US Patent 7197944 Hub unit with sensor

A sensor device including a resolver having a rotor provided on a rotation-side raceway member of a hub unit and a stator provided on a stationary-side raceway member of the unit, and a processing circuit for processing a signal to be output in accordance with an air gap between the stator and the rotor. The processing circuit has a wheel ground contact load calculating unit for determining the ground contact load on a wheel from the air gap between the stator and the rotor.