at least two sensor means each having a detection area partly overlapping each other and generating an output in {HEAD ~ accordance} with {TAIL ~ a detected quantity} 
with
at least two sensor means each having a detection area partly overlapping each other and generating an output in { HEAD ~ accordance } with { TAIL ~ a detected quantity }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL