In {HEAD ~ a system} for locating {TAIL ~ a moving object} with respect to an axis comprising: 
In { HEAD ~ a system } for locating { TAIL ~ a moving object } with respect to an axis comprising :
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH