Minimal root sensitivity in linear systems Academic Article uri icon


  • Nominal performance, root sensitivity, and stability are important control design considerations. This paper deals only with the first two of these concerns. A lower bound is derived for root sensitivity and necessary and sufficient conditions are given to achieve this minimum. This is the main result of the paper. In addition, an optimal output feedback control problem is discussed which penalizes an index related to root sensitivity. Two hazards are clarified concerning root sensitivity designs. First, we illustrate that root sensitivity has nothing to do with stability. Second, we show that normality of the plant matrix is the necessary and sufficient condition for minimal root sensitivity, but that normality measures can be convex even when root sensitivity measures are not. Hence, the optimization problems are quite different, and normality objectives cannot always be substituted for root sensitivity objectives. American Institute of Aeronautics and Astronautics Inc., 1983.

published proceedings

  • Journal of Guidance Control and Dynamics

author list (cited authors)

  • Skelton, R. E., & Wagie, D. A.

citation count

  • 34

complete list of authors

  • Skelton, RE||Wagie, DA

publication date

  • September 1984