Position encoder based on halbach magnetic element

A Halbach-based magnetic position sensor, comprising:

• a Halbach magnetic element having a spatially rotating magnetization pattern along an extent thereof, the magnetization pattern being effective to produce a focused and augmented magnetic field on a working side of the Halbach magnetic element relative to a magnetic field on a non-working side, the Halbach magnetic element having a continuously magnetized, closed curve configuration surrounding an inside area as the working side and defining an outside area as the non-working side;
• and
• a sensing element on the working side of the Halbach magnetic element and being co-configured with the Halbach magnetic element for relative motion therebetween, the sensing element including encoder circuitry and one or more magnetic sensors, the sensors being configured to sense the working-side magnetic field and produce corresponding one or more sensor signals, the encoder circuitry being configured to translate the sensor signals into one or more position signals indicating relative position between the sensing element and the Halbach magnetic element,
• the position sensor having an on-axis arrangement in which the sensing element and the Halbach magnetic element are aligned with a rotational axis of a rotating member whose rotational position is to be sensed.