A Swept Sine event simulates a vehicle driving at a constant speed with a sinusoidal
steering input of constant magnitude but increasing frequency applied.
Output Requests are included to measure the vehicle state variables, tire forces, and tire
state variables. The Altair Driver steers the vehicle and maintains constant speed. A plot
template is available to plot the results.
This test is used to measure the dynamic response of the vehicle to sinusoidal steering
input. Figure 1.
The parameters available in the Swept Sine event are detailed in the following table:
Parameter
Description
Units
Velocity unit selection (Model, m/s, km/h, mph).
Steer Amplitude
Amplitude of the steering input (degrees).
Lean Amplitude*
Amplitude of the demand lean (degrees).
Frequency Rate
The rate of change of frequency (hz/sec) of the sine wave function applied to
the steering wheel.
Minimum frequency
The minimum (initial) frequency sine wave that is applied to the steering
wheel.
Maximum frequency
The maximum (final) frequency sine wave that can be applied to the steering
wheel.
Start time
The start time of the sine wave.
Velocity
The constant speed that the vehicle attempts to maintain during the
event.
End Time
End time of the simulation (calculated using the start time, the frequency
rate, and the max and min frequencies).
Print interval
Time interval of data output to the plot file (.plt) and
graphics file (.h3d).
*Applicable only for Two-wheeler events.
Reference
ISO +7401-2003 - Road vehicles — Lateral transient response test methods — Open-loop test
methods.
