An x-ray beam control apparatus including at least one moveable x-ray attenuating member, and at least one position sensor, wherein the position sensor is configured to contactlessly detect movement of at least one of the attenuating members and to output a signal indicative of the position of the attenuating member.

A power tool including a motor and an impact mechanism. The impact mechanism is coupled to the motor and includes a hammer driven by the motor, and an anvil positioned at a nose of the power tool, and configured to receive an impact from the hammer. The power tool also includes a sensor assembly positioned at the nose of the power tool, and an electronic processor. The sensor assembly includes an output position sensor configured to generate an output signal indicative of a position of the hammer or the anvil. The electronic processor is coupled to the output position sensor and to the motor, and is configured to operate the motor based on the output signal from the output position sensor.

Methods and apparatuses are provided, in which a magnetic field is measured using a coil in a first operating mode and a magnetic field is generated using the coil in a second operating mode in order to test a further magnetic field sensor.

An inductive sensor device has a coil arrangement and sensor electronics for determining a longitudinal position of an at least partially electrically conductive and/or magnetically polarizable object moveable at a distance from a device end face along a device sensitive axis. The arrangement has a substantially planar exciting coil for producing an alternating magnetic field for inducing eddy currents and/or magnetic polarization in the object and a first substantially planar receiving coil substantially parallel to and overlapping the exciting coil. The coils are substantially parallel to the end face. The sensor electronics determine at least one parameter of an exciting coil electrical signal, which is variable owing to an inductive backward effect of the object, at least one parameter of a voltage inducible in the at least first receiving coil based on this effect, and the longitudinal position from the determined signal parameter and the determined voltage parameter.

A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

A displacement sensor includes a coil, an inverter electrically connected to the coil, the inverter being configured to generate an oscillation signal, a reducer electrically connected between the coil and an output terminal of the inverter, the reducer being configured to reduce the strength of the oscillation signal, and a frequency detector electrically connected to the inverter, the frequency detector being configured to detect an oscillation frequency of an oscillator circuit in response to a distance between a measurement target and the coil, the oscillator circuit including the coil, the inverter, and the reducer and having an oscillation frequency of 30 MHz or higher.

A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

A device for inductive position determination comprises a coil, a positional element, a scanning device for determining an inductance of the coil and an evaluation device for determining a position of the positional element in relation to the coil, based on the inductance determined. In certain embodiments, the positional element comprises a ferromagnetic and electrically insulated material.

One inductive sensor is configured to maintain a fixed frequency in a resonant circuit. One apparatus includes an inductance-to-digital converter (LDC). The LDC includes a digital filter to measure an inductance change of a sensor and convert the inductance change to a digital value. The LDC further includes a digital control loop to maintain a fixed frequency in the sensor. The sensor forms an oscillator in the digital control loop. An output of the digital control loop is representative of the inductance change of the sensor.

A rotational sensing system is adaptable to sensing motor rotation based on eddy current sensing. An axial target surface is incorporated with the motor rotor, and includes one or more conductive target segment(s). An inductive sensor is mounted adjacent the axial target surface, and includes one or more inductive sense coil(s), such that rotor rotation rotates the target segment(s) laterally under the sense coil(s). An inductance-to-digital converter (IDC) drives sensor excitation current to project a magnetic sensing field toward the rotating axial target surface. Sensor response is characterized by successive sensor phase cycles that cycle between L.sub.MIN in which a sense coil is aligned with a target segment, and L.sub.MAX in which the sense coil is misaligned. The number of sensor phase cycles in a rotor rotation cycle corresponds to the number of target segments. The IDC converts sensor response measurements from successive sensor phase cycles into rotational data.