Sliding mode cubic observer for state estimation of linear and Lipschitz nonlinear systems

This paper proposes a composite state observer structure that combines the sliding mode and cubic observers for state estimation of linear time-invariant and nonlinear Lipschitz systems. The proposed observer generalises the aforementioned ones and can be reduced by the proper assignment of parameters. Convergence criteria and performance advantages are given for the proposed observer structure. The paper also provides a simple structural parameter selection framework for the design of the sliding mode and sliding mode cubic observers. Simulation examples show the superiority of the proposed observer to the existing ones.