With the rapid development of the dwarf dense planting apple orchard planting model in China,a large amount of residues produced after pruning need to be processed by machnization.At present,the traditional methods of manual picking,transportation,and centralized crushing are still the mainstay,and there is also the phenomenon of using straw crushers to replace operations,but the performance of the treatment is not good.In order to achieve mechanized processing between rows of orchards,increase the success rate of ground pruning residues and improve the performance of pruning residue smasher,the picking-up device and its mechanism have been studied in depth.In the link of processing,the performance of the picking-up device directly plays a key role in the effect of the smasher.This article takes the residues produced after pruning under modern orchard planting mode as the work object.According to the technical requirements of agronomic management,the diameter of branches is basically less than 35mm and mainly branches.Such branches are used as the working range of the picking-up device.In order to grasp the change law of the physical characteristics of tree branches under collision,a physical and mechanical characteristics test platform was established.Experiments were carried out on branches of apple,peach and pear,which graphs showing the relationship between elastic modulus and moisture content of branches of different diameters were obtained.The analysis result can help determine the best processing time period and improve the crushing performance of the smasher.In order to test the influence of the forward speed,rotation speed,bending angle of the front end of the spring teeth and the height of the picking position on the picking success rate,a set of test platform with Arduino control technology was designed.Use the single factor test method to test the influencing factors.The analysis results provide a theoretical basis for the optimal design direction of the trimming residue picking-up mechanism.Combining the technical level of domestic mechanized processing of agricultural waste,a set of pruning residue processing integrated machine applied to modern apple orchards is designed,which mainly includes gathering device,picking-up device,slicing and crushing device,filter and collection box.The gathering device can concentrate the scattered residues on the ground to the center of the orchard,expand the working width and improve the success rate of treatment.In order to achieve a better gathering effect,a mechanism that changes the gathering angle is designed.The key component parameters were obtained with movement trajectory by a reversing method.Establish a mathematical model,compile a program,and perform a segmented design for the actions of the components executed in the gathering cycle.The optimization task of structural parameters is completed on the optimization design platform of the gathering device and the ratio of the effective operation range in the complete cycle is increased.The picking-up device can complete the picking-up action of residue.The pair-roller picking-up device,the spring-tooth drum-type picking-up device and the hook-type spring-tooth picking-up device were respectively established mathematical models,built an optimization platform,and performed kinematics simulation.Optimized the design of the key influencing factors,and obtained a set of parameter combinations of the pair-roller picking-up mechanism.Experiments were carried out on apple branches with moisture content between 18%and 27%,and the placement of the apple branches on the ground was arranged.The test results show that the picking-up success rate reaches 92.6%and 89.3%under the chaotic and horizontal conditions,while the success rate is significantly reduced in other positions.It shows that the placement condition has a great influence on the picking success rate and also proves the importance of researching and developing gathering devices.Combined with the test results of branch picking-up,a spring-tooth drum picking-up mechanism is used to meet the requirements of lowing the height of the picking position.Establish a mathematical model and perform kinematic analysis.According to the technical requirements of picking-up actions,the main influencing parameters are optimized by segmented design,programming,motion simulation,and man-machine dialogue,then the results and data processing are analyzed.Finally,a set of optimal parameters are obtained.Using the design method of reverse solving,the data calculation and output of key components are realized in the man-machine dialogue window.Carry out Fourier function multi-segment curve fitting to the shape of key components,and improve smoothness after smoothing.A prototype was manufactured according to the optimized results.Field tests were conducted on apple branches.The test results showed that the success rate of picking-up in a messy state reached 94.2%,which met the technical requirements of picking operations.At the same time,a futher research was carried out on the basis of picking-up test platform.In order to enhance the ability of the spring teeth to feed trimming residues,a hook-type spring-tooth roller picking-up device with a new type of movement trajectory is proposed.It uses hook-shaped spring teeth to produce a "drag"action on the branches,which improves the picking-up performance.Completes the action of separating the branches from the spring teeth through a special motion trajectory.Through the study of the mechanical characteristics of branches,the design method based on human-machine dialogue optimizes the parameters of the gathering,picking-up mechanism,so that the gathering device and the picking-up device can adapt to the physical characteristics of the branches,which solves the problem of low picking-up success rate by traditional picking machines.It provides technical support for the overall design of the orchard pruning residue smasher.The test results proved the correctness of the theoretical analysis. |