a) providing {HEAD ~ a controller} operatively connected to {TAIL ~ each} of the independently driven nip rollers 
operatively connected to
a ) providing { HEAD ~ a controller } operatively connected to { TAIL ~ each } of the independently driven nip rollers
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH