| Pomegranate is considered as a symbol of auspiciousness,reunion,and prosperity in culture,and is one of the important elements of traditional Chinese culture.With the improvement of people’s living standards,pomegranate has also become a fruit that loved by more and more people,and the market demand is increasing year by year.However,traditional pomegranate picking and grading work rely on manual operation,which not only consumes a lot of labor costs but also has low efficiency,and is easy to cause damage to the fruit,resulting in loss and waste.Therefore,innovative pomegranate production technology is very necessary.This article designs an aerodynamic flexible gripper for pomegranate fruits based on the geometric model and damage characteristics of pomegranate,and conducts research on its development and grasping performance.The main work contents are as follows:(1)This article studies the problem of low efficiency and easy damage to fruit in the manual operation of pomegranate picking and grading,and an aerodynamic flexible gripper was proposed to solve these problems.The study found that the grip of pomegranate requires the gripper to be flexible,adaptive,and low-damage,so a four-finger enveloping gripping scheme was adopted,and it was found that the gripping force of flexible fingers should not exceed the maximum damage compression force of pomegranate.(2)By selecting the material of the flexible gripper and determining the relevant material parameters of silicone through uniaxial tensile test,the constitutive model of the material was established.Then,the aerodynamic drive mode with strong adaptability was selected,and the structure size and restriction layer structure of the fingers were designed.The optimal combination of structural parameters was obtained through experimental analysis.The results showed that the relatively hard material of type 4030 silicone with a 3mm thick restriction layer had the best bending and fingertip mechanical performance for the aerodynamic flexible fingers.(3)Finally,through experiments on pomegranate gripping,friction experiments of surface-enhanced mechanisms,gripping force experiments,and gripping stability experiments,the influence of surface-enhanced structures on gripping performance was analyzed,and it was proved that the designed aerodynamic flexible gripper in this article can effectively and stably achieve non-destructive gripping of pomegranate.The aerodynamic flexible gripper introduced in this article can be used to efficiently,accurately,non-destructively,and stably grip pomegranate.The use of this gripper can provide new methods and tools for the automation of pomegranate fruit sorting,loading,packaging,and other processes,and also provides reference value for the application of flexible grippers in agriculture. |
