Abstract
Time delayed feedback control is one of practical methods for stabilizing unstable periodic orbits embedded in chaotic attractors. This control method has an open problem of estimating domain of attraction towards stabilized orbits in function space. In this paper, domain of attraction in two types of Duffing system under the control method is numerically discussed. The disturbance to initial conditions towards stabilized orbits shows the domain of attraction possibly has self-similar structures in their boundaries.