Design And Experimental Evaluation On A Shaped Orifice Precision Plot Seeder

The primary task of modern agriculture is a guarantee of enough grain food production and supply.Wheat is a staple food supply in China,which cultivation area and market reserve are both ranked the highest in the world.Field-scale breeding,comparison and superior breed cultivation are the main measures for illustrating wheat performance,cultivation methodology and breeding new species.However,when related scientific experiments were conducted in the field,a major problem remains as to implement effective and precise seeding in a plot.There are two obstacles remain unresolved for wheat seeding in the plots.One is the optimum machine design on precision plot seeder.The other is the quantification of the influential effect of environmental factors on the seeding quality.With respect to the precision plot seeder design,there is a limited class and models of precision plot seeders developed in China.Related research on the influential factors within filed environment on the seeding quality is even more severe.With sufficient considerations on the existing precision plot seeders and extensive concern on the characteristics and requirements of plot seeders,a new method of precision plot seeding was proposed.Following this guideline a belt seeder was designed and fabricated.A field experiment conforming national standard(GBT6973-2005,i.e.,Experimental procedure for single seed(precision seeding)machine testing)was implemented to evaluate the constructed seeding machine.Performance of the seeder as well as the effect of surface soil quality on the seeding quality was evaluated.The experimental result led to a new round of revised machine design,which was then designed and constructed.Then a final field experiment was conducted for the evaluation.The major research works and achievements includes:1.A systematic review on the precision plot seeders both homemade and abroad and a thorough evaluation on their benefits and drawbacks.A new method for precision plot seeding was proposed.A belt-type plot seeder was designed and fabricated.2.Following the specifications enlisted in GBT6973-2005,a national standard for plot seeding experiment,a power transmission and evaluation mechanism was designed and constructed,on which the precision plot seeding cart was assembled.The whole assemblage was mounted on a field experimental platform to facilitate field testing.Qualified index,missing index,clumping index and coefficient of variation were evaluated for different experimental conditions,including 6 theoretical seed to seed distance and 2 forwarding speeds.3.Surface soil effect on seeding quality was evaluated.A profile meter was used to measure soil surface roughness,which was re-generated virtually in Pro/E.Soil surface roughness and seed distribution were analyzed and the correlation between the two was evaluated.4.Adaptable attachments and furrow opening tools were designed and assembled to the seeding cart,with a good conformity to the standard seeding machines.The whole assemblage was used to test seeding in furrows.5.Soil surface effect on seeding quality was evaluated,depending on which a refined precision seeding method(i.e.,punch seeding)was proposed.A precision punch seeding machine was designed and fabricated.6.Power-driving and controlling mechanism was designed and fabricated.The assembled punch-seeding machine was tested in the field,which performance was evaluated.