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Translational Friction

Purpose

Ideal translational stick/slip friction

Library

Mechanical / Translational / Components

Description

pict

The Translational Friction models any combination of static, Coulomb and viscous friction between two flanges in a translational system. While the component is stuck, it exerts whatever force is necessary in order to maintain zero relative speed between the flanges, up to the limit of the breakaway force Fbrk  . When the breakaway force is exceeded, the flanges begin sliding against each other, and the component exerts a force that consists of the Coulomb friction force FC   and a speed-dependent viscous friction force cv ⋅v  .

The figure below shows the speed/force characteristic and the state chart of the component. Note that the friction force is opposed to the movement, hence the negative sign.

pict

Parameters

Breakaway friction force
The maximum magnitude of the stiction force Fbrk  , in Netwon. Must be greater than or equal to zero.
Coulomb friction force
The magnitude of the (constant) Coulomb friction force FC  , in Netwon. Must be greater than or equal to zero and less than or equal to the breakaway friction force.
Viscous friction coefficient
The proportionality coefficient cv   that determines the speed dependent viscous friction force, in Ns
m  .

Probe Signals

Force
The transmitted force F   flowing from the unmarked to the marked flange, in Newton (N).
Speed
The speed v   of the marked flange with respect to the unmarked flange, in m
s-  .
State
The internal state of the component: -1 sliding backward, 0 stuck, +1 sliding forward.