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Title: Robust and finite-time stable model-free control for second order systems without velocity measurements
This article presents a framework for model-free control design for mechanical systems without velocity measurements and with an unknown dynamics, considered as a bounded disturbance input. The system states consist of zeroth-order (e.g position) and first-order (e.g velocity) vectors, but only the zeroth-order states are the measured outputs. This model-free control framework is based on a first-order signal differentiator and a finite-time stable extended state observer that simultaneously estimates the states and the bounded disturbance input in real time with guaranteed bounds on accuracy of the estimates. The estimates provided by this observer are used to track a desired output trajectory and compensate the disturbance in real time. Overall nonlinear stability and robustness of the observer is shown theoretically and verified through numerical simulations. The proposed method can be applied to second-order systems and their teams, like mobile robots, unmanned aerial vehicles, unmanned (under)water vehicles and space vehicles.  more » « less
Award ID(s):
2132799 2343062
PAR ID:
10657088
Author(s) / Creator(s):
 ;  
Publisher / Repository:
IEEE
Date Published:
Page Range / eLocation ID:
1905 to 1910
Subject(s) / Keyword(s):
Model-free control, Hölder-continuous, finite-time stable
Format(s):
Medium: X
Location:
Milan, Italy
Sponsoring Org:
National Science Foundation
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