A weight-based occupant characterization method reliably distinguishes
between large and small adult occupants by dynamically adjusting a
threshold used to distinguish between large and small adult occupants.
The threshold adjustments effectively increase the separation between the
detected weight and the threshold, minimizing oscillation of the
determined characterization following an initial occupant
characterization. A learning routine gradually adjusts the threshold up
to a predefined maximum adjustment so long as the detected weight is
within a tolerance or hysteresis band, or a locking routine produces a
step change adjustment of the threshold when the detected weight is
outside the tolerance or hysteresis band for at least a predefined time.