Apparatus and method estimate a position of a movable stage. The apparatus comprises: a stator comprising 2D array of sensors arranged relative to one another to provide a plurality of stator-Y oriented sensor columns and a plurality of stator-X oriented sensor rows; a movable stage comprising a first Y-magnet array comprising a plurality of first magnetization segments generally linearly elongated in a stage-Y direction, each first magnetization segment having a stage-Y direction length, L.sub.yy, and a magnetization direction generally orthogonal to the stage-Y direction, the magnetization directions of the plurality of first magnetization segments exhibiting a first magnetic spatial period over .sub.x a stage-X direction width, W.sub.yx, of the first magnet array; and a controller connected to receive information based on an output from each of the sensors and configured to use the information to determine a stator-X direction position of the movable stage.

A lens module is provided, including a holder, a barrel, and an optical element. The optical element is affixed in the barrel, and the holder has a first material. Additionally, the barrel is affixed in the holder and has a second material, wherein the hardness of the first material is greater than the hardness of the second material.

A driving apparatus which reduces power consumption as compared to conventional driving apparatuses. A voltage amplitude of first AC voltages is controlled based on a relative angle between a moving direction of a moving body, which is indicated by a driving command for moving the moving body, and a driving direction of a first vibrator, and a voltage amplitude of second AC voltages is controlled based on a relative angle between the moving direction and a driving direction of a second vibrator. Each of the first vibrator and the second vibrator is controlled based on a deviation between the driving command and a detected position of the moving body while the first AC voltages and the second AC voltages are being controlled. The driving direction of the first vibrator and the driving direction of the second vibrator cross each other.

The invention provides an insert molded lens driving apparatus comprising a lens holder and a driving coil. The lens holder further comprises a plurality of winding posts protruding outwardly therefrom. Each of the plurality of winding posts comprises an insert member partially inserted into the lens holder. The two ends of the driving coil are respectively wound around the plurality of winding posts and thereby to respectively electrically connect to the corresponding insert members. The insert member has a contact or contact area to which a metal component is soldered.

A linear actuator includes dual bucking magnets, dual pole pieces, and dual spacers. The linear actuator includes a coil-and-housing assembly disposed around a magnet assembly. The magnet assembly includes two bucking magnets sandwiched around a central magnet. The central magnet and the bucking magnets may be separated by spacers. A housing is disposed around the magnet assembly. Between the housing and the magnet assembly, a dual coil is wound in two opposing directions to generate additive forces on the magnet assembly.

A half-bridge inverter comprised of upper and lower switches can be placed in linear motor track sections to alternately connect a common point of all drive coils to a full-bus DC power rail (full-bus) and a DC reference, according to PWM command signals, functioning as a virtual mid-bus to allow bi-directional flow of a sum of currents of all drive coils in the section. Separate upper and lower drive switches of the half-bridge inverters that are also connected to drive the drive coils can then be controlled, according to separate PWM command signals, to synchronize their PWM cycles and duty cycle commands with respect to the virtual mid-bus at times when a mover is not present, resulting in zero voltage across the drive coils, or command different duty cycles with respect to the virtual mid-bus when a mover is present, resulting in a desired voltage across the drive coils. The desired voltage can produce a current in the drive coils to electromagnetically propel the mover.

The present invention discloses a displacement device based on Hall-effect sensors and planar motors. The device at least comprises a planar motor stator, a planar motor mover, and a Hall-effect sensor array, a magnet array on the planar motor stator extends on a first plane substantially parallel to a direction X and a direction Y to form a working area, a coil array on the planar motor mover is configured on a second plane parallel to the first plane, an interaction between the coil array and the magnet array causes the planar motor mover to produce a displacement of at least two degrees of freedom within the working area, the magnet array is configured by first magnet blocks and second magnet blocks alternately in rows and columns, the Hall-effect sensor array is composed of a plurality of Hall-effect sensors, and installed on the planar motor mover, a size of the magnet blocks of the magnet array in the direction X is not less than twice a column spacing of the Hall-effect sensor array, and the size of the magnet blocks of the magnet array in the direction Y is not less than twice a row spacing of the Hall-effect sensor array.

The present invention discloses a displacement device based on Hall-effect sensors and planar motors. The device at least comprises a planar motor stator, a planar motor mover, and a Hall-effect sensor array, a magnet array on the planar motor stator extends on a first plane substantially parallel to a direction X and a direction Y to form a working area, a coil array on the planar motor mover is configured on a second plane parallel to the first plane, an interaction between the coil array and the magnet array causes the planar motor mover to produce a displacement of at least two degrees of freedom within the working area, the magnet array is configured by first magnet blocks and second magnet blocks alternately in rows and columns, the Hall-effect sensor array is composed of a plurality of Hall-effect sensors, and installed on the planar motor mover, a size of the magnet blocks of the magnet array in the direction X is not less than twice a column spacing of the Hall-effect sensor array, and the size of the magnet blocks of the magnet array in the direction Y is not less than twice a row spacing of the Hall-effect sensor array.

The present approach includes, in one implementation, a direct drive motor for use in a CT gantry and having a segmented motor stator assembly. The stator segments are connected in series. The stator segments are not independently operable and are instead connected in series to, and operated by, a single frequency controller.

The present approach includes, in one implementation, a direct drive motor for use in a CT gantry and having a segmented motor stator assembly. The stator segments are connected in series. The stator segments are not independently operable and are instead connected in series to, and operated by, a single frequency controller.