Abstract: A control system controls a positioning device displaceable in at least one degree of freedom by a reluctance motor. A force sensing element and a controller adjust force applied by the motor responsive to a force sensing element configured to sense force applied by the motor. The controller receives a signal representing force applied by the motor from the force sensing element, obtain an acceleration trajectory plan associated with a velocity trajectory plan for the positioning device, obtain a force trajectory plan associated with the acceleration trajectory plan, compare the force applied with a required amount of force obtained from the force trajectory, and adjust the amount of force applied by the motor based on the comparison. Related methods are also presented.

Abstract: A control system controls a positioning device displaceable in at least one degree of freedom by a reluctance motor. A force sensing element and a controller adjust force applied by the motor responsive to a force sensing element configured to sense force applied by the motor. The controller receives a signal representing force applied by the motor from the force sensing element, obtain an acceleration trajectory plan associated with a velocity trajectory plan for the positioning device, obtain a force trajectory plan associated with the acceleration trajectory plan, compare the force applied with a required amount of force obtained from the force trajectory, and adjust the amount of force applied by the motor based on the comparison. Related methods are also presented.

Abstract: In a gas gauge, effects due to changes in the local environment are reduced by causing a measurement nozzle and a reference nozzle to react as if they were co-located, or located at approximately the same position. This is achieved by venting the reference nozzle in very close proximity to the measurement nozzle. A reference chamber surrounding the reference plate and reference nozzle is vented at approximately the same location as the measurement nozzle. In an embodiment for use in a vacuum environment, the measurement nozzle is surrounded with an annular ring. The measurement annular ring is connected to an annular ring around the reference nozzle, which acts to co-locate the reference nozzle and the measurement nozzle. To avoid choked flow, another annular ring or rings may be placed around the measurement annular ring.

Abstract: In a gas gauge, effects due to changes in the local environment are reduced by causing a measurement nozzle and a reference nozzle to react as if they were co-located, or located at approximately the same position. This is achieved by venting the reference nozzle in very close proximity to the measurement nozzle. A reference chamber surrounding the reference plate and reference nozzle is vented at approximately the same location as the measurement nozzle. In an embodiment for use in a vacuum environment, the measurement nozzle is surrounded with an annular ring. The measurement annular ring is connected to an annular ring around the reference nozzle, which acts to co-locate the reference nozzle and the measurement nozzle. To avoid choked flow, another annular ring or rings may be placed around the measurement annular ring.

Abstract: A system and method are used to levitate and translate a stage within a chamber using a motor assembly coupled to a balance mass assembly. The balance mass assembly is positioned adjacent the chamber. The motor assembly includes a stator and a coil. One of the stator and the coil are coupled to the stage on a first side of a wall of the chamber. The other of the stator and the coil are coupled to the balance mass assembly on a second side of the wall of the chamber. A magnetic assembly coupled to the stage allows the stage to levitate within the chamber. Once levitated, the stage is translated based on the interaction of the magnets and an energized coil.

Abstract: A system and method are used to levitate and translate a stage within a chamber using a motor assembly coupled to a balance mass assembly. The balance mass assembly is positioned adjacent the chamber. The motor assembly includes a stator and a coil. One of the stator and the coil are coupled to the stage on a first side of a wall of the chamber. The other of the stator and the coil are coupled to the balance mass assembly on a second side of the wall of the chamber. A magnetic assembly coupled to the stage allows the stage to levitate within the chamber. Once levitated, the stage is translated based on the interaction of the magnets and an energized coil.