This component models a brake component, where frictional force is acting between the housing and a flange, and a controlled normal force presses the flange to the housing to increase friction. The normal force, , must be provided as an input signal, , in a normalized form

(0 ≤  ≤ 1), fn = * 

where  is provided as a parameter.

Friction in the brake is modeled in the following way: when the absolute velocity, , is not zero, the friction force is a function of the velocity-dependent friction coefficient, , of the normal force, fn, and of a geometry constant, , which takes into account the geometry of the device and the assumptions on the friction distributions

The positive part of the friction characteristic, , , is defined by the table, , where the first column is v, and the second column is . Only linear interpolation is supported.

When the absolute velocity is zero, the absolute position remains constant. In this phase, the friction force is calculated from a force balance because the absolute acceleration must be zero. The elements begin to slide when the friction force exceeds a threshold value called the maximum static friction force (that is, ). This value is computed by

Two flanges,  and , are provided for convenience. They are located at the same position, so are essentially identical.

1-D Mechanical Overview

The components described in this topic are from the Modelica Standard Library. To view the original documentation, which includes author and copyright information, click here.