At present, robotic manipulators are commonly used in manufacturing industry. In many cases, their end-effectors are required to move from one place to the other and follow some desired trajectories. This paper develops a nonlinear backstepping control design scheme with velocity observers for the trajectory tracking control of robotic manipulators. In fact, most of robot manipulator controller...

This paper is about state estimation for nonlinear uncertain continuous-time systems in a bounded-error context. We introduce a method for designing a guaranteed interval observer which is based on (i) the application of Müller’s theorem for bracketing the solution of ordinary differential equations in a way which ensures the positivity of the observation error, (ii) the analysis of the monoton...

A dynamic neural network (DNN) based robust observer for uncertain nonlinear systems is developed. The observer structure consists of a DNN to estimate the system dynamics on-line, a dynamic filter to estimate the unmeasurable state and a sliding mode feedback term to account for modeling errors and exogenous disturbances. The observed states are proven to asymptotically converge to the system ...

A general class of MIMO nonlinear systems with unknown inputs is considered with a view to observer synthesis. The particularity of this class of systems lies in the fact that the expression of the outputs depends on the unknown inputs. Different situations are considered and in each case a nonlinear observer, synthesized under appropriate hypotheses, is proposed to jointly estimate all state v...

Perspective dynamical systems arise in machine vision, in which only perspective observation is available. This paper proposes and studies a Luenberger-type nonlinear observer for perspective time-invariant linear systems. Assuming a given perspective time-invariant linear system to be Lyapunov stable and to satisfy some sort of detectability condition, it is shown that the estimation error con...

I t is known that for affine nonlinear systems the drift-observability property (i. e. observability for zero input) is not sufficient to guarantee the existence of an asymptotic observer for any input. Many authors studied structura.l conditions that ensure uniform observability of nonlinear systems (i. e. observability for any input). Conditions are available that define classes of systems th...

The main objective of this work is to study the relationship between passivity and existence of UIO in the nonlinear case. This work is motivated by two facts: On the one side by the well-known relationship between passivity and robustness in control theory. On the other side the equivalence previously found by one of the authors in the linear (square) case between three concepts: existence of ...

Globally convergent observers are designed for a class of systems with monotonic nonlinearities. The approach is to represent the observer error system as the feedback interconnection of a linear system and a time-varying multivariable sector nonlinearity. Using LMI software, observer gain matrices are computed to satisfy the circle criterion and, hence, to drive the observer error to zero. In ...

This paper is concerned with stability analysis problem of nonlinear observer design for a class of multilink flexible manipulators (MLFMs). Specifically, the dynamics of the MLFM is modeled by the use of a Lagrangian approach. In a unified algebraic Riccati matrix equality (ARME) framework, one corresponding error-state system is proven to be asymptotic stable in the mean square (ASMS) for a n...

A high gain observer is proposed for a class of multi-output nonlinear systems with unknown inputs in order to simultaneously estimate the whole state as well as the unknown inputs. The gain of this observer does not require the resolution of any dynamical system and is explicitly given. Moreover, its tuning is reduced to the choice of two real numbers. The performances of the proposed observer...