A device and a method for ultrasonic detecting a mechanical member based on magnetic fluid coupling. The device comprises a magnetic field generating apparatus, magnetic fluid and an ultrasonic probe. The magnetic field generating apparatus has a cylindrical structure, into which the magnetic fluid is injected, where an upper portion of the apparatus is provided with the ultrasonic probe a front end that vertically extends into a liquid level of the magnetic fluid, and a bottom portion of the apparatus covers a detected position of a member under detection. The magnetic fluid at least contains magnetic suspension particles and oil-based or water-based liquid. With the device and the method, the ultrasonic probe is coupled with the member under detection to realize ultrasonic detecting of the service stress of the member under detection.

The present disclosure relates to the technical field of non-destructive detecting of residual stress, and in particular to a non-destructive detecting device for component residual stress gradient. the non-destructive detecting device comprises: groups of transmitting transducers and receiving transducers arranged symmetrically to each other, the transmitting transducers closer to the symmetry axis have greater excitation frequencies; an acoustic wedge coupled to the groups of transmitting transducers and receiving transducers, wherein groups of cylindrical transmitting tunnels and receiving tunnels are provided obliquely within the transmitting connection area and the receiving connection area through their top surfaces and toward their bottom surfaces, the transmitting transducers are coupled to the transmitting tunnels in a one-to-one correspondence, the receiving transducers are coupled to the receiving tunnels in a one-to-one correspondence, and the bottom surfaces of the transmitting connection area and the receiving connection area are pressed against the surface of the detected component; and a calculation processing module electrically connected to the transmitting transducers and the receiving transducers. The non-destructive detecting device solves the problem that the residual stress values of components at different penetration depths cannot be detected at the same time.

Disclosed is an acoustic sensor including: a component having an input and an output, the component being able to conduct light waves in a plurality of propagation modes between the input and the output, the component converting an acoustic signal to be measured into a phase shift proportional to an intermodal interference between at least two propagation modes, and a detector of a physical quantity dependent on the phase shift.

A method of measurement of the acting forces and/or the temperature in at least one region of a structure. The method includes an addition step in which at least one element is added to the structure, the addition generating a local vibration mode of the assembly formed by the structure and the added elements in each measurement region. The method also includes a step of analysis of the assembly, an excitation step of the assembly and a measurement step in which the variations produced in the resonance frequency of the assembly associated with the local vibration mode of each measurement region are measured. The method also includes a calculation step in which the acting forces and/or the temperature of the structure in the measurement region is determined based on the measured variation produced in the resonance frequency associated with the local vibration mode.

A device and a method for ultrasonic detecting a mechanical member based on magnetic fluid coupling. The device comprises a magnetic field generating apparatus, magnetic fluid and an ultrasonic probe. The magnetic field generating apparatus has a cylindrical structure, into which the magnetic fluid is injected, where an upper portion of the apparatus is provided with the ultrasonic probe a front end that vertically extends into a liquid level of the magnetic fluid, and a bottom portion of the apparatus covers a detected position of a member under detection. The magnetic fluid at least contains magnetic suspension particles and oil-based or water-based liquid. With the device and the method, the ultrasonic probe is coupled with the member under detection to realize ultrasonic detecting of the service stress of the member under detection.

A compound sensor that is capable of being used with robotics is provided such that the compound sensor includes a distance measurement unit and a pressure measurement unit. Further, a contact detection unit, which is dedicated to performing a detection when a measurement target contacts with a surface of the sensor is included.

A system, probe and method accurately measure the strain or extension of a fastener that occurs as a nut on the fastener is tightened and the fastener is put under load. The measurement technique is based on measurement of the time for an ultrasonic wave generated on one end of the fastener to travel a round trip through the fastener. As the fastener is tightened, the applied stress causes an associated increase in length. This length can be determined from a measurement of the increase in transit time. In various embodiments, the disclosed device and method uses laser ultrasonic testing (LUT), in which a pulsed laser generates the ultrasonic wave and a type of laser vibrometer detects the wave when it returns to the position of generation following a combination of longitudinal and shear wave reflections, which result in a higher magnitude and more easily and precisely measurable reflected signal peak than a signal peak associated with a signal directly reflected against the opposite end of the fastener.

There is provided a method for measuring a contact force applied to each tube constituting a tube bundle disposed in a fluid from a vibration damping member by using a probe inserted into each tube. Characteristic data defining a relationship between a value measured by the probe and the contact force is previously prepared. Then, the probe is inserted into the tube, and the contact force is calculated using the measurement value of the probe, based on the characteristic data.

A rock breaking device and a method of monitoring a condition of a tool of a rock breaking device is provided. The rock breaking device includes a frame, a tool, a device for generating stress waves in the tool, measuring means for measuring the stress wave propagating in the tool and at least one computing unit for monitoring a condition of the tool on the basis of the measured stress wave. The at least one computing unit is configured to determine a condition of the tool on the basis of a time of propagation of at least one reflected stress wave component of the stress wave and at least one additional property of the same reflected stress wave component.

An ultrasonic testing device and method for the connection force of interference fit. The motion control module can realize accurate positioning for the interference fit part and accurate control for motion in the circumferential direction and the axial direction; scanning increments of the circumferential direction and the axial direction are set, and the motion control module drives the interference fit part to perform circumferential and axial point scanning until the testing of the whole matching surface is completed. The ultrasonic signal measured by the point focusing water immersion probe is transmitted to a PC through a control loop in the testing process. Then the stress distribution of the matching surface is obtained through the relationship between the ultrasonic signal and contact stress Finally, the size of the connection force is calculated according to the static friction coefficient.