Patent•
Positioning method for acoustic emission structure based on barycentric coordinates
25 Dec 2018-
TL;DR: In this paper, a damage positioning method for an acoustic emission structure based on barycentric coordinates is proposed, which consists of the following steps of: obtaining an acousticemission signal by performing an impact test on a material in advance, using a first peak point of a waveform of an acoustic emissions wave as an arrival time t of the acoustic emission signal; obtaining velocity distribution rule of the emission wave in the whole structure by measuring a distance and the arrival time T from a detected structure damage point to a sensor; arranging three sensors above the structure; collecting an acoustic signal of
Abstract: The invention discloses a damage positioning method for an acoustic emission structure based on barycentric coordinates. The positioning method comprises the following steps of: obtaining an acousticemission signal by performing an impact test on a material in advance; using a first peak point of a waveform of an acoustic emission wave as an arrival time t of the acoustic emission signal; obtaining velocity distribution rule of the acoustic emission wave in the whole structure by measuring a distance and the arrival time t from a detected structure damage point to a sensor; arranging three sensors above the structure; collecting an acoustic emission signal of an unknown point; obtaining an arrival time of the acoustic emission signal of the unknown point; reusing the velocity distributionrule of the acoustic emission wave and the arrival time of the acoustic emission signal to obtain distances from the acoustic emission wave to the three sensors; and substituting the distances into the barycentric positioning algorithm program so as to obtain the two-dimensional plane coordinates of the structural damage points. According to the positioning method for the acoustic emission structure damage based on the barycentric coordinates, the position of the damage point in the structure can be accurately calculated without being restricted by the position of the sensor, and the requirement of the real environment condition can be better satisfied.
References
More filters
Patent•
20 Jul 2011
TL;DR: In this article, a method for positioning a micro seismic source or an acoustic emission source, which comprises the following steps of placing a plurality of acoustic emission transducers nearby an object to be detected, and solving position coordinates of the micro seismic sources or the acoustic emission sources by using a nonlinear least square regression method, such as a simplex acceleration method or a Marquardt method or the like, according to the coordinate values and the time difference of the positions of the known transducers and according to a distance operational formula.
Abstract: The invention discloses a method for positioning a micro seismic source or an acoustic emission source, which comprises the following steps of: placing a plurality of acoustic emission transducers nearby an object to be detected, and solving position coordinates of the micro seismic source or the acoustic emission source by using a nonlinear least square regression method, such as a simplex acceleration method or a Marquardt method or the like, according to the coordinate values and the time difference of the positions of the known transducers and according to a distance operational formula. The acoustic emission positioning method disclosed by the invention does not need to measure or preset acoustic velocity, can avoid the influence of acoustic velocity measurement on positioning, improves the positioning precision, and is convenient and practical in practical engineering application compared with a traditional method.
34 citations
Patent•
20 Feb 2013
11 citations
TL;DR: It was proposed that the barycentric coordinate-based localization algorithm can be used to predict the coordinates of the AE source and the experimental results show that the proposed method is feasible.
Abstract: Structures and machines are very susceptible to some barely visible defects; acoustic emission (AE) is an effective technique of detecting defects and examining growth and location of these defects. In this paper, a new method was proposed to predict the position of the AE source. The dynamic strain signal from the AE source was acquired by fiber Bragg grating (FBG) sensors. Complex Morlet wavelet transform was used to extract narrowband signals from AE waves. It was proposed that the barycentric coordinate-based localization algorithm can be used to predict the coordinates of the AE source. The validation tests based on the designed AE detection system were performed on a 500 mm × 500 mm × 2 mm Al-alloy plate. The experimental results show that the proposed method is feasible.
11 citations
Patent•
17 Feb 2016
TL;DR: In this paper, a rock acoustic emission source positioning method is presented, where the acoustic emission sensors are placed on the periphery of the cuboid sample, and vaseline is smeared between the sensors and the sample.
Abstract: The invention discloses a rock acoustic emission source positioning method and belongs to the technical field of rock acoustic emission source positioning. According to the method, a granite standard cuboid sample is prepared; N acoustic emission sensors not located on the same plane are placed on the periphery of the cuboid sample, and vaseline is smeared between the sensors and the sample; the acoustic emission sensors are used for receiving acoustic emission signals generated inside the sample due to damage; acoustic emission waveforms received by all the acoustic emission sensors are subjected to wavelet denoising processing and wavelet decomposition; four different sensors and four sub-band signals with the same dominant frequency are selected according to the signals received from the sensors; the four sub-band signals are subjected to all-phase spectral analysis, phases of the four sub-band signals are obtained respectively, time difference measurement is conducted through a phase difference method, and the time difference between the acoustic emission signals received by the four sensors is obtained. Coordinates of an acoustic emission source K are obtained by means of acoustic emission space positioning by the adoption of a least square method according to position coordinates of the four sensors through the time difference, determined in the sixth step, between the acoustic emission signals received by the four sensors.
10 citations
Patent•
16 Nov 2016
TL;DR: In this article, a glass fiber reinforced plastic acoustic emission source triangulation location method is proposed. But the method is not suitable for the acoustic emission detection mode of the composite material of glass fiber-reinforced plastic.
Abstract: The invention discloses a glass fiber reinforced plastic acoustic emission source triangulation location method. According to the technical scheme, the method comprises the steps that 1, to-be-measured glass fiber reinforced plastic angle-speed polynomial is subjected to fitting; 2, sensor probes are arranged on a glass fiber reinforced plastic tank to be measured according to an isosceles triangle arrangement method; 3, coordinates of three vertexes of an isosceles triangle are set; 4, location results are obtained through operation. The glass fiber reinforced plastic acoustic emission source triangulation location method has the advantages that the problem that for the acoustic emission detection mode of the composite material of glass fiber reinforced plastic, the propagation speeds in different directions are different due to material anisotropy, and a location error is big is solved; the whole method is simple and easy to operate, and complex artificial operation can be replaced by means of curve fitting in an Excel table; the final measurement results are accurate.
9 citations