AN ALGORITHM FOR SYSTEM IMMERSION INTO NONLINEAR OBSERVER FORM: FORCED SYSTEM

Abstract The class of nonlinear system that can be put into nonlinear observer form (linear system with output injection) can be broadened if we employ the system immersion. We provide an algorithm with which one can check whether a forced system with relative degree r can be transformed into nonlinear observer form or not. The proposed algorithm is an extension of the previous result and does not require the relative degree 1 assumption. In addition, it is seen that, the immersibility can always be checked via algebraic computations except one special case when the relative degree equals to the system dimension (in the case, only one first order differential equation appears in the algorithm).