Calculator Inputs
Formula Used
The vibration dose value, or VDV, emphasizes shock and transient vibration by raising acceleration to the fourth power before time integration.
Discrete form:
VDV = k × (Σ(ai4 × ti) × N)1/4
Where:
- ai = RMS acceleration for each segment in m/s²
- ti = segment duration in seconds
- N = repeated exposure count per day
- k = axis multiplying factor
This calculator combines up to five exposure segments, applies the selected axis multiplier, and compares the final daily VDV against user-defined action and limit values.
How to Use This Calculator
- Enter RMS acceleration for each operating segment.
- Enter the duration of each segment in minutes.
- Select the relevant body axis or enter a custom multiplier.
- Set how many similar exposures occur during the day.
- Adjust action and limit thresholds if your project uses custom criteria.
- Press calculate to show the result above the form.
- Review the contribution table and the Plotly chart.
- Export the calculation as CSV or PDF for reporting.
Example Data Table
| Segment | Machine Phase | Acceleration RMS (m/s²) | Duration (min) |
|---|---|---|---|
| 1 | Startup | 0.65 | 15 |
| 2 | Loaded operation | 0.92 | 35 |
| 3 | Rough surface transit | 1.25 | 18 |
| 4 | Idle movement | 0.48 | 22 |
| 5 | Shutdown | 0.58 | 10 |
You can use these sample values to test the calculator and verify how segment duration and higher acceleration spikes influence the final VDV.
Frequently Asked Questions
1. What is vibration dose value?
VDV is a vibration metric that weights shocks heavily by using the fourth power of acceleration. It is useful when exposure contains bumps, jolts, or intermittent peaks.
2. Why use VDV instead of only RMS acceleration?
RMS acceleration can understate short, intense shocks. VDV better reflects discomfort and potential risk where transient peaks contribute significantly to overall exposure severity.
3. What units does this calculator return?
The result is shown in m/s1.75. That unit comes from taking the fourth root after integrating acceleration to the fourth power over time.
4. Why are axis multipliers included?
Human response differs by measurement direction. Multipliers allow the calculation to reflect directional weighting, especially for whole-body vibration assessments in engineering environments.
5. Can I combine several operating phases?
Yes. This page accepts five exposure segments. Each segment contributes a fourth-power time term, and all segments are combined into one daily value.
6. What does exposures per day mean?
It represents how many times the same exposure pattern repeats in one working day. Increasing repetitions raises the daily VDV value.
7. Are the action and limit values editable?
Yes. The default thresholds are common reference points, but you can enter project-specific, contractual, or internal assessment limits when needed.
8. When should I export CSV or PDF?
Export the results when preparing reports, documenting field measurements, sharing findings with safety teams, or keeping calculation records for audits and reviews.