UNKNOWN INPUT OBSERVER FOR STATE AFFINE SYSTEMS - A GEOMETRIC EXISTENCE CONDITION

The problem of designing of an unknown input observer for linear systenis is widely studied in the literature. Using the geometric approach, an irrtririsic characterization permitting to design such an observer is stated in [l], I41 and [ZJ. In this paper an unknown input observer design for a class of state affine systenis is considered. As in [2], a geometric sufficient condition is given in order to design such an unkriown input observer.