Elliptically excited pendulum (EEP) is a mathematical pendulum in the vertical plane whose pivot oscillates not only vertically but also horizontally with π/2 phase shift, so that the pivot has elliptical trajectory, see Fig. 1. EEP is a natural generalization of pendulum with vertically vibrating pivot that is one of the most studied classical systems with parametric excitation, so it is often referred to simply as parametric pendulum, see for example [1–4] and references therein.