摘要：In order to meet the agronomy demand for hybrid rice direct seeding,a novel precise pneumatic rice seed metering device was designed with groups of sucking holes plate,by which 3-4 seeds could be synchronously sucked and synchronously dropped into the paddy *** plate was divided into five sections:seed sucking,seed clearing,seed carrying,seed dropping,and blank *** seeds were sucked in sucking section by the vacuum,carried and rotated to the dropping section with the plate,blown away in dropping section by the positive pressure air,and thrown into the dropping *** influences of the hole diameter,vacuum degree,and clear-up equipment on precision of metering device were *** were conducted to investigate the seeding precision and simulate the field emergence rates on the indoor seeding *** subjects were pregnant Indic hybrid Peizataifeng under two kinds of moisture content(23.43%and 26.07%).Other experiment conditions included the vacuum degree of 2.60 kPa,the rotation speed of seed sucking plate of 30 r/min,three sucking holes with a diameter of 1.6 mm,and the seed layer thickness of 25 *** seeding results showed that,in condition of no more than two seeds per hill,the emergence probabilities under the two moisture contents were 11.82%and 11.95%,respectively,and in condition of 3-4 seeds per hill,the results were 64.81%and 65.84%,*** 2-5 seeds per hill,the results were 92.08%and 92.60%,*** the emergence probability was 80%,under the two moisture contents,the no seed per hill probabilities were 1.33%and 0.80%respectively;the probabilities with 3-4 seeds per hill were 56.13%and 56.40%respectively;the probabilities with 5 or more seeds per hill were 10.67%and 10.13%respectively;the probabilities with 2-5 seeds per hill were 87.60%and 88.13%*** results showed the simulated experiment was an efficient and economic method to assess the capability of pneumatic rice seed drilling metering

摘要：In order to optimize the structure schema of flexible comb-type grass seeder,the effects of combing teeth gap L,rotation speed of comb shaft N,seed metering device inclining angle α and groove strip inclining angle θ on the rate and uniformity of seeding were observed by test and analyzed,then the coefficient of seeding stability variation was explored in the simulating planting environment on the soil tank test bed based on the above four influencing factors,with Festuca arundinacea seeds as *** to the results of regression analysis,the model fits well with the actual situation.L,N,α,and the interaction term of N and θ are significant,and the interaction term of θ and α is extremely *** analysis of interaction factor effect shows that the variation coefficient responds to the interaction of N and θ in the same manner as that responds to the interaction of θ and α,showing ‘saddle’ variation *** the acceptable maximum value of coefficient of seeding uniformity variation is 4%,then the inverse proportion relationship between factors is inferred according to the change trend of the above interaction factors and derivation of regression *** the regression equation was simplified according to the inverse proportion equation,and four groups of parameters were *** parameter group was tested,and the test results agreed with the regression equation's predicting value,with the correlation coefficient *** research can provide reference for the development of seed metering devices and grass seeders.

摘要：The precision seeding technique has been developed at full speed along with the continuous development of new agricultural technologies,especially those concerning cultivated *** seed-metering device is the key component of a precision seeder.A ground wheel is used to drive the seed-metering device of the conventional direct ***,the wheel bears high resistance and easily ***,the adjustment of the precision seeder’s seeding rate is more *** order to solve these problems,a control system which could keep the rotational speed of the seed-metering device consistent with the seeder’s working speed for the precision seed-metering device was *** control system includes a Hall sensor,a single chip microcomputer system,a motor control module,a stepper motor and a *** control system used a Hall sensor to measure the seeder’s working speed and employed a single chip microcomputer system to predict the rotational speed of seed-metering *** would then determine the relationship between the seeder’s working speed and the rotational speed of the seed metering-device according to the seeder’s working state,distance between seeds and the requirement of sowing *** system could effectively reduce the influence of inhomogeneous sowing caused by the ground wheel’s *** system was found to be reliable by the *** seeding control system could also make the speed of the seed-metering device and seeder’s uniform,improving the uniformity of the amount of seeding,and achieving the goal of *** new design provides a platform to solve problems of the seed-metering device and the seeder.