Nonlinear H Control for Uncertain Flexible Joint Robots with Unscented Kalman Filter


Todays, use of combination of two or more methods was considered to control of systems. In this paper is
presented how to design of a nonlinear H∞ (NL-H∞) controller for flexible joint robot (FJR) based on bounded
UKF state estimator. The UKF has more advantages to standard EKF such as low bios and no need to
derivations. In this research, based on spong primary model for FJRs, same as rigid robots links position are
selected as differential equations variables. Then this model was reformed to NL H differential equations.
The results of simulations demonstrate that mixed of NL H controller and UKF estimator lead to
conventional properties such as stability and good tracking. Also, Simulation results show the efficiency and
superiority of the proposed method in compare with EKF.

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