Nonlinear state observers by gradient descent method

Abstract

This paper concerns with a new nonlinear state observer of deterministic general nonlinear systems; which is designed based on the gradient descent method for decreasing squared estimation errors. The convergence of the proposed observer is proved by using the Bihari type inequality which generalizes the Gronwall inequality. We confirm from various simulations that our method works very well as a nonlinear state observer with superior convergence properties.