Discussion on “Semi-Implicit Euler Digital Implementation of Conditioned Super-Twisting Algorithm With Actuation Saturation”

Exact state estimation for linear systems with unknown inputs based on hierarchical super-twisting algorithm

A robust hierarchical observer is designed for linear time invariant systems with unknown bounded inputs under conditions of strong observability, providing exact state estimation. The main condition for designing the state estimator is the, so-called, strong observability condition. The supertwisting (secondorder sliding mode) algorithm is used in each step of the hierarchy; the continuity of ...

Semi-implicit Euler Scheme for Generalized Newtonian Fluids

Rheological behavior of certain non–Newtonian fluids in engineering sciences is often modeled by power law ansatzes with p ≤ 2. So far, existing numerical analysis for local strong solutions study a fully implicit time discretization and find only restricted ranges of admissible p’s for corresponding error estimates [9]; different nonlinear stabilization strategies which allow a corresponding e...

A note on convergence of semi-implicit Euler methods for stochastic pantograph equations

Super twisting algorithm-based step-by-step sliding mode observers for nonlinear systems with unknown inputs

This paper highlights the interest of step-by-step higher order sliding mode observers for MIMO nonlinear systems with unknown inputs. A structural matching condition, stating on the possibility to design such observers and to reconstruct the unknown inputs, is derived. A finite time sliding mode observer, based on the hierarchical use of the super twisting algorithm, is developed. Then, it is ...

A multivariable super-twisting sliding mode approach

This communique proposes a multivariable super-twisting sliding mode structure which represents an extension of the wellknown single input case. A Lyapunov approach is used to show finite time stability for the system in the presence of a class of uncertainty. This structure is used to create a sliding mode observer to detect and isolate faults for a satellite system.