A friction testing machine and method for measuring {HEAD ~ friction characteristics} between a test sample and {TAIL ~ a friction surface} 
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A friction testing machine and method for measuring { HEAD ~ friction characteristics } between a test sample and { TAIL ~ a friction surface }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL