modelPartialFrictionWithStop

Base model of Coulomb friction elements with stop

Extends from PartialRigid (Rigid connection of two translational 1D flanges).

Information

Basic model for Coulomb friction that models the stuck phase in a reliable way.
Additionally, a left and right stop are handled.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.PositionsmaxRight stop for (right end of) sliding mass
Modelica.Units.SI.PositionsminLeft stop for (left end of) sliding mass
SI.LengthL (from PartialRigid)Length of component, from left flange to right flange (= flange_b.s - flange_a.s)
IntegerUnknown3Value of mode is not known
IntegerFree2Element is not active
IntegerForward1v_rel > 0 (forward sliding)
IntegerStuck0v_rel = 0 (forward sliding, locked or backward sliding)
IntegerBackward-1v_rel < 0 (backward sliding)
Advanced
Modelica.Units.SI.Velocityv_small1e-3Relative velocity near to zero (see model info text)

Connectors

TypeNameDefaultDescription
Flange_aflange_a (from PartialTwoFlanges)(left) driving flange (flange axis directed into cut plane, e. g. from left to right)
Flange_bflange_b (from PartialTwoFlanges)(right) driven flange (flange axis directed out of cut plane)

Components

TypeNameDefaultDescription
Modelica.Units.SI.Velocityv_relfricRelative velocity between frictional surfaces
Modelica.Units.SI.Accelerationa_relfricRelative acceleration between frictional surfaces
Modelica.Units.SI.ForcefFriction force (positive, if directed in opposite direction of v_rel)
Modelica.Units.SI.Forcef0Friction force for v=0 and forward sliding
Modelica.Units.SI.Forcef0_maxMaximum friction force for v=0 and locked
Booleanfree= true, if frictional element is not active
RealsaPath parameter of friction characteristic f = f(a_relfric)
BooleanstartForward= true, if v_rel=0 and start of forward sliding or v_rel > v_small
BooleanstartBackward= true, if v_rel=0 and start of backward sliding or v_rel < -v_small
Booleanlocked= true, if v_rel=0 and not sliding
SI.Positions (from PartialRigid)Absolute position of center of component (s = flange_a.s + L/2 = flange_b.s - L/2)
IntegermodeMode of friction (-1: backward sliding, 0: stuck, 1: forward sliding, 2: inactive, 3: unknown)