Library.Iconic_Diagrams.Mechanical.Translation.Components.FrictionSimple-Relative

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Library.Iconic_Diagrams.Mechanical.Translation.Components.FrictionSimple-Relative

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Iconic Diagrams\Mechanical\Translation\Components

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Translation).

Implementations

C

V

CV

SCVS

LuGre

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Translation).

Introduction

These models represents friction with the fixed world. The amount of friction does not depend on the normal force but determined by parameters directly. The models have only one initial port p defined. The port p of the friction models have separate high and low terminals. The equations are:

 

p.F = p_high.F = p_low.F

p.v = p_high.v - p_low.v

 

Description - C

This model represents friction with the fixed world described as coulomb friction:

 

p.F = Fc*tanh(slope*p.v);

 

Fc: the coulomb friction

slope: the steepness of the coulomb and static friction curve.

 

CoulombFriction

 

Interface - C

Ports

Description

p[any]

Any number of connections can be made (Translation).

Causality

 

Fixed force out

 

Parameters

 

Fc

slope

Coulomb friction [N]

Steepness of Coulomb friction curve [s/m]

Description - V

This model represents friction with the fixed world described as viscous friction:

 

p.F = d*p.v;

 

d: the viscous friction or damping

 

ViscousFriction

 

Interface - V

Ports

Description

p[any]

Any number of connections can be made (Translation).

Causality

 

Fixed force out

 

Parameters

 

d

Viscous friction or damping [N.s/m]

 

Description - CV

This model represents friction with the fixed world described as coulomb plus viscous friction:

 

p.F = Fc*tanh( slope*p.v ) + d*p.v;

 

d: the viscous friction or damping

Fc: the coulomb friction

slope: the steepness of the coulomb and static friction curve.

 

CoulombViscousFriction

Interface - CV

Ports

Description

p[any]

Any number of connections can be made (Translation)

Causality

 

Fixed force out

 

Parameters

 

Fc

d

slope

Coulomb friction [N]

Viscous friction or damping [N.s/m]

Steepness of Coulomb friction curve [s/m]

Description - SCVS

This model represents friction with the fixed world described as static plus coulomb plus viscous plus Stribeck friction:

 

p.F = (( Fc + (Fst*abs(tanh( slope*p.v )) - Fc) * exp( -((p.v / v_st)^2 )) ) *  sign(p.v) + d * p.v);

 

Fst: the static friction

d: the viscous friction or damping

Fc: the coulomb friction

slope: the steepness of the coulomb and static friction curve.

v_st: the characteristic Stribeck velocity.

 

StaticCoulombViscousFriction

 

Interface - SCVS

Ports

Description

p[any]

Any number of connections can be made (Translation).

Causality

 

Fixed force out

 

Parameters

 

Fc

Fst

d

v_st

slope

Coulomb friction [N]

Static friction [N]

Viscous friction or damping [N.s/m]

Characteristic Stribeck velocity [m/s]

Steepness of Coulomb friction curve [s/m]

Description - LuGre

This model represents friction with the fixed world described by the LuGre friction model:

 

p.F = f_lg(p.v);

 

f_lg: the LuGre friction model

Interface - LuGre

Ports

Description

p[any]

Any number of connections can be made (Translation).

Causality

 

Fixed force out

 

Parameters

 

Fc

Fst

d

v_st

k

Coulomb friction [N]

Static friction [N]

Viscous friction or damping [N.s/m]

Characteristic Stribeck velocity [m/s]

Stiffness at zero speed [N/m]