Free · Physics models
Rigid Vehicle Center from Wheel Scales
Infer longitudinal, lateral and raised-axle center coordinates from wheel-scale mass equivalents.
- Formula & worked example
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Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
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Formula and method
A 1,000-kg vehicle with 600 kg on the front axle, 400 kg on the rear and a 2.5-meter wheelbase places its center 1 meter behind the front axle.
Static moment balance locates the center; raised-axle readings and tilt geometry estimate its height.
Worked example
Enter these known values and leave the other values blank.
- Car weight
- 1000 kg
- Front axle weight
- 600 kg
- Rear axle weight
- 400 kg
- Wheelbase (L)
- 2.5 m
- Car weight
- 1000 kg
- Distance a
- 1 m
- Distance b
- 1.5 m
Assumptions and limitations
- Readings are scale mass equivalents taken on a rigid vehicle with consistent loading. Wheelbase and track are positive and nonzero axle elevation is required for a height estimate.
- Front-raised and rear-raised branches use different loaded-axle readings; wheel radius sets the height reference. Suspension movement and changing tire radius bias the ideal result.
- This coordinate estimate does not determine rollover limits, handling stability or structural loading.
- Clear the unknown numerical field before using a supported inverse; selection controls retain their captured branches.
Common questions
What assumptions matter for this model?
Readings are scale mass equivalents taken on a rigid vehicle with consistent loading. Wheelbase and track are positive and nonzero axle elevation is required for a height estimate.
What does this model leave out?
This coordinate estimate does not determine rollover limits, handling stability or structural loading.
References
- SAE: vehicle center-of-gravity wheel-scale method
- NASA: mass-weighted center of gravity
- Calculation definition and unit reference
Model requirements: Wheelbase must be positive. Total vehicle mass must be positive. Authored accessible explanations preserve each captured diagram mode and its geometric relationships.