Design And Development Of Orchard Ditching And Fertilizing Machine

China is a big fruit country in the world.With the continuous development of the forest and fruit industry,it is necessary to reduce the burden of fruit farmers,improve the quality of fruit,increase the efficiency of fertilization,and eat safe fruit for the common people.The forest and fruit industry needs mechanization and intelligence.Let technology lead the development of the fruit industry.Fertilization is the key link of fruit quality,and scientific and reasonable fertilization depends on the degree of mechanization and intelligence of the orchard.At the same time,due to the high degree of the aging population,the obvious shortage of labor force,the heavy workload of orchard deep furrow fertilization,the low efficiency of artificial fertilization,and the delay of agricultural hours,to improve the productivity of orchard,this paper proposes a new intelligent furrow fertilization machine.(1)According to the actual work requirements of the orchard,especially the gardening requirements of fertilizing and ditching,the design parameters of ditching fertilizer were determined,including fertilizing position,fertilizing precision,ditching width,ditching depth,vehicle forward speed,power consumption,etc.To ensure the power,economy,and reliability of vehicles and furrow fertilizer,determine the overall scheme of precision control fertilizer for fruit trees,and select the matching tractor.The mechanization level and fertilization status of the orchard were evaluated and discussed,and a precision fertilization scheme of mixed variable rate fertilization with strip furrow intermittent and continuous furrow was put forward.(2)The main working system and parts of the furrow fertilizer are analyzed and studied.The structure is designed and the overall assembly is completed by using the three-dimensional drawing software(Solid Works).According to the actual requirements of the orchard,based on the above overall structural requirements,combined with the kinematic and dynamic analysis of fertilization device and ditching device with the influence parameters of fertilization and ditching,the outer grooved wheel fertilizer distributor with the diameter of 65 mm,the length of 65 mm and the number of 6 grooved wheels was determined.The ditching structure parameters,main operation parameters,and ditching power consumption were analyzed,and the ditching depth was determined to be200 mm,The rotary diameter of the ditcher is 450 mm,and the number of the ditcher is 8.(3)Based on machine vision and deep learning,the tree trunk was identified to accurately fertilize.The basic theory of the camera is analyzed,including the coordinate system,imaging principle,and binocular vision principle.Then the traditional visual processing based on Open CV Python is carried out,including image denoising,image pixel threshold,open-close operation,and image area threshold.Because the traditional visual processing effect is not ideal,another 556 trunk images are collected to complete the image data set enhancement.The images are marked with labelme.The algorithm based on Mask R-CNN deep learning runs in a Tensorflow environment,and the total loss function of model training is reduced to less than 0.1.The average recognition accuracy of the trunk is more than 99.48%,and the recognition effect of the darkened images is the best.Finally,the center coordinates of the trunk region are extracted from the trunk segmentation map,and the fertilization location verification test is carried out by the coordinate transformation relationship,and the fertilization location accuracy meets the requirements.(4)The software and hardware of the orchard ditching fertilizer machine were designed,and the control scheme of the stepping motor was determined.The hardware connection of the control system was completed.Taking Getac series industrial computer as the core component of the control system,the power module,communication module,drive module,and fertilization module are designed or selected.At the same time,the relationship between the stepping motor and fertilizer exhauster is established,and the relationship between motor pulse number and vehicle speed is determined.Control system software design.By using MFC(Microsoft Foundation classes)programming,the fertilization program of stepper motor is programmed,binocular visual image acquisition,image processing,prediction of trunk position,the establishment of fruit tree position coordinates under the coordinate of fertilizer exhauster,setting fertilization length and amount,determining the beginning and end positions of fertilization,turning on the motor when reaching the beginning position of fertilization,and turning off the motor at the end,To achieve the purpose of accurate variable fertilizer discharge,the software design of control system is realized.(5)Test results and analysis.The results show that the coefficient of variation of fertilizer discharge consistency is mainly 2% ～ 4%.At 45 r / min,the average coefficient of variation of fertilizer discharge consistency is 2.5% for nitrogen fertilizer,3.1% for phosphorus fertilizer,and 2.6% for potassium fertilizer,respectively.The effect of fertilizer discharge is better.The least-square method was used to solve the functional relationship between different fertilizer discharge amounts and fertilizer discharge speeds,and python was used to draw the fitting curve.The experiment of automatic fertilization includes fertilization position,fertilization amount,and fertilization length.The results of the orthogonal experiment show that the error of fertilization amount is small when the speed is0.5km/h,the fertilization amount is 500 g and the fertilization length is 65 cm.When the speed is 0.5km/h,the amount of fertilizer is 1400 g and the length of fertilizer is 75 cm,the length error is the smallest.