Design And Experimental Research Of Rail Multi-row Sprayer In Greenhouse

At present,the existing conventional greenhouse plant protection sprayers include hand-push sprayers,hanging sprayers,orbital sprayers,and self-propelled sprayers.the hanging vine greenhouse plant protection machine is not yet mature in China.while the artificial greenhouse for hanging vine greenhouses is mainly for artificial application.This paper’s purpose is to design a greenhouse rail multi-row sprayer.Under the three operating speeds and the presence or absence of laying rails,the sprayer is studied about the maximum angle of the greenhouse topography to the swing of the multi-row operating mechanism of the sprayer and the direction of vertical direcyion of the suspension mechanism.The installation angle of the hanging rail contraction mechanism is corrected by the theoretical value and the experimental value.The test selects the best combination of top and side spray and the optimal sprayer operating conditions at 2 speeds and 2 spray pressures.The research content of this paper mainly includes the following five aspects:(1)Structural design of orbital multi-row sprayerThe laying method of the track,the moving device,the multi-row spray mechanism for avoiding obstacles,the spray system used in the test and the track type multi-row sprayer were developed.The running speed is 0.4~1m/s.The obstacle avoidance multi-row spray mechanism can realize the adjustment height of 1.6~2.2 m,which can meet the spray method of different height crops.(2)Theoretical study on the swinging of the crossbar of the rotating mechanism of the sprayer and the deflection mechanism of the hanging railAccording to the crop line spacing calculation,the maximum deflection angle of the hanging rail is 5.7°.According to the strength requirement,a square aluminum material(6063-T5)with a cross-bar length of 1.25 m and a cross-sectional area of 30 mm~2 is selected.The maximum deflection of the crossbar end is 4.99 mm and the rotation angle of the free end is 5.2°.The analysis results of Ansys Workbench show that the strength of the crossbar meets the design’s requirements.By designing the angle between the suspension rail and the crossbar to be 84.8°,the deflection angle of the suspension rail is eliminated,so that the suspension rail is in a vertical position when the sprayer is at rest.The greenhouse topography was measured to obtain the greenhouse topographic spectrum,and a two-degree-of-freedom vibration system model of the sprayer was established.The maximum deflection angle generated by the suspension rail of the model at three speeds was analyzed,which meets the design requirements within the maximum deflection angle obtained by theoretical analysis.(3)Study on the amplitude of the swing of the sprayer’s crossbar caused by uneven groundThrough the test sprayer,under the conditions of three kinds of moving speeds and the presence or absence of laying rails,the free end swing amplitude and the hanging rail deflection angle caused by the uneven excitation pump of the terrain were studied.The relationship between ground irregularities and the amplitude of the sprayer’s crossbar swing indicate that the free end acceleration of the crossbar is a_X>a _Z>a_Y,and the amplitude of the swing increases with the increase of the speed without the laying of the rail,and the vertical motion is downward.The amplitude of the swing is greater than the amplitude of the upward swing.The acceleration of the hanging rail a_Y>a_X>a_Z is mainly in the lateral movement.The amplitude of the deflection increases with the increase of the speed,and the amplitude of the lateral movement of the sprayer’s hanging rail to the inner side is greater than the amplitude of the outward swing.(4)Deflection angle test of the contraction mechanism of the sprayer’s hanging rail caused by uneven groundThe sprayer is subjected to the unevenness of the greenhouse topography,and the maximum deflection angle of the hanging rail of the sprayer during the movement was measured.The image of the sprayer’s hanging rail motion was obtained by high-speed photography,and the maximum deflection angle of the hanging rail and the vertical direction was obtained by image processing.The relationship between ground irregularities and the angle of deflection of the sprayer’s suspension rails indicate that the maximum deflection angle increases with the increase of the speed under the condition of the track-laying operation,and the values are 5.3°,5.6°and 5.7°,respectively.In the operating conditions without rail laying,the maximum deflection angle increases significantly with the increase of speed,and the values are 7.9°,8.5°,10.5°.By designing the angle between the hanging rail and the crossbar to be 84.7°,the deflection angle of the hanging rail can be eliminated to meet the actual design requirements.(5)Sprayer performance and influence factors of sediment distribution testsIn the three combined spray methods,the coverage of the reverse side of the leaves did not change significantly.the coverage of the front and back of the high leaves was higher than that of the front and back of the low leaves.In terms of the total amount of spray,the combination of the top spray with two nozzles is greater than the combination of the top spray with one nozzle,and the coverage of the droplets is similar under the two combinations.In order to avoid wasting pesticides,the multi-row sprayer chooses the combination of top spray with one nozzle;compared with the other three working conditions,the coverage with the pressure at 0.5MPa and the speed at 0.8m/s is the highest.