An AE-signal detecting device for an abrasive wheel includes: an AE sensor which outputs an AE signal upon receipt of an elastic wave generated in an annular abrasive wheel sandwiched between a fixed flange fixed to a rotating shaft and a movable flange provided capable of getting closer to/separating from the fixed flange; a transmission circuit portion which wirelessly transmits the AE signal output from the AE sensor; and a reception circuit portion which receives the AE signal transmitted wirelessly, wherein the AE sensor is disposed on the movable flange or the fixed flange, detects the elastic wave transmitted from the abrasive wheel, and outputs the AE signal.

The embodiments of the present disclosure may disclose a vibration sensor, including: an acoustic transducer and a vibration assembly connected with the acoustic transducer. The vibration assembly may be configured to transmit an external vibration signal to the acoustic transducer to generate an electric signal, the vibration assembly includes one or more groups of vibration diaphragms and mass blocks, and the mass blocks may be physically connected with the vibration diaphragms. The vibration assembly may be configured to make a sensitivity degree of the vibration sensor greater than a sensitivity degree of the acoustic transducer in one or more target frequency bands.

The embodiments of the present disclosure may disclose a vibration sensor, including: an acoustic transducer and a vibration assembly connected with the acoustic transducer. The vibration assembly may be configured to transmit an external vibration signal to the acoustic transducer to generate an electric signal, the vibration assembly includes one or more groups of vibration diaphragms and mass blocks, and the mass blocks may be physically connected with the vibration diaphragms. The vibration assembly may be configured to make a sensitivity degree of the vibration sensor greater than a sensitivity degree of the acoustic transducer in one or more target frequency bands.

A hydrophone used for measuring acoustic energy from a high frequency ultrasound transducer, or a method of manufacturing the membrane hydrophone. The membrane assembly is supported by the frame and comprises a piezoelectric. The hydrophone also includes an electrode pattern formed within the piezoelectric to define an active area. In addition, the hydrophone includes a built in-situ coaxial layer connected to the active area.

A hydrophone used for measuring acoustic energy from a high frequency ultrasound transducer, or a method of manufacturing the membrane hydrophone. The membrane assembly is supported by the frame and comprises a piezoelectric. The hydrophone also includes an electrode pattern formed within the piezoelectric to define an active area. In addition, the hydrophone includes a built in-situ coaxial layer connected to the active area.

An apparatus may include an ultrasonic sensor system having a first layer stack and a second layer stack. The first layer stack may include a first ultrasonic transmitter and the second layer stack may include a second ultrasonic transmitter. The first layer stack and/or the second layer stack may include an ultrasonic receiver. A frequency splitting layer may reside between the first layer stack and the second layer stack.

This application discloses example piezoelectric acoustic sensors and methods for manufacturing the piezoelectric acoustic sensor, and belongs to the field of electronic technologies. In one example, the piezoelectric acoustic sensor includes an anchoring unit, a piezoelectric unit, a support unit, and a hollow-out mechanical part. A back cavity is formed in the anchoring unit. The piezoelectric unit is configured to convert a sound signal that enters the back cavity into an electrical signal. The support unit covers the anchoring unit and the piezoelectric unit. The hollow-out mechanical part is connected between the anchoring unit and the piezoelectric unit, and is embedded in the support unit.

This application discloses example piezoelectric acoustic sensors and methods for manufacturing the piezoelectric acoustic sensor, and belongs to the field of electronic technologies. In one example, the piezoelectric acoustic sensor includes an anchoring unit, a piezoelectric unit, a support unit, and a hollow-out mechanical part. A back cavity is formed in the anchoring unit. The piezoelectric unit is configured to convert a sound signal that enters the back cavity into an electrical signal. The support unit covers the anchoring unit and the piezoelectric unit. The hollow-out mechanical part is connected between the anchoring unit and the piezoelectric unit, and is embedded in the support unit.

A method is provided for identifying or authenticating an object. The method includes vibrating the object at a plurality of frequencies. The vibrations from the object are sensed at each of the plurality of frequencies using an accelerometer. A vibration profile of the object is generated using the sensed vibrations. The generated vibration profile is then compared to a stored vibration profile. It is determined if the generated vibration profile matches the stored vibration profile. A match indicates that the object has been identified or authenticated. In another embodiment, an object capable of implementing the method is provided. In another embodiment, the object may include a replaceable accessary. In this case, the initial and generated vibration profiles may be created with the replacement accessary attached to the object. A match of the generated and initial vibration profiles indicates that the replaceable accessary is authentic.

A method is provided for identifying or authenticating an object. The method includes vibrating the object at a plurality of frequencies. The vibrations from the object are sensed at each of the plurality of frequencies using an accelerometer. A vibration profile of the object is generated using the sensed vibrations. The generated vibration profile is then compared to a stored vibration profile. It is determined if the generated vibration profile matches the stored vibration profile. A match indicates that the object has been identified or authenticated. In another embodiment, an object capable of implementing the method is provided. In another embodiment, the object may include a replaceable accessary. In this case, the initial and generated vibration profiles may be created with the replacement accessary attached to the object. A match of the generated and initial vibration profiles indicates that the replaceable accessary is authentic.