A device to detect the location of {HEAD ~ a plurality} of {TAIL ~ magnets} uses a plurality of magnetic sensors, having sensor elements arranged in a known fashion 
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A device to detect the location of { HEAD ~ a plurality } of { TAIL ~ magnets } uses a plurality of magnetic sensors , having sensor elements arranged in a known fashion
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH