A method of monitoring the health of an aircraft propeller whilst the propeller is in operation, the propeller having a plurality of blades extending radially outwardly from hub arms of a propeller hub, which in turn extend radially outwardly from a central axis extending through the propeller and a propeller drive shaft, is provided. The method comprises obtaining measurements representative of the strain in each of at least some of the hub arms using strain sensors, each of the strain sensors being provided on a respective hub arm. A corresponding propeller health monitoring system, an aircraft propeller comprising the system and an aircraft comprising the propeller are also provided.

A method of monitoring the health of an aircraft propeller whilst the propeller is in operation, the propeller having a plurality of blades extending radially outwardly from hub arms of a propeller hub, which in turn extend radially outwardly from a central axis extending through the propeller and a propeller drive shaft, is provided. The method comprises obtaining measurements representative of the strain in each of at least some of the hub arms using strain sensors, each of the strain sensors being provided on a respective hub arm. A corresponding propeller health monitoring system, an aircraft propeller comprising the system and an aircraft comprising the propeller are also provided.

Provided are a device and a measuring method for measuring an unbalanced moment on a bottom surface of a circular valve core. The device includes a diverging shaped tube, a water tank, a transparent tube, spring dynamometers, laser sources, a circular valve core, and a high-speed camera with a camera stand. Inner shackles and the laser sources are evenly distributed on an outer side of the circular valve core of the device, the spring dynamometers are connected with the inner shackles and with the outer shackles evenly distributed on an inner wall of the transparent tube. The method records an unbalanced state of the circular valve core under an impact of water flow from different orientations with the high-speed camera on the camera stand, the location of the laser point on the outer wall and a tension force of the spring dynamometer are read to calculate a torque of the circular valve core.

A method for damping dependent scaling for reducing wheel imbalance in a steering system includes determining roadwheel speed energy using a roadwheel speed signal and determining that the roadwheel speed energy is greater than a predetermined energy threshold, and in response: adjusting the roadwheel speed signal; and computing a wheel imbalance reduction command using the adjusted roadwheel speed signal. The method also includes determining that the roadwheel speed energy is not greater than the predetermined energy threshold, and in response computing the wheel imbalance reduction command using the roadwheel speed signal. The method also includes computing a motor torque command using the wheel imbalance reduction command, the motor torque command used to generate a corresponding amount of torque at a handwheel.

A device (10) and method for sensor diagnostic monitoring and detection of an imbalance of a rotating machine (1) has steps of (a) detecting acceleration signals (Sb) of the housing (2) or of a non-rotating component of the rotating machine (1) by a sensor (20); (b) detecting signals (Sd) for the determination of the rotation speed of the rotating machine (1) by a second sensor; and (c) supplying and evaluating of sensor signals (Sb, Sd) by an evaluation unit (40, 50, 60). An acceleration component that is acquired occurs with the rotation speed of the rotating machine. This component is compared with a predetermined limit value.

A device (10) and method for sensor diagnostic monitoring and detection of an imbalance of a rotating machine (1) has steps of (a) detecting acceleration signals (Sb) of the housing (2) or of a non-rotating component of the rotating machine (1) by a sensor (20); (b) detecting signals (Sd) for the determination of the rotation speed of the rotating machine (1) by a second sensor; and (c) supplying and evaluating of sensor signals (Sb, Sd) by an evaluation unit (40, 50, 60). An acceleration component that is acquired occurs with the rotation speed of the rotating machine. This component is compared with a predetermined limit value.

Predictive models for diagnosing the unbalance state in an aircraft engine such as a jet engine based on engine vibrations and other known and/or determinable parameters are disclosed. Also disclosed are methods for developing the predictive model and using the model to identify aircraft engine unbalance.

A mixed-flow turbine wheel includes: a plurality of rotor blades disposed on a circumferential surface of the hub at intervals in a circumferential direction and configured such that each of the plurality of rotor blades has a leading edge which includes, in a meridional view, an oblique edge portion where a distance between the leading edge and an axis of the rotational shaft decreases from a tip side toward a hub side, and a sensor detection surface having a flat shape and being applied with a marking which is detectable by an optical sensor device. The sensor detection surface is formed on at least one of the circumferential surface of the hub or an edge portion of a reference rotor blade being one of the plurality of rotor blades, such that, in the meridional view, a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the sensor detection surface is smaller than a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the oblique edge portion.

A mixed-flow turbine wheel includes: a plurality of rotor blades disposed on a circumferential surface of the hub at intervals in a circumferential direction and configured such that each of the plurality of rotor blades has a leading edge which includes, in a meridional view, an oblique edge portion where a distance between the leading edge and an axis of the rotational shaft decreases from a tip side toward a hub side, and a sensor detection surface having a flat shape and being applied with a marking which is detectable by an optical sensor device. The sensor detection surface is formed on at least one of the circumferential surface of the hub or an edge portion of a reference rotor blade being one of the plurality of rotor blades, such that, in the meridional view, a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the sensor detection surface is smaller than a trailing-edge side angle of two angles formed between the axis of the rotational shaft and a normal of the oblique edge portion.

Provided are a device and a measuring method for measuring an unbalanced moment on a bottom surface of a circular valve core. The device includes a diverging shaped tube, a water tank, a transparent tube, spring dynamometers, laser sources, a circular valve core, and a high-speed camera with a camera stand. Inner shackles and the laser sources are evenly distributed on an outer side of the circular valve core of the device, the spring dynamometers are connected with the inner shackles and with the outer shackles evenly distributed on an inner wall of the transparent tube. The method records an unbalanced state of the circular valve core under an impact of water flow from different orientations with the high-speed camera on the camera stand, the location of the laser point on the outer wall and a tension force of the spring dynamometer are read to calculate a torque of the circular valve core.