Description
Convert moment of inertia with supplied unit factors.
Mechanical inertia, torque and muscle-force projections require compatible axes, origins and geometric assumptions. A parallel-axis contribution, planar moment or ideal pennation factor is one local model term rather than a full anatomical load or muscle-activation calculation.
Convert moment of inertia with supplied unit factors.
When to use this tool
Use Segment Inertia Unit Factor when evaluating the stated segment, moment, inertia or ideal muscle-geometry term.
How to use the tool and how it works
- Enter inertia, massUnitFactor, lengthUnitFactor. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read convertedInertia. Use the output convention below.
Convert moment of inertia with supplied unit factors. Require inertia >= 0 and positive mass/length factors; convertedInertia = inertia*massUnitFactor*lengthUnitFactor².1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| inertia | Inertia | Required. Finite number; minimum 0. |
| massUnitFactor | Mass Unit Factor | Required. Finite number; strictly above 0. |
| lengthUnitFactor | Multiply a source length by this factor for target units; inertia uses its square. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| convertedInertia | Converted Inertia | Required. Finite number. |
{
"input": {
"inertia": 2,
"massUnitFactor": 1,
"lengthUnitFactor": 0.01
},
"output": {
"convertedInertia": 0.0002
}
}Limitations and assumptions
- Factors convert source units to target units; no anatomical axis transformation or physical inertia measurement is performed.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use verified anatomy and calibration, a consistent coordinate frame and a complete appropriate mechanical model for actual loading or clinical interpretation.
References
Similar or alternative tools
- Segment Inertia Parallelaxis Reference Offset
Return inertia about a shifted parallel axis.
- Segment Mass Moment Contribution
Return a parallel-axis inertia contribution.