Abstract: An angular position detector includes a cylindrical rotor having an axis of rotation and a first ring with a plurality of alternating teeth and valleys, a first first-ring magnetic sensor having a sensor surface facing the first ring, the first first-ring magnetic sensor being configured to produce a first signal in response to movement of the first ring past the first first-ring magnetic sensor, a second first-ring magnetic sensor having a sensor surface facing the first ring and being configured to produce a second signal in response to movement of the first ring past the second first-ring magnetic sensor, the second first-ring magnetic sensor being circumferentially offset from the first first-ring magnetic sensor by a first angle and a controller operatively connected to the first and second first-ring magnetic sensors and configured to produce a first output signal based on the first and second signals.

Abstract: A diagnostic scanning apparatus includes a hollow rotor sized to receive a patient. First and second flanges are connected to and extend radially outward from the rotor in a spaced-apart relationship, each of the first and second flanges including, at least in part, a magnetically-permeable material. A radiation source is affixed to the first flange and/or the rotor. A first axial actuator generates a variable magnetic field, is fixedly disposed adjacent to the first flange and can magnetically pull the first flange in a first axial direction of the rotor. A second axial actuator generates a variable magnetic field, is fixedly disposed adjacent to the second flange and can magnetically pull the second flange in a second axial direction of the rotor that is opposite of the first axial direction. The first and second axial actuators are both at least substantially disposed between the first and second flanges.