Leg Stiffness
Calculate leg stiffness from the supplied measurements.
Description
A force-to-displacement stiffness estimate treats the leg as a linear spring.
A force-to-displacement stiffness estimate treats the leg as a linear spring. The supplied vertical excursion determines the denominator.1
Calculate leg stiffness from the supplied measurements.
When to use Leg Stiffness
Use this tool to calculate leg stiffness from the supplied measurements.
Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
How to use Leg Stiffness and understand its results
- Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
- Enter peakVerticalForceNewtons, verticalDisplacementMeters using the field table and calculation rules, then run the tool.
- Read legStiffnessNewtonsPerMeter. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| peakVerticalForceNewtons | Peak vertical force | number | Required |
| verticalDisplacementMeters | Vertical displacement | number | Required |
Enter finite values with nonzero displacement. Return N/m; signed values are accepted.
stiffness=peakForce/verticalDisplacement Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| legStiffnessNewtonsPerMeter | Leg stiffness (N/m) | number |
{
"input": {
"peakVerticalForceNewtons": 2400,
"verticalDisplacementMeters": 0.12
},
"output": {
"legStiffnessNewtonsPerMeter": 20000
}
}Limitations and assumptions
This is not a full leg-compression or force-trace fit. Use a consistent physical displacement convention.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Vertical Loading Rate: Calculate vertical loading rate from the supplied measurements. For a complementary task, use Foam Energy Return: Calculate foam energy return from the supplied measurements.
References
-
Leg Stiffness — tool.io
Similar or alternative tools
- Vertical Loading Rate
Calculate vertical loading rate from the supplied measurements.
- Foam Energy Return
Calculate foam energy return from the supplied measurements.