We derive sufficient conditions for the solvability of the state estimation problem for a class of nonlinear control time-varying systems which includes those, whose dynamics have triangular structure. The state estimation is exhibited by means of a sequence of functionals approximating the unknown state of the system on a given bounded time interval. More assumptions guarantee solvability of the state estimation problem by means of a hybrid observer.
@article{arxiv.1803.08386,
title = {Observability and State Estimation for a Class of Nonlinear Systems},
author = {John Tsinias and Constantinos Kitsos},
journal= {arXiv preprint arXiv:1803.08386},
year = {2018}
}