The Measure And Analysis Of Seed Bounce And Rolling Displacement After Touching Soil On Furrow Opener Of Single Disk

The precision planting is an advanced planting method, a necessary way toachieve agricultural modernization and also one important of steps to increase cropyield, income, and decrease cost of grain production.The precision planting provides accurate placement of seeds to soil at equalinterval within rows, seed depth;it is a complicated procedure composed by profilemodeling, ditching, fertilizing, planting, covering and suppressing;the requests ofits field performance are quite high;its design is difficult and cost of itstrial-manufacture and field test is expensive. So the most popular design modelpresently utilized is through repeated field practice then ameliorating defect to theperfect design. Since long time ago scientists have studied hard on fundamentaltheory of precision planting, but most of their researches focus on whether seedsare given in an even manner by ejector, a simulation research of seeds distributionin field by Monte Carlo theory(statistic simulation method), and theoreticalanalysis of single component and practical experiment of whole machine. All ofthese researches studied little on the position change of the seed ,the displacementof seed bounce and rolling after its touching soil in analyzing seeds distribution infield using precision planting machine. JiLin Industrial University has modeled andcalculated the displacement of seed bounce and rolling after its touching soil, butonly analyzed the procedure in static view.The displacement of seed bounce and rolling after its touching soil wasstudied using furrow opener of single disk. on the basis of consulting a sheer bulkof internal and foreign literatures about precision planting and furrow opener, thecross section model of channel furrowed with the furrow opener of single disk wasbuilt in the procedure;and within this model the influence factors of seeddisplacement of bounce and rolling were analyzed in the reference of abear-strength model of tray. Experiment setting was designed under the theory oftesting design to determine of the displacement of soybean and corn seed bounceand rolling recorded with high-speed video system. The math model was set upwith analysis of the experiment results and the good range of experimentparameters were also concluded within this model.In practice, with the help of cross section model it could be judged whetherthe channel furrowed with the furrow opener of single disk was suitable for theseed and with the math model it could be evaluated the displacement of seedbounce and rolling. With these evaluations and the good range of experimentparameters, they will help to improve planting accuracy and increase crop yield.Following are results:1. Applying transform of space tri-dimensional coordinate, a cross sectionmodel of furrow was established by single disk opener.cos2α0(2hsinα0cosγ0-b)2+4sin2γ0(h-R)2=4cos2α0sin2γ0R2Where :R -radius of single disk;γ0 -working departure angle;α0 -working obliquity;h -depth of furrow;b -width of furrow。2. On the basis of cross section model of single disk opener and consideringthe its force model, the influences factors after seed touching soil were analyzed;they were working obliquity, departure angle forward velocity of planter, andhumidity of soil;these factors will affect the displacement of seed bounce androlling.3. Priority of factors in experiment was analyzed by experiments,departureangle of single disk opener was the most important parameter ,then was the drivingvelocity of planting machine, working obliquity and the soil humidity. Interactionof departure angle and working obliquity was the only marked factors whichinfluence the displacement of seed bounce and rolling after its touching soil.4. The soil humidity is an important factor influenced the displacement of seedbounce and rolling after its touching soil. the higher of its value, the smaller of itsdisplacement as theory described, but in experiment it was find that paranormalhumidity of soil will influence the working of furrow and the shape quality ofchannel, so it must be set in a reasonable range in reality, it can decrease thedisplacement of seed bounce and rolling with proper soil humidity.5. With the theory of uniform design, the experiment was arranged to analyzehow working obliquity, departure angle and driving velocity of planting machineinfluence the displacement of the seed bounce and rolling. The math models wereconstructed in the support of the experiment results.The model for the displacement of soybean bounce and rolling after touchingsoil:Y=1.45×10-3 X23+0.013 X12X3-9.19×10-3 X32X2-1.19 X1+0.012X3+45.07The model for the displacement of corn bounce and rolling after touching soil:Y=1.26×10-3 X23+0.012 X12X3-8.46×10-3 X32X2-1.14 X1+0.069 X3+25.576. The good range of experiment was concluded after analysis of the mathmodels of the displacement of seed bounce and rolling after its touching soil. Thereasonable range of working obliquity of single disc is 6o～9o.the reasonable rangeof departure angle of single disc is 7o～10o.