The Research Of Design And Optimization For Propulsive Wheel Of Mobile Robot Based On Electromagnetic Shielding

This work is supported by National Natural Science Foundation ofChina-Trafficability control with low-power consumption toward wheeled robot in roughterrain and Specialized Research Fund for the Doctoral Program of Higher Education ofChina-The Mechanism of Robot Perceptive Wheel and the Structure Optimization inTerms of Multi-physics Couplings. This thesis mainly focuses on the electromagneticshielding characteristics of the propulsive wheel of mobile robot, in order to ensure thecompactness of mechanical structures.Firstly, a kind of propulsive wheel for small sized mobile robot for complex roughterrain condition is proposed by considering its internal electromagnetic characteristicsmade to assure in this research. Herewith electromagnetic shielding theory is proposed,which establishes the parametric model of propulsive wheel based on3D structure andFEM simulation software Ansoft HFSS and ascertains material properties of propulsivewheel in order to provide the reference to complete specific lay-out of mechanical structuredesign. Thus shielding effectiveness of propulsive driving wheel could be one of theimportant performance indices to evaluate the electromagnetic compatibility of thepropulsive wheel.Secondly, the main electromagnetic interference source of propulsive wheel is studied.The equivalent electromagnetic interference source model between the electroniccomponents and electronic equipments is established by analyzing the electromagneticcharacteristics of electronic apparatuses. As the heat sink became source to form thesecondary electromagnetic interference in the propulsive wheel, it can be combined withthe structure of the propulsive wheel with its material properties. The eigenvalues modulusof the Finite Element Method (FEM) used to analyze the main effects of physicalparameters of the heat sink on electromagnetic field inside the propulsive wheel and lay thefoundation to optimize shielding effectiveness for propulsive wheel by optimizing physicalparameters of the heat sink itself.Furthermore, the quantitative relationship between propulsive wheel and shieldingeffectiveness is studied. Analysis and optimization between sources of disturbance on internal electromagnetic field and its mechanical structure of propulsive wheel is carriedout based on shielding effectiveness. The best shielding effectiveness of propulsive wheelis ascertained since the multi-objective function based on approximation model theory andmulti-objective optimization theory is combined to get the optimal solutions. The data isimported from Ansoft HFSS software to iSIGHT software in order to build relationshipsbetween physical parameters of the propulsive wheel and shielding effectiveness, whichagain based on Radial Basis Function (RBF) neural network. By considering the designconstraints of propulsive wheel, multi-objective optimization is used to optimize itsstandards of shielding effectiveness by Non-dominated Sorting Genetic Algorithm-II(NSGA-II) with global optimization. The design variables are determined by analyzing theDesign of Experiment (DOE), which focuses on the main effects and Pareto contributionrate of its physical parameters on shielding effectiveness.Lastly, the optimization software package of shielding effectiveness for propulsivewheel of mobile robot is developed. In early phase, the optimization results from iSIGHTsoftware are integrated into the software package by using MATLAB software. In the nextphase, Harmony Search Algorithm (HS) is compiled with MATLAB software and theapplication program interface is obtained by compiling between MATLAB software andAnsoft HFSS software for the shielding effectiveness optimization of propulsive wheel, andHS is used to develop improved optimization platform of shielding effectiveness forpropulsive wheel. In this manner, software usage patterns for the end users are realized byMATLAB software and the optimization process automation for the shielding effectivenessof propulsive wheel is also realized. Finally, the whole comparison of the optimizationresults between Harmony Search Algorithm and iSIGHT platform is completely analyzed.