Friction Modelling ofServomechanical Systems withDual-relay Feedback

Inthis paper, anapproach toidentify amodelfor servo-mechanical systems using dual-relay feedback ispresented. Themodelwill capture thelinear dynamics ofthesystem aswell asthefrictional forces affecting system, through acomprehensive friction modelwhichincludes static friction, Coulombfriction, viscous friction andtheboundary lubrication velocity. This friction modelisabletoadequately describe thefriction property whentheservosystem runsunderbothlowandhighvelocity modes. Properties oftheoscillations induced underthedual-relay will bepresented, basedonwhich, insights fortheselection ofthe relay parameters canbedrawn.A systematic setofprocedures toderive alltheparameters ofthemodelwillbefurnished. Results fromasimulation studywillbepresented toillustrate thepractical appeal oftheproposed method.