How this calculator works
On level ground, balancing moments about an axle determines the longitudinal centre of mass. Left and right scale totals similarly give its lateral position. The raised-axle mode compares the load on the axle that stays down before and after tilting. It assumes a rigid chassis, unchanged mass distribution, equal wheel radii and negligible suspension movement. Scale readings are mass equivalents; uniform gravity cancels from the ratios.
Formula
x_from_front = L m_rear/(m_front + m_rear); y_from_left = track m_right/m_total. Height = wheel radius + L(delta down-axle scale mass)/(m_total tan tilt); sin tilt = lift/L.
Worked example
With 600 kg on the front axle, 400 kg on the rear and a 2.5 m wheelbase, the centre lies 1 m behind the front axle. A 1.5 m track with 600 kg left and 400 kg right places it 0.6 m from the left wheels.
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Frequently asked questions
Are scale readings forces or masses?
Use mass-equivalent readings in consistent units. The force ratio is the same because gravity cancels.
What changes during a tilt test?
The axle that stays down gains load if the centre of mass is above axle height. The calculation uses that load change.
Can fuel or suspension movement affect the height estimate?
Yes. Any movement of mass or suspension geometry violates the fixed-body assumptions and can materially affect the result.