A robust invariant observer design for invariant vector field system

This paper proposes a robust invariant observer design frame for the invariant vector field system. Based on the theorem of he group transformation, the original invariant observer is simplified and an invariant integral item is incorporated into the observer to decrease the uncertainty in the dynamics equation of the observer. Furthermore, a gam setting method is constructed to guarantee the tracking error the global convergence. The numerical example is provided to illustrate the efficiency of the observer.