Impact source localisation in aerospace composite structures

The most commonly encountered type of damage in aircraft composite structures is caused by low-velocity impacts due to foreign objects such as hail stones, tool drops and bird strikes. Often these events can cause severe internal material damage that is difficult to detect and may lead to a significant reduction of the structure’s strength and fatigue life. For this reason there is an urgent need to develop structural health monitoring systems able to localise low-velocity impacts in both metallic and composite components as they occur. This article proposes a novel monitoring system for impact localisation in aluminium and composite structures, which is able to determine the impact location in real-time without a-priori knowledge of the mechanical properties of the material. This method relies on an optimal configuration of receiving sensors, which allows linearization of well-known nonlinear systems of equations for the estimation of the impact location. The proposed algorithm is based on the time of arrival identification of the elastic waves generated by the impact source using the Akaike Information Criterion. The proposed approach was demonstrated successfully on both isotropic and orthotropic materials by using a network of closely spaced surface-bonded piezoelectric transducers. The results obtained show the validity of the proposed algorithm, since the impact sources were detected with a high level of accuracy. The proposed impact detection system overcomes current limitations of other methods and can be retrofitted easily on existing aerospace structures allowing timely detection of an impact event.

[1]  Francesco Ciampa,et al.  Acoustic emission source localization and velocity determination of the fundamental mode A0 using wavelet analysis and a Newton-based optimization technique , 2010 .

[2]  H. Akaike.  A new look at the statistical model identification , 1974 .

[3]  F. Boschetti,et al.  A fractal-based algorithm for detecting first arrivals on seismic traces , 1996 .

[4]  Igor Grabec,et al.  Intelligent location of simultaneously active acoustic emission sources: Part I , 2003, ArXiv.

[5]  Giuseppe Lacidogna,et al.  Reliable onset time determination and source location of acoustic emissions in concrete structures , 2012 .

[6]  Francesco Ciampa,et al.  Factors affecting the imaging of the impact location with inverse filtering and diffuse wave fields , 2016 .

[7]  Manfred Baer,et al.  An automatic phase picker for local and teleseismic events , 1987 .

[8]  Jochen H Kurz,et al.  Strategies for reliable automatic onset time picking of acoustic emissions and of ultrasound signals in concrete. , 2005, Ultrasonics.

[9]  H. Akaike.  Markovian representation of stochastic processes and its application to the analysis of autoregressive moving average processes , 1974 .

[10]  Fu-Kuo Chang,et al.  Impact identification of stiffened composite panels: I. System development , 2001 .

[11]  Dayong Hu,et al.  Near-field beamforming analysis for acoustic emission source localization. , 2012, Ultrasonics.

[12]  F. Chang,et al.  Impact identification of stiffened composite panels: II. Implementation studies , 2001 .

[13]  Petr Sedlák,et al.  Acoustic emission localization in thin multi-layer plates using first-arrival determination , 2013 .

[14]  Yoshihiro Mizutani,et al.  REAL-TIME EXECUTING SOURCE LOCATION SYSTEM APPLICABLE TO ANISOTROPIC THIN STRUCTURES , 2005 .

[15]  A. Douglas,et al.  Bandpass filtering to reduce noise on seismograms: Is there a better way? , 1997, Bulletin of the Seismological Society of America.

[16]  Jie Xu,et al.  P-Wave Onset Detection Based on the Spectrograms of the AE Signals , 2011 .

[17]  Genshiro Kitagawa,et al.  A procedure for the modeling of non-stationary time series , 1978 .

[18]  Reinoud Sleeman,et al.  Robust automatic P-phase picking: an on-line implementation in the analysis of broadband seismogram recordings , 1999 .

[19]  Francesco Ciampa,et al.  A new algorithm for acoustic emission localization and flexural group velocity determination in anisotropic structures , 2010 .

[20]  T. Kundu,et al.  Locating Point of Impact on an Anisotropic Cylindrical Surface Using Acoustic Beamforming Technique , 2013 .

[21]  H. Akaike,et al.  Information Theory and an Extension of the Maximum Likelihood Principle , 1973 .

[22]  Steven D. Glaser,et al.  Beamforming array techniques for acoustic emission monitoring of large concrete structures , 2010 .

[23]  T. Kundu,et al.  Locating point of impact in anisotropic fiber reinforced composite plates. , 2008, Ultrasonics.

[24]  Robert E. Seydel.  Impact identification of stiffened composite panels , 2000 .

[25]  Francesco Ciampa,et al.  Impact localization on a composite tail rotor blade using an inverse filtering approach , 2014 .

[26]  N. Maeda.  A Method for Reading and Checking Phase Time in Auto-Processing System of Seismic Wave Data , 1985 .

[27]  Clifford H. Thurber,et al.  Automatic P-Wave Arrival Detection and Picking with Multiscale Wavelet Analysis for Single-Component Recordings , 2003 .

[28]  R. V. Allen,et al.  Automatic phase pickers: Their present use and future prospects , 1982 .

[29]  T. Kundu,et al.  Point of impact prediction in isotropic and anisotropic plates from the acoustic emission data. , 2007, The Journal of the Acoustical Society of America.

[30]  T. Kundu,et al.  Acoustic source localization in anisotropic plates. , 2012, Ultrasonics.

[31]  Josef Sikula,et al.  New automatic localization technique of acoustic emission signals in thin metal plates. , 2009, Ultrasonics.

[32]  M. Gorman,et al.  Source location in thin plates using cross-correlation , 1991 .

[33]  A. Tobias,et al.  Acoustic-emission source location in two dimensions by an array of three sensors , 1976 .

[34]  M. Leonard,et al.  Multi-component autoregressive techniques for the analysis of seismograms , 1999 .

[35]  B. Kennett,et al.  Automatic seismic event recognition and later phase identification for broadband seismograms , 1996, Bulletin of the Seismological Society of America.

[36]  Tribikram Kundu,et al.  A new technique for acoustic source localization in an anisotropic plate without knowing its material properties , 2012 .

[37]  Michele Meo,et al.  Impact identification on a sandwich plate from wave propagation responses , 2005 .

[38]  D. Hinkley.  Inference about the change-point from cumulative sum tests , 1971 .

[39]  Giuseppe Lacidogna,et al.  Onset time determination of acoustic and electromagnetic emission during rock fracture , 2012 .

[40]  Ettore Barbieri,et al.  Impact localization in composite structures of arbitrary cross section , 2012 .

[41]  Colin MacBeth,et al.  The application of back‐propagation neural network to automatic picking seismic arrivals from single‐component recordings , 1997 .