Rotational Position
Forced angular position of a flange
|
Description
|
|
This component generates a forced angular position at according to an input signal that specifies a reference angle, .
When the exact parameter is true, the reference angle is used as-is. This is only possible if the input signal is defined by a twice-differentiable function.
When the exact parameter is false (the default value), the reference angle is filtered and the second derivative of the filtered curve is used to compute the reference acceleration of the flange. This second derivative is not computed by numerical differentiation but by an appropriate realization of the filter. For filtering, a second-order Bessel filter is used. The critical frequency of the filter (cut-off frequency) is defined by the parameter, . This value should be higher than the essential low frequencies in the signal.
The component equations are
|
|
Connections
|
|
Name
|
Description
|
Modelica ID
|
|
Input signal. The reference angle of .
|
phi_ref
|
|
Right driving flange. The flange axis is directed out of the cut plane.
|
flange
|
support
|
Conditional Support Flange
|
support
|
|
|
|
|
Variables
|
|
Symbol
|
Units
|
Description
|
Modelica ID
|
|
|
Angular acceleration of flange with respect to support
|
a
|
|
|
Angular velocity of with respect to
|
w
|
|
|
Angle of with respect to
|
phi
|
|
|
|
|
Parameters
|
|
Symbol
|
Default
|
Units
|
Description
|
Modelica ID
|
Use Support Flange
|
false
|
-
|
Enable flange
|
useSupport
|
|
|
-
|
Permitted values:
•
|
true - reference angle is treated exactly
|
•
|
false - input signal is filtered
|
|
exact
|
|
|
|
The critical frequency of the input signal filter when the exact parameter is set to false.
|
f_crit
|
|
|
|
|
Constants
|
|
Symbol
|
Value
|
Units
|
Description
|
|
1.3617
|
|
Bessel filter coefficient
|
|
0.6180
|
|
Bessel filter coefficient
|
|
|
|
Critical frequency in natural units
|
|
|
|
|
Download Help Document
Was this information helpful?