A Workshop will be organized on October 20-21, 2025.
High Gain Observer Design: Towards an Engineering System Approach M. Farza, H. Hammouri and M. Msaad
Prof. M. Farza is from LIS (UR 7478, Unicaen, ENSICAEN), Caen, France Prof. H. Hammouri is from LAGEP, Claude Bernard University - Lyon 1, UMR CNRS 5007, Lyon, France Prof. M. Msaad is from LIS (UR 7478, Unicaen, ENSICAEN), Caen, France
The two last decades have witnessed an increasing interest in high gain observer design to address the challenging problems of state reconstruction for uniformly as well as non uniformly observable nonlinear systems. The main motivation of this workshop is to provide a comprehensive overview on the available fundamental results dealing with high gain observer with a particular emphasis on recent probing achievements from an engineering system point of view. The basic stability and observability concepts are first recalled together with mathematical preliminaries that have been commonly used in advanced designs. Then, the Standard High Gain Observer (SHGO) design is gradually detailed and its main limitations are emphasized, i.e. its sensitivity to high frequency signals and the peaking phenomenon that occurs during its transient behavior. A redesigned version that allows to alleviate the sensitivity of SHGO with respect to those unavoidable measurement noise is then introduced. The resulting observer is referred to as a filtered high gain observer (FHGO) and shares the same structure of its underlying SHGO while inheriting the peaking phenomenon. In order to cope with this problem, the linear corrective term involved in the FHGO is substituted by appropriate nested saturation functions leading thereby to a saturated high gain observer (SATFHGO). The main properties of the SHGO as well as those of the FHGO and SATFHGO shall be illustrared through supervised Lab works under matlab environments.
