A drive circuit selectively applies current to each electromagnet to effect {HEAD ~ rotational force} on {TAIL ~ the rotor poles} 
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A drive circuit selectively applies current to each electromagnet to effect { HEAD ~ rotational force } on { TAIL ~ the rotor poles }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL