Signal definition

@SIGNAL_DEFINITION {
@SIGNAL_NAME {SignalName} {
@SENSOR_NAME {SensorName}
@CHANNEL_NUMBER {nc}
@SIGNAL_PRECONDITIONING_NAME {PreConName}
@SIGNAL_CONDITIONING_NAME {CondName}
@COMMENTS {CommentText}
}
}

Notes

  1. A signal extracts a single time history from sensor SensorName. Plots of the signal output will be generated, if requested by the plotting control parameters. The plot associated with a signal is a two-dimensional graph: time is plotted along the x-axis and the quantity evaluated by the signal is plotted along the y-axis. The labeling of the x- and y-axes of the signal plot are inherited from those of the sensor SensorName. Signals are processed in the signal processing phase of the analysis.
  2. Sensors typically extract six time dependent quantities at a particular location of the system. The channel number,
    1 ≤ nc ≤ 6,
    specifies which of these six quantities will be used for the signal. In summary, the combination of a sensor and a channel number identify a unique signal.
  3. The time history of the signal can be modified in two ways.
    • If signal preconditioning, PreConName, the data will be accordingly preconditioned.
    • If a signal conditioning CondName is defined, further conditioning of the signal will be performed.
  4. Two options are available for signal conditioning.
    • If signal conditioning CondName corresponds to a Fourier analysis, the time history of the signal will be Fourier analyzed accordingly.
    • If signal conditioning CondName corresponds to a filter, the time history of the signal will be filtered accordingly.
  5. It is possible to attach comments to the definition of the object; these comments have no effect on its definition. If comments are defined for a graph, they are repeated as part of the graph title.

Example

Example 1

Sensor SensorBeam2Forces extracts the three forces and three moments at Beam2 mid-span. Next, the signal SignalBeam2Forces extract the first channel of this sensor, corresponding to the axial force in the beam. Figure 1 shown the output generated by the sensor, and fig.2 that created by the signal.

SENSOR_DEFINITION {
@SENSOR_NAME {SensorBeam2Forces} {
@OBJECT_NAME {Beam2}
@SENSOR_TYPE {FORCES}
@ETA_COORDINATE {0.5}
}
}
SIGNAL_DEFINITION {
@SIGNAL_NAME {SignalBeam2Forces} {
@SENSOR_NAME {SensorBeam2Forces}
@CHANNEL_NUMBER {1}
}
}
Figure 1. Output created by sensor SensorBeam2Forces.                        Figure 2. Output created by signal SignalBeam2Forces.

Example 2

Sensor SensorRotationC extracts the relative rotation at a revolute joint. Next, the signal SignalRotationC extract the fourth channel of this sensor, corresponding to the relative rotation at the joint. Figure 3 shown the output generated by the sensor, and fig.4 that created by the signal. Note the effects of the preconditioning on the signal plot.

SIGNAL_PRECONDITIONING_DEFINITION {
@SIGNAL_PRECONDITIONING_NAME {PreconRotationC} {
@INITIAL_TIME {2.51327412287183}
@TIME_NORMALIZATION {3.4906585039887e-03}
@NORMALIZED_TIME_RANGE {0.0, 360}>
@TIME_AXIS_LABEL {REVOLUTIONS [DEG]}
}
}
SIGNAL_DEFINITION {
@SIGNAL_NAME {SignalRotationC} {
@SENSOR_NAME {SensorRotationC}
@CHANNEL_NUMBER {4}
@SIGNAL_PRECONDITIONING_NAME {PreconRotationC}
}
}
Figure 3. Output created by sensor SensorRotationC.                        Figure 4. Output created by signal SignalRotationC.