A top drive system comprising a drilling rig, and a top drive unit operatively associated with the drilling rig. The top drive includes a top drive housing, and a rotatable member having a first member portion within the top drive housing, and a second member portion extending outward from the top drive housing. There is a sensor assembly disposed within the top drive housing, the assembly comprising a sensor configured to provide an output signal associated with an at least one parameter of the top drive. The first member portion is configured with a profile sensed by the sensor assembly.

A top drive system comprising a drilling rig, and a top drive unit operatively associated with the drilling rig. The top drive includes a top drive housing, and a rotatable member having a first member portion within the top drive housing, and a second member portion extending outward from the top drive housing. There is a sensor assembly disposed within the top drive housing, the assembly comprising a sensor configured to provide an output signal associated with an at least one parameter of the top drive. The first member portion is configured with a profile sensed by the sensor assembly.

A method for determining a speed using a measurement-sensor in a vehicle, the measurement-sensor including at least one coil and a ferromagnetic-transmitter-element, including: changing the inductance of the coil, using an inductive-speed-sensor having at least the coil and the ferromagnetic-transmitter-element; recording a change in the coil inductance, and determining the speed based on the changed coil inductance; in which in each case one inductive-speed-sensor is a wheel-speed-sensor for at least two vehicle wheels, and in which a reversal of the direction of movement of the ferromagnetic-transmitter-element as to the coil or a reversal of the direction of travel of the vehicle from forward travel to reverse travel or from reverse travel to forward travel is recognized based on at least one temporal-phase-offset of the temporal-profiles of the inductances recorded by the wheel-speed-sensors of the at least two wheels. Also described is a related driver assistance system and vehicle.

An eddy current sensor for a rotary shaft and a rotary shaft apparatus. The eddy current sensor includes: a housing; one or more position detecting probes provided on the housing; and a rotating speed detecting probe provided on the housing. The eddy current sensor integrates the position detecting probe and the rotary speed detecting probe, such that while the eddy current sensor is detecting position displacement of the rotary shaft, the eddy current sensor may also simultaneously detect the rotating speed of the rotary shaft, which facilitates detecting and monitoring the rotary shaft more comprehensively. The detected position data and rotating speed data of the rotary shaft correspond to each other at any time, such that the working state of the rotary shaft may be analyzed more intensively.

A state observation device (30) uses an ADC (37) to digitize a detection signal from a gap sensor (21) at a low-speed sampling period and uses a separation unit (38) to separate the digitized detection signal into vane detection signals considered to be for the detection of a vane of a compressor impeller and non-vane detection signals considered not to be for the detection of a vane. Further, the determination unit (39) extracts a vane peak detection signal considered to be for a vane peak by comparing a vane detection signal with vane detection signals corresponding to other vanes and non-vane detection signals, and a shaft vibration and tip clearance are determined as states of the compressor impeller on the basis of the extracted vane peak detection signal. Thus, the state observation device (30) is capable of observing the state of a rotary machine without carrying out high-speed sampling.

A sensor device for measuring the rotational speed at a wheel of a vehicle has a sensor carrier with an active sensor for actively sensing the rotation of a pole wheel rotating along with the wheel to measure rotational speed. The sensor carrier is constructed and arranged such that it can be clamped in the region of the wheel to permit the active sensor to be used without requiring complex adjustment operations.

A sensor device for measuring the rotational speed at a wheel of a vehicle has a sensor carrier with an active sensor for actively sensing the rotation of a pole wheel rotating along with the wheel to measure rotational speed. The sensor carrier is constructed and arranged such that it can be clamped in the region of the wheel to permit the active sensor to be used without requiring complex adjustment operations.

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.

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.

A transconductor converts voltage on an inductive sensor to a proportional current using two “coupling” capacitors. Responsive to movement of an electrically conductive target from the null position a resonant current is formed between the two sensor coils. A single differential transistor pair switched by periodic drive signals commutes the net alternating current at the single input to direct current.