Thus, the invention is best suited to {TAIL ~ robot welding} in order to improve {HEAD ~ productivity} 
Thus , the invention is best suited to { TAIL ~ robot welding } in order to improve { HEAD ~ productivity }
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD