sensing, automation, and control, the current broadcast spraying system has several drawbacks, such as uneven coverage, excessive chemical use, and deviation from recommended dosage. Typically, farmers use large self-propelled sprayers to spray the entire field without knowledge of spatial pest severity, potentially resulting in an unintentional application. However, application errors and the extent of chemical use can be optimized by utilizing an intelligent site-specific decision-based sprayer to control pests more efficiently. Hence, the initial project goal was to design a robotic liquid application system for row crops (e.g., sorghum and corn) and validate sprayer system performance. The critical design considerations for the spray application system were modularity; the ability to be mounted on an autonomous platform to go within 76.2-cm spaced crops; spray on either side of the crop row using spray booms; onboard hardware and software for control and data acquisition; and record as-applied data. A system with desired design requirements was built and individual sub-systems were tested under simulated lab scenarios to quantify the response time and accuracy of the spray system. The results showed that the sprayer could maintain an average system pressure within ±5% of the target under different duty cycles for each of the six nozzles. At 40% duty cycle, the nozzle pressure settling time at an error margin of ±5% from the mean was 13 ms, 20 ms, and 19 ms, for one, three, and six nozzles, respectively. Also, no substantial pressure difference was observed between nozzles installed at different heights in two different booms. Therefore, this application system could be a viable solution for autonomous platforms to site-specifically apply pesticides only on critically infested plants, has the potential to decrease the overall input costs on chemicals and reduce the negative environmental impacts.

Design of inductive electrostatic boom spray system based on embedded closed electrode structure and droplet distribution test in soybean field.

The large water demand, insufficient deposition on the back of the leaf and the uneven distribution of droplets are the problems of traditional agricultural ground plant protection machinery, which leads to low agricultural control efficiency. Combined with the advantages of electrostatic spray technology and the characteristics of high working efficiency and low probability of droplets drift of ground sprayer, an inductive electrostatic boom spray system based on embedded electrode structure is designed and mounted on a large self-propelled boom sprayer for field testing. Based on the working characteristics of the fan nozzle and the analysis of the theory of charge, the inductive electrostatic spray device is designed. The performance of the device is tested and the rationality of the system design is verified by COMSOL numerical simulations, charge-to-mass ratio, and particle size distribution measurements. The spray deposition scanning software and the Box-Behnken experimental design method are used to analyze the spray droplet deposition rate and coverage density of the sprayer on the front and back of the target leaves. The results show that the embedded closed electrode structure designed in this paper can avoid the problem of electrode wetting, and the electric field generated by it is mainly concentrated in the spray liquid film area, and the intensity reaches 6~7 V/m. At the conventional application height (500 mm), the maximum charge-to-mass ratio is 2.91 mC/kg, and the average particle size is 168.22 μm, which is 12.87% lower than that of ordinary spray, when the spray pressure is 0.3 MPa and the electrostatic voltage is 12 kV. The results of field experiments show that the optimum combination of the working parameters with the spray speed is 8.40 m/s, the spray pressure is 0.35 MPa, the charging voltage is 11.50 kV, the amount of droplet deposition in the lower dorsal area of the blade is 1.44 µL·cm-2. This study can provide a certain basis for the application of electrostatic spray technology in ground sprayers.

Effects of Magnetized, Chelated Iron Foliage Treatments, and Metal Halide Lamps on Plant Water Structure, Water Vapor Dynamics, and Resilience for Legumes under Water Stress

A greenhouse study was conducted to determine the effects of foliar applications of magnetized, chelated liquid iron fertilizer for increasing the drought tolerance of two legumes. The study objectives were to determine the drought tolerance effects of four treatments on foliar gas exchange, soil moisture, and plant growth for soybean (Glycine max) and velvet bean (Mucuna pruriens) plants. The plant treatments included applications with chelated liquid iron fertilizer (2.5 and 5%) with a conventional boom sprayer, with and without magnets in the spray lines, and metal halide lamps. Three gas exchange measurements were collected before applying the foliage treatments and after two water stress treatments. A foliage and metal halide lamp treatment deactivated or unlinked nine interconnected gas exchange parameters that are correlated with plant defense activities during water stress conditions. The deactivation of interconnected regulatory gas exchange functions improved metabolic efficiency, reduced stress levels, and boosted plant resilience to abiotic stressors. Also, the study findings suggest that the study treatments maintained or increased the level of biologically structured water in plant tissues and vascular systems.

喷杆倾角控制系统的设计与实验

During field operations of the spray boom sprayer, the distance between the ends of the spray boom and the height of the crop canopy affects the uniformity of spraying, requiring operators to manually adjust the spray boom to be parallel to the crop canopy, which impacts operational efficiency. This study presents the design of a boom tilt control system, consisting of a main control node, distance measurement node, vehicle tilt detection node, and spray boom tilt control node. The bus communication protocol for the spray boom tilt control system is defined according to the ISO11783 standard, and a serial communication network is designed, along with the development of a real-time dynamic monitoring interface for the spray boom. The system automatically monitors the height of the boom and the tilt of the vehicle, makes decisions based on the detection information, controls the electric actuator, and adjusts the tilt of the boom. Leveraging the advantages of fast computing speed and user-friendly human-machine interface of the PC, as well as the high cost-effectiveness and small size of the microcontroller, and the multi-master-slave structure of the CAN bus, this system can complete data acquisition, processing, and other functions required for spray boom tilt control, achieving automatic adjustment of spray boom tilt. This enhances spray uniformity and operational efficiency of the sprayer, while reducing the workload of operators.

摆式主被动悬架喷雾机喷杆稳定性试验研究

When a sprayer is operating in the field, the uneven ground excitation causes the spray boom to move irregularly, significantly affecting the spray distribution uniformity and reducing the effectiveness of pesticide application. Installing a suspension between the vehicle and the boom is a crucial method to improve the boom stability. In this paper, experimental research on the stability of a boom with an active and passive pendulum suspension was carried out. The results of the transient response test of the passive suspension demonstrate that an increase in the suspension rotation damping coefficient reduces the overshoot of the system but slows down the response speed. Conversely, an increase in the suspension rotation stiffness coefficient speeds up the response speed. The results of the dynamic response test of the active suspension indicate that a smaller adjustment threshold of the control system for the boom inclination angle results in higher control accuracy. However, when the threshold is less than 1cm, the boom becomes challenging to balance. The results of the combination experiments based on the response surface method reveal that the rotation stiffness coefficient, rotation damping coefficient, unit forward speed, and their interactions significantly impact the adjustment time of the boom and the variation coefficient of the boom inclination angle. Through contribution rate analysis, the influence order of each factor on the adjustment time and variation coefficient was obtained. Additionally, the analysis of variance results show that the established regression model fits the actual situation well, and has reference significance for the design and application of the suspension.

Optimization of Parameters of Adaptive Spray System for Agricultural Sprayer

Introduction. When growing tall-growth crops (cereal crops in late the phases of development, corn, sunflower, etc.), there are used boom sprayers equipped with twin-fluid spray cones with fixed angles of inclination to the vertical of the spray cones. The working fluid is applied with such sprays are more intensively on the front side of the plant leaves while the intensity of covering the plants from the back side with the working fluid decreases. The development of the spray system will allow improving the quality of crop treatment with boom sprayers. Aim of the Study. The aim of the research is to determine experimentally the algorithm for changing the angles of inclination of a twin-fluid spray cone that provides the same intensity of applying working liquid to the leaves of high-growth plants. Materials and Methods. The research was carried out on a test bench by applying colored water to the front and rear sides of a tall-growth plant model moving at a specified speed. The experiment was carried out according to the method of optimal planning. The difference between the content of droplets on the front and rear sides of the tall-growth plant model was taken as an optimization parameter. Variable factors were the spray cone inclination angles and the operating speed of the sprayer. Results. The algorithm for changing the optimum values of the spray cone inclination angles depending on the sprayer speed was determined based on the equality of the first derivative of the optimization to zero parameter by the value of these angles. Discussion and Conclusion. According to the algorithm, when the sprayer operating speed increases from 1.2 to 3.2 m/s, the optimal angle of inclination to the front spray cone vertical changes linearly from 25 to 21 degrees, and the rear one ‒ from 46.7 to 57 degrees. This algorithm will allow justifying the technical specifications to develop a processor for automatic control of the spray cone inclination angles cones when the sprayer is operating.

GNSS Guidance in Mulching-based Cultivation of Black Soybean ‘Tanbaguro’ and Partial Application of Herbicide to Furrows Using a Boom Sprayer

GNSS Guidance in Mulching-based Cultivation of Black Soybean ‘Tanbaguro’ and Partial Application of Herbicide to Furrows Using a Boom Sprayer

Justification of range limits of root spray angle of an adaptive spraying device

BACKGROUND: Oscillations of the sprayer field boom in the transverse-vertical plane causes a decrease in the quality of the technological operation. This is especially true in relation to the operation of small-sized single-support barrow-type sprayers. One of the possible solutions to compensate the effect of transverse oscillations of the boom on the quality of spraying is the use of adaptive sprayers with a variable root angle of the spray jet, responding to the position taken by the sprayer in relation to the surface being treated. AIM: Justification of the necessary limits for changing the spray angles of an adaptive sprayer for a single-support spraying device. The novelty of the research lies in the fact that insufficient attention is paid to the implementation of technologies using means of small-scale mechanization, unlike industrial agricultural machinery. METHODS: A prototype of a single-support boom motor sprayer was used as the study object. The field experiment was carried out at the experimental area of the Oryol State Agrarian University. Data acquisition on the deviation of the sprayer from the vertical axis was carried out using a specially developed angle gauge. A spreadsheet processor in the Microsoft Excel environment was used to perform mathematical processing of the decrypted experimental data. The study of the obtained analytical dependencies was carried out in the environment of the Mathcad 14.0 mathematical calculation system. RESULTS: It has been experimentally found that the maximum deviations of the sprayer from the vertical can be up to 30° during operation. At the same time, the average amplitude of the transverse operating oscillations of the boom of a single-support barrow-type boom sprayer ranges from +11° to -18°. The amplitude of the transverse oscillations of a single-support sprayer depends on the operator’s skills and the unit motion velocity. Balancing the sprayer is important due to the moment of force caused by the weight of the one-sided field boom. A formula for calculation of the spray width of one sprayer, taking into account the geometric parameters of a single-support sprayer, as well as its inclination angle in the transverse-vertical plane, has been derived. An analytical relationship that makes it possible to calculate the required limits of the root angle of the spray jet of an adaptive sprayer, taking into account the installation distance of the sprayer relative to the vertical plane passing through the support point of the sprayer, has been obtained. The values of the root spray angles for the deflectors of adaptive sprayers, with the sprayer oscillations amplitude from -18° to +11° in the transverse-vertical plane, were found. CONCLUSIONS: The practical value of the study lies in the potential of using the formula to determine the range limits of root spray angles when designing and developing adaptive sprayers.

Optimal Design and Dynamic Characteristic Analysis of Double-Link Trapezoidal Suspension for 3WPYZ High Gap Self-Propelled Sprayer

A fast spraying speed, wide working area, and easy operation are the operational advantages of high-clearance boom sprayers. To address the issue of spray boom mechanical vibration affecting the spraying effect, a double-link trapezoidal boom suspension is designed for the 3WPYZ sprayer. This suspension can achieve passive vibration reduction, active balance, and ground profiling. The kinematic model of the boom suspension is established based on D’Alembert’s principle and the principle of multi-body dynamics, and the design factors affecting the stability of the boom are determined. Through orthogonal experimental design and virtual kinematics simulation, the influence of the boom length and orifice diameter of each part on the swing angle and the natural frequency of the boom suspension is investigated. Design-Expert 8.0.6 software is used to analyze and optimize the test results. The optimization results show that, when the connecting boom length LAB is 265 mm, the inner boom suspension boom length LAD is 840 mm, the outer boom suspension boom length LBC is 1250 mm, and the throttle hole diameter d is 4 mm; the maximum swing angle of the boom suspension is reduced by 53.02%. In addition, the natural frequency of the boom is reduced from 1.3143 rad/s to 1.1826 rad/s, and the dynamic characteristic optimization effect is remarkable. The modal analysis results show that the first sixth-order vibration test frequency of the boom sprayer suspension designed in this paper meets the requirements and avoids the influence of external factors. Field tests show that, when the sprayer is excited by the environment at 3.5° to 4°, the boom suspension can reduce the vibration transmitted by the body to a reasonable range. The static analysis shows that the structural design of this study reduces the stress at the connection of the end boom suspension, the maximum displacement, and the maximum stress of the inner boom suspension. The test results of the dynamic characteristics of the implement are basically consistent with the virtual model simulation test results, thus achieving the optimization objectives.

Vibration loading of self-propelled sprayer booms on ultra-low pressure tires

BACKGROUND: The article presents the results of experimental studies of the vibration loading of the booms of a self-propelled sprayer equipped with ultra-low pressure tires 1020x420-18 model Bel-79 when driving through single artificial bumps. Based on the results of the tests, the dependences of the influence of maximum vertical accelerations on the suspension of rods on the speed of movement at different air pressure in the tires and levels of filling the sprayer tank with process liquid were obtained. It has been established that with a decrease in the filling of the tank with process liquid and an increase in the speed of movement, the level of fluctuations on the sprayer booms proportionally increases relative to the full filling. When moving a self-propelled sprayer through artificial irregularities with the booms opened in the working position, located at a distance of 700 mm from the supporting surface, in the entire range of speeds from 3 m/s to 12 m/s, the oscillation amplitude at the ends of the booms did not exceed 80 mm.
 AIMS experimental evaluation of the impact of operational parameters of a mobile power tool equipped with ultra-low pressure tires on the vibration loading of sprayer booms.
 METHODS: Methods of laboratory and field research on the passage of a mobile power tool equipped with a boom sprayer through artificial bumps are given. The maximum vertical accelerations on the sprayer booms were determined using the ASSISTANT TOTAL instrument complex, which consists of a measuring unit with a vibration analyzer and an AR38R vibration transducer.
 RESULTS: The dependences of the influence of air pressure in ultra-low pressure tires and the speed of movement of the MEV-600 on the level of fluctuations of the sprayer booms when moving along artificial single irregularities are obtained. The minimum level of fluctuations on the rods at different air pressures in tires and different degrees of tank filling reaches at a MES speed of 9 m/s. The most vibration-loaded for sprayer booms is the empty driving mode.
 CONCLUSIONS: 
 The minimum level of fluctuations on the sprayer booms takes place in the speed range of 7.5 - 10.5 m/s. When the air pressure in the tires is reduced from 80 kPa to 20 kPa, the vibration loading of the rods is reduced by 2.8 times. An increase in vibration loading takes place in the range of filling level of the sprayer tank from 50% to empty. When moving along individual irregularities in the speed range from 3 m/s to 12 m/s, the sprayer booms were stably in a horizontal position, no intense vibrations and resonant modes of boom sections were observed.

Air assistance and spray volumes on the coverage, droplet density, and spray deposition in melon plants

This study aimed to evaluate the influence of air assistance on the coverage, droplet density, and deposition of the mixture volume applied to melon plants. The experiment was conducted in a completely randomized design set up in a 4 x 4 x 2 factorial arrangement referring to four spray nozzles (AVI 110-02, TT 110-02, AVI 110-03, and TT 110-03), four mixture volumes (140, 200, 300, and 400 L ha-1), and two application techniques (with and without air assistance), at a constant working pressure of 300 kPa. Deposition analysis was performed by using a bright blue dye, and the coverage pattern and droplet density were analyzed using water-sensitive paper tags attached to the adaxial and abaxial surfaces of the leaf blade of melon plants. Air assistance in the spray boom improved the deposition of the mixture sprayed on melon leaves only when using nozzle TT 110-02, whereas nozzles TT 110-03, AVI 110-02, and AVI 110-03 were not influenced by air assistance. Coverage and spray deposition on the adaxial leaf surface increased with the mixture volume applied for all nozzles. The technique using water-sensitive tags is not efficient to evaluate droplet density when working with high spray volumes.

Концепция применения адаптивной штанговой распределительной системы малогабаритного одноопорного опрыскивателя

A small-size sprayer with vertical oscillations of the distributor boom without complex copying and compensating devices does not provide quality spraying. Primary seed production requires the development of new approaches to ensure the spreading accuracy of plant protection products (PPP). For this purpose the concept of application of adaptive distribution system of a small-size boom sprayer is proposed and theoretically substantiated. Field experiments with the use of a single-axis boom sprayer of the wheelbarrow type were carried out. The theoretical description of conditions of fulfillment of the spraying operation in relation to violation of the scheme of distribution of working liquid is given. Optimization of values of current frontal angles of the spraying torch is carried out. It has been established that the average range of vertical vibrations of the boom of a single-legged sprayer, like a wheelbarrow, ranges from 16° to 29°. A hypothesis has been proposed to increase the uniformity of distribution of liquid preparations. This is achieved by controlling the geometry of the spray pattern. Analytical dependences of the influence of the geometric parameters of the sprayer and the angle of its transverse inclination on the formed width of the processed strip and the required spray pattern angle were found. A nomogram and operational schedule of sprayer operating modes for the adaptive sprayer distribution system have been developed. With a base spray angle of 110°, the permissible limits for the width of the processing strip; with a lower tilt of the boom, a spray angle of 85° is provided, and with an upper tilt, 135 to 145°. The use of the original balancing device reduces the vertical boom oscillation range up to 14°. The difference in the values of the coefficient of variation of the transverse distribution of the working fluid, at typical and adaptive orientation of the planes of the spray-cone angle in the model experiment was 9.5%. The proposed hypothesis is confirmed.