Design And Research Of Targeted Hole-pricking And Deep-application Fertilizer Applicator Between Maize Rows

Maize is a kind of multi-purpose crop that can be used as food,fodder,industry materials and source energy,both the plantation area and gross output of maize rank the first globally among all crop variaties.It is an important approach to guarantee the food security and promote increase in both production and income by increasing the maize per unit area yield and total yield?Huge bellbottom period of maize is the period when maize grows most rapidly and is in the maximum demand of nutrients.Topdressing in huge bellbottom period has a decisive influence on increasing maize yield.However,manual topdressing and topdressing carried out by small sized fertilizer applicator were widely applied because it is difficult for machines to work between rows of the high maize plant during huge bellbottom period,which resulted in sever waste and environmental pollution due to the low topdressing efficiency and fertilizer use efficiency.Therefore,a targeted hole-pricking and deep-fertilization fertilizer applicator between maize rows was designed based on the agronomy requirements to deal with the above problems.A feasible topdressing configuration and conditions for targeted-pricking between maize rows were studied,meanwhile,structure design and parameter optimization for each key component were also conducted.Finally,field tests were carried out to analyze the topdressing performance of the designed fertilizer applicator.The main conclusions and achievements are as follows:(1)Mechanized maize site-specific topdressing technique has been studied for the first time,and a locating device for topdressing was designed as well.An experiment in orthogonal design was carried out to investigate the influences of fertilization date,fertilization depth,distance of fertilization point and maize plants on maize growth and yield.An optimal combination of the above parameters was determined and a locating device based on this combination.Detection for maize plant,signal transmission,power transmission and the principle of site determination were analyzed;the calculated theoretical location for topdressing was 109-125 mm away from maize plant,depth of fertilization was 80?100 mm,length of proof stick was 100 mm,length of crank was 70 mm,length of connection rod was 150 mm,length of hole pricker was 566 mm.A simulation was conducted for the movement locus of the vertices of pricker using Matlab,the result indicated that pricking depth of hole pricker was 100 mm,and it moved vertically below ground without horizontal displacement,which met the requirement of vertical pricking and zero velocity distributing.(2)Through analyzing the basic conditions and principles of targeted deep-application fertilizer among corn rows,a targeted hole-pricking and deep-application fertilizer applicator between maize rows was designed,and its general structure and basic working principle were introduced.The key components,hole-picking control mechanism,compensation mechanism of horizontal displacement and hole-picking and deep-application fertilizer mechanism,were parametric designed and optimized.Through checking the static strength and service life of these key components by finite element analysis software,it showed that the static strength and service life can meet the requirements of fertilizing.The motion locus of drill point of hole-pricker was simulated using Matlab software,the results showed that the hole-picker was basically a vertical motion under the surface and there was no horizontal displacement,which meet the requirements of zero-speed fertilizering.(3)A new batch type fertilizer device was designed,the simulation model of this fertilizer device was conducted,and the fertilizing performance of the device and the movement of fertilizer particles in fertilizer wheel was analyzed.The structural parameters of each fertilizer device was optimized,the thickness of block was determined to be 5 mm,and the rotation angle of fertilizer wheel was 120°,the amount can meet the requirements of 3-15 g in a single fertilizing hole.(4)Based on the structural principle of the key functional components,the targeted deep-application fertilizer among corn rows was designed;The main structure and working principle were introduced.The time series analysis of the moving parts of the top dressing unit and vibration analysis of the main moving parts were carried out.The results shown that the functional components of the top dressing machine met the design requirements,and it was supposed to solve the problems of difficulty in mechanization top dressing between during middle and late stage of maize growth.Two papers and one invention patent were published.(5)The field test of the targeted hole-pricking and deep-application fertilizer applicator showed that missing rate,vertical amplitude and path offset increased with the increase of forward speed of fertilizer applicator,which means the fertilization depth and the distance between hole and corresponding plant was unstable.Therefore,considering the topdressing stability and working efficiency of fertilizer applicator,the preferred forward speed was about 0.8 m/s.