The Design And Optimization Of Transplanting End Effector On TRIZ

As an important part of agricultural industry,transplanting mainly replants seedlings to a new growing place by manual work or mechanical work.It has the climate compensate function,and can advance the crops’ fruit time.At the same time,it can make full use of thermal energy,which has good economic and social benefits.At present,due to the drawbacks of traditional manual transplanting,such as low efficiency transplanting,big demand for labour,the low accuracy of transplanting and so on,automatic,semi-automatic transplanting machine has used more and more in a wide range of applications.As an important component part,transplanting end effector transplanting machine’s comprehensive performance affect directly to the whole efficiency transplanting machine and transplant success rate.TRIZ theory as the invention of the systemic method to solve the problem,analysis and design process by this can realize design rule well,shorten the design cycle,and broadens the thought angle,make the designed product performance better.While TRIZ theory in the design of mechanical products has a certain degree about the popularization and application,but there is no body doing the study on design of transplanting end effector.In view of the above situation,we creatively combine the theory of TRIZ into the design of end effector,a kind of suitable for transplanting machine research were reached at the end of the actuator.First,using TRIZ theory in the material field analysis,general engineering parameter analysis,morphological matrix,inveintion principle to design the overall program planning.After the completion of the mechanical part design,analysis of ADAMS and ANSYS software were aided to complete the static,dynamic characteristics analysis of transplanting end effector.Experiments prototype was built to reach the process of transplanting.At the same time,a transplanting experiment platform was built to realize transplanting.In the end,use the simulation method to optimize a transplanting end effector.Specific research contents and conclusions are as follows:(1)Substance field analysis in TRIZ theory is used to determine the main contradiction in the design of the end effector,and use the 39 general engineering parameters on the seedling selection way,through the morphological matrix determine that its driven by the overall structure of cylinder,bar transmission,three pointer form.By 40 invention principles to determine its working characteristics form,finally by establishing a mathematical model to determine the key structure size,using modular design idea to finish the three-dimensional model’s establishment.(2)The static and dynamic characteristics of transplanting end effector was analyzed by ADAMS and ANSYS software.Based on ANSYS,a finite element model of transplanting end effector was developed and its static characteristic was analyzed.The results showed that the maximum deformation and maximum stress value were 0.08 mm and 133.13 Mpa,meeting the requirements of structural strength;The virtual prototype model of transplanting end effector was developed and pointer trajectory was simulated in the basis of ADAMS,the relative length error between simulation and ideal trajectory is 3.9%.The velocity,displacement and acceleration of transplanting pointer were analyzed under the simulation condition and ideal conditions,and results showed they all met the design requirements.(3)The transplanting end effector was analysed by ANSYS software in a way of free modal simulation,For its physical prototype,according to the LMS vibration tester’s free modal experiment analysis,the transplanting end implements sample tools’ performance is good.Comparing the result of experiment to the freedom simulation’s modal natural frequency,the error is within 15%,which further verify the validity and feasibility of the finite element analysis,and be a bridge for the following analysis optimization.(4)The transplanting experiment platform was structured,the control system hardware was designed,and complete control programming software by using STEP 7-Micro/WIN,and the PC control programming was completed by using the MCGS configuration software to achieve the transplanting process of transplanting end effector.(5)The transplanting end effector’s connecting rod material,transplanting pointer clamping angle and fixed plate structure were optimized by using the finite element simulation analysis method.Static analysis was made in the condition that transplanting pointer clamping angle was 13°,150and 17°and the transplanting pointer clamping angle was optimized from 15° to 13°;Static analysis was made in the condition that connecting rod material was aluminum,45 steel and titanium alloy,and the connecting rod material was optimized from aluminum to 45 steel;Aiming at the problem that the modal frequency of transplanting end effector approached the vibration frequency of test bed because of the structure of original fixed plate,the slot length of fixed plate was optimized from 23mm to 10mm.Results showed that each order of the modal frequency was improved and the first order frequency could avoid test frequency better.