The second part of the experiment m

The second part of the experiment mainly displays the
quadrocopter robustness to a short-term loss of video-camera data.
The quadrocopter is first put into autonomous hovering mode, in
the moments t1 = 51 s, t2 = 55 s and t3 = 78 s it is pushed
out of the reference position by hand. Although the video-camera
loses the target out of the view (illustrated by the red background
in Fig. 11), the quadrocopter returns to the reference position and
continues hovering.