Walnut Tree Modeling And The Design Of Fruit Picking Machine

In recent years,the rapid development of fruit industry in China,especially the walnut industry has a huge development.walnut planting area and production are in the forefront of the world.Due to our special planting terrain,picking season in walnut on the mechanical harvesting machine requires a higher level of operation,however,most of the current low efficiency of manual picking has caused have harvest but no harvest.Furthermore,the introduction of foreign domestic large equipment can not adapt to Chinaese intensive dwarf walnut planting pattern,in this world full of competition in the era of rapid development of all walks of life,development of eccentric vibration for domestic walnut planting mode of picking machine is of great significance for the development of the walnut industry.In this paper,based on the principle of theoretical mechanics,the vibration model of the picking machine with damping and elastic system is established.Through analysizing to calculate the walnut fruit body and fruit stalk separation conditions by the force.According to the morphological and biological characteristics of walnut trees by Pro/e three-dimensional that modeling of the fruit tree,the fruit and fruit stalk elements are added to the model,to the Ansys and harmonic analysis to study the relationship between the holding height and applying vibration force and deformation response of the tree is suitable for picking at the height of 900mm above the ground and suitable excitation force is about 3000N and model into Ansys software.Also by selecting the suitable picking point and exciting force on stress response analysis of different walnut maturity for harvest frequency,the conclusion is the best in 70%mature fruit picking frequency is 28.6Hz,80%mature is 26.3Hz,90%mature is 24.0Hz,fully mature is 21.3Hz.Based on the above analysis,the eccentric walnut vibration picking machine is designed.The utility model mainly comprises an eccentric vibration exciter,a clamping device,a multi degree of freedom mechanical picking arm and a walking system.Focus on the design of key parts of the eccentric block and its static analysis and modal analysis.According to the needs of the eccentricity of the eccentric block design is 10.25kg m.The clamping mechanism is designed to be surrounded by clamping to increase the contact area with the trunk to reduce the damage to the bark.Picking arm designed to 6 degrees of freedom to achieve a wide range of efficient harvesting.The design of crawler type independent walking device to adapt to the terrain and in the intensive planting mode.Through the static and modal analysis of the eccentric block,the feasibility of the design of the core components is verified.The final ADAMS dynamic simulation of picking machine-tree,found that the rotation of the eccentric block running at the same speed trunk centroid acceleration ratio and speed should be large,so that the same speed energy conversion rate is higher than the speed of the conversion rate from the motion trajectory of the same speed than the speed and steady,so overall rotate at the same speed vibration effect is better than the speed of different situation also verified the feasibility of the design of vibration picking machine.