Figure 5

Period-one orbit with a segment of sliding motion established by \(\bar{\xi}\in \mathcal {M}^{0}_{-}\). (a), (b) If \(\bar{\xi}_{4}=0\), \(\beta^{-}=2\). (c) If \(\bar{\xi}_{4}\neq0\), \(\beta^{-}=1\), the flow has no intersection with \(\mathcal {M}^{c}\), which is called one-zonal orbit