Simulation Analysis And Optimization Of A Seedling Transplanting Mechanism

With benefit to extend the crop growth period, and to improve the seedling survival rate,and to reduce replanting, seedling trans-planting technic is help to increase crop production andeconomic benefits. Due to its advantages of the fast seedlings survival and increase ofproduction, the seedling transplant technique has gotten more and more attention of researchers.Simulation analysis and structural optimization of a seedling transplanting system are carriedout by virtual prototype technique with Pro/E Wildfire5.0and ADAMS2012based on formerdeveloped2ZB seedling trans-planter. Study results are useful technical references to optimizetrans-planter structure and its motion parameters, and to improve performance index. The maincontents are as follows:1. Improvement and3D modeling of seedling transplanting mechanismThe supporting mechanism and the transmission mechanism have been improved basedon analysis of the trans-planter structure and its working principle. Three3D models ofseedling transplanting unit are constructed by Pro/E wildfire5.0. The assembly models of theseedling transplanting unit are designed by combined method of deformation design andbottom-up assembly, and their3D virtual assembly models are developed.2. Virtual prototype modeling and kinematics analysis of the seedling planting mechanismThe virtual prototype models of the seedling transplanting mechanism are established byimporting its CAD model, analyzing its restraint and adding constrains and driving force.According to the corn planting requirements in Northeastern of China, the kinematics analysisof the planting mechanism is conducted. Affects of parameters of the reset spring on thesupporting mechanism motion are studied. With dashpot coefficient0Ns/mm and the preload-5.565N, reset spring can meet the motion requirement of the supporting mechanism. By theinitial phase angle of the cam determined, the effect of the cam tooth number on the supportingplant motion is studied. Initial optimization of the structural parameters and constraintparameters of seedling trans-planting virtual prototype is finished.3. Simulation analysis of seedling transplanting processWith respect to pot corn seedling planting process, simplified models of seedling and soilare set up.3seedling planting system virtual prototype models with different cam gear areconstructed, and their operating simulation analyses are studied to analyses affects of initialangle of seedling plate and cam gear on trans-planting system performance. Simulationanalysis shows that with related initial angle of the cam for a third, initial angle of seedlingplate10°can keep the seedling upright posture in trans-planting process.3trans-plantingsystems with2-teeth,3-teeth, and4-teeth cam can all meet the requirement of keeping theseedling upright posture in trans-planting process. As can meet the condition of0velocity trans-planting, the performance of the trans-planting systems with3-teeth cam is best.