MHB Longitudinal excitation of a sine wave

AI Thread Summary
The discussion centers on modeling the longitudinal excitation of a sine wave in a quarter car model driving over a sinusoidal road. The vertical excitation is represented as ze^(jωt), and participants suggest a similar approach for the longitudinal direction. The proposed formula for the longitudinal excitation includes an average speed component and an amplitude term, expressed as x = v_x + A_x e^(jω_x t). This allows for a comprehensive representation of both vertical and longitudinal excitations in the model. Participants are encouraged to share further insights or clarifications on the topic.
Nino1
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Hi!
This is a problem regarding a quarter car model driving over a sinusoidal road excitation.

A sinusoidal excitation can be written on the form ze^(jωt), z being vertical. I would like to write the longitudinal excitation of a sine wave on the same form?

Any hints and tips are much appreciated.
 
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Nino said:
Hi!
This is a problem regarding a quarter car model driving over a sinusoidal road excitation.

A sinusoidal excitation can be written on the form ze^(jωt), z being vertical. I would like to write the longitudinal excitation of a sine wave on the same form?

Any hints and tips are much appreciated.

Welcome to MHB, Nino! :)

Looks like your z-coordinate is of the form $$z=A_z e^{j\omega_z t}$$, where $A_z$ is an amplitude and $\omega_z$ is the angular frequency for the excitation in the z direction.

If that was your intention, you can use a similar formula for your x coordinate.
Assuming your car model drives in the x direction with some average speed $v_x$, a possible formula for the x coordinate is:
$$x = v_x + A_x e^{\displaystyle j\omega_x t}$$
 
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