to the long-lived island (Fig. \[fig:no\_control\], panels (a) and (b)). Then it moves away, but still along the filaments $250\lesssim t\lesssim 450,$ Fig. \[fig:control\] left column (panels a, c, and e). Finally the red cross lies in the white region which corresponds to an extremely fast escape, see Fig. \[fig:control\] (g).

The RT escapes without any intervention after $t\approx$ 450 days, which is on the same magnitude as the average lifetime ($\tau$) introduced in Section 3.3. Having constructed all the ICMs until the escape (Fig. \[fig:no\_control\] and Fig. \[fig:control\] left column), we can formulate the basic objective of the control procedure. That is, *the RT should be shifted from filaments to a long-lived island with the lowest possible energy consumption.*

![image](fig8a){width="84mm"} ![image](fig8b){width="84mm"}\
![image](fig8c){width="84mm"} ![image](fig8d){width="84mm"}

There are two essential questions arising: 1. How to do this? 2. When to do this?

We start with the answer to the second question. Obviously, the control must start before the RT leaves the filamentary structure. A good indicator of this is the average lifetime of chaotic behaviour, $\tau\approx$ 200 days. Let us consider the ICM corresponding to instance $t=$244.95, which is the 10th ICM after $t$=0, Fig. \[fig:no\_control\] (f). We might want to start 