# Robust exact differentiators with predefined convergence time

Title | Robust exact differentiators with predefined convergence time |

Publication Type | Journal Article |

Year of Publication | 2021 |

Authors | Seeber R, Haimovich H, Horn M, Fridman LM, De Battista H |

Journal | Automatica |

Volume | 134 |

Pagination | 109858 |

ISSN | 0005-1098 |

Keywords | Disturbance rejection, Finite-time convergence, Fixed-time convergence, Sliding modes, super-twisting algorithm |

Abstract | The problem of exactly differentiating a signal with bounded second derivative is considered. A class of differentiators is proposed, which converge to the derivative of such a signal within a fixed, i.e., a finite and uniformly bounded convergence time. A tuning procedure is derived that allows to assign an arbitrary, predefined upper bound for this convergence time. It is furthermore shown that this bound can be made arbitrarily tight by appropriate tuning. The usefulness of the procedure is demonstrated by applying it to the well-known uniform robust exact differentiator, which is included in the considered class of differentiators as a special case. |

URL | https://www.sciencedirect.com/science/article/pii/S0005109821003782 |

DOI | 10.1016/j.automatica.2021.109858 |

Research Line:

TeorĂa de Control

Control theory

High order sliding mode algorithms

Algoritmos por modo deslizante de orden superior