Design And Research Of A Safflower Picking Device Based On A Parallel Manipulator

As an important dryland crop in Xinjiang,safflower has high value in economy.However,the current safflower picking operation still needs to be completed by a lot of manual work,which is difficult to achieve the picking effect of economical timeliness.In addition,the existing safflower harvesting machinery is basically semi-manual or mechanical blind harvesting,the demand for labor is large and the impurity rate of filaments is high.Therefore,the market urgently needs an intelligent picking device to reduce the demand for manual labor,improve the harvesting efficiency,and realize the automatic and intelligent picking target of safflower.In this paper,by summarizing and analyzing the research status of safflower harvesting machinery,agricultural picking robots,and parallel robots at home and abroad,combined with the agronomic requirements of safflower planting in my country,a safflower picking device based on parallel robotic arms is developed and designed.Its main research contents are as follows:(1)The overall design scheme of the safflower picking device based on the parallel manipulator is proposed,and the design and analysis of the key components,the parallel manipulator and the end picking device,were carried out.Firstly,the structural parameters of the parallel manipulator were preliminarily determined and a 3D model was built.;then the kinematics model of the parallel manipulator is established by using the vector method,through which the inverse kinematics,velocities,accelerations and singularities of the robotic arm were analyzed in detail;based on the MATLAB simulation software,the three-dimensional simulation analysis of the parallel manipulator workspace is completed by using the Monte Carlo method,and the three-dimensional image is drawn;according to the analysis of the physical characteristics of the safflower,The design scheme is proposed,the crank chute shearing device is proposed and the kinematics analysis is carried out.(2)Based on the general control mode of PC + lower computer,the overall design scheme of the motion control system is determined;the hardware selection is carried out according to the requirements of the design scheme,and the specific control scheme design is further carried out according to the electrical components,among which the motion controller,CAN communication protocol,servo control system,parallel manipulator,and limit switch are the main components in the motion control system;On this basis,the programming of the main modules of the control system,such as the coordinate conversion program module,the motor driver module and the safflower picking program module,was completed..(3)The verification analysis of the parallel manipulator was carried out,and the results verified the correctness of the inverse kinematics mathematical model;a "linear" motion trajectory was designed,and the absolute linear motion command Move Linear Absolute was used to control the motion of the manipulator;To ensure the positioning accuracy,the absolute zero point correction and error calibration tests were carried out,and the average spatial position coordinate error was 2.39 mm,and the results showed that the accuracy met the experimental requirements;finally,the picking verification test was carried out,and the average picking success rate was 76.6%,which verified that the design of the safflower picking device based on parallel manipulators meets the requirements of automatic safflower picking..