moving the apparatus and {TAIL ~ user} along {HEAD ~ an indirect path} away from a fixed starting point 
moving the apparatus and { TAIL ~ user } along { HEAD ~ an indirect path } away from a fixed starting point
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH