The semi-analytical method is conveniently used to obtain design sensi
tivities. However, it may have serious accuracy problems in shape desi
gn. In this study, an improved semianalytical method is presented for
the accurate computation of shape design sensitivities. The method is
based on approximating the flexibility matrix by means of von Neumann
series. In numerical examples, two cases for which the standard semian
alytical method fails are considered. It is demonstrated that the sens
itivities can be obtained very accurately by the improved method propo
sed.