A new method for simultaneous optimum design of structural and control systems

Abstract

An optimization method is proposed for the simultaneous design of structural and control systems using the equivalent static loads. The two structural and control systems are not completely independent and hence must be considered in a unified fashion. Furthermore, the integrated system should be designed to exhibit a good performance in the time domain. The analysis of the integrated system should be conducted for the transient-state in a dynamic manner. The constraints for structural and control systems are defined in the time domain as well. Therefore, a small scale structural analysis problem may easily become a large scale optimization problem. A new equivalent static loads (ESLs) method, which deals with the structural design variables as well as the control design variables, is proposed to solve large scale problems. A finite element dynamic equation is defined with control forces and a dynamic response optimization problem is formulated. Linear static response optimization is carried out with the ESLs. The control forces for the linear static response optimization are considered as design variables. Shape variables are utilized to handle the design variables for the control forces. Several test problems are solved to validate the proposed method. (C) 2015 Elsevier Ltd. All rights reserved.