Research And Design On A New Type Of Optical-Mechanical-electrical Integrative Seed-metering Device For Carrot

Carrot is one of the most important economic crops in china,and China is the biggest country in carrot production.At present,artificial seeding or simple drill seeding are widely used in carrot cultivation across the country.In this way,it is time-consuming,laborious and seed-consuming.Besides,it is difficult to guarantee the quality of sowing.With the increase of labor costs and seed price,the low level of mechanization sowing has seriously restricted the development of carrot industry.The features of carrot seeds are small size,irregular shape and big brittleness.Besides,carrot seeds need sowing accurately.Mechanical metering device can not meet the requirements of precision sowing.The device is prone to be clogged and the seeds may be damaged.The suction holes of the air-suction seeding device are prone to be clogged.Than periodic leakage of seeds may happen.In current carrot industry,it has become a problem urgently to be solved to research seeding technology and equipment for carrot seeds.This paper proposes a new seeding principle applying optics and mechatronics to achieve sowing function.And an optical-mechanical-electrical integrative carrot seeding device was designed.It can realize single grain precision sowing of carrot seeds,and solve the problem of sowing device blockage and seeds damage,providing a reference of mechanical precision sowing for other vegetable seeds with small size.The main research contents and results are as follows:(1)The working process of the seeding device is like this:a small amount of seeds are outputted intermittently,then the seeds are dispersed.The position of single seeds are determined by image recognition.Then the single seeds are sorted out one by one.Finally,the discontinuous seed flow sorted out is transformed into a continuous seed flow,sowing seeds into the ditch at regular intervals at the same time.(2)A seed pusher has been designed.It can intermittently output a small amount of seeds fast.Filled.,cleaned and dropped by gravity and inertia,the seeds have less damage.A seed sorter has been designed.Seeds are dispersed by high pressure gas controlled by electromagnetic valve.The location of single seeds can be determined through image recognition.Then the single seeds are sorted out sequentially by multiple sets of double-rocker mechanism driven by electromagnet.A seeds transmission device has been designed.Each link of toothed roller chain fixes an inoculation box.The sprocket shafts are fixed to slides,so the chain mechanism can move left and right in the seeding device.The toothed roller chain is controlled by two stepper motors.The inoculation boxes on the upper part are inoculating seeds intermittently,while the inoculation boxes on the lower part are sowing seeds continuously.So the discontinuous seed stream is transformed into continuous seed stream.(3)The airflow field in the dispersion chamber was numerically simulated using FULENT software.The three-dimensional model of the seeding device was established using SolidWorks software.COSMOS Motion plug-in was used for kinematics simulation of the model.(4)An image recognition system was established based on PC platform.The recognition program was written using MATLAB software.The system can quickly and accurately determine the number of holes which exists single seeds.(5)AT89C52 micro-controller was used as the controller of the metering device.Keil development system was used to design the C language controlling program.And the hardware and software were simulated using Proteus simulation software.