Research On Key Technology Of Flexible Pneumatic Hand Agricultural Robot

Flexible pneumatic hand had become the hotspot of studies on agricultural fruit-picking robot because of its high performance.The flexible pneumatic hand was designed,which was based on the properties of its Ninja Flex material,to coordinate with the robotic arm,and picking-robot based on it was implemented.The research contents were as follows:1)Structure design of flexible pneumatic hand.a)With the apple as experimental material,physical properties and compression-resistant behaviors were analyzed,and the range of crawl scope of the flexible pneumatic hand was determined,which was from 70mm?90mm,according to its physical properties b)The number of fingers of the flexible pneumatic hand was determined to be 3,according to the grasping characteristics of the sphere and distribution of interval between the fingers is 120°.c)The driving mode adopted was determined as pneumatic driving,by comparing and analyzing the advantages and disadvantages of common driving modes of flexible pneumatic hand.d)The 3d model of the flexible pneumatic hand was built in Solid Works 2014 and distribution passage and the method of air inlet were designed in the way of air tightness.2)Finite-element analysis of flexible finger.a)The flexible finger was analyzed by finite element method based on ABAQUS 16.04,the pressure range of the flexible pneumatic hand in normal operation was determined to be-100 k Pa?100k Pa;b)The length of the finger was determined to be 75 mm by comparing the bending deformation of fingers of different lengths and the properties of the fingertip contact force,and the fingertip displacement curves of 75 mm fingers at normal pressures were studied.3)Control system design of harvesting robot.a)The overall control system of the harvesting robot was designed;b)The pneumatic circuit was designed,then the interface between the manipulator and the flexible pneumatic hand was designed;c)The robot system software was designed.The upper computer interface was designed based on VB,and the communication protocol between the flexible pneumatic hand and the upper computer was formulated,and the communication between the upper computer and the robot arm was realized based on ORiN2;d)the picking of the flexible hand claw was realized through the secondary development of the controller of robot arm.4)Experimental research.a)The bending deformation,contact force and grasping force of the flexible finger were tested.The grasping force and the deformation of the flexible pneumatic hand was increased when the air pressuring increasing,and the grasping mass of the maximum grasping force was 368g,which could be showed from the result of the test.b)The feasibility of picking method was verified through the picking experiment of flexible hand,which was based on the harvesting robot platform,and the picking effect was optimal when the breaking method was to be folded upwards by 40°for the wrist.