The servo control energizes {TAIL ~ the linear electromagnetic actuator} with a current which always has the proper polarity and value to compensate for {HEAD ~ losses} 
The servo control energizes { TAIL ~ the linear electromagnetic actuator } with a current which always has the proper polarity and value to compensate for { HEAD ~ losses }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD