A vehicle wheel hub assembly includes an outer member configured to be mounted to a non-rotatable portion of the vehicle and an inner member rotatably supported in the outer member by a bearing and configured to support a vehicle wheel. A first target member is coupled with the inner member, and a first sensor is fixed to the outer member and positioned to sense an angular displacement of the first target member relative to the outer member and to produce a first output signal. A second target member is coupled with the inner member and is spaced axially from the first target member, and a second sensor is fixed to the outer member and positioned to sense an angular displacement of the second target member relative to the outer member and to produce a second output signal.

A speed detection device includes a comparator module, a sensor lead with a node connected to the comparator module, and a limit set module. The limit set module is connected to the sensor lead node and to the comparator by an upper limit lead and a lower limit lead to provide upper and lower limits to the comparator that vary according to amplitude variation in voltage applied to the sensor lead.

A speed detection device includes a comparator module, a sensor lead with a node connected to the comparator module, and a limit set module. The limit set module is connected to the sensor lead node and to the comparator by an upper limit lead and a lower limit lead to provide upper and lower limits to the comparator that vary according to amplitude variation in voltage applied to the sensor lead.

A monitoring system for monitoring one or more properties associated with a rotating shaft is provided. The system includes a first phonic wheel which is mounted coaxially to the shaft for rotation therewith, the first phonic wheel comprising a circumferential row of teeth. The system further includes a first sensor configured to detect the passage of the row of teeth of the first phonic wheel by generating a first alternating measurement signal. The system further includes a processor unit configured to determine the durations of successive first speed samples. Each first speed sample is a block of n successive cycles of the first alternating measurement signal, where n is an integer, and in which the beginning of each cycle is a zero-crossing point from the previous cycle and the end of each cycle is the corresponding zero-crossing point to the next cycle. At least one axial location of the first phonic wheel every m.sup.th tooth of the row of teeth of the first phonic wheel has a circumferential thickness which is different from that of the other teeth of the first phonic wheel, where m is an integer, mn, and m is neither a factor nor a multiple of n. When the first sensor is positioned at said axial location of the first phonic wheel and at any given rotational speed of the first phonic wheel, the durations of the successive first speed samples display a characteristic repeating pattern of longer and shorter sample durations relative to the average duration of the successive first speed samples. The amount by which the longer and shorter sample durations differ from the average duration is in proportion to the amount by which the circumferential thickness of the m.sup.th teeth differs from that of the other teeth at said axial location of the first phonic wheel. The processor unit monitors the properties associated with the rotating shaft from the characteristic repeating pattern.

A monitoring system for monitoring one or more properties associated with a rotating shaft is provided. The system includes a first phonic wheel which is mounted coaxially to the shaft for rotation therewith, the first phonic wheel comprising a circumferential row of teeth. The system further includes a first sensor configured to detect the passage of the row of teeth of the first phonic wheel by generating a first alternating measurement signal. The system further includes a processor unit configured to determine the durations of successive first speed samples. Each first speed sample is a block of n successive cycles of the first alternating measurement signal, where n is an integer, and in which the beginning of each cycle is a zero-crossing point from the previous cycle and the end of each cycle is the corresponding zero-crossing point to the next cycle. At least one axial location of the first phonic wheel every m.sup.th tooth of the row of teeth of the first phonic wheel has a circumferential thickness which is different from that of the other teeth of the first phonic wheel, where m is an integer, mn, and m is neither a factor nor a multiple of n. When the first sensor is positioned at said axial location of the first phonic wheel and at any given rotational speed of the first phonic wheel, the durations of the successive first speed samples display a characteristic repeating pattern of longer and shorter sample durations relative to the average duration of the successive first speed samples. The amount by which the longer and shorter sample durations differ from the average duration is in proportion to the amount by which the circumferential thickness of the m.sup.th teeth differs from that of the other teeth at said axial location of the first phonic wheel. The processor unit monitors the properties associated with the rotating shaft from the characteristic repeating pattern.

An electric power steering system. One example includes a steering control, a steering shaft connected to the steering control, a steering rack, a sensor configured to detect an operating parameter of the steering rack or an electric motor, and an electronic controller. In one example, the electronic controller is configured to receive data indicative of the operating parameter from the sensor, compare the data to a known characteristic curve, the known characteristic curve indicating potential damage to a component of the electric power steering system, and when the data matches the known characteristic curve, output an indication to a user that potential damage has occurred to the component of the electric power steering system.

Method for measuring an angular velocity and/or position comprising: (a) receiving first and second detection signals regarding a vibration from primary and secondary resonance modes of a resonator; (b) implementing at least four control loops using first, second, third and fourth regulators, respectively; and (c) estimating said angular velocity and/or position, as a function of regulator outputs. The first regulator aims at minimizing the difference between the in-phase component of the first detection signal and the product, by a first coefficient C1 that is a function of the azimuthal angle ? in the orthogonal modal base of primary and secondary modes, of a setpoint vibration amplitude of the resonator. The third regulator aims at minimizing the difference between the in-phase component of the second detection signal and the product, by a second coefficient C2 that is a function of ? and the setpoint vibration amplitude. Also, associated gyroscope sensors.

Method for measuring an angular velocity and/or position comprising: (a) receiving first and second detection signals regarding a vibration from primary and secondary resonance modes of a resonator; (b) implementing at least four control loops using first, second, third and fourth regulators, respectively; and (c) estimating said angular velocity and/or position, as a function of regulator outputs. The first regulator aims at minimizing the difference between the in-phase component of the first detection signal and the product, by a first coefficient C1 that is a function of the azimuthal angle ? in the orthogonal modal base of primary and secondary modes, of a setpoint vibration amplitude of the resonator. The third regulator aims at minimizing the difference between the in-phase component of the second detection signal and the product, by a second coefficient C2 that is a function of ? and the setpoint vibration amplitude. Also, associated gyroscope sensors.

A compressor that includes a casing, a compression mechanism provided inside the casing to compress a refrigerant, a rotary shaft transmitting a rotational force to the compression mechanism from a drive source provided outside the casing, a clutch connecting the drive source and the rotary shaft by a magnetic force generated when electric power is applied to the clutch and disconnecting the drive source and the rotary shaft by losing the magnetic force when the electric power applied thereto is cut off, and a rotation measurement means for receiving the magnetic force from the clutch to measure a change in magnetic flux according to the rotation of the rotary shaft and measure a rotational speed of the rotary shaft. Thus, it is possible to measure the rotational speed of the rotary shaft without including a permanent magnet.

A compressor that includes a casing, a compression mechanism provided inside the casing to compress a refrigerant, a rotary shaft transmitting a rotational force to the compression mechanism from a drive source provided outside the casing, a clutch connecting the drive source and the rotary shaft by a magnetic force generated when electric power is applied to the clutch and disconnecting the drive source and the rotary shaft by losing the magnetic force when the electric power applied thereto is cut off, and a rotation measurement means for receiving the magnetic force from the clutch to measure a change in magnetic flux according to the rotation of the rotary shaft and measure a rotational speed of the rotary shaft. Thus, it is possible to measure the rotational speed of the rotary shaft without including a permanent magnet.