The s shaped movement of the rear pane 3 means that the gap 16 tapers in the z lifting direction in such a way that it is not possible to free the object 18 by {TAIL ~ movement} in a direction in {HEAD ~ the xz plane} 
The s shaped movement of the rear pane 3 means that the gap 16 tapers in the z lifting direction in such a way that it is not possible to free the object 18 by { TAIL ~ movement } in a direction in { HEAD ~ the xz plane }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD