Electromagnetic apparatus for measuring angular position

An apparatus for measuring an angular position about a rotation axis, and related physical parameters, of a movable part, the apparatus comprising at least two electrodynamic targets, the electrodynamic targets being configured as segments having angular widths, the electrodynamic targets having an angular position in a rotation plane that is representative of the angular position of the movable part;

• in proximity to the electrodynamic targets, at least two resonators formed by plane slow-wave structures connected to at least one RF oscillator and a measuring circuit, further characterized in that:
• the resonators being formed by coupled slow-wave structures, each having an angular width, and placed parallel to the rotation plane,
• internal ends of the coupled slow-wave structures being connected to one another, their external ends forming terminals connected to the measuring circuit,
• at least two of the electrodynamic targets of approximately the same angular width being placed parallel to the resonators at approximately the same angular position as one another,
• the electrodynamic targets having a non-symmetrical configuration with respect to the rotation axis,
• the resonators having electrodynamic parameters, variation in the angular position of at least one of the electrodynamic targets resulting in variation in the electrodynamic parameters of at least one of the resonators,
• the measuring circuit converting changes in the electrodynamic parameters of the resonators into at least two informative signals,
• the measuring circuit comparing the informative signals and converting their difference into an electrical output indicative of the angular position of the target.