🔍 Impact Injury Severity Speed/Height Simulator

Impact Event — Collision or Fall Onset

Every trauma reconstruction starts with one moving body meeting one fixed surface.

• 0–120: Vehicle impact speeds (km/h modeled range)
• 0–30: Fall heights (meters modeled range)
• 40–120: Body mass range (kilograms modeled)
• <200: Contact duration (milliseconds typical)

Two impact archetypes

Vehicle collisions and falls differ, but both deliver sudden energy.

Why speed and height matter

Both variables set the velocity at the moment of contact.

Doubling speed quadruples kinetic energy, not doubles it.

Kinetic Energy Calculated From Mass and Motion

Energy at impact is computed directly from mass and either speed or fall height.

• ½mv²: Vehicle formula (mass × velocity squared)
• mgh: Fall formula (mass × gravity × height)
• 9.81: Gravity constant (m/s² used in model)
• Joules: Energy unit (standard SI energy unit)

Kinetic energy formula

½mv² converts vehicle speed and body mass into joules.

Potential energy formula

mgh converts fall height into the same joule scale.

Both formulas feed one shared severity model.

Energy Transfer Into Tissue and Bone

At contact, kinetic energy transfers into the body at the point of impact.

• <50: Transfer window (ms for rigid contact)
• Contact: Peak force zone (point concentrates load)
• High-g: Deceleration (sudden velocity change)
• Deform: Tissue response (then rebound or fail)

Contact point loading

Energy concentrates wherever the body first meets the surface.

Deceleration and injury

Faster stopping means more force delivered per second.

Shorter stopping distance always raises peak force.

Injury Severity Correlation With Impact Energy

Higher calculated impact energy correlates with more severe injury patterns.

• <400 J: Minor threshold (bruising, soft tissue)
• 1.2–3 kJ: Severe threshold (fracture likely)
• 3–6 kJ: Critical threshold (multi-system trauma)
• >6 kJ: Fatal threshold (non-survivable range)

Severity bands

Energy is grouped into five escalating injury bands.

Not a hard cutoff

Bands are statistical tendencies, not certainties.

Real cases vary with anatomy and impact angle.

Forensic Injury Estimate From Impact Energy

A likely injury severity and survivability estimate closes the reconstruction.

• 5: Output classes (minor through fatal)
• Exponential: Survivability model (decays with energy)
• Forensic: Use case (trauma reconstruction)
• Estimate: Confidence (not a diagnosis)

Reading the estimate

Severity and survivability are read straight off the gauge.

Limits of the model

This is an educational estimate, not a medical finding.

Always defer to actual clinical or forensic exam.