Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
718470 | IFAC Proceedings Volumes | 2009 | 6 Pages |
This paper is concerned with the classification of sensors with respect to their importance for observability preservation under sensor failure. We consider linear observable systems and we wonder if a given system remains observable in case of sensor failure. In a previous work, the critical sensors, called essential, which failure leads to observability loss have been defined, as well as the useless ones, which may fail without impacting system observability. The main contribution of this paper is to provide with a refined classification of sensors for observability. For this purpose we define for each sensor a criticity degree related with its importance for observability preservation in case of sensor failure. The larger the criticity degree is, the worst for observability preservation in case of failure of this sensor. We use a network which represents all the possible situations in case of sensor failure, and we will exhibit a reduced network which captures all the relevant information. On this reduced network, we will easily associate with each sensor a quantitative measure of the seriousness of its possible failure.