Optical fiber profiler for early damage warning

Abstract

To provide an exemplary device, method, and computer program product for detecting a change (e.g., deformation) in a surface using an optical fiber.SOLUTION: The exemplary device can include an optical fiber 102 having a first end and a second end, wherein the optical fiber is positioned in a two-dimensional pattern on a surface. An illumination source 104 is positioned at the first end of the optical fiber and is configured to emit a light output into the first end of the optical fiber. A first optical receiver 106 is also positioned at the first end of the optical fiber, an is configured to receive reflected light. The device can include a second optical receiver 108 configured to receive transmitted light at the second end of the optical fiber. A change in the surface is detected on the basis of at least in part on the reflected light and the transmitted light.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to detecting deformations on a surface, and more particularly to detecting deformations on a surface using optical fibers to provide early warning of damage to the surface. [Background technology]

[0002] Applicant has identified many technical challenges and difficulties associated with using optical fibers to detect deformations on surfaces. Through applied effort, ingenuity, and innovation, Applicant has solved the problems associated with detecting deformations on surfaces using optical fibers by developing the solutions embodied in this disclosure, which are described in detail below. Summary of the Invention

[0003] Various embodiments are directed to exemplary devices, methods, and computer program products for detecting changes (e.g., deformations) in a surface using an optical fiber. An exemplary device is provided. In some embodiments, the exemplary device can include an optical fiber having a first end and a second end, the optical fiber being positioned on the surface. The device can further include an illumination source configured to emit a light output into the first end of the optical fiber. The device can further include a first optical receiver configured to receive reflected light at the first end of the optical fiber. Additionally, in some embodiments, the device can include a second optical receiver configured to receive transmitted light at the second end of the optical fiber. The change in the surface is detected based at least in part on the reflected light and the transmitted light.

[0004] In some embodiments, the optical fibers are disposed in a two-dimensional pattern on the surface.

[0005] In some embodiments, the two-dimensional location of the surface alteration is determined.

[0006] In some embodiments, the first receiver is configured to determine a backscatter pattern and the second receiver is configured to determine a forward scatter pattern.

[0007] In some embodiments, the two-dimensional location of the surface alteration is determined based on the time difference between the backscattering pattern change and the forward scattering pattern change.

[0008] In some embodiments, the change to the surface is a deformation of the surface.

[0009] In some embodiments, the magnitude of the deformation of the surface is determined based at least in part on at least one of the transmitted light and the reflected light.

[0010] In some embodiments, a three-dimensional model of the surface is generated based at least in part on the transmitted and reflected light.

[0011] In some embodiments, the three-dimensional model includes two-dimensional locations of the surface changes and magnitudes of the surface changes.

[0012] In some embodiments, the surface comprises at least a portion of a battery housing.

[0013] In some embodiments, the unsafe battery condition is determined based at least in part on the changes in the surface.

[0014] In some embodiments, the illumination source is a laser diode configured to emit laser pulses.

[0015] Exemplary methods are also provided. In some embodiments, the exemplary method may include transmitting, by an illumination source, an optical output into a first end of an optical fiber, the optical fiber being positioned on the surface. The exemplary method may further include receiving the reflected light at a first optical receiver positioned at the first end of the optical fiber. In some embodiments, the exemplary method may include receiving the transmitted light at a second optical receiver positioned at a second end of the optical fiber, and detecting a change in the surface based at least in part on the reflected light and the transmitted light.

[0016] In some embodiments, the optical fibers are disposed in a two-dimensional pattern on the surface.

[0017] In some embodiments, the exemplary method further includes determining a two-dimensional location of the surface alteration.

[0018] In some embodiments, the exemplary method may further include receiving the backscatter pattern at a first receiver and receiving the forward scatter pattern at a second receiver.

[0019] In some embodiments, determining the two-dimensional location of the surface alteration further comprises determining a time difference between the backscattering pattern change and the forward scattering pattern change.

[0020] In some embodiments, the surface comprises at least a portion of a battery housing.

[0021] In some embodiments, the method may further include determining an unsafe battery condition based at least in part on the change in the surface.

[0022] A computer program product for detecting changes in a surface is also provided. In some embodiments, the computer program product may comprise at least one non-transitory computer readable storage medium having computer readable program code portions stored thereon, the computer readable program code portions comprising an executable portion configured to cause an illumination source to transmit an optical output into a first end of an optical fiber, the optical fiber being positioned on the surface. In some embodiments, the executable portion may be further configured to receive a reflected photoelectrical signal representative of the reflected light received at a first optical receiver positioned at the first end of the optical fiber. The executable portion may be further configured to receive a transmitted photoelectrical signal representative of the transmitted light received at a second optical receiver positioned at a second end of the optical fiber. The executable portion may be further configured to detect changes in the surface based at least in part on the reflected photoelectrical signal and the transmitted photoelectrical signal. [Brief description of the drawings]

[0023] Reference will now be made to the accompanying drawings, in which components illustrated in the figures may or may not be present in a particular embodiment described herein. Some embodiments may include fewer (or more) components than those shown in the figures according to exemplary embodiments of the present disclosure. [Figure 1] FIG. 1 illustrates an example block diagram of an example optical fiber profiler according to an example embodiment of the present disclosure. [Diagram 2] 1 illustrates an exemplary embodiment of a fiber optic profiler on a surface, according to an exemplary embodiment of the present disclosure. [Figure 3A] 1 illustrates an exemplary battery housing tray and an exploded view of an exemplary battery housing tray including a fiber optic pattern, according to an exemplary embodiment of the present disclosure; [Figure 3B] 1 illustrates an exemplary battery housing tray and an exploded view of an exemplary battery housing tray including a fiber optic pattern, according to an exemplary embodiment of the present disclosure; [Figure 4A]1 illustrates an exemplary battery housing and an exploded view of the exemplary battery housing including a fiber optic pattern, according to an exemplary embodiment of the present disclosure; [Figure 4B] 1 illustrates an exemplary battery housing and an exploded view of the exemplary battery housing including a fiber optic pattern, according to an exemplary embodiment of the present disclosure; [Figure 5A] 1 illustrates an exemplary battery housing and a cross-sectional view of the exemplary battery housing, according to an exemplary embodiment of the present disclosure; [Figure 5B] 1 illustrates an exemplary battery housing and a cross-sectional view of the exemplary battery housing, according to an exemplary embodiment of the present disclosure; [Figure 6] 1 illustrates a close-up view of a cross section of an exemplary battery housing, according to an exemplary embodiment of the present disclosure. [Figure 7] 1 illustrates an exemplary embodiment of an optical fiber pattern according to an exemplary embodiment of the present disclosure. [Figure 8] 1 illustrates an example block diagram of an example sensing interferometer used in accordance with an example embodiment of the present disclosure. [Figure 9] FIG. 2 illustrates an example block diagram of computational components of an example controller, according to an example embodiment of the present disclosure. [Figure 10] 1 illustrates an exemplary three-dimensional model of a surface generated in accordance with an exemplary embodiment of the present disclosure. [Figure 11] 1 illustrates a flow diagram of an exemplary method for detecting changes in a surface, according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Exemplary embodiments are described in more detail below with reference to the accompanying drawings, in which some, but not all, embodiments of the invention of this disclosure are shown. Indeed, embodiments of the present disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

[0025] Various exemplary embodiments address technical problems associated with detecting surface changes and / or deformations using optical fibers. As will be appreciated by those skilled in the art to which this disclosure pertains, there are numerous exemplary scenarios in which detecting surface changes using optical fibers may be useful. For example, deformation of one or more surfaces of a battery housing may be indicative of a dangerous battery condition, such as thermal runaway.

[0026] Generally, batteries (e.g., lithium ion batteries, lithium polymer batteries, etc.) can provide power to various devices through chemical reactions within the battery cells. Devices that require significant amounts of power, such as electric vehicles, may include tens, hundreds, or even thousands of battery cells within a battery housing.

[0027] In certain circumstances, the movement of electrons and lithium ions within a battery cell can generate gases and heat faster than the battery housing can dissipate the generated gases and heat. The excess gases and heat can lead to pressure buildup within the battery housing. In some cases, a dangerous condition in an individual battery cell, such as an uncontrolled temperature rise, can adversely affect adjacent battery cells within the battery housing. Eventually, the battery cells and / or battery packs can burn or explode, creating a highly hazardous condition. The battery packs can rapidly progress through stages of degradation, providing little time to detect and mitigate the hazardous condition before a chain reaction becomes irreversible.

[0028] In some cases, swelling or deformation of the battery housing may result from stress and abuse of the battery cells. Sometimes such abuse may be immediate and obvious, for example, a battery cell on an electric vehicle may be punctured or burst by flying debris. In other cases, abuse may occur over an extended period of time. For example, overcharging, over-discharging, exposure to high and low temperatures, and / or physical damage to the battery cells over an extended period of time may affect the internal operation of the battery cells, resulting in a swollen or deformed battery housing. Due to the hidden nature of many of these factors and the sudden onset of an unsafe battery condition, it may be difficult to predict and / or detect an unsafe battery condition before it is too late.

[0029] The onset of a dangerous battery condition may be preceded by various stages of battery degradation resulting in physical changes to the battery housing. For example, the battery cells may experience electrolysis, electrolyte evaporation, venting, and other events that lead to increased pressure and heat within the battery housing. Detecting deformations in the battery housing can provide an early indication of a dangerous battery condition and enable the use of mitigating measures in response to the condition.

[0030] Some current battery monitoring systems may utilize various sensors in proximity to the battery cells to determine the state of the battery cells based on physical characteristics of the environment in and around the battery housing. For example, a temperature sensor may be located on or near the surface of the battery cells. If the temperature measurement exceeds a predetermined maximum operating temperature, the battery monitoring system may issue a warning or alarm. Similarly, a pressure sensor may be located on or near the surface of the battery cells and may be configured to send an alarm if the pressure within the battery pack exceeds a predetermined maximum operating pressure. Detection systems utilizing temperature and pressure sensors are often expensive and may be difficult to configure within the confines of a battery pack. Additionally, temperature and pressure sensors may not provide an indication of a dangerous battery condition until the onset of the dangerous battery condition is irreversible.

[0031] Various exemplary embodiments described herein utilize various techniques to detect changes in a surface (e.g., a battery housing surface) using an optical fiber. For example, in some embodiments, an illumination source may emit a light output at a first end of an optical fiber. The optical fiber may be positioned on the surface and patterned to substantially cover the surface. A portion of the light output may be reflected back to the first end of the optical fiber (e.g., reflected light) due to irregularities in the optical fiber, stretching / compression of the optical fiber, bends / bends in the optical fiber, and other physical conditions of the optical fiber. A receiver may be positioned at the first end of the optical fiber to receive the reflected light and record the backscatter pattern (e.g., the pattern of light received at a photodiode).

[0032] Similarly, a portion of the optical power may be transmitted through the optical fiber (e.g., transmitted light) and received at a receiver positioned at a second end of the optical fiber, which may record the forward scattering pattern.

[0033] If the physical structure of the optical fiber changes due to deformation of the surface to which it is bonded, the backscattering pattern and / or the forward scattering pattern may change, and the change in the scattering pattern may be used to determine the location and magnitude of the deformation.

[0034] For example, in some embodiments, the backscattering pattern and the forward scattering pattern may be monitored by the controller. When deformation occurs on the surface, the optical fiber is strained. The strain in the optical fiber may cause a change in both the forward scattering pattern and the backscattering pattern. By continuously monitoring both the forward scattering pattern and the backscattering pattern, the controller can determine the time at which the forward scattering pattern and the backscattering pattern change due to deformation. The controller can then compare the time at which the forward scattering pattern changes relative to the backscattering pattern. The difference in time can be used to pinpoint the location of the strain in the optical fiber and therefore the deformation on the attached surface. By utilizing the change in time relative to each other, unmodified, off-the-shelf optical fibers can be used to provide a precise location. Utilizing unmodified, off-the-shelf optical fibers allows for larger surface coverage at a lower cost.

[0035] As a result of the exemplary embodiments described herein, in some instances, the effectiveness of deformation detection using optical fibers can be significantly improved. In addition, the use of unmodified optical fibers for accurate in-fiber strain detection can reduce manufacturing complexity and the overall cost of deformation detection on surfaces.

[0036] Referring now to FIG. 1, an exemplary fiber optic profiler 100 is provided. As shown in FIG. 1, the exemplary fiber optic profiler 100 includes a fiber optic pattern 102 (e.g., a light sensing fiber) optically coupled to an illumination source 104 and a first optical receiver 106 at a source end 102a and optically coupled to a second optical receiver 108 at a terminal end 102b. The illumination source 104 is configured to emit an optical output 112 into the fiber optic pattern 102 such that a transmitted light 116 is received at the second optical receiver 108 and a reflected light 114 is received at the first optical receiver 106. A reference signal 118 is further transmitted from the illumination source 104 to the first optical receiver 106. As further shown in FIG. 1, a controller 110 is electrically connected to the first optical receiver 106 and configured to receive a reflected light electrical signal 120 associated with the reflected light 114 received at the first optical receiver 106. The controller 110 is further electrically connected to the second optical receiver 108 and configured to receive a transmitted optical electrical signal 122 associated with the transmitted light 116 received at the second optical receiver 108 .

[0037] As shown in FIG. 1, an exemplary fiber optic profiler 100 includes a fiber optic pattern 102. The fiber optic pattern 102 is an optical fiber of any length configured to receive optical power 112 at a light source end 102a and transmit the optical power 112 through an optical transmission medium to a terminal end 102b. The fiber optic pattern 102 is attached to a surface (as shown in FIG. 2) such that surface variations compress and / or stretch the fiber optic pattern 102. The optical fibers that comprise the fiber optic pattern 102 may include optically coupled splices, occlusions, and / or other irregularities that cause a portion of the optical power 112 traveling through the fiber optic pattern 102 to be reflected toward the light source end 102a of the fiber optic pattern 102.

[0038] The reflected light 114 generates a backscattering pattern. The scattering pattern (e.g., speckle pattern) is a pattern of light output formed by constructive and destructive interference of light waves as the light travels through the optical fiber pattern 102. The scattering pattern is determined by various structures within the optical fiber. The scattering pattern can be used to determine changes in the optical fiber structure of the optical fiber pattern 102, for example, changes due to compression and / or stretching of the optical fiber.

[0039] Additionally, a portion of the optical output 112 is transmitted through the optical transmission medium that makes up the optical fiber pattern 102 and is received at termination 102b. The transmitted light 116, when received by the second optical receiver 108, produces a forward scattering pattern.

[0040] In some embodiments, the optical fiber pattern 102 may include an unmodified, prefabricated optical fiber. An unmodified optical fiber does not include any intentional structures, such as fiber Bragg gratings or other optical structures. However, an unmodified optical fiber includes certain anomalies inherent to the optical fiber manufacturing process.

[0041] As further shown in FIG. 1, the exemplary fiber optic profiler 100 includes an illumination source 104. The illumination source 104 is any single light source or an array of light sources configured to generate a light output 112 configured to transmit at least partially through an optical fiber (e.g., the optical fiber pattern 102). The illumination source 104 may be any semiconductor, diode, or other photon emitting structure configured to generate a laser light output 112. The illumination source 104 may be configured to generate a light output 112 at a particular wavelength or spectrum of wavelengths. For example, the illumination source 104 may be configured to generate a light output 112 having a wavelength between 780 nanometers and 2200 nanometers. In some embodiments, the illumination source 104 may be a laser diode.

[0042] 1, the illumination source 104 is further configured to transmit a reference signal 118 to the first optical receiver 106. The reference signal 118 is a portion of the optical output 112. The reference signal 118 may be created by transmitting the optical output 112 through an optical beam splitter. The reference signal 118 may be utilized to compare the optical output 112 to the reflected light 114.

[0043] As further shown in FIG. 1, the exemplary optical fiber profiler 100 includes a first optical receiver 106 and a second optical receiver 108. The optical receivers 106, 108 are any devices, sensors, photodiodes, or other structures that generate an electrical current (e.g., reflected photoelectric signal 120, transmitted photoelectric signal 122) corresponding to light received at the optical receiver 106 (e.g., reflected light 114, transmitted light 116). The optical receivers 106, 108 may comprise an array of pixels, each configured to convert photons into an electrical current. The optical receivers 106, 108 may be configured to capture a scattering or speckle pattern by converting the intensity of light received at each pixel of the optical receiver 106, 108 into an electrical current. In some embodiments, the exemplary optical receivers 106, 108 may be configured to generate an electrical current (e.g., reflected photoelectric signal 120, transmitted photoelectric signal 122) that includes a set or array of intensities that form the scattering pattern of the corresponding optical receiver 106, 108.

[0044] As further shown in FIG. 1, the exemplary optical fiber profiler 100 includes a controller 110. The controller 110 is any computing device electrically connected to the first optical receiver 106 and the second optical receiver 108 and configured to receive the reflected optical electrical signal 120 and the transmitted optical electrical signal 122 and detect the corresponding surface change based on the received electrical signal. The controller 110 can utilize the intensity of the light received at the first optical receiver 106 and the second optical receiver 108 to determine the magnitude or height of the deformation. For example, a deformation having a large magnitude or height can significantly change the optical fiber pattern 102 on the attached surface. Thus, a dramatic change in the scattering pattern can indicate a significant expansion of the attached surface. Similarly, significant loss and / or reflection in the optical fiber can be an indication of the magnitude of the change and / or deformation. The exemplary controller 110 architecture is further described in connection with FIG. 8.

[0045] In addition to determining the magnitude (e.g., height) of the deformations, the controller 110 can utilize the reflected photoelectric signal 120 and the transmitted photoelectric signal 122 to determine the location of the one or more deformations on the attached surface. In some embodiments, the controller 110 can determine the location of the one or more deformations based on the time difference between a change in the forward scattering pattern and a change in the back scattering pattern. Determining the exact location of the one or more deformations on the attached surface is further described in connection with FIG.

[0046]

[0023] Referring now to Figure 2, an exemplary fiber optic profiler 200 is provided. As shown in Figure 2, the exemplary fiber optic profiler 200 includes a fiber optic pattern 202 attached to a surface 224. The fiber optic pattern 202 is configured to receive a light output 212 from an illumination source 204 optically coupled via a fiber optic coupler 228 at a light source end 202a of the fiber optic pattern 202. A portion of the light output 212 is transmitted through the fiber optic pattern 202 and received at a terminal end 202b of the fiber optic pattern 202 as transmitted light 216 by an optically coupled second receiver 208. As further shown in Figure 2, a portion of the light output 212 is reflected back to the light source end 202a of the fiber optic pattern 202 and received as reflected light 214 by an optically coupled first receiver 206. As shown in Figure 2, both the first receiver 206 and the illumination source 204 are optically coupled to the fiber optic pattern 202 by a fiber optic coupler 228. FIG. 2 further illustrates the deformation 226 of the surface 224 to which the optical fiber pattern 202 is attached.

[0047] As shown in FIG. 2, the exemplary fiber optic profiler 200 is attached to a surface 224. The surface 224 may comprise any area, shape, material, or structure to which the fiber optic pattern 202 may be attached such that the optical power 212 may be transmitted through the fiber optic pattern 202. Although shown in FIG. 2 as a flat surface, the surface 224 may include any shape or structure. In some embodiments, the surface 224 may be a surface of a battery case, package, pack, or housing. In such a case, a deformation on the surface 224 (e.g., deformation 226) may be an indication of a potentially dangerous battery condition, such as pressure buildup inside the battery compartment, excessive heat on or around the battery, and / or the onset of a thermal runaway event.

[0048] 2, the attached surface 224 includes a deformation 226. The deformation 226 is any anomaly, protrusion, dent, distortion, warp, bend, or other change in the physical structure of the surface 224. The fiber optic profiler 200 is configured to detect the changes in the surface 224, such that any change to the surface 224 can be detected as a deformation 226.

[0049] As described in connection with FIG. 1, the fiber optic profiler 200 is configured to determine the location of any deformations 226 on the attached surface 224. In operation, the fiber optic profiler 100 can transmit an optical output 212 through the fiber optic pattern 202, either in pulses or continuously as a continuous light source. A controller (e.g., controller 110 as shown in FIG. 1) continuously receives the scattering pattern through each of the electrical signals (e.g., reflected photoelectric signal 120 and transmitted photoelectric signal 122). A change in the scattering pattern due to the deformations 226 of the attached surface 224 can cause a change in the scattering pattern. Depending on when the change in the scattering pattern is detected at the first optical receiver 206 and the second optical receiver 208, a location within the fiber optic pattern 202 can be determined.

[0050] For example, generally, if a change in the scattering pattern is first detected in the backscattered pattern received at the first receiver 206, the deformation is in the first half of the optical fiber pattern 202. Similarly, if a change in the scattering pattern is first detected in the forward scattered pattern received at the second receiver 208, the deformation is in the second half of the optical fiber pattern 202. Furthermore, if a change in the scattering pattern is detected at exactly the same time at the first receiver 206 and the second receiver 208, the deformation is in the exact center of the optical fiber pattern 202.

[0051] These overarching principles allow for the determination of precise locations within optical fiber pattern 202. For example, the precise locations of deformations along the length (L) of the optical fibers that make up optical fiber pattern 202 can be determined using equations similar to the following:

[0052]

number

[0053] As a specific example, the total time (t total ) is 25 nanoseconds (note that in a typical fiber with an index of refraction of 1.5, light travels 1.5 times slower), and if a change in the scattering pattern is detected at the first receiver 206 5 nanoseconds before the change in the scattering pattern is detected at the second receiver 208, the controller can determine that the location of the deformation 226 is:

[0054]

number

[0055] By determining the exact location of the deformation 226 on the attached surface based on the relative arrival times of the change in the forward scattering pattern versus the change in the back scattering pattern, simple, low-cost components may be used. By using two data points to precisely determine the location of the deformation 226, both of which are determined using low-cost components, negating the larger standard error of each of the components in the overall result. Thus, ultra-precise and expensive receivers and illumination sources are not required.

[0056] In some embodiments, the location may be determined using a single optical receiver positioned at the source end 202a or the terminal end 202b of the optical fiber pattern 102. In such cases, the exact location of the deformation 226 may be determined based on the change in the scattering pattern detected at one end of the optical fiber pattern. An exemplary optical fiber profiler 100 utilizing a single optical receiver is further described in connection with FIG.

[0057] 3A-3B, an exemplary battery housing tray 330 is provided that includes a fiber optic pattern 302. As shown in Figures 3A and 3B, the fiber optic pattern 302 of the exemplary fiber optic profiler is attached to a surface 324 of a battery housing 332. As further shown in Figures 3A and 3B, the fiber optic pattern 302 is attached to the surface 324 using a bonding layer 334.

[0058] As shown in FIGS. 3A and 3B, the optical fiber pattern 302 is attached to a surface 324 of a battery housing 332. The battery housing 332 may be any structure, packaging, enclosure, and / or compartment for enclosing and / or protecting the internal components of the battery. The battery housing 332 may further define a space or compartment within which the internal battery components and battery cells may be disposed. In some embodiments, the battery housing 332 may include aluminum, steel, or other metals, plastic and / or reinforced plastic, or any other material capable of protecting the internal components of the battery pack. In some embodiments, the battery housing 332 may provide a structure for supporting, mounting, and / or isolating the battery cells, as well as wiring, and / or other internal components of the battery pack. Today, many electric vehicles are beginning to place multiple battery cells within a battery housing 332 that is integrated as part of the body of the electric vehicle. This technology has become popularly known as cell-to-chassis technology. Such battery arrangements may be particularly susceptible to unsafe battery conditions, such as thermal runaway and / or eventual combustion as a result of mechanical, electrical and / or thermal stress and abuse. By attaching the fiber optic pattern 302 to one or more surfaces 324 of the battery housing 332, deformations of the battery housing 332 may be detected, indicating the onset of an unsafe battery condition.

[0059] 3A and 3B, the fiber optic pattern 302 is attached to a surface 324 of the battery housing 332 using a bonding layer 334. The bonding layer 334 is any material, structure, or device used to attach the fiber optic pattern 302 to the surface 324 of the battery housing 332. The fiber optic pattern 302 is attached to the surface 324 such that when the surface 324 changes and / or deforms, the fiber optic pattern also deforms. The stretching and / or compression of the fiber optic pattern 302 due to the deformation on the surface 324 causes a change in the forward and backscattering patterns of the light outputs (e.g., light outputs 112, 212) traveling through the optical fibers of the fiber optic pattern 302.

[0060] 4A-4B, an exemplary battery pack 440 is provided. As shown in FIG 4A, the exemplary battery pack 440 includes a battery housing 432 and a battery cover 442 that completely enclose the internal components of the battery pack 440.

[0061] As further shown in FIG. 4B, the exemplary battery pack 440 includes a number of battery cells 444 positioned within the battery housing 432. The battery cells 444 may be any electrochemical device that utilizes a chemical reaction to generate electrical energy. The chemical reaction within the battery cells 444 may involve the transfer of ions between a positively charged electrode (cathode) and a negatively charged electrode (anode). When the battery cells 444 provide power to a load, the flow of electrons from the anode to the cathode generates an electrical current that flows from the cathode to the anode. The battery cells may contain any of a wide variety of chemical compositions (e.g., lithium-nickel-manganese-cobalt oxide, lithium iron phosphate, etc.). Battery cells 444 that facilitate such chemical reactions may be susceptible to a number of dangerous battery conditions that result in deformation of the battery housing 432 and / or the battery cover 442. For example, the battery cells 444 may generate excessive heat and / or gases, causing pressure to spike within the battery pack 440.

[0062] 4B, the fiber optic pattern 402 may be attached to a bottom surface 424 of a battery housing 432 in a battery housing tray 430 using a bonding layer 434. Thus, any deformation caused by the battery cells 444 or otherwise may cause stress and / or compression in the fiber optic pattern 402. Detecting the deformation may allow for detection of an unsafe battery condition.

[0063] 5A-5B, an exemplary battery pack 540 is provided, along with a cross-sectional view of the battery pack 540. As shown in FIG 5A, the exemplary battery pack 540 includes a battery housing 532 and a battery cover 542, which completely enclose the internal components of the battery pack 540.

[0064] 5B, the fiber optic pattern 502 is attached to a surface 524 of a battery cover 542 by an adhesive layer 534. A plurality of battery cells 544 are further shown proximate to the fiber optic pattern 502 within a common interior compartment created by the battery housing 532 and the battery cover 542.

[0065] 6, an expanded view of a cross section of an exemplary battery pack 640 is provided. As shown in FIG. 6, a battery housing 632 and a battery cover 642 form an enclosure around a plurality of battery cells 644. As further shown in FIG. 6, a fiber optic pattern 602 is attached to a surface 624 of the battery housing 632 proximate to the plurality of battery cells 644 with a bonding layer 634. Any deformation of the surface 624 due to degradation of the battery cells 644, or any other change in the surface 624, may be detected by a strain applied to the attached fiber optic pattern 602.

[0066] 7, an alternative fiber optic pattern 702 is provided. As shown in FIG. 7, a single end of the optical fiber that comprises the fiber optic pattern 702 is accessible. In such an embodiment, the optical power 712 may be transmitted into the exposed end. In such an embodiment, the location of any deformation may be determined based on the time at which a change in the backscattering pattern, as evidenced by reflected light 714, is detected.

[0067] 7, in some embodiments, the fiber optic profiler may include a single optical receiver (e.g., optical receiver 108, 208) optically coupled to the exposed terminal end of the optical fiber profile. In such embodiments, the location of any deformation may be determined based on the time at which a change in the forward scattering pattern, as evidenced by the transmitted light, is detected.

[0068] Referring now to FIG. 8, a detailed example of a sensing interferometer 880 is provided. In some embodiments, the sensing interferometer 880 may be utilized at the light source end 802a of the optical fiber pattern 802. As shown in FIG. 8, the sensing interferometer 880 receives an optical output 812 at one or more frequencies, for example, from a tunable laser source (e.g., the illumination source 804). The sensing interferometer 880 includes a first coupler 884 configured to transmit a portion of the optical output 812 as a measurement signal 886 and transmit a portion of the optical output 812 as a reference signal 888. The measurement signal 886 is transmitted to a circulator 890. As shown in FIG. 8, the circulator 890 includes three ports 890a-890c. Circulator 890 is configured to receive measurement signal 886 at a first port 890a and output measurement signal 886 as optical output 812 at a second port 890b that is optically coupled to light source end 802a of optical fiber pattern 802. As further shown in FIG. 8, circulator 890 is configured to receive reflected light at second port 890b and output reflected light 814 at a third port 890c.

[0069] 8, the sensing interferometer 880 includes a second coupler 892 configured to receive the reference signal 888 and the reflected light 814. By comparing the reflected light 814 to the reference signal 888, the coupler 892 can, in combination with an analog-to-digital converter (ADC), generate a scattering pattern and / or determine changes in the scattering pattern. In some embodiments, the scattering pattern can be detected using the array sensor without the need for a reference signal 888.

[0070] 9 illustrates an example controller 110 according to at least some example embodiments of the present disclosure. The controller 110 includes a processor 902, input / output circuitry 904, a data storage medium 906, a communication circuitry 908, a source end receiver circuitry 910, and a terminal end receiver circuitry 912. In some embodiments, the controller 110 is configured to use one or more of the sets of circuits 902, 904, 906, 908, 910, and / or 912 to perform and implement the operations described herein.

[0071] Although the components are described in terms of functional limitations, it should be understood that a particular implementation necessarily involves the use of specific computing hardware. It should also be understood that in some embodiments, some of the components described herein include similar or common hardware. For example, two sets of circuits both leverage the use of the same processor(s), network interface(s), storage medium(s), etc. to perform their associated functions, so that duplicate hardware is not required for each set of circuits. Thus, users of the term "circuitry" as used herein with respect to components of the apparatus described herein should be understood to include specific hardware configured to perform the functions associated with the specific circuitry described herein.

[0072] In particular, the term "circuitry" should be broadly understood to include hardware and, in some embodiments, software for configuring hardware. For example, in some embodiments, "circuitry" includes processing circuitry, storage media, network interfaces, input / output devices, etc. Alternatively or additionally, in some embodiments, other elements of controller 110 provide or complement the functionality of other particular sets of circuits. For example, in some embodiments, processor 902 provides processing functionality for any of the sets of circuits, data storage media 906 provides storage functionality for any of the sets of circuits, communication circuitry 908 provides network interface functionality for any of the sets of circuits, etc.

[0073] In some embodiments, the processor 902 (and / or a co-processor, or any other processing circuitry that assists or is otherwise associated with the processor) communicates with the data storage medium 906 via a bus for passing information between components of the controller 110. In some embodiments, for example, the data storage medium 906 is non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In other words, for example, in some embodiments, the data storage medium 906 includes or embodies an electronic storage device (e.g., a computer-readable storage medium). In some embodiments, the data storage medium 906 is configured to store information, data, content, applications, instructions, etc. to enable the controller 110 to perform various functions according to exemplary embodiments of the present disclosure.

[0074] The processor 902 may be embodied in a number of different ways. For example, in some exemplary embodiments, the processor 902 includes one or more processing devices configured to function independently. Additionally or alternatively, in some embodiments, the processor 902 includes one or more processor(s) configured in tandem via a bus to enable independent instruction execution, pipelining, and / or multithreading. Use of the terms "processor" and "processing circuitry" should be understood to include a single-core processor, a multi-core processor, multiple processors internal to the controller 110, and / or one or more remote or "cloud" processor(s) external to the controller 110.

[0075] In an exemplary embodiment, the processor 902 is configured to execute instructions stored in the data storage medium 906 or otherwise accessible to the processor. Alternatively or additionally, in some embodiments, the processor 902 is configured to execute hard-coded functions. Thus, whether configured by a hardware method or a software method, or a combination thereof, the processor 902 represents an entity (e.g., physically embodied in a circuit) capable of performing operations according to embodiments of the present disclosure while configured accordingly. Alternatively or additionally, as another example in some exemplary embodiments, when the processor 902 is embodied as an execution body of software instructions, the instructions specifically configure the processor 902 to perform algorithms embodied in specific operations described herein when such instructions are executed.

[0076] As one particular exemplary embodiment, the processor 902 is configured to perform various operations associated with detecting changes (e.g., deformations) on a surface. In some embodiments, the processor 902 includes hardware, software, firmware, and / or combinations thereof to receive a reflected optical electrical signal (e.g., reflected optical electrical signal 120) corresponding to reflected light (e.g., reflected light 114, 214) received at a first optical receiver (e.g., optical receiver 106, 206) positioned at the light source end of an optical fiber (e.g., optical fiber pattern 102, 202, 302, 402, 502, 602, 702, 802). Additionally or alternatively, in some embodiments, the processor 902 includes hardware, software, firmware, and / or a combination thereof to receive a transmitted optical electrical signal (e.g., transmitted optical electrical signal 122) corresponding to the transmitted light (e.g., transmitted light 116, 216) received at a second optical receiver (e.g., optical receiver 108, 208) positioned at a terminal end of the optical fiber (e.g., optical fiber pattern 102, 202, 302, 402, 502, 602, 702, 802). Additionally or alternatively, in some embodiments, the processor 902 includes hardware, software, firmware, and / or a combination thereof to detect changes in the surface based at least in part on the reflected light and the transmitted light.

[0077] In some embodiments, the controller 110 includes input / output circuitry 904 that provides output to a user and, in some embodiments, receives indications of user input. In some embodiments, the input / output circuitry 904 communicates with the processor 902 to provide such functionality. The input / output circuitry 904 may comprise one or more user interface(s) (e.g., user interfaces), and in some embodiments includes a display with interface(s) rendered as a web user interface, an application user interface, a user device, a back-end system, etc. The processor 902 and / or the input / output circuitry 904 including the processor may be configured to control one or more functions of one or more user interface elements via computer program instructions (e.g., software and / or firmware) stored on memory accessible to the processor (e.g., data storage medium 906, etc.). In some embodiments, the input / output circuitry 904 includes or utilizes user-facing applications to provide input / output functionality to client devices and / or other displays associated with the user.

[0078] In some embodiments, the controller 110 includes a communications circuit 908. The communications circuit 908 includes any means, such as a device or circuit embodied in either hardware or a combination of hardware and software, configured to transmit and receive data to and from a network and / or any other device, circuit, or module in communication with the controller 110. In this regard, the communications circuit 908 includes, for example, in some embodiments, a network interface for enabling communication with a wired or wireless communication network. Additionally or alternatively, in some embodiments, the communications circuit 908 includes one or more network interface card(s), antenna(s), bus(es), switch(es), router(s), modem(s), and supporting hardware, firmware, and / or software, or any other device suitable for enabling communication over one or more communications network(s). Additionally or alternatively, the communications circuit 908 includes circuitry for interacting with the antenna(s) and / or other hardware or software to cause transmission of signals via the antenna(s) or control reception of signals received via the antenna(s). In some embodiments, the communications circuitry 908 enables data to be transmitted to and received from client devices in communication with the controller 110 .

[0079] The source end receiver circuit 910 includes hardware, software, firmware, and / or combinations thereof that support various functionality associated with configuring and / or communicating with source end circuits, such as illumination sources, source end receivers, and / or source end sensing interferometers. In some embodiments, the source end receiver circuit 910 includes hardware, software, firmware, and / or combinations thereof to communicate with the source end circuits according to established protocols to provide appropriate configuration and / or calibration parameters and / or receive data provided by each component of the source end circuits. In some embodiments, the source end receiver circuit 910 includes a separate processor, a specially configured field programmable gate array (FPGA), or a specially programmed application specific integrated circuit (ASIC).

[0080] The termination receiver circuit 912 includes hardware, software, firmware, and / or combinations thereof that support various functionality related to configuring and / or communicating with a termination circuit, such as a termination receiver. In some embodiments, the source end receiver circuit 910 includes hardware, software, firmware, and / or combinations thereof to communicate with the source end circuit according to an established protocol to provide appropriate configuration and / or calibration parameters and / or receive data provided by the source end circuit. In some embodiments, the source end receiver circuit 910 includes a separate processor, a specially configured field programmable gate array (FPGA), or a specially programmed application specific integrated circuit (ASIC).

[0081] Additionally or alternatively, in some embodiments, one or more of the sets of circuits 902-912 are combinable. Additionally or alternatively, in some embodiments, one or more of the sets of circuits perform some or all of the functions described in relation to another component. For example, in some embodiments, one or more of the sets of circuits 902-912 are combined into a single module embodied in hardware, software, firmware, and / or combinations thereof. Similarly, in some embodiments, one or more of the sets of circuits, e.g., source end receiver circuit 910 and / or termination end receiver circuit 912, are combined such that processor 902 performs one or more of the operations described above with respect to each of these circuits individually.

[0082] 10, an exemplary three-dimensional model 1000 is provided that illustrates a number of deformations 1026 on a surface. As shown in FIG. 10, the three-dimensional model 1000 of the surface can be generated based on the transmitted light (e.g., transmitted light 116, 216) and reflected light (e.g., reflected light 114, 214, 814) received from the optical fiber pattern (e.g., 102, 202, 302, 402, 502, 602, 702, 802). As described herein, the exact location of the deformation or other change to the surface can be determined based on the time difference between the change in the scattering pattern detected at the light source end compared to the change in the scattering pattern detected at the termination end of the optical fiber pattern. In addition, the magnitude (e.g., height) of the deformation can be determined based on the forward and / or backward scattering patterns. The location of the deformation and the magnitude of the deformation can be used to generate a three-dimensional model, such as the three-dimensional model 1000 illustrated in FIG. 10. In some embodiments, the contour of the three-dimensional model 1000 can be modeled based on known characteristics of the modeled surface in conjunction with the detected deformations.

[0083] 11, an exemplary process 1100 is provided for detecting changes in a surface (e.g., surface 224, 324, 424, 524, 624) using an optical fiber (e.g., optical fiber pattern 102, 202, 302, 402, 502, 602, 702, 802). In block 1102, the optical fiber profiler (e.g., optical fiber profiler 100, 200) transmits optical power by an illumination source (e.g., illumination source 104, 204, 804) into a first end (e.g., light source end 102a, 202a, 802a) of the optical fiber, the optical fiber being positioned above the surface. As described herein, the illumination source may be a laser diode or similar light source configured to transmit an optical output, such as an optical pulse or a continuous light wave (e.g., optical output 112, 212, 812). The illumination source is coupled to the first end of the optical fiber such that the optical output is transmitted through the optical fiber. A portion of the optical power may be reflected back to the light source end of the optical fiber (e.g., reflected light 114, 214, 814) due to structures, aberrations, occlusions, stretches, compressions, and other anomalies in the optical fiber. A portion of the optical power may reach the terminal end of the optical fiber (e.g., terminal end 102b, 202b, 802b) as transmitted light (e.g., transmitted light 116, 216, 816).

[0084] At block 1104, the optical fiber profiler receives the reflected light at a first optical receiver (e.g., optical receiver 106, 206, sensing interferometer 880) positioned at a first end of the optical fiber. As described herein, the reflected light may be captured by the first optical receiver positioned at the source end of the optical fiber and configured to generate a backscattering pattern representative of the physical configuration of the optical fiber. In some embodiments, the backscattering pattern may be transmitted to a controller (e.g., controller 110, device 900) as a reflected optical electrical signal (e.g., reflected optical electrical signal 120).

[0085] At block 1106, the optical fiber profiler receives the transmitted light at a second optical receiver (e.g., optical receiver 108, 208) positioned at a second end of the optical fiber. As described herein, the transmitted light may be captured by the second optical receiver positioned at a terminal end of the optical fiber and configured to generate a forward scattering pattern representative of the physical configuration of the optical fiber. In some embodiments, the forward scattering pattern may be transmitted to the controller as a transmitted optical-electrical signal (e.g., transmitted optical-electrical signal 122).

[0086] At block 1108, the fiber optic profiler detects changes in the surface based at least in part on the reflected and transmitted light. As described herein, the controller can detect changes, such as deformations, in the attached surface and further determine a location and magnitude of the deformations. In one embodiment, the controller can detect the changes in the surface based on changes to the forward scattering pattern received at the second receiver and / or the back scattering pattern received at the first receiver. In at least one embodiment, the controller can further detect a location of the deformation on the surface based on a time difference between the change in the forward scattering pattern received at the second receiver and the change in the back scattering pattern received at the first receiver. In some embodiments, a three-dimensional model, such as the three-dimensional model 1000 shown in FIG. 10, can be generated based on the location and magnitude of the deformation on the surface.

[0087] As described herein, in at least one embodiment, a fiber optic profiler may be utilized to detect changes and / or deformations in the surface of a battery housing (e.g., battery housing 332, 432, 532, 632). Such determination may be indicative of a dangerous battery condition, such as pressure, gas, and / or heat buildup and / or the onset of thermal runaway. Utilizing both forward and backscatter patterns to determine the location of deformations may allow for the use of readily available and inexpensive electrical components.

[0088] Many modifications and other embodiments of the inventions described herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. The drawings show only certain components of the apparatus described herein, it being understood that various other components may be used in conjunction with the system. It is therefore to be understood that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, the steps in the methods described above need not necessarily be performed in the order depicted in the accompanying drawings, and in some cases one or more of the depicted steps may be performed substantially simultaneously or additional steps may be included. Although specific terms have been employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0089] Although various embodiments according to the principles disclosed herein have been shown and described above, modifications thereof may be made by those skilled in the art without departing from the spirit and teachings of the present disclosure. The embodiments described herein are merely representative and are not intended to be limiting. Many variations, combinations and modifications are possible and are within the scope of the present disclosure. Although the disclosed embodiments relate primarily to battery housings in electric vehicles, those skilled in the art may recognize that such principles may be applied to any surface where it may be beneficial to detect changes to the surface using optical fibers. Alternative embodiments resulting from combining, integrating and / or omitting features of the embodiment(s) are also within the scope of the present disclosure. Thus, the scope of protection is not limited by the description set forth above.

[0090] In addition, the section headings used herein are provided to conform to the suggestions of 37 C.FR 1.77 or to otherwise provide organizational guidance, and are not intended to limit or characterize the invention(s) recited in any claim that may be issued from this disclosure.

[0091] Use of broader terms such as "comprises," "includes," and "having" should be understood to provide support for narrower terms such as "consisting of," "consisting essentially of," and "comprised substantially of." Use of terms such as "optionally," "may," "might," and "possibly" with respect to any element of an embodiment means that the element is not required, or that the element is alternatively required, with both options being within the scope of the embodiment. Also, references to examples are provided merely for illustrative purposes and are not intended to be exclusive.

Claims

1. An apparatus comprising:

1. An optical fiber having a first end and a second end, an optical fiber, the optical fiber being positioned on a surface; an illumination source configured to emit a light output into the first end of the optical fiber; a first optical receiver configured to receive reflected light at the first end of the optical fiber; a second optical receiver configured to receive transmitted light at the second end of the optical fiber; An apparatus, wherein a change in the surface is detected based at least in part on the reflected light and the transmitted light.

2. 2. The apparatus of claim 1, wherein the two-dimensional location of the change in the surface is determined based on a time difference between a backscattering pattern change detected at the first receiver and a forward scattering pattern change detected at the second receiver.

3. 2. The apparatus of claim 1, wherein a three-dimensional model of the surface is generated based at least in part on the transmitted light and the reflected light, the three-dimensional model including two-dimensional positions of the changes in the surface and magnitudes of the changes in the surface.

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