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accelerationsensor-absolute

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accelerationsensor-absolute

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Library

Iconic Diagrams\Mechanical\Rotation\Sensors

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Rotation), Block Diagrams.

Description

This model describes an acceleration sensor which derives an angular acceleration output out of a port angular velocity by differentiation. Differentiation is performed by a state variable filter:

DifferentiateSVF

The S-domain function of this filter is equal to:

DifferentiateSVFequation

where f is the cut-off frequency. For very high values of f, the output becomes the pure derivative of the input. High values of f, however, increase simulations times. A good trade-off is a starting value of 1e5.

 

The equations of this model are:

 

alpha = d( p.omega)/dt;

p.T = indifferent;

Interface

Ports

Description

p

Rotation port p.

Causality

 

fixed force out

 

Output

 

alpha

Absolute angular acceleration [rad/s2]

Parameters

 

f

alpha_initial

Cut-off frequency of the differentiation [Hz].

Initial angular acceleration [m/s].