Accurate measurement of the downwash flow field of plant protection unmanned aerial vehicles (UAVs) is essential for analyzing the spatial distribution of droplets. To realize on-line rapid detection of the downwash flow field of a multi-rotor UAV, a flexible polypropylene detection device based on the principle of full bridge strain effect was proposed. Its performance principle was based on the physical deformation caused by wind pressure. The Fluid Flow and Static Structural modules of ANSYS 16.0 finite element software were used to simulate one-way fluid-solid coupling interaction. The surface of the resistive strain gauge embedded in the flexible detecting structure responded well to wind speed variation, hence it was suitable for downwash airflow wind field detection. By solving the strain force on the surface of the flexible detection structure, the length and layout of the grating wire of the strain gauge on the surface of the flexible detection structure were optimized. Meanwhile at 4 m·s-1 wind speed, the output voltage at varied bridge flexible acquisition systems in the acquisition card was measured. Results indicated coefficient of variation of 3.67%, 1.63% and 1.5%, respectively, which proved the good data acquisition consistency of the system. Through calibration test, the regression equation for the relationship between output voltage and wind speed for three unique sensor signal measuring circuits was established. The determination coefficients R2 for single bridge, half bridge and full bridge circuits were 0.9885, 0.9866 and 0.9959, respectively. In conclusion, by applying the multi-rotor plant protection UAV test platform, the results indicated the maximum relative error of the wind speed at each sampling point of the system at 1.0 m altitude was below 5.61%. Simulated and measured value had an RMSE maximum error of 0.1246 m·s-1. Moreover, downwash airflow detection not only has high accuracy but also has high sensitivity. Thus, there is convenience and practicability in the plant protection offered by this approach. The rapid measurement of UAV wind field and the established two-dimensional wind field model can provide a basis for precise application of agricultural aviation.

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Design of UAV Downwash Airflow Field Detection System Based on Strain Effect Principle

Uniform seed distribution within the row is the prime objective of precision planters for better crop growth and yield. Inclined plate planters are generally used for sowing bold seeds like maize, groundnut, chickpea, and their operating parameters like the forward speed of operation, the seed metering plate inclination, and the seed level in the hopper affect the cell fill and subsequently the uniform seed distribution. Therefore, to achieve precise seed distribution, these parameters need to be optimized. In the present study, out of the different optimization techniques, a new intelligent optimization technique based on the integrated ANN-PSO approach has been used to achieve the set goal. A 3–5-1 artificial neural network (ANN) model was developed for predicting the cell fill of inclined plate seed metering device, and the particle swarm optimization (PSO) algorithm was applied to obtain the optimum values of the operating parameters corresponding to 100% cell fill. The most appropriate optimal values of the forward speed of operation, the seed metering plate inclination, and the seed level in the hopper for achieving 100% cell fill were found to be 3 km/h, 50-degree, and 75% of total height, respectively. The proposed integrated ANN-PSO approach was capable of predicting the optimal values of operating parameters with a maximum deviation of 2% compared to the experimental results, thus confirmed the reliability of the proposed optimization technique.

Optimizing the seed-cell filling performance of an inclined plate seed metering device using integrated ANN-PSO approach

Research on the constitutive model of low-damage corn threshing based on DEM

A wedge-shaped no-tillage opener consisting of sharp front knife edge and pedestal with lateral wings has been designed. The front knife is connected with the pedestal by means of inner bolts and can be conveniently changed when it is abraded.Tests of resistance and power consumption are carried out in the field covered with maize straw.Test results show that the wedged-shaped no-tillage opener can reduce the surface soil disturbance to between 15% and 25%,and reduce the straw coverage rate by 10%～20%, so it can satisfy the requirement of no-tillage sowing.In comparison to the tine opener,it has the advantages that the soil bulk density is decreased significantly,the resistance and the fuel consumption are reduced by 13.2% and 15% separately when the depth of furrow opening is 10 cm,thus reducing the power consumption of tractor.So the wedged-shaped no-tillage opener solves the problem of high resistance and power consumption when the depth of furrow opening is 10 cm,and creates the loose seedbed,and which has important significance to the popularization and application of no-tillage seeders in China.

Design and Experiment on a Wedge Shaped No-tillage Opener

Полезная модель относится к сельскому хозяйству. Комбинированный почвообрабатывающий агрегат включает раму, на которой смонтированы вертикальные стойки с осями и установленные на осях с возможностью вращения сферические диски, имеющие регулируемый угол атаки, глубокорыхлители, сзади агрегата установлены транспортно-технологические колеса. По периферии каждого сферического диска выполнены выемки в виде полукруга, а режущая кромка сферических дисков заточена. С задней частью рамы агрегата закреплена катковая приставка, содержащая последовательно установленные катки рыхлительного и выравнивающего типа, Н-образную раму, кронштейны и штанги. На каждой штанге установлены гайки и пружина. Каток рыхлительного типа содержит ось и дисковые рыхлители, установленные на оси катка рыхлительного типа через равные интервалы в горизонтальной плоскости. По периферии дисковых рыхлителей выполнены треугольные выемки. Вершины, расположенные между треугольными выемками, также выполнены треугольными и двусторонне заточенными и направленными в разные стороны от геометрической оси вращения дисковых рыхлителей. Каток выравнивающего типа содержит ось, боковые и промежуточные диски, установленные на оси через равные интервалы в горизонтальной плоскости. По периферии боковых и промежуточных дисков выполнены треугольные выемки. В треугольных выемках боковых и промежуточных дисков и установлены рыхлители таким образом, что они образуют винтовую линию. Направление винтовой линии выравнивающего катка начинается от его продольной оси симметрии и направлено в сторону боковых дисков. Рыхлители в поперечном сечении выполнены квадратными и скрученными по всей длине на угол α относительно своей продольной оси симметрии таким образом, что острые кромки каждого рыхлителя образуют винтовые линии. Острые грани рыхлителей направлены в разные стороны от геометрической оси вращения выравнивающего катка. Обеспечивается повышение качества обработки почвы. 4 ил.

Комбинированный почвообрабатывающий агрегат

In order to improve the pesticide application efficiency and reduce the agricultural chemicals lost in fruit trees spraying, an automatic target spraying system of canopy scanning identification based on the sprayer is designed in view of excess spraying and ineffective spray at trees gaps during traditional spray operation. The ultrasonic sensors are installed on the boom of the sprayer under profile modeling spray to detect the crop canopy. Based on the sensor signals, solenoid valves by side are used to control the switch of nozzles at the corresponding position. The experiment of target spray system is worked at the six year-old landscape tree. The results show that the target spray system can effectively save the amount of application pesticides compared with continuous spray. The target spray system can save pesticides 47.8% at the travel speed of 1 m/s for the gap rate 46.7% of landscape tree. Thus, the target spray system of the sprayer has good application value to the pest control of sparse fruit trees and other crops.

Ultrasonic Sensing System Design and Accurate Target Identification for Targeted Spraying

The utility model relates to a garlic harvester with a residual film recovery function. Power device, wherein the cutting device and the excavating device are installed on the power device. The powerdevice is further provided with a plastic film residue collecting device, and the plastic film residue collecting device comprises a supporting frame located in front of the cutting device, a windingframe connected to the supporting frame through a shaft and a first driving device which drives the winding frame to rotate and is installed on the supporting frame. According to the utility model, the functions of seedling cutting, seedling throwing, digging, soil shaking transportation, residual film collection and the like can be efficiently completed; the tasks of feeding, cutting and throwingaway garlic seedlings can be effectively completed, the efficiency is high, and the miss-cutting rate is low; the residual film collecting device can effectively pull the residual film out of the field and orderly wind the residual film on the residual film winding rod; residual mulching films which are not completely harvested can be recycled through the residual film recycling device, the fieldresidual quantity of the mulching films is reduced, the impurity rate of harvested garlic is reduced, and the quality of the harvested garlic is improved.

Garlic harvester with residual film recovery function

The developed high-branch pruning machine is a novel type of high-altitude operation machine which can realize tall tree pruning work Operators can adjust manipulator posture and cutting position through friendly Human-Machine-Interface (HMI) to control pruning saw realizing pruning operation Based on the previous research, dynamic balance problem of the machine caused by the posture adjustment of the manipulator is considered in this paper Firstly, working principle of the high-branch pruning machine, manipulator mechanical structure and basic dynamic balance principle are elaborated Secondly, the correspondences between manipulator posture and tilting torque, tilting torque and counterweight displacement, are studied based on kinematics analysis and mechanical structure analysis Thirdly, Consider the numerical calculation and analysis results, the structure of the dynamic balance system and control method are designed Finally, it is verified by the prototype pruning test in the open area The test results show that the pruning machine can achieve dynamic balance under the given control algorithm

Dynamic Balance System Design and Control for High-Branch Pruning Machine

The invention relates to a self-propelled Chinese cabbage harvester having variety adaptability. The self-propelled Chinese cabbage harvester comprises a crossbeam frame, a hydraulic device, a guiding device, a cutting device, an inclined conveying device and a horizontal conveying device. A bearing crossbeam is a bearing frame and used for supporting and fixing other devices. A clamping device is used for clamping and fixing Chinese cabbages and preventing position deviation of the Chinese cabbages. The cutting device is used for cutting the roots of the Chinese cabbages. The guiding device is used for overall guiding and leaf vegetable drawing. The inclined conveying device is used for conveying the Chinese cabbages of which the roots are cut. The horizontal conveying device is used for conveying the harvested Chinese cabbages to a basket. Complete mechanical work of the processes of clamping, cutting, conveying and casing of the Chinese cabbages can be realized, harvesting work of different varieties and sizes of Chinese cabbages can be performed, and the breakage rate of the Chinese cabbages in the harvesting process can be greatly reduced and the labor productivity can be enhanced.

Self-propelled Chinese cabbage harvester having variety adaptability and method thereof

The invention relates to an automatic guiding and positioning device for a greenhouse plant protecting robot and a control method. The automatic guiding and positioning device comprises a frame, a walking guiding device, a positioning device and a control system; the frame is used for supporting and fixing other devices; the walking guiding device is fixed on the frame and used for driving and guiding the frame; the positioning device is used for positioning the plant protection robot during the walking process and correcting the walking direction of the plant protection robot; a drug applyingdevice is used for spraying pesticide to vegetable crops in the greenhouse; the control system is used for controlling the greenhouse plant protecting robot to complete the walking, positioning, drugspraying and other actions. The device and control method apply the automatic guiding and positioning; the walking direction of the greenhouse plant protecting robot is automatically revised throughthe machine vision, thus the track is omitted; the other works of the greenhouse are not influenced when the spraying work is not carried out; the front wheel is universal, and the back wheel is driven at differential speed; the device can independently walked and guided, and the greenhouse changing work is realized.

Niu Ziru

Papers

Ultrasonic Sensing System Design and Accurate Target Identification for Targeted Spraying

Garlic harvester with residual film recovery function

Dynamic Balance System Design and Control for High-Branch Pruning Machine

Self-propelled Chinese cabbage harvester having variety adaptability and method thereof

Automatic guiding and positioning device for greenhouse plant protecting robot and control method