A new state observer for perspective systems

In this note, we consider the problem of estimating the state of a class of perspective systems. The problem can be converted into the observation of a dynamical system with nonlinearities. A new discontinuous state observer, which is motivated by the sliding mode control method and adaptive techniques, is proposed for the obtained dynamical system. The assumptions are reasonable, and the convergence conditions are intuitive and have apparently physical interpretations. The attraction of the new method is that the algorithm is very simple and easy to be implemented, and it is robust to measurement noises. Further, minor a priori knowledge of the system is required in the new formulation. Simulation results show the superiority of the new method to the traditional ones.