Trackway Gait Transition Speed Threshold

Propagate caller hip-height and transition-Froude bounds into threshold-speed scenarios and compare a supplied track speed; not the existing simple Froude calculation or a universal walking/running determination.

Description

Froude-based transition speed depends on hip height and gravity.

Froude-based transition speed depends on hip height and gravity. Uncertain height and transition criteria produce scenarios rather than a universal gait label.

When to use Trackway Gait Transition Speed Threshold

Use this tool to propagate caller hip-height and transition-Froude bounds into threshold-speed scenarios and compare a supplied track speed; not the existing simple Froude calculation or a universal walking/running determination.

Prepare the fossil measurements or occurrence records and the chosen calibration parameters. Retain the stated coordinate, age and measurement conventions.

How to use Trackway Gait Transition Speed Threshold and understand its results

Prepare the fossil measurements or occurrence records and the chosen calibration parameters. Retain the stated coordinate, age and measurement conventions.
Enter hipHeightScenarioBoundsM, callerTransitionFroudeBounds, gravityMPerSecondSquared, observedTrackSpeedMPerSecond using the field table and calculation rules, then run the tool.
Read gaitTransitionSpeedScenarioBoundsMPerSecond, trackSpeedPositionCode. 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
hipHeightScenarioBoundsM	Hip height scenario bounds m	list of number	Required
callerTransitionFroudeBounds	Caller transition froude bounds	list of number	Required
gravityMPerSecondSquared	Gravity m per second squared	number	Required
observedTrackSpeedMPerSecond	Observed track speed m per second	number	Required

Use two ordered positive bound pairs, positive gravity and nonnegative track speed. Code 0 means below the lower bound, 2 above the upper, and 1 inside including endpoints.^[1]

speed bounds = sqrt(gravity × hip-height bounds × transition-Froude bounds)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
gaitTransitionSpeedScenarioBoundsMPerSecond	Gait transition speed scenario bounds m per second	list of number
trackSpeedPositionCode	Track speed position code	number

json

{
  "input": {
    "hipHeightScenarioBoundsM": [
      1,
      4
    ],
    "callerTransitionFroudeBounds": [
      0.25,
      1
    ],
    "gravityMPerSecondSquared": 1,
    "observedTrackSpeedMPerSecond": 0.75
  },
  "output": {
    "gaitTransitionSpeedScenarioBoundsMPerSecond": [
      0.5,
      2
    ],
    "trackSpeedPositionCode": 1
  }
}

Limitations and assumptions

Caller transition assumptions do not determine actual walking or running.

Numbers and computed results must be finite; overflow produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Alexander Footprint Speed Estimator: Evaluate Alexander’s published footprint-stride speed approximation with explicit estimated hip height; stride is successive same-foot spacing, not step length, and model does not prove gait or actual speed. For a complementary task, use Hypsodonty Index: Compute caller convention unworn crown height/buccolingual width hypsodonty and screen a comparison band; observed worn height is a different tool, and neither index establishes diet.

References

Trackway Gait Transition Speed Threshold — tool.io

Similar or alternative tools

Alexander Footprint Speed Estimator
Evaluate Alexander’s published footprint-stride speed approximation with explicit estimated hip height; stride is successive same-foot spacing, not step length, and model does not prove gait or actual speed.
Hypsodonty Index
Compute caller convention unworn crown height/buccolingual width hypsodonty and screen a comparison band; observed worn height is a different tool, and neither index establishes diet.