Abstract

Measuring the deformation of building elements engulfed by flames is essential in fire research to improve safety in the event of a fire. Ideally, the measurement system should be non-contact, able to range at the millimeter to meter scale with sub-mm precision, and have sufficient speed to capture temperature-induced deformations of the target object. To date, no ranging technology has been demonstrated that meets those requirements while imaging through flames. Here, we show that coherent laser detection and ranging (LADAR) can provide three-dimensional images of objects hidden behind methane or acetylene flames with sufficiently high precision to track their deformation. The heterodyne detection of coherent frequency-modulated continuous-wave (FMCW) LADAR allows the ranging signal to be detected in the presence of strong radiation of the flames. We measure three-dimensional point clouds of diffusely scattering complex surfaces with a precision of less than 30 μm at 2-meter stand-off distance, despite soot-induced signal loss and steering (refraction) of the ranging laser by the flames. Movies of the heat-induced surface deformation of objects illustrate the temporal performance. These data show that FMCW LADAR can quantify the deformation and movement of objects in fires, when non-contact shape measurements at stand-off distances of multiple meters are crucial.

© 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Full Article  |  PDF Article

Corrections

9 August 2018: A correction was made to supplementary material links.


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References

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2018 (1)

2017 (1)

2016 (2)

M. S. Hoehler and C. M. Smith, “Application of blue laser triangulation sensors for displacement measurement through fire,” Meas. Sci. Technol. 27, 115201 (2016).
[Crossref]

Z. Wang, B. Potsaid, L. Chen, C. Doerr, H.-C. Lee, T. Nielson, V. Jayaraman, A. E. Cable, E. Swanson, and J. G. Fujimoto, “Cubic meter volume optical coherence tomography,” Optica 3, 1496–1503 (2016).
[Crossref]

2014 (2)

2013 (2)

2012 (2)

G. Berkovic and E. Shafir, “Optical methods for distance and displacement measurements,” Adv. Opt. Photon. 4, 441–471 (2012).
[Crossref]

V. K. R. Kodur, M. Garlock, and N. Iwankiw, “Structures in fire: state-of-the-art, research and training needs,” Fire Technol. 48, 825–839 (2012).
[Crossref]

2009 (2)

P. A. Roos, R. R. Reibel, T. Berg, B. Kaylor, Z. W. Barber, and W. R. Babbitt, “Ultrabroadband optical chirp linearization for precision metrology applications,” Opt. Lett. 34, 3692–3694 (2009).
[Crossref]

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

2001 (1)

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

1995 (1)

L. W. Kostiuk and R. K. Cheng, “The coupling of conical wrinkled laminar flames with gravity,” Combust. Flame 103, 27–40 (1995).
[Crossref]

1988 (2)

Z. G. Habib and P. Vervisch, “On the refractive index of soot at flame temperature,” Combust. Sci. Technol. 59, 261–274 (1988).
[Crossref]

J. Buckmaster and N. Peters, “The infinite candle and its stability—a paradigm for flickering diffusion flames,” Symp. Combust. 21, 1829–1836 (1988).
[Crossref]

1987 (1)

Almand, K. H.

K. H. Almand, Structural Fire Resistance Experimental Research: Priority Needs of U.S. Industry (Springer, 2013).

Amann, M.-C.

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Babbitt, W. R.

Barber, Z. W.

Baumann, E.

Beitel, J.

J. Beitel, “Analysis of needs and existing capabilities for full-scale fire resistance testing,” (2008).

Berg, T.

Berkovic, G.

Bianco, V.

Bisby, L.

L. Bisby, J. Gales, and C. Maluk, “A contemporary review of large-scale non-standard structural fire testing,” Fire Sci. Rev. 2, 21–27 (2013).
[Crossref]

Bosch, T.

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Buckmaster, J.

J. Buckmaster and N. Peters, “The infinite candle and its stability—a paradigm for flickering diffusion flames,” Symp. Combust. 21, 1829–1836 (1988).
[Crossref]

Bundy, M.

T. McAllister, W. Luecke, M. Iadicola, and M. Bundy, “Measurement of Temperature, Displacement, and Strain in Structural Components Subject to Fire Effects: Concepts and Candidate Approaches,” in National Institute of Standards and Technology (2012).

Byer, R. L.

Cable, A. E.

Chen, L.

Cheng, R. K.

L. W. Kostiuk and R. K. Cheng, “The coupling of conical wrinkled laminar flames with gravity,” Combust. Flame 103, 27–40 (1995).
[Crossref]

Coddington, I.

Dagalakis, N.

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

Deschênes, J.-D.

DiLazaro, T.

Doerr, C.

Donaldson, A. B.

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

Faris, G. W.

Ferraro, P.

Finizio, A.

Fujimoto, J. G.

Gales, J.

L. Bisby, J. Gales, and C. Maluk, “A contemporary review of large-scale non-standard structural fire testing,” Fire Sci. Rev. 2, 21–27 (2013).
[Crossref]

Garlock, M.

V. K. R. Kodur, M. Garlock, and N. Iwankiw, “Structures in fire: state-of-the-art, research and training needs,” Fire Technol. 48, 825–839 (2012).
[Crossref]

Gill, W.

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

Giorgetta, F. R.

Glassman, I.

I. Glassman, R. A. Yetter, and N. G. Glumac, Combustion (Academic, 2014).

Glumac, N. G.

I. Glassman, R. A. Yetter, and N. G. Glumac, Combustion (Academic, 2014).

Gorman, J.

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

Grosshandler, W. L.

W. L. Grosshandler, “Fire Resistance Determination & Performance Prediction Research Needs Workshop: Proceedings,” (2002).

Habib, Z. G.

Z. G. Habib and P. Vervisch, “On the refractive index of soot at flame temperature,” Combust. Sci. Technol. 59, 261–274 (1988).
[Crossref]

Harding, K.

K. Harding, Handbook of Optical Dimensional Metrology (CRC Press, 2013).

Häusler, G.

Hoehler, M. S.

M. S. Hoehler and C. M. Smith, “Application of blue laser triangulation sensors for displacement measurement through fire,” Meas. Sci. Technol. 27, 115201 (2016).
[Crossref]

Iadicola, M.

T. McAllister, W. Luecke, M. Iadicola, and M. Bundy, “Measurement of Temperature, Displacement, and Strain in Structural Components Subject to Fire Effects: Concepts and Candidate Approaches,” in National Institute of Standards and Technology (2012).

Iwankiw, N.

V. K. R. Kodur, M. Garlock, and N. Iwankiw, “Structures in fire: state-of-the-art, research and training needs,” Fire Technol. 48, 825–839 (2012).
[Crossref]

Jayaraman, V.

Juberts, M.

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

Kaylor, B.

Kodur, V. K. R.

V. K. R. Kodur, M. Garlock, and N. Iwankiw, “Structures in fire: state-of-the-art, research and training needs,” Fire Technol. 48, 825–839 (2012).
[Crossref]

Kostiuk, L. W.

L. W. Kostiuk and R. K. Cheng, “The coupling of conical wrinkled laminar flames with gravity,” Combust. Flame 103, 27–40 (1995).
[Crossref]

Lee, H.-C.

Lescure, M.

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Locatelli, M.

Lucero, R. E.

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

Luecke, W.

T. McAllister, W. Luecke, M. Iadicola, and M. Bundy, “Measurement of Temperature, Displacement, and Strain in Structural Components Subject to Fire Effects: Concepts and Candidate Approaches,” in National Institute of Standards and Technology (2012).

Maluk, C.

L. Bisby, J. Gales, and C. Maluk, “A contemporary review of large-scale non-standard structural fire testing,” Fire Sci. Rev. 2, 21–27 (2013).
[Crossref]

McAllister, T.

T. McAllister, W. Luecke, M. Iadicola, and M. Bundy, “Measurement of Temperature, Displacement, and Strain in Structural Components Subject to Fire Effects: Concepts and Candidate Approaches,” in National Institute of Standards and Technology (2012).

Meucci, R.

Miccio, L.

Myllyla, R.

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Nehmetallah, G.

Newbury, N. R.

Nielson, T.

Paturzo, M.

Pelagotti, A.

Peters, N.

J. Buckmaster and N. Peters, “The infinite candle and its stability—a paradigm for flickering diffusion flames,” Symp. Combust. 21, 1829–1836 (1988).
[Crossref]

Poggi, P.

Potsaid, B.

Pugliese, E.

Reibel, R. R.

Rioux, M.

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Roos, P. A.

Shafir, E.

Smith, C. M.

M. S. Hoehler and C. M. Smith, “Application of blue laser triangulation sensors for displacement measurement through fire,” Meas. Sci. Technol. 27, 115201 (2016).
[Crossref]

Stone, J.

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

Stone, W. C.

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

Swann, W. C.

Swanson, E.

Vervisch, P.

Z. G. Habib and P. Vervisch, “On the refractive index of soot at flame temperature,” Combust. Sci. Technol. 59, 261–274 (1988).
[Crossref]

Wang, Z.

Willomitzer, F.

Yetter, R. A.

I. Glassman, R. A. Yetter, and N. G. Glumac, Combustion (Academic, 2014).

Yilmaz, N.

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

Adv. Opt. Photon. (1)

Combust. Flame (1)

L. W. Kostiuk and R. K. Cheng, “The coupling of conical wrinkled laminar flames with gravity,” Combust. Flame 103, 27–40 (1995).
[Crossref]

Combust. Sci. Technol. (1)

Z. G. Habib and P. Vervisch, “On the refractive index of soot at flame temperature,” Combust. Sci. Technol. 59, 261–274 (1988).
[Crossref]

Fire Sci. Rev. (1)

L. Bisby, J. Gales, and C. Maluk, “A contemporary review of large-scale non-standard structural fire testing,” Fire Sci. Rev. 2, 21–27 (2013).
[Crossref]

Fire Technol. (1)

V. K. R. Kodur, M. Garlock, and N. Iwankiw, “Structures in fire: state-of-the-art, research and training needs,” Fire Technol. 48, 825–839 (2012).
[Crossref]

J. Visualization (1)

N. Yilmaz, A. B. Donaldson, W. Gill, and R. E. Lucero, “Imaging of flame behavior in flickering methane/air diffusion flames,” J. Visualization 12(1), 47–55 (2009).
[Crossref]

Meas. Sci. Technol. (1)

M. S. Hoehler and C. M. Smith, “Application of blue laser triangulation sensors for displacement measurement through fire,” Meas. Sci. Technol. 27, 115201 (2016).
[Crossref]

Opt. Eng. (1)

M.-C. Amann, T. Bosch, M. Lescure, R. Myllyla, and M. Rioux, “Laser ranging: a critical review of usual techniques for distance measurement,” Opt. Eng. 40, 10–19 (2001).
[Crossref]

Opt. Express (4)

Opt. Lett. (3)

Optica (1)

Symp. Combust. (1)

J. Buckmaster and N. Peters, “The infinite candle and its stability—a paradigm for flickering diffusion flames,” Symp. Combust. 21, 1829–1836 (1988).
[Crossref]

Other (7)

W. L. Grosshandler, “Fire Resistance Determination & Performance Prediction Research Needs Workshop: Proceedings,” (2002).

J. Beitel, “Analysis of needs and existing capabilities for full-scale fire resistance testing,” (2008).

K. H. Almand, Structural Fire Resistance Experimental Research: Priority Needs of U.S. Industry (Springer, 2013).

T. McAllister, W. Luecke, M. Iadicola, and M. Bundy, “Measurement of Temperature, Displacement, and Strain in Structural Components Subject to Fire Effects: Concepts and Candidate Approaches,” in National Institute of Standards and Technology (2012).

K. Harding, Handbook of Optical Dimensional Metrology (CRC Press, 2013).

W. C. Stone, M. Juberts, N. Dagalakis, J. Stone, and J. Gorman, “Performance analysis of next-generation LADAR for manufacturing, construction, and mobility,” (2004).

I. Glassman, R. A. Yetter, and N. G. Glumac, Combustion (Academic, 2014).

Supplementary Material (5)

NameDescription
» 1: PDF (1520 KB)     
» Visualization 1       3D-Movie of a melting chocolate bar captured by an FMCW LADAR.
» Visualization 2       2D-Movie of a toy skeleton obstructed by a Methane flame.
» Visualization 3       2D-Movie of a melting chocolate bar.
» Visualization 4       3D-Movie of a melting chocolate bar captured by an FMCW LADAR.

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Figures (10)

Fig. 1.
Fig. 1. (a) Experimental ranging setup. A target obstructed by flames (depicted is an acetylene flame) is scanned with a FMCW LADAR. The target is placed 0.5    m behind this wall of flames. The total stand-off is 2 m. Range measurements are taken continuously at a 1-kHz update rate. A fast-steering mirror (FSM) sweeps the beam across the target, and the resulting 3D point cloud is then transformed to obtain Cartesian x y z points. (b)  x y z 3D point clouds. Left panel, machined aluminum step-block. Right panel, video (see Visualization 1) of a piece of chocolate, showing the deformation due to the flame heat (the frame rate is accelerated 60 × to 1 Hz).
Fig. 2.
Fig. 2. 3D images of the step-block. (a)  10 6 point cloud, corresponding to 16 min/frame, (b) 10,000 point cloud at 10 s/frame. Note that the mapped area on the step-block differs slightly.
Fig. 3.
Fig. 3. 3D x y z point cloud of the aluminum step-block where z is indicated in false color. A linear slope is removed from both images. (a) 3D image with no flame in the ranging path. (b) 3D image with block placed 0.5 m behind a 50 -mm-thick acetylene flame.
Fig. 4.
Fig. 4. (a) Video of methane flame and picture of a plastic skeleton, Visualization 2. (b) False-colored rendered 3D 1-million-point cloud of the plastic skeleton as mapped in 3D through the flame.
Fig. 5.
Fig. 5. (a) Sketch of ranging beam measuring melting chocolate through a methane flame. (b) Video (not through flame, Visualization 3) of melting chocolate bar. (c) LADAR video at a measured frame rate of 0.13 Hz (sped up to 10 Hz), Visualization 4.
Fig. 6.
Fig. 6. Effect of flame-induced beam deflection on ranging. (a) Schematic of beam deflection measurements through a methane flame as captured by an InGaAs focal plane array (FPA). To avoid FPA saturation by the flame, light outside the FMCW LADAR bandwidth is blocked by an optical band-pass filter (BPF) centered at 1560 nm. (b) Distribution of lateral beam-deflection in the x / y plane extracted from the FPA images. (c) 3.5-s-long example of range measurements to a diffusely scattering aluminum target through a methane flame. Data are shown for a flame without scanning (pink), for no flame without scanning (black), and for no flame but while applying an angular jitter via the FSM equivalent to that induced by the flame (gray). (d) Corresponding range distribution ( z direction).
Fig. 7.
Fig. 7. Ranging with fixed FSM position using the setup shown in Fig. 1(a) through a flame to an aluminum block at 2-m stand-off distance (the mean distance is subtracted from the plotted range). (a) Measured range and SNR of the range signal acquired through a methane flame that is ignited at 0 s and extinguished at 1100 s. There is a slow range drift of initially 85 nm/s, which is attributed to thermal expansion of the experimental setup. (b) Details showing the flame ignition (left panel) and extinction (right panel) events for both acetylene and methane flames. Traces in b) are smoothed with a 10-point binomial filter.
Fig. 8.
Fig. 8. (a) Power spectral density (PSD) of range measurements when ranging through an acetylene flame, a methane flame, and not through the flame, with the FSM held at a fixed position. The peak near 10 Hz is caused by flame flickering, and the peaks between 50 Hz and 60 Hz are caused by the FSM. (b) Ranging stability (overlapping modified Allan deviation) while ranging to the brushed aluminum target at 2-m stand-off and fixed position FSM. When there is no flame present (black), the stability averages down with 1 / t 1 / 2 , (black line) to 100 nm. The range stability deteriorates in the presence of a methane flame (pink) and even more so for an acetylene flame (yellow). While ranging through the flame, an overall slope was removed from the range measurements before calculating the modified Allan deviation.
Fig. 9.
Fig. 9. (a) Photo of setup to measure beam deflection through thick flames. (b) Extracted beam center pixel x position (the y position behaves very similarly and is not shown). The first 0.3-m burner is ignited at 12 s. At 103 s and 165 s, the second burner and third burner are ignited, increasing the flame width first to 0.6 m and finally to 0.9 m. (c) Blue trace, distribution of beam x position for beam deflection measurements between 12 s and 170 s. The distribution is calculated after removing a low-order polynomial baseline from the data in (b). Black, Gaussian fit. For comparison, the beam deflection distribution of the FMWC laser light traversing a 50 -mm methane flame is shown in pink.
Fig. 10.
Fig. 10. Tracking a moving object. (a) The block is placed on a lateral translation stage moving at constant velocity. The tracked step is circled in red, and the scanning pattern is sketched in green. (b) Extracted x location of the step as a function of measurement time. Also shown are a linear fit and residuals.

Tables (1)

Tables Icon

Table 1. Ranging Precision from Cross Sections Taken from x y z 3D Point Clouds of the Step-Block, While Ranging Through Methane or Acetylene Flames