Structural Optimization of a Knuckle with Consideration of Stiffness and Durability Requirements

The automobile’s knuckle is connected to the parts of the steering system and the suspension system and it is used for adjusting the direction of a rotation through its attachment to the wheel. This study changes the existing material made of GCD45 to Al6082M and recommends the lightweight design of the knuckle as the optimal design technique to be installed in small cars. Six shape design variables were selected for the optimization of the knuckle and the criteria relevant to stiffness and durability were considered as the design requirements during the optimization process. The metamodel-based optimization method that uses the kriging interpolation method as the optimization technique was applied. The result shows that all constraints for stiffness and durability are satisfied using A16082M, while reducing the weight of the knuckle by 60% compared to that of the existing GCD450

Multi-objective optimization design for a battery pack of electric vehicle with surrogate models

In this investigation, a systematic surrogate-based optimization design framework for a battery pack is presented. An air-cooling battery pack equipped on electric vehicles is first designed. Finite element analysis (FEA) results of the baseline design show that global maximum stresses under x-axis and y-axis transient acceleration shock condition are both above the tensile limit of material. Selecting the panel and beam thickness of battery pack as design variables, with global maximum stress constraints in shock cases, a multi-objective optimization problem is implemented using metamodel technique and multi-objective particle-swarm-optimization (MOPSO) algorithm to simultaneously minimize the total mass and maximize the restrained basic frequency. It is found that 2nd order polynomial response surface (PRS), 3rd order PRS and radial basis function (RBF) are the most accurate and appropriate metamodels for restrained basic frequency, global maximum stresses under x-axis and y-axis shock conditions respectively. Results demonstrate that all the optimal solutions in Pareto Frontier have heavier weight and lower frequency compared with baseline design due to the restriction of global maximum stress response. Finally, two optimal schemes, “Knee Point” and “lightest weight”, satisfied both of the stress constraint conditions, show great consistency with FEA results and can be selected as alternative improved schemes

Structural optimization of MacPherson control arm under fatigue loading

U ovom istraživanju izvršena je optimizacija topologije i oblika MacPherson upravljačke poluge u svrhu postizanja manje težina. Postojeće automobilsko tržište traži dijelove niske cijene i male težine, a za potrebe energetski učinkovitog, a jeftinog vozila. To zahtijeva učinkovitiju uporabu materijala za automobilske dijelove koji mogu dovesti do smanjene mase vozila. Budući da su automobilski dijelovi izloženi dinamičkim opterećenjima koja uzrokuju oštećenja zbog zamora, uzimanje u obzir kriterija zamora čini se bitnim u dizajniranju automobilskih dijelova. Kako bi se stvorili što teži uvjeti opterećenja upravljačke poluge, najprije su spektralnom gustoćom snage generirane neravne ceste. Zatim su, dinamičkom analizom karoserije kompletnog modela vozila, dobiveni najkritičniji uvjeti opterećenja. Nakon toga, izvršena je optimizacija topologije pomoću kriterija vijeka trajanja do zamora primjenom HyperMesh softvera, što je rezultiralo smanjenjem mase od 50 %. U sljedećem koraku kreiran je CAD model primjenom CATIA softvera i provedena optimizacija oblika kako bi se dobile točne dimenzije s manje mase.In this research, the topology and shape optimization of a MacPherson control arm has been accomplished to achieve lighter weight. Present automotive market demands low cost and light weight component to meet the need of fuel efficient and cost effective vehicle. This in turn gives the rise to more effective use of materials for automotive parts which can reduce the mass of vehicle. Since automotive components are under dynamic loads which cause fatigue damage, considering fatigue criteria seems to be essential in designing automotive components. At first, in order to create severe loading condition for control arm some rough roads are generated through power spectral density. Then, the most critical loading conditions are obtained through multi body dynamics analysis of a full vehicle model. Then, the topology optimization is performed based on fatigue life criterion using HyperMesh software, which resulted in 50 % mass reduction. In the next step a CAD model is created using CATIA software and shape optimization is performed to achieve accurate dimensions with less mass

Structural optimization of MacPherson control arm under fatigue loading

U ovom istraživanju izvršena je optimizacija topologije i oblika MacPherson upravljačke poluge u svrhu postizanja manje težina. Postojeće automobilsko tržište traži dijelove niske cijene i male težine, a za potrebe energetski učinkovitog, a jeftinog vozila. To zahtijeva učinkovitiju uporabu materijala za automobilske dijelove koji mogu dovesti do smanjene mase vozila. Budući da su automobilski dijelovi izloženi dinamičkim opterećenjima koja uzrokuju oštećenja zbog zamora, uzimanje u obzir kriterija zamora čini se bitnim u dizajniranju automobilskih dijelova. Kako bi se stvorili što teži uvjeti opterećenja upravljačke poluge, najprije su spektralnom gustoćom snage generirane neravne ceste. Zatim su, dinamičkom analizom karoserije kompletnog modela vozila, dobiveni najkritičniji uvjeti opterećenja. Nakon toga, izvršena je optimizacija topologije pomoću kriterija vijeka trajanja do zamora primjenom HyperMesh softvera, što je rezultiralo smanjenjem mase od 50 %. U sljedećem koraku kreiran je CAD model primjenom CATIA softvera i provedena optimizacija oblika kako bi se dobile točne dimenzije s manje mase.In this research, the topology and shape optimization of a MacPherson control arm has been accomplished to achieve lighter weight. Present automotive market demands low cost and light weight component to meet the need of fuel efficient and cost effective vehicle. This in turn gives the rise to more effective use of materials for automotive parts which can reduce the mass of vehicle. Since automotive components are under dynamic loads which cause fatigue damage, considering fatigue criteria seems to be essential in designing automotive components. At first, in order to create severe loading condition for control arm some rough roads are generated through power spectral density. Then, the most critical loading conditions are obtained through multi body dynamics analysis of a full vehicle model. Then, the topology optimization is performed based on fatigue life criterion using HyperMesh software, which resulted in 50 % mass reduction. In the next step a CAD model is created using CATIA software and shape optimization is performed to achieve accurate dimensions with less mass

DETERMINAÇÃO DAS FORÇAS ATUANTES EM UMA SUSPENSÃO DUPLO “A” EM AMBIENTE MULTICORPOS

O presente trabalho consiste na modelagem multicorpos de uma suspensão automobilistica independente do tipo Duplo “A” utilizada no veiculo de competição minibaja da equipe Piratas do Cerrado da Universidade de Brasilia. Neste sentido, são avaliadas as forças lateral, longitudinal e normal atuantes na bandeja inferior deste subsistema a partir da análise dinâmica que considera a relação pneu- pista como principal fonte de excitação do protótipo, a fim de verificar quais dessas forças são mais relevantes para determinação do histórico de carregamento deste componente

Multiobjective design optimization of IGBT power modules considering power cycling and thermal cycling

Insulated-gate bipolar transistor (IGBT) power modules find widespread use in numerous power conversion applications where their reliability is of significant concern. Standard IGBT modules are fabricated for general-purpose applications while little has been designed for bespoke applications. However, conventional design of IGBTs can be improved by the multiobjective optimization technique. This paper proposes a novel design method to consider die-attachment solder failures induced by short power cycling and baseplate solder fatigue induced by the thermal cycling which are among major failure mechanisms of IGBTs. Thermal resistance is calculated analytically and the plastic work design is obtained with a high-fidelity finite-element model, which has been validated experimentally. The objective of minimizing the plastic work and constrain functions is formulated by the surrogate model. The nondominated sorting genetic algorithm-II is used to search for the Pareto-optimal solutions and the best design. The result of this combination generates an effective approach to optimize the physical structure of power electronic modules, taking account of historical environmental and operational conditions in the field