The method further comprises measuring the first and second components based on {TAIL ~ the error signal} and {HEAD ~ the repeatable component} 
The method further comprises measuring the first and second components based on { TAIL ~ the error signal } and { HEAD ~ the repeatable component }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD