Design Of Apple Tree Branch Pruning Manipulator

Agricultural robots are the development direction of intelligent agricultural equipment in the future.At present,robot technology has penetrated into all fields and links of agricultural production,especially in fields that require a lot of labor.In the field of forest and fruit production,the degree of mechanization in various links such as soil tillage,fruit tree management,plant protection and irrigation,and harvesting is getting higher and higher.The complexity and diversity of operation objects are becoming more and more obvious,and the trend of intelligence is becoming more and more obvious.Agricultural robot has become the research emphasis and development direction in this field.Pruning is an important part of fruit tree management.It is technical and labor-intensive,but it is still mainly manual operation.For this reason,this paper takes apple tree pruning as the work object,and proposes a wrist-biased 6-DOF(six-degree-of-freedom)articulated manipulator according to the needs of apple tree pruning and shaping,so as to improve the efficiency of apple tree pruning and shaping and reduce labor intensity.The main research contents of this paper include the following aspects:(1)The configuration selection of the pruning manipulator and the determination of the component size parameters.Starting from the specific requirements of apple tree pruning,the configuration of the positioning mechanism and the posture adjustment mechanism of the manipulator was synthesized,and the size parameters of the manipulator were preliminarily investigated by investigating the growth characteristics of apple trees.(2)Kinematics analysis of the pruning manipulator.The forward kinematics modeling of the manipulator is carried out by the MDH(Modify Denavit Hartenberg)method and POE(Product Of Exponentials)method,and the error analysis of the output results is carried out to verify the correctness of the forward kinematics model by building a comparative model through MATLAB/Simulink.The particle swarm algorithm based on simulated annealing is used to model the inverse kinematics of the manipulator without analytical solution,and the practicability and accuracy of the inverse kinematics algorithm are verified by simulation experiments.(3)Kinematic performance analysis of the pruning manipulator.Based on Monte Carlo simulation,the work space analysis of the pruning manipulator was carried out,and the singular configuration and flexibility of the pruning manipulator were also analyzed to verify the rationality of the component size of the pruning manipulator.Finally,the simulation of the manipulator’s ability to prune branches in different growth directions by flexibly adjusting the position and posture under a small space requirement is carried out.(4)Pruning manipulator dynamics analysis.The 3D(three-dimensional)model of the manipulator is created in Solidworks and then imported into ADAMS for dynamics simulation.The simulation results provided the reference for the design of the manipulator joint drive.(5)Structural design of the pruning manipulator.Combined with the kinematics and dynamics analysis of the manipulator,the structural design and driver selection design of each joint of the manipulator are carried out.