positionactuator

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positionactuator

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Library

Iconic Diagrams\Mechanical\Translation\Actuators

Use

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

Description

This model represents an ideal actuator. A position input signal is differentiated by a state variable filter to a velocity at the translation port. The actuator is mounted to the fixed world:

 

p.v = dx/dt;

p.F = indifferent;

 

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.

Interface

Ports

Description

p

Translation port.

Causality

 

fixed velocity out

 

Input

 

x

Position [m].

Parameters

 

f

v_initial

Cut-off frequency of the differentiation [Hz].

Initial velocity at the port [m/s].