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Real-Time Impact Visualization Inspection of Aerospace Composite Structures with Distributed Sensors.

Si L, Baier H - Sensors (Basel) (2015)

Bottom Line: With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole.The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions.Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

View Article: PubMed Central - PubMed

Affiliation: Institute of Lightweight Structures, Faculty of Mechanical Engineering, Technische Universität München, Boltzmannstr. 15, Garching 85748, Germany. l.si@tum.de.

ABSTRACT
For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

No MeSH data available.


Impact identifications on the cutout CFRP structure (Specimen 2). (a) Impact identification for event C1; (b) Impact identification for event C2.
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sensors-15-16536-f016: Impact identifications on the cutout CFRP structure (Specimen 2). (a) Impact identification for event C1; (b) Impact identification for event C2.

Mentions: (1) To validate the efficacy of the impact identification function, a series of impact tests were implemented on the various CFRP panel structures (Specimens 1 and 2). However, in order to reveal the impact identification performance of the IVI technique comprehensively, some impact events with representative impact locations are selected and illustrated in Figure 15 and Figure 16. For Specimen 1, impact event N1 is selected due to the consideration of boundary performance validation, and impact event N2 is selected with the consideration of general performance validation. As well, for Specimen 2, two impact events C1 and C2 which both occurred at surrounding positions close to the cutout hole of the structure were chosen. The impact event C1 occurred in the vicinity of the upper boundary of the structure’s discontinuity, and the impact event C2 occurred in the vicinity of the lower boundary of the structure’s discontinuity. The two impact events on a cutout structure were selected to verify the anti-discontinuity capability of the impact identification function due to the inhomogeneous property of the structure, typically, an airplane fuselage panel with a window cutout frame.


Real-Time Impact Visualization Inspection of Aerospace Composite Structures with Distributed Sensors.

Si L, Baier H - Sensors (Basel) (2015)

Impact identifications on the cutout CFRP structure (Specimen 2). (a) Impact identification for event C1; (b) Impact identification for event C2.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541892&req=5

sensors-15-16536-f016: Impact identifications on the cutout CFRP structure (Specimen 2). (a) Impact identification for event C1; (b) Impact identification for event C2.
Mentions: (1) To validate the efficacy of the impact identification function, a series of impact tests were implemented on the various CFRP panel structures (Specimens 1 and 2). However, in order to reveal the impact identification performance of the IVI technique comprehensively, some impact events with representative impact locations are selected and illustrated in Figure 15 and Figure 16. For Specimen 1, impact event N1 is selected due to the consideration of boundary performance validation, and impact event N2 is selected with the consideration of general performance validation. As well, for Specimen 2, two impact events C1 and C2 which both occurred at surrounding positions close to the cutout hole of the structure were chosen. The impact event C1 occurred in the vicinity of the upper boundary of the structure’s discontinuity, and the impact event C2 occurred in the vicinity of the lower boundary of the structure’s discontinuity. The two impact events on a cutout structure were selected to verify the anti-discontinuity capability of the impact identification function due to the inhomogeneous property of the structure, typically, an airplane fuselage panel with a window cutout frame.

Bottom Line: With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole.The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions.Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

View Article: PubMed Central - PubMed

Affiliation: Institute of Lightweight Structures, Faculty of Mechanical Engineering, Technische Universität München, Boltzmannstr. 15, Garching 85748, Germany. l.si@tum.de.

ABSTRACT
For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

No MeSH data available.