Article Article
Non-Contact Strain-Sensing Smart Skin

Structural health monitoring relies on routine inspection and maintenance to ensure safe operation and optimized service life of critical structures. Surface strain measurements can provide an important indicator of structural condition. Established strain sensor technologies, such as resistance strain gages and fiber Bragg grating (FBG) sensors, as well as some newer ones, [1–3] are all point-wise, unidirectional, and contact sensing methods that require physical connections in order to obtain strain readings. Some existing full-field non-contact optical methods have also been developed, such as interferometric techniques,[4] non-interferometric techniques,[5–7] and Raman spectroscopy.[8] The interferometric techniques usually require a model of actual structure, plus tedious calculations to separate the values of principal stresses, and expensive equipment. The limitation of non-interferometric techniques lies in the requirements for a random gray intensity distribution or speckle pattern distribution and heavy dependence on the quality of the imaging system. Over the past twenty years, Raman spectroscopy has also been investigated for strain sensing applications by many researchers.[8– 12] However, Raman-based strain sensing methods are hampered by the low intensity of Raman scattering signals. A more promising approach for non-contact strain sensing technology uses carbon nanotube fluorescence.

References

[1] Yong Y. A novel piezoelectric strain sensor for simultaneous damping and tracking control of a highspeed

nanopositioner. IEEE/ASME Transactions, (2013) 18(3), 1113–1121.

[2] Azevedo RG, Jones DG, Jog A V, et al. A SiC MEMS Resonant Strain Sensor for Harsh Environment

Applications. IEEE Sensors Journal, (2007) 7(4), 568–576.

[3] Dharap P, Li Z, Nagarajaiah S, Barrera E V. Nanotube film based on single-wall carbon nanotubes for

strain sensing. Nanotechnology, (2004) 15(3), 379–382.

[4] Ajovalasit A, Petrucci G, Scafidi M. RGB photoelasticity: review and improvements. Strain, (2010)

46(2), 137–147.

[5] Goldrein H, Palmer S, Huntley J. Automated fine grid technique for measurement of large-strain

deformation maps. Optics and Lasers in Engineering, (1995) 23(195), 305–318.

[6] Pan B. Full-field strain measurement using a two-dimensional Savitzky-Golay digital differentiator in

digital image correlation. Optical Engineering, (2007) 46(3), 033601.

[7] Hamada S, Fujisawa T, Koyama M, Koga N, Nakada N, Tsuchiyama T, Ueda M, Noguchi H. Strain

mapping with high spatial resolution across a wide observation range by digital image correlation on

plastic replicas. Materials Characterization, (2014) 98, 140–146.

[8] Zhao Q, Frogley MD, Wagner HD. Direction-sensitive strain-mapping with carbon nanotube sensors.

Composites Science and Technology, (2002) 62(1), 147–150.

[9] Li Z, Dharap P, Nagarajaiah S, Barrera EV, Kim JD. Carbon Nanotube Film Sensors. Advanced

Materials, (2004) 16(7), 640–643.

[10] Mu M, Osswald S, Gogotsi Y, Winey KI. An in situ Raman spectroscopy study of stress transfer

between carbon nanotubes and polymer. Nanotechnology, (2009) 20(33), 335703.

[11] de la Vega A, Kinloch IA, Young RJ, Bauhofer W, Schulte K. Simultaneous global and local strain

sensing in SWCNT–epoxy composites by Raman and impedance spectroscopy. Composites Science and

Technology, (2011) 71(2), 160–166.

[12] Raju APA, Lewis A, Derby B, Young RJ, Kinloch I a., Zan R, Novoselov KS. Wide-Area Strain Sensors

based upon Graphene-Polymer Composite Coatings Probed by Raman Spectroscopy. Advanced

Functional Materials, (2014) 24(19), 2865–2874.

[13] Nagarajaiah S, Weisman RB, Sun P, Bachilo SM, Yang Y. Strain-sensing smart skin: A noncontact

optical strain sensor using single-walled carbon nanotubes. In: Loh KJ, Nagarajaiah S, editors.

Innovative Developments of Advanced Multifunctional Nanocomposites in Civil and Structural

Engineering. Oxford: Woodhead Publishing; 2016. p. 353–375.

[14] Reich S, Thomsen C, Maultzsch J. Carbon nanotubes: basic concepts and physical properties. John

Wiley & Sons; 2008.

[15] O’Connell MJ, Bachilo SM, Huffman CB, et al. Band gap fluorescence from individual single-walled

carbon nanotubes. Science, (2002) 297(5581), 593–596.

[16] Weisman R, Bachilo S. Dependence of optical transition energies on structure for single-walled carbon

nanotubes in aqueous suspension: an empirical Kataura plot. Nano Letters, (2003) 3(9), 1235–1238.

[17] Yang L, Han J. Electronic structure of deformed carbon nanotubes. Physical Review Letters, (2000)

85(1), 154–157.

[18] Minot ED, Yaish Y, Sazonova V, Park J-Y, Brink M, McEuen PL. Tuning carbon nanotube band gaps

with strain. Physical review letters, (2003) 90(April), 156401.

[19] Li L-J, Nicholas RJ, Deacon RS, Shields P a. Chirality Assignment of Single-Walled Carbon Nanotubes

with Strain. Physical Review Letters, (2004) 93(October), 6–9.

[20] Maki H, Sato T, Ishibashi K. Direct observation of the deformation and the band gap change from an

individual single-walled carbon nanotube under uniaxial strain. Nano Letters, (2007) 7, 890–895.

[21] Leeuw TK, Tsyboulski D a, Nikolaev PN, Bachilo SM, Arepalli S, Weisman RB. Strain measurements

on individual single-walled carbon nanotubes in a polymer host: structure-dependent spectral shifts and

load transfer. Nano letters, (2008) 8(3), 826–831.

[22] Huang M, Wu Y, Chandra B, Yan H, Shan Y, Heinz TF, Hone J. Direct measurement of strain-induced

changes in the band structure of carbon nanotubes. Physical Review Letters, (2008) 100(April), 1–4.

[23] Valavala PK, Banyai D, Seel M, Pati R. Self-consistent calculations of strain-induced band gap changes

in semiconducting (n,0) carbon nanotubes. Physical Review B - Condensed Matter and Materials

Physics, (2008) 78, 1–6.

[24] Withey PA, Vemuru VSM, Bachilo SM, Nagarajaiah S, Weisman RB. Strain paint: noncontact strain

measurement using single-walled carbon nanotube composite coatings. Nano letters, (2012) 12(7),

3497–3500.

[25] Sun P, Kim J-H, Bachilo SM, Weisman RB, Nagarajaiah S. “Smart Skin” optical strain sensor using

single wall carbon nanotubes. In: SPIE Smart Structures and Materials+ Nondestructive Evaluation and

Health Monitoring. 2014. p. 906120.

[26] Sun P, Bachilo SM, Weisman RB, Nagarajaiah S. Carbon nanotubes as non-contact optical strain sensors

in smart skins. The Journal of Strain Analysis for Engineering Design, (2015) , 1–8.

[27] Sun P, Bachilo SM, Nagarajaiah S, Weisman RB. Toward Practical Non-Contact Optical Strain Sensing

Using Single-Walled Carbon Nanotubes. ECS Journal of Solid State Science and Technology, (2016)

5(8), M3012–M3017.

Metrics
Usage Shares
Total Views
134 Page Views
Total Shares
0 Tweets
134
0 PDF Downloads
0
0 Facebook Shares
Total Usage
134