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Authors
Kumar, Swagat; Padhi, Radhakant; Behera, Laxmidhar

Digital Object Identifier (DOI)
10.3182/20080706-5-KR-1001.01487

Page Numbers:
8797-8802

Index Terms
Optimal control theory; Regulation; Optimization based controller synthesis

Abstract
An optimal control law for a general nonlinear system can be obtained by solving Hamilton-Jacobi-Bellman equation. However, it is difficult to obtain an analytical solution of this equation even for a moderately complex system. In this paper, we propose a continuoustime single network adaptive critic scheme for nonlinear control affine systems where the optimal cost-to-go function is approximated using a parametric positive semi-definite function. Unlike earlier approaches, a continuous-time weight update law is derived from the HJB equation. The stability of the system is analysed during the evolution of weights using Lyapunov theory. The effectiveness of the scheme is demonstrated through simulation examples.

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