Nonlinear map inversion via state observers
Circuits, Systems, and Signal Processing
Nonlinear control design: geometric, adaptive and robust
Nonlinear control design: geometric, adaptive and robust
Adaptive control of continuous time systems with convex/concave parametrization
Automatica (Journal of IFAC)
Nonlinear and Adaptive Control Design
Nonlinear and Adaptive Control Design
Adaptation Algorithms in Finite form for Nonlinear Dynamic Objects
Automation and Remote Control
Automatica (Journal of IFAC)
Brief Growth rate conditions for uniform asymptotic stability of cascaded time-varying systems
Automatica (Journal of IFAC)
Adaptive observers and parameter estimation for a class of systems nonlinear in the parameters
Automatica (Journal of IFAC)
| Hi-index | 22.15 |
We consider a class of systems influenced by perturbations that are nonlinearly parameterized by unknown constant parameters, and develop a method for estimating the unknown parameters. The method applies to systems where the states are available for measurement, and perturbations with the property that an exponentially stable estimate of the unknown parameters can be obtained if the whole perturbation is known. The main contribution is to introduce a conceptually simple, modular design that gives freedom to the designer in accomplishing the main task, which is to construct an update law to asymptotically invert a nonlinear equation. Compensation for the perturbations in the system equations is considered for a class of systems with uniformly globally bounded solutions, for which the origin is uniformly globally asymptotically stable when no perturbations are present. We also consider the case when the parameters can only be estimated when the controlled state is bounded away from the origin, and show that we may still be able to achieve convergence of the controlled state. We illustrate the method through examples, and apply it to the problem of downhole pressure estimation during oil well drilling.