Coupling and Controllability in Optimal Design and Control.

Coupled Design and Control;Co-design;Controllability;Mechanical Engineering;Engineering;Mechanical Engineering

Peters, Diane L.Sun, Jing ;

University of Michigan

关键词: Coupled Design and Control;    Co-design;    Controllability;    Mechanical Engineering;    Engineering;    Mechanical Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/75943/dlpeters_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

So-called ;;smart’ products have the potential to improve life dramatically from the smallestscale, such as biological micro-electrical mechanical sensors for health monitoring, to thelargest scale, such as electrical grids and transportation networks. All of these technologiesrequire the design of both an artifact and a controller, and one can assert that optimalartifact and controller designs are required in order to realize their full benefit. The problemof combined design of artifact and controller is termed co-design. Coupling between theartifact and controller design problems has been demonstrated to be critical in the co-designof many such systems. It is necessary, then, to be able to identify coupling in these systemsand to choose an optimization method that can optimize a coupled system particularly withrespect to its controllability. This is the focus of the present dissertation.Relationships are derived between known coupling metrics and the controllability Grammianmatrix of the system. These relationships represent a first a priori determination ofcoupling, namely, assessment of coupling between design and control decisions prior tosystem optimization. Previous work had focused on coupling metrics that require knowledgeof the system optimum to compute coupling strength and choose an appropriate systemdesign method. This dissertation introduces the Control Proxy Function (CPF) concept.A CPF is defined as a measure of the system’s ease of control. CPFs are derived forcertain classes of problems, and examples are presented. For a co-design problem with aderived CPF, a sequential system design process can be effected, with the CPF augmentingthe original artifact objective function. The optimal design and control problems canthen be solved in sequence, while preserving system optimality. Conditions are derivedunder which the method is effective, and guidelines for the choice of a CPF are provided.The method is demonstrated in the co-design of a MEMS actuator. Results show that thismethod can be used to co-design systems effectively, allowing a designer to realize systemoptimal, or near-optimal, results with the simplicity of a sequential design process.