A GA Based Configuration Design Optimization Method

2004 ◽  
Vol 126 (1) ◽  
pp. 6-15 ◽  
Author(s):  
Pierre M. Grignon ◽  
Georges M. Fadel

This work presents a methodology for optimizing multiple system level assembly characteristics of complex mechanical assemblies by placement of their components. It addresses any component shape (including nonconvex, hollow, sharp edges) connected together by functional constraints. This method presents the designer with multiple solutions to the engineering configuration design problem (ECDP) using a Pareto Genetic Algorithm working on a population of sets instead of a population of individual points and thus results in a more informed a posteriori decision on the tradeoff issues between the various objectives. This paper addresses the definition of the assembly components and their relationships (ECDP), the definition of the configuration design optimization method (CDOM), and shows the application of the CDOM to one academic and two engineering test cases.

Author(s):  
Pierre M. Grignon ◽  
Georges M. Fadel

Abstract This work presents a method (CDOM) for optimizing multiple system level assembly characteristics of complex mechanical assemblies by placement of their components. It addresses any component shape (including non-convex, hollow, sharp edges) connected together by functional constraints. This method finds multiple solutions to the Engineering Configuration Design Problem (ECDP) and proposes a simple cooperation scheme with the engineer using a Genetic Algorithm working on population of sets instead of population of individual points. In this paper four areas are addressed: • defining the assembly components and their relations (ECDP) • defining the Configuration Design Optimization Method (CDOM) • propose two strategies to improve the CDOM performance • show application of the CDOM to one academic and two engineering test cases


2005 ◽  
Vol 6 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Sudarsan Rachuri ◽  
Young-Hyun Han ◽  
Sebti Foufou ◽  
Shaw C. Feng ◽  
Utpal Roy ◽  
...  

The important issue of mechanical assemblies has been a subject of intense research over the past several years. Most electromechanical products are assemblies of several components, for various technical as well as economic reasons. This paper provides an object-oriented definition of an assembly model called the Open Assembly Model (OAM) and defines an extension to the NIST Core Product Model (NIST-CPM). The assembly model represents the function, form, and behavior of the assembly and defines both a system level conceptual model and associated hierarchical relationships. The model provides a way for tolerance representation and propagation, kinematics representation, and engineering analysis at the system level. The assembly model is open so as to enable plug-and-play with various applications, such as analysis (FEM, tolerance, assembly), process planning, and virtual assembly (using VR techniques). With the advent of the Internet more and more products are designed and manufactured globally in a distributed and collaborative environment. The class structure defined in OAM can be used by designers to collaborate in such an environment. The proposed model includes both assembly as a concept and assembly as a data structure. For the latter it uses STEP. The OAM together with CPM can be used to capture the assembly evolution from the conceptual to the detailed design stages. It is expected that the proposed OAM will enhance the assembly information content in the STEP standard. A case study example is discussed to explain the Usecase analysis of the assembly model.


Author(s):  
Michele Trancossi ◽  
Antonio Dumas ◽  
Mauro Madonia

It is possible to define a novel design method, which aims overcoming both traditional, the traditional Multidisciplinary Design Optimization, and to solve a fundamental issue relating to the actual formalization of the Constructal optimization method. It aims only to enhance and integrate the constructal design method and aims to produce designs, which could be, optimized both at system level and subsystem definition. This novel method is based on the second principle of thermodynamics and the constructal law. It aims to produce a design process based on two steps. The first step aims producing a theoretical design of a system to reach energetic and operative optimization. The second aims to optimize the subcomponents of the system according the bottom up approach defined by constructal design optimization. A third step relating to the readiness against technology analysis is necessary to develop an effective industrial design. This method has named Constructal Design for Efficiency. In this paper the authors, starting from the experience produced by the MAAT EU FP7, about the design of a cruiser-feeder and energy self sufficient airship for transport has produced the optimization of a medium altitude airship for transport, focused on the optimization of flying vehicle architecture to minimize by design the energy consumption during flight. The produced results allow defining a novel airship concept, which optimizes the airship shape to reach three fundamental energetic goals: energy consumption minimization; photovoltaic energy production maximization; definition of the conditions for energetically self-sufficient flight. The defined architecture can maximize the operative possibilities realizing an airship, which can ensure a point-to-point ground, based logistic models without any airport infrastructure with potential breakthrough impacts because of a better integration with any other terrestrial, maritime and aerial transport mode. Notwithstanding the use of hydrogen, it ensures an increased perception of safety by potential customers. It presents a safer ballooning architecture, without internal air ballonets, a cabin not directly attached to the bottom part of the balloon, which can be detached and piloted safely on the ground in case of serious accident during flight.


2015 ◽  
Vol 62 (8) ◽  
pp. 4702-4713 ◽  
Author(s):  
Gang Lei ◽  
Tianshi Wang ◽  
Jianguo Zhu ◽  
Youguang Guo ◽  
Shuhong Wang

2012 ◽  
Vol 490-495 ◽  
pp. 2515-2519
Author(s):  
Bi Qiang Yu ◽  
Xiao Qun Wang ◽  
Lin Hao Wang

In studying Multidisciplinary Object Compatibility Design Optimization method for non-hierarchic system, Simulated Annealing algorithm is introduced to establish system level model , and the basic ideas and working principle is given. In the optimization of system level, the coupling relationship between different subsystems is improved by state accepting function which is embedded in constraint. In this way, abnormal program termination and premature convergence will be avoided and ideal global optimal solution will be achieved effectually. Then the method is proved by used in the optimization design of pendulous micromechanical accelerometer


Author(s):  
Michael Nucci ◽  
Graeme Sabiston ◽  
Christopher Carrick ◽  
Il Yong Kim

This paper presents a method for a system level design optimization, using currently available commercial tools. A process outlining the optimization steps to be used was created based on performing topology optimization on important components and performing a conceptual topology optimization on the entire system. Using this process, a study was performed on a ceiling structure provided by an industry partner. From the design requirements, three primary areas were targeted for design optimization, the component level optimization of the cross beam component, the component level optimization of a roof attachment bracket, and the system level of the general roof structure. This study produced a design for the ceiling structure that reduced the total mass of the system by 34%, while also reducing the amount of total components in the system by 30%.


Author(s):  
Paul Chaisty ◽  
Nic Cheeseman ◽  
Timothy J. Power

This chapter summarizes the main parameters of coalitional presidentialism and the key concepts, definitions, explanatory frameworks, indicators, and propositions. It summarizes our understanding of coalitional presidentialism; the distinction between coalition formation and maintenance; the definition of coalitions; the multidimensional understanding of coalition management (the ‘presidential toolbox’); and an analytical framework that emphasizes the motivation of presidents to achieve cost minimization under constraints determined by system-level, coalition-level, and conjunctural factors. It also summarizes our main empirical findings: (1) the characteristics of presidential tools, (2) the substantive patterns of their deployment, (3) the factors that shape the costs of using these tools, (4) the actual (observed) costs of using them, and (5) the potential for imperfect substitutability of these tools. Finally, it concludes with some reflections on the current state of the research on comparative presidentialism.


Author(s):  
Myung-Jin Choi ◽  
Min-Geun Kim ◽  
Seonho Cho

We developed a shape-design optimization method for the thermo-elastoplasticity problems that are applicable to the welding or thermal deformation of hull structures. The point is to determine the shape-design parameters such that the deformed shape after welding fits very well to a desired design. The geometric parameters of curved surfaces are selected as the design parameters. The shell finite elements, forward finite difference sensitivity, modified method of feasible direction algorithm and a programming language ANSYS Parametric Design Language in the established code ANSYS are employed in the shape optimization. The objective function is the weighted summation of differences between the deformed and the target geometries. The proposed method is effective even though new design variables are added to the design space during the optimization process since the multiple steps of design optimization are used during the whole optimization process. To obtain the better optimal design, the weights are determined for the next design optimization, based on the previous optimal results. Numerical examples demonstrate that the localized severe deviations from the target design are effectively prevented in the optimal design.


2009 ◽  
Vol 23 (03) ◽  
pp. 477-480 ◽  
Author(s):  
ZHILI TANG

The Taguchi robust design concept is combined with the multi-objective deterministic optimization method to overcome single point design problems in Aerodynamics. Starting from a statistical definition of stability, the method finds, Nash equilibrium solutions for performance and its stability simultaneously.


Sign in / Sign up

Export Citation Format

Share Document