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THE FEUTEX TOOLKIT

Ringdown Damping Estimate

Estimate logarithmic decrement and damping from separated vibration peaks.

Mechanical workspace● Runs in your browser
01 Your input
02 Your result
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Formulaδ=ln(x₁/xn)/n; ζ=δ/√(4π²+δ²).
Sources and model references

Worked example

Inputs

First peak magnitude
10 mm
Later peak magnitude
5 mm
Number of cycles between peaks
5
Damped oscillation period
0.2 s

Expected results

Per-cycle logarithmic decrement
0.1386294361
Damping ratio
0.0220581917
Undamped angular frequency
31.42357225 rad/s

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter every input in the labeled units; use measured or independently specified properties.
  2. Check the stated model assumptions before calculating.
  3. Interpret the output as a model estimate and verify it independently for the intended application.

Try this example

{
  "first": 10,
  "last": 5,
  "cycles": 5,
  "period": 0.2
}

Accuracy and scope

Same-sign envelope peaks of an underdamped linear viscous single-mode ringdown. Educational engineering estimate only; not structural or safety certification, equipment selection, or operating recommendations.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.