Conclusions
An approach for combined control-structure optimization keyed to enhancing early design trade-offs has been outlined and illustrated by numerical examples. The approach employs a homotopic strategy and appears to be effective for generating families of designs that can be used in these early trade studies.
Analytical results were obtained for classes of structure/control objectives with LQG and LQR costs. For these, we have demonstrated that global optima can be computed for small values of the homotopy parameter. Conditions for local optima along the homotopy path were also given. Details of three numerical examples employing the LQR control cost were given showing variations of the optimal design variables along the homotopy path. The results of the second example suggest that introducing a second homotopy parameter relating the two parts of the control index in the LQG/LQR formulation might serve to enlarge the family of Pareto optima, but its effect on modifying the optimal structural shapes may be analogous to the original parameter λ.
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Communicated by S. N. Atluri, June 7, 1990
Part of this work was performed while the author was visiting the University of Southern California
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Milman, M., Salama, M., Scheid, R.E. et al. Combined control-structural optimization. Computational Mechanics 8, 1–18 (1991). https://doi.org/10.1007/BF00370544
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DOI: https://doi.org/10.1007/BF00370544