Stable discrete observation programs in analytic dynamical systems (Q1972519)

Nonlinear, finite-dimensional, time-varying dynamical systems are considered. It is assumed that the output algebraic equation is also nonlinear. The main purpose of the paper is to present the problem of finding the discrete observation programs providing unique reconstruction of the motion. Moreover, this program should be stable under small perturbations. Using algebraic methods and observability conditions, the construction of the observation program is proposed and discussed. Several remarks and comments on nonlinear observability problems are also presented. Similar problems have been recently considered in [\textit{K. E. Starkov}, Autom. Remote Control 56, No. 7, Pt. 1, 933-941 (1995); translation from Avtom. Telemekh. 1995, No. 7, 32-42 (1995; Zbl 0927.93019)].