Determination of the set of observation programs guaranteeing observability of a nonlinear system (Q1285438)

Nonlinear, finite-dimensional, stationary dynamical systems are considered. The fundamental definitions of observability for nonlinear dynamical systems are presented. Next, using algebraic methods, sufficient conditions for different types of observability are formulated and proved. Moreover, simple illustrative examples are given. Several remarks and comments on nonlinear observability problems are presented. It should be pointed out that the results given in the paper make use of the formula for inversion of the output of a nonlinear control system. Finally, it should be stressed that similar nonlinear observability problems have been considered in the paper by \textit{D. Aeyels} [SIAM J. Control Optimization 19, 595-603 (1981; Zbl 0474.93016)].