A new nonlinear disturbance observer (NDO) for robotic manipulators is derived in this paper. The global exponential stability of the proposed disturbance observer (DO) is guaranteed by selecting design parameters, which depend on the maximum velocity and physical parameters of robotic manipulators. This new observer overcomes the disadvantages of existing DO’s, which are designed or analyzed b...

Abstract: In order to solve chattering problem of conventional sliding mode observer (SMO), this paper proposes a exponential reaching law sliding mode observer (ERL-SMO) for a permanent magnet synchronous motor (PMSM) which substitutes exponential reaching law for constant reaching law. The ERL-SMO estimates the rotor position and the angular velocity from the back electromotive force (EMF) ba...

In the control systems literature, it is well known that a separation principle holds locally for nonlinear control systems, when exponential feedback stabilizers and exponential observers are used. In this paper, we present a counterexample to show that the global separation principle need not hold for nonlinear control systems. Our example demonstrates that global stability might be lost when...

A convergence analysis of the modified unscented Kalman filter (UKF), used as an observer for a class nonlinear deterministic continuous time systems, is presented. Under certain conditions, extended (EKF) exponential non-linear i.e., dynamics estimation error exponentially stable. It shown that unlike EKF, UKF not converging observer. modification – proposed, which better candidate This paper ...

This thesis develops a nonlinear observer for the problem of pose estimation; that is, the determination of the position and attitude of a rigid body from sensor measurements. The observer is derived on the Special Euclidean group, SE (3), and exploits the natural Lie groups geometry of the space in the structure of the observer. The observer uses body fixed frame measurements of known landmark...

This paper is concerned with the observer design for one-dimensional linear parabolic partial differential equations whose output is a weighted spatial average of the state over the entire spatial domain. We focus on the backstepping approach, which provides a systematic procedure to design an observer gain for systems with boundary measurement. If the output is not a boundary value of the stat...

The problem of state reconstruction from input and output measurements for nonlinear time delay systems is studied in this paper and a state observer is proposed that is easy to implement and, under suitable assumptions on the system and on the input function, gives exponential observation error decay. The proposed observer is itself a delay system and can be classi ̄ed as an identity observer, ...

Aimed at the problems of system chattering and large observation errors in sensorless control a permanent magnet synchronous motor (PMSM) based on traditional sliding mode observer (SMO), combined reaching law algorithm exponential arcsine saturation function is proposed to improve observer. An appropriate positive real number taken compared with product controller gain stator current error jud...