Flexible distributed strain sensor

Abstract

The present invention provides a flexible distributed strain sensor, which relates to the field of sensing and measurement and control technology. The flexible distributed strain sensor comprises: a flexible wire, a signal transceiver connected to the flexible wire and a controller. The flexible wire comprises a first liquid metal wire with a uniform conductive layer size wrapped in a flexible sleeve and a second liquid metal wire with a variable conductive layer size, the second liquid metal wire comprises M+1 sections of flexible units, and a flexible insulator that can cause the conductive layer size to change is included between two adjacent sections of the flexible units. In an initial state, the signal transceiver transmits a test waveform to the first liquid metal wire and the second liquid metal wire, and the controller determines a baseline waveform according to the reflected waveform. The signal transceiver periodically transmits a test waveform to the flexible wire. The controller determines the deformation position and deformation type of the flexible wire according to the reflected waveform and the baseline waveform within a measurement period.

Description

Technical Field

[0001] The present disclosure relates to the field of sensing and measurement and control technology, and in particular to a flexible distributed strain sensor. Background Art

[0002] With the development of deformation measurement technology, the requirements for the accuracy of landslide monitoring are getting higher and higher.

[0003] Landslide deformation mainly includes surface deformation and deep deformation. Generally, landslide deformation has a large deformation range, a long deformation duration, complex deformation evolution behavior (for example, the deformation speed is very slow or has mutation), complex terrain, and the environment changes with time and space.

[0004] At present, TDR (Time Domain Reflectometry) technology is widely used in landslide monitoring. TDR technology is based on the mechanism that when electromagnetic waves are transmitted in cables, they will generate reflected waves when encountering different medium interfaces or faults to measure deformation. One method is to use TDR technology based on coaxial cables to install coaxial cables in the boreholes of landslides for deep deformation measurement. However, the elastic modulus of coaxial cables is usually greater than 10GPa, which leads to small deformation on the coaxial cables under small slip stress, and the change of reflected signals caused is not obvious. Only obvious large deformation can be detected, and large deformation usually easily causes the coaxial cable to break and cause measurement failure, and it cannot be reused. Another method is to use TDR technology based on flexible wires for measurement, but the current measurement method based on flexible wires can only determine that the overall tensile deformation has occurred, and cannot accurately locate the location of tensile deformation. In the case of tensile and compressive deformation at the same time, the specific location and type of tensile deformation and compressive deformation cannot be determined.

[0005] Therefore, the above two deformation measurement methods have low reliability and poor accuracy. Summary of the invention

[0006] In order to overcome the problems existing in the related art, the present disclosure provides a flexible distributed strain sensor.

[0007] According to a first aspect of an embodiment of the present disclosure, a flexible distributed strain sensor is provided, wherein the flexible conductor comprises a first liquid metal conductor with a uniform conductive layer size wrapped in a flexible sleeve and a second liquid metal conductor with a variable conductive layer size, wherein there is no electrical connection between the first liquid metal conductor and the second liquid metal conductor, and the second liquid metal conductor comprises M+1 segments of flexible units, wherein a flexible insulator that can cause the conductive layer size to change is included between two adjacent segments of the flexible units, and M is a positive integer; in an initial state, the signal transceiver transmits a test waveform to the first liquid metal conductor and the second liquid metal conductor, and receives a reflected waveform of the first liquid metal conductor and the second liquid metal conductor, and the controller determines a baseline waveform according to the reflected waveform; the signal transceiver periodically transmits the test waveform to the flexible conductor, and receives a reflected waveform of the first liquid metal conductor and the second liquid metal conductor; and the controller determines a deformation position and a deformation type of the flexible conductor according to the reflected waveform and the baseline waveform within a measurement period.

[0008] Optionally, the flexible insulator is a protrusion protruding toward the liquid metal, or a groove sunken toward the flexible insulating layer, and the flexible insulating layer is a flexible sleeve.

[0009] Optionally, in the initial state, there are peaks at both ends of the first baseline waveform of the first liquid metal wire, and there are peaks at both ends of the second baseline waveform of the second liquid metal wire and at the position where the flexible insulator is provided.

[0010] Optionally, if the first reflection waveform is the same as the first baseline waveform, and the second reflection waveform is the same as the second baseline waveform, the controller determines that the flexible wire has not been deformed; wherein the first reflection waveform is the reflection waveform of the first liquid metal wire, and the second reflection waveform is the reflection waveform of the second liquid metal wire.

[0011] Optionally, if the number of peaks of the first reflected waveform is the same as the number of peaks of the first baseline waveform, and the time length of the first reflected waveform is greater than the time length of the first baseline waveform, the controller determines that the flexible wire has not undergone compressive deformation but has undergone tensile deformation; if the number of peaks of the first reflected waveform is different from the number of peaks of the first baseline waveform, and the time length of the first reflected waveform is equal to the time length of the first baseline waveform, the controller determines that the flexible wire has undergone compressive deformation but not tensile deformation; if the number of peaks of the first reflected waveform is different from the number of peaks of the first baseline waveform, and the time length of the first reflected waveform is different from the time length of the first baseline waveform, the controller determines that the flexible wire has undergone compressive deformation and no tensile deformation.

[0012] Optionally, if the first reflected waveform and the first baseline waveform have the same time length, and the first reflected waveform has K new peaks compared to the first baseline waveform, the controller determines that the K new peaks all correspond to K compression deformations; the controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire based on the time difference between each peak of the K peaks and the peak of the first end of the first reflected waveform, and determines the K compression positions of the first liquid metal wire.

[0013] Optionally, the controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire according to the time difference between each of the K peaks and the peak at the first end of the first reflected waveform, and determines the K compression positions of the first liquid metal wire, including: the controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire based on the time difference between the i-th peak and the peak at the first end of the first reflected waveform and a first preset formula, so as to determine the various positions where the flexible wire undergoes compression deformation; wherein the first preset formula is: ; represents the length from the i-th wave peak among the K wave peaks from the corresponding position of the first liquid metal wire to the starting end of the first liquid metal wire, i is an integer greater than or equal to 1 and less than or equal to K, represents the time difference between the ith peak and the first peak of the first reflected waveform, Indicates the propagation speed of electromagnetic waves in the flexible wire.

[0014] Optionally, after determining the compression position based on the first liquid metal wire, the controller determines the peak generated by the flexible insulator in the second reflection waveform based on the second reflection waveform, and determines the characteristics of the tensile deformation according to the target time difference in the second reflection waveform and the time difference between two adjacent peaks in the second baseline waveform; wherein the target time difference includes, in sequence: the time difference between the starting end peak and the peak corresponding to the first flexible insulator, the time difference between the peaks corresponding to each two adjacent flexible insulators, and the time difference between the peak corresponding to the last flexible insulator and the end peak.

[0015] Optionally, if the first reflected waveform and the first baseline waveform have the same number of peaks and different total durations, and the second reflected waveform and the second baseline waveform have the same number of peaks and different total durations, the controller determines that no compression deformation occurs but tensile deformation occurs; the controller determines the characteristics of the tensile deformation based on the time difference between two adjacent peaks in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform.

[0016] Optionally, if , the controller determines that the j-th segment flexible unit undergoes stretching deformation, where represents the time difference between the jth peak and the j+1th peak in the second reflected waveform, represents the time difference between the j-th peak and the j+1-th peak in the second baseline waveform, where j is a positive integer less than or equal to M+1.

[0017] According to a second aspect of an embodiment of the present disclosure, a deformation measurement device is provided, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to: execute the steps executed by the controller in the flexible distributed strain sensor described in the first aspect above.

[0018] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0019] In the disclosed embodiment, the flexible distributed strain sensor includes two flexible wires of liquid metal transmission wires of different structures, uniform structure and non-uniform structure. Since the reflection wave characteristics of the liquid metal wire with uniform conductive layer structure and the liquid metal wire with variable conductive layer size are different, the signal transceiver can first measure the baseline waveform of the liquid metal wire with two structures based on the flexible wire, respectively obtain the baseline waveform of the uniform liquid metal wire and the baseline waveform of the non-uniform liquid metal wire, and then periodically send electromagnetic waves to the two structural wires in the flexible wire. The controller retrieves the waveform of the two reflected waves and the characteristic analysis of the two baseline waveforms through docking. Since the characteristics of the reflection waves generated by deformation of the two liquid metal wires are different, and the flexible wire includes distributed flexible units, it can be judged whether deformation occurs on each flexible unit of the flexible wire based on the change of the reflection waves and baseline waves of the two liquid metal wires, and the type and position of the deformation and other information are analyzed based on the waveform when deformation occurs. That is, the monitoring accuracy is high, the repeatability is high, and multiple deformation types can be monitored to provide comprehensive and accurate data, which is of great significance for improving the efficiency of landslide early warning in the monitored area, optimizing the structural maintenance plan of the monitored area, and enhancing the overall safety of the system. When a traditional flexible conductor is stretched and deformed at one position, the entire conductor will deform. Only the length after the overall stretching can be determined, but the specific position of the stretching deformation cannot be accurately located. That is, if tensile stress exists at multiple discontinuous positions, the traditional flexible conductor cannot accurately determine the position of each stretching segment and the length of each stretch, and the accuracy of deformation monitoring is poor. Traditional rigid conductors are easily broken when subjected to stress, and the accuracy and repeatability of deformation monitoring are poor.

[0020] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0022] Figure 1 A schematic diagram of the structure of a flexible distributed strain sensor provided in an embodiment of the present disclosure.

[0023] Figure 2 A schematic structural diagram of a first liquid metal wire provided in an embodiment of the present disclosure.

[0024] Figure 3 A schematic structural diagram of a second liquid metal wire provided in an embodiment of the present disclosure.

[0025] Figure 4 A schematic flow chart of a deformation measurement method provided in an embodiment of the present disclosure.

[0026] Figure 5 A schematic diagram of a baseline waveform of a flexible conductor provided in an embodiment of the present disclosure.

[0027] Figure 6 A waveform diagram of a monitored reflected wave provided in an embodiment of the present disclosure.

[0028] Figure 7 A waveform diagram of a monitored reflected wave provided in an embodiment of the present disclosure.

[0029] Figure 8 A hardware structure diagram of a computer device where the controller of an embodiment of the present disclosure is located. DETAILED DESCRIPTION

[0030] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0031] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0032] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0033] Next, the embodiments of the present disclosure are described in detail.

[0034] Figure 1 A schematic diagram of the structure of a flexible distributed strain sensor provided in an embodiment of the present disclosure is shown in FIG. Figure 1 As shown in the figure, the flexible distributed strain sensor 100 includes: a flexible wire 101, a signal transceiver 103 connected to the flexible wire 101 and a controller 102; the flexible wire 101 includes a first liquid metal wire 1011 with a uniform conductive layer size wrapped in a flexible sleeve and a second liquid metal wire 1012 with a variable conductive layer size, there is no electrical connection between the first liquid metal wire 1011 and the second liquid metal wire 1012, and the second liquid metal wire 1012 includes M+1 segments of flexible units ( Figure 1 The flexible unit is not shown in the figure), and a flexible insulator that can cause the size of the conductive layer to change is included between two adjacent flexible units, and M is a positive integer.

[0035] Specifically, a multiplexer can be connected between the flexible wire and the signal transceiver. Figure 1 The multiplexer is used to transmit two electromagnetic waves to the first liquid metal wire and the second liquid metal wire respectively through the multiplexer when the signal transceiver transmits electromagnetic waves to the flexible wire; when the electromagnetic wave reflected by the first liquid metal wire and the electromagnetic wave reflected by the second liquid metal are received, the two electromagnetic waves are sent together to the signal transceiver through the multiplexer.

[0036] It should be noted that after the flexible wire is deformed by a force, if the applied force is removed, the flexible wire can return to its original shape, so that deformation monitoring can be repeated based on the flexible wire.

[0037] It can be understood that the first liquid metal wire is a liquid metal wire without a flexible insulator disposed inside, and the second liquid metal wire is a liquid metal wire with a flexible insulator disposed inside.

[0038] It should be noted that, for the sake of convenience of explanation, in the example of the embodiment of the present disclosure, the starting end of the flexible wire, the starting end of the first liquid metal wire and the starting end of the second liquid metal wire are at the same position, and the end of the flexible wire, the end of the first liquid metal wire and the end of the second liquid metal wire are at the same position.

[0039] Specifically, the first liquid metal wire in the flexible wire is a wire with a uniform overall structure. In the embodiment disclosed herein, it is mainly used to determine the location where compression deformation occurs and to assist in determining tensile deformation. When the flexible wire is not deformed, the waveform reflected by the first liquid metal wire includes a peak reflected by the beginning of the first liquid metal wire and a peak reflected by the end of the first liquid metal. If the number of peaks in the waveform reflected by the first liquid metal wire does not change relative to the number of peaks in the first baseline waveform, no compression deformation occurs in the flexible wire. If the number of peaks in the waveform reflected by the first liquid metal wire increases relative to the number of peaks in the first baseline waveform, there must be a peak corresponding to the compression deformation of the flexible wire, and the newly added peak corresponds to the location where the compression deformation occurs. The location where the compression deformation of the flexible wire occurs can be accurately located based on the time difference between the peaks. If the length of the waveform reflected by the first liquid metal wire increases relative to the waveform length of the first baseline waveform, there must be tensile deformation, and the location and length of the tensile deformation are located in combination with the waveform reflected by the second liquid metal wire.

[0040] Figure 2 A schematic diagram of the structure of a first liquid metal wire provided in an embodiment of the present disclosure is shown in FIG. Figure 2 As shown in the figure, the material structure of the first liquid metal wire is uniform, and is composed of a liquid metal conductive core 201 and an outer insulating layer 202. The longitudinal section of the first liquid metal wire is shown as 203 in the figure. Among them, the size of the liquid metal conductive core 201 is uniform. If the flexible wire is not compressed or stretched, the diameter of the liquid metal conductive core 201 remains unchanged, and the peak position and the number of peaks of the reflected wave monitored by the signal transceiver do not change. If the flexible wire is compressed or stretched, the diameter of the liquid metal conductive core 201 will change, and at least one of the peak position and the number of peaks of the reflected wave monitored by the signal transceiver will change.

[0041] Optionally, in the embodiment of the present disclosure, the lengths of two adjacent flexible units may be the same or different, that is, the distribution of the flexible insulator may be uniform or non-uniform, and the embodiment of the present disclosure does not specifically limit this.

[0042] Optionally, the lateral distribution of the flexible insulators in the flexible wire may be uniform or uneven, and the sizes or cross-sections of the flexible insulators in the same wire may be the same or different, which is not specifically limited in the embodiments of the present disclosure.

[0043] Exemplarily, the flexible insulator between two adjacent flexible units may be a flexible groove, a flexible protrusion, or a flexible insulator of other shapes that can cause the size of the conductive layer to change, and the embodiments of the present disclosure do not specifically limit this.

[0044] Optionally, the flexible insulator is a protrusion protruding toward the liquid metal, or a groove sunken toward the flexible insulating layer, wherein the flexible insulating layer is a flexible sleeve of the flexible wire.

[0045] Specifically, an insulating block or a groove can be embedded in the adjacent flexible sleeve of the second liquid metal wire in the flexible wire, and the electromagnetic wave emitted by the signal transceiver to the second liquid metal wire will reflect a wave crest after encountering the insulating block or the groove, that is, the second liquid metal wire can be used to accurately determine whether the flexible wire is stretched and deformed. When the flexible wire is not deformed, the second liquid metal wire will reflect a wave crest at the beginning of the second liquid metal wire, where the insulating block or the groove is located, and at the end of the second liquid metal wire. Combined with the waveform change of the reflected wave of the first liquid metal wire relative to the first baseline, when it is judged that there is a stretching deformation, the position and amount of the stretching deformation generated by the flexible wire can be accurately determined in combination with the reflected wave of the second liquid metal wire, so that the type and characteristics of the deformation (compression position, compression amount, position of the stretched flexible unit, number of stretched flexible units, length of each flexible unit after stretching) can be accurately determined.

[0046] Figure 3 A schematic diagram of the structure of a second liquid metal wire provided in the disclosed embodiment, such as Figure 3 As shown in , the second liquid metal wire is composed of a liquid metal conductive core 301 and an outer insulating layer 302. Figure 3 As shown in (a), at fixed intervals inside the second liquid metal wire, the outer insulating layer 302 may be provided with insulating protrusions 303a (for example, insulating blocks may be embedded) protruding toward the liquid metal conductive core 301, and the cross section of the second liquid metal wire includes a cross section 304 and a cross section 305, as shown in FIG. Figure 3 As shown in (b) , the outer insulating layer 302 may also be provided with an insulating groove 303 b , the groove facing away from the liquid metal conductive core 301 , and the cross section of the second liquid metal wire includes the cross section 306 and the cross section 305 .

[0047] It can be understood that the deformation of the first liquid metal wire and the deformation of the second liquid metal wire in the flexible wire are the same. Therefore, if the number of peaks reflected by the first liquid metal wire has not increased relative to the first baseline waveform, and the number of peaks reflected by the second liquid metal wire has not increased relative to the second baseline waveform, then no compression has occurred. The time difference between the peaks reflected by the second liquid metal wire can be combined to determine the tensile deformation characteristics of the flexible wire, which can include uniform tensile deformation (tensile deformation occurs throughout the flexible wire) and distributed tensile deformation (non-uniform deformation, such as tensile deformation occurring at multiple different locations).

[0048] It can be understood that in the embodiment of the present disclosure, if the number of peaks of the reflected wave of the first liquid metal wire increases relative to the number of peaks of the first baseline waveform, and the number of peaks and the position of the peaks increased by the reflected wave of the second liquid metal wire relative to the second baseline waveform are the same as those increased by the first liquid metal wire, then the position of the newly increased peak of the reflected wave of the first liquid metal wire relative to the baseline corresponds to the position of the flexible wire, and the peak at the same position in the reflected wave of the second liquid metal wire is also caused by compression deformation, and then the remaining peaks of the second liquid metal wire are all unrelated to the compression deformation. The remaining peaks are the peaks corresponding to the starting end of the second liquid metal wire, the location of the insulating block or the groove, and the end of the second liquid metal wire. The characteristics of the tensile deformation can be determined according to the change in the time difference between the remaining peaks.

[0049] It should be noted that in the embodiments of the present disclosure, for ease of explanation, the experimental data is described by taking the flexible insulator as an embedded insulating block (protrusion) on the flexible insulating layer, the parameters of each embedded insulating block are the same, and the lateral distribution of the embedded insulating blocks in the flexible wire is uniform.

[0050] In the disclosed embodiment, the signal transceiver periodically transmits a step electromagnetic waveform or a pulse electromagnetic waveform to the first liquid metal wire and the second liquid metal wire synchronously, and synchronously receives and records the electromagnetic waveform reflected by the first liquid metal wire and the second liquid metal wire. The controller compares the waveform characteristics of the baseline wave and the reflected wave in the first liquid metal wire and the baseline wave and the reflected wave in the second liquid metal wire respectively to determine whether deformation occurs on the flexible guide wire, and determines that the flexible wire is deformed when the waveform characteristics change. The controller determines the deformation type and deformation position of the flexible wire by analyzing the changes of the reflected wave in the first liquid metal and the reflected wave in the second liquid metal relative to their respective baseline waveforms.

[0051] Optionally, in an embodiment of the present disclosure, based on the flexible distributed strain sensor of the above structure, the embodiment of the present disclosure proposes a deformation measurement method.

[0052] Figure 4 A flow chart of a deformation measurement method provided by an embodiment of the present disclosure is shown in FIG. Figure 4 As shown in , the flexible distributed strain sensor can perform deformation measurement according to the following methods S401 to S403:

[0053] S401. In an initial state, a signal transceiver transmits a test waveform to a first liquid metal wire and a second liquid metal wire, and receives reflected waveforms of the first liquid metal wire and the second liquid metal wire, and a controller determines a baseline waveform according to the reflected waveforms.

[0054] In practical applications, surveyors can arrange the flexible wires of the flexible distributed strain sensor at the location to be monitored, such as buried in the soil layer on the hillside or buried in the mountain. After the arrangement is completed, the signal transceiver can be controlled to transmit electromagnetic waves to the two wires of the flexible wire. The controller receives the reflected waves reflected in the two wires through the signal transceiver to obtain the baseline waveform in advance, so as to determine the type and location of deformation based on the baseline waveform and the reflected waveform of the monitoring process in the subsequent monitoring process.

[0055] Optionally, after the flexible conductor is deformed once, if the stress disappears or the stress stabilizes, the controller may re-determine the baseline waveform of the flexible conductor to facilitate subsequent deformation monitoring.

[0056] S402: The signal transceiver periodically transmits a test waveform to the flexible wire, and receives reflected waveforms of the first liquid metal wire and the second liquid metal wire.

[0057] It can be understood that the signal transceiver can periodically and synchronously transmit test electromagnetic waves to the first liquid metal wire and the second liquid metal wire in the flexible wire. The test electromagnetic waves are transmitted in the first liquid metal wire and the second liquid metal wire and reflected back to the signal transceiver. The signal transceiver then sends the reflected waves in the flexible wire to the controller, so that the controller can analyze the deformation of the flexible wire based on the reflected waveform and the baseline waveform.

[0058] S403: The controller determines the deformation position and deformation type of the flexible conductor according to the reflection waveform and the baseline waveform in the measurement period.

[0059] Specifically, the controller may determine the deformation of the flexible wire according to the waveform change characteristics of the reflected wave and the baseline waveform within the measurement period.

[0060] It should be noted that in actual measurements, due to measurement errors and signal changes, the amplitude and position of the reflected wave measured each time will be offset. Therefore, the controller can first locate the reflected wave at the beginning and end of the flexible wire based on the baseline waveform, and then perform waveform change characteristic analysis based on the number of peaks of the reflected wave and the changes in the peak position relative to the baseline waveform.

[0061] The disclosed embodiment provides a flexible distributed strain sensor, which includes two flexible wires of liquid metal transmission wires with different structures, namely, uniform structure and non-uniform structure. Since the reflected wave characteristics of the liquid metal wire with uniform conductive layer structure and the liquid metal wire with variable conductive layer size are different, the signal transceiver can first measure the baseline waveforms of the liquid metal wires with two structures based on the flexible wire, respectively obtain the baseline waveform of the uniform liquid metal wire and the baseline waveform of the non-uniform liquid metal wire, and then periodically send electromagnetic waves to the two structural wires in the flexible wire. The controller receives the waveforms of the two reflected waves and analyzes the characteristics of the two baseline waveforms through docking. Since the characteristics of the reflected waves generated by deformation of the two liquid metal wires with different structures are different, and the flexible wire includes distributed flexible units, it is possible to judge whether deformation occurs on each flexible unit of the flexible wire based on the changes in the reflected waves and baseline waves of the two liquid metal wires, and analyze the type and position of the deformation based on the waveform when deformation occurs. That is, the monitoring accuracy is high, the repeatability is high, and it can monitor a variety of deformation types to provide comprehensive and accurate data, which is of great significance for improving the efficiency of landslide warning in the monitored area, optimizing the structural maintenance plan in the monitored area, and enhancing the overall safety of the system. However, when a traditional flexible wire is stretched and deformed at one position, the flexible wire will deform as a whole, and only the length after the overall stretching can be determined, but the specific position of the stretching deformation cannot be accurately located. That is, if there is tensile stress at multiple discontinuous positions, the traditional flexible wire cannot accurately determine the location of each stretching section and the length of each stretching section, and the accuracy of deformation monitoring is poor. Traditional rigid wires are easily broken under stress, and the accuracy and repeatability of deformation monitoring are poor.

[0062] Optionally, in the initial state, there are peaks at both ends of the first baseline waveform of the first liquid metal wire, and there are peaks at both ends of the second baseline waveform of the second liquid metal wire and at the position where the flexible insulator is provided.

[0063] In the embodiment of the present disclosure, a flexible conductor with uniform material structure made with the following parameters is experimentally verified, wherein the total length of the material of the flexible conductor is 60 cm. The total length of the material of the first liquid metal conductor in the flexible conductor is 60 cm, the total diameter is 2 mm, the diameter of the liquid metal conductive core 201 of the first liquid metal conductor is 1 mm, the thickness of the outer insulating layer 202 of the first liquid metal conductor is 1 mm, and the outer insulating layer 202 is made of silicone Ecoflex 00-30. The total length of the material of the second liquid metal wire is 60 cm. Compared with the first liquid metal wire, the liquid metal conductive core of the second liquid metal wire is inlaid with three insulating blocks, that is, three insulating blocks are inlaid at the 20 cm position, the 40 cm position and the 60 cm position. The second liquid metal wire is divided into three units, namely the first unit, the second unit and the third unit, each unit is 20 cm long, and the material of the insulating block can be silica gel PDMS (Polydimethylsiloxane), and the cross-sectional area of ​​the insulating block accounts for 30% of the cross-sectional area of ​​the liquid metal core of the second liquid metal wire.

[0064] It should be noted that the transmission line of electromagnetic waves in the conductor is related to the material of the external insulating shell. In the embodiment of the present disclosure, a flexible conductor with a length of 60 cm is prepared based on the above-mentioned example parameters. According to the actual length measured after preparation, the time difference between the wave peak at the starting end and the wave peak at the end is tested. According to the following formula (1), the transmission speed of electromagnetic waves can be obtained. In the case of the above-mentioned flexible conductor made of Ecoflex00-30 material, the transmission speed of electromagnetic waves in the flexible conductor is 1.2×10 8 m / s.

[0065] For example, Figure 5 A schematic diagram of a baseline waveform of a flexible wire provided in an embodiment of the present disclosure, Figure 5 (a) is the first baseline waveform corresponding to the first liquid metal wire. Figure 5 (b) in the figure is the second baseline waveform corresponding to the second liquid metal wire. Figure 5 In (a), the peak A1 in the reflected wave is the peak reflected from the beginning of the first liquid metal wire, and the peak A2 is the peak reflected from the end of the first liquid metal wire. The time difference between the two peaks is 10.1 ns (nanoseconds). According to formula (1) and the electromagnetic wave transmission speed of 1.2×10 8 m / s, it can be calculated that the actual length of the first liquid metal wire is 60.6 cm. Figure 5In (b), peaks B1, B2, B3 and B4 are respectively the peaks reflected by the start of the second liquid metal wire, the first insulating block, the second insulating block and the end of the second liquid metal wire (also the location of the third insulating block). The time difference between peaks B1 and B2 is 3.1ns, the time difference between peaks B2 and B3 is 4ns, and the time difference between peaks B3 and B4 is 3.2ns. According to formula (1), it can be calculated that the actual length of the second liquid metal wire is 61.8cm, the distance between the start and the first insulating block is 18.6cm, the distance between the first insulating block and the second insulating block is 24cm, and the distance between the second insulating block and the end is 19.2cm.

[0066] Optionally, in the flexible distributed strain sensor provided in the embodiment of the present disclosure, the above S403 may be specifically performed by the following S403a:

[0067] S403a: If the first reflected waveform is the same as the first baseline waveform, and the second reflected waveform is the same as the second baseline waveform, the controller determines that the flexible wire is not deformed.

[0068] The first reflected waveform is a reflected waveform of the first liquid metal wire, and the second reflected waveform is a reflected waveform of the second liquid metal wire.

[0069] It can be understood that if the first liquid metal wire and the second liquid metal wire are not deformed, the overall waveform length and the number of peaks in the monitored reflection waveform will not change.

[0070] It should be noted that, in theory, the overall waveform reflected by the flexible wire under monitoring does not change, but in actual measurement, due to environmental changes, measurement errors, signal transmission attenuation, etc., the amplitude of the reflected wave reflected by the flexible wire may change, and the overall position of the peak of the reflected wave may shift. That is, in actual use, the same waveform in the embodiment of the present disclosure means that the number of peaks, the time difference between adjacent peaks, and the time difference between the first and last peaks do not change within the measurement error range.

[0071] Based on this solution, when it is monitored that the waveform of the first liquid metal wire (uniform wire) has not changed and the waveform of the second liquid metal wire (non-uniform wire) has not changed, the controller can determine that the flexible wire has not been deformed before this measurement cycle.

[0072] Optionally, in the flexible distributed strain sensor provided by the embodiment of the present disclosure, the above S403 may be specifically performed by the following S403b1, S403b2 or S403b3:

[0073] S403b1. If the number of wave peaks of the first reflected waveform is the same as the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is greater than the time length of the first baseline waveform, the controller determines that the flexible wire does not undergo compression deformation but undergoes tension deformation.

[0074] S403b2: If the number of wave peaks of the first reflected waveform is different from the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is equal to the time length of the first baseline waveform, the controller determines that the flexible wire undergoes compression deformation but not tension deformation.

[0075] S403b3: If the number of wave peaks of the first reflected waveform is different from the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is different from the time length of the first baseline waveform, the controller determines that the flexible wire undergoes compression deformation and tension deformation.

[0076] It can be understood that the first liquid metal wire is a wire with a uniform conductive layer. If the first liquid metal wire undergoes a compression deformation, the electromagnetic wave transmitted in the first liquid metal wire will reflect a peak, and the overall transmission time of the electromagnetic wave remains unchanged. If the first liquid metal wire undergoes a tensile deformation, the electromagnetic wave transmitted in the first liquid metal wire will not reflect the peak, but the total transmission time of the electromagnetic wave will increase. The second liquid metal wire is a wire with an uneven conductive layer size. If a compression deformation occurs on the flexible unit of the second liquid metal wire, a reflection peak will be added. If the compression deformation occurs on the insulator, the reflection peak will not be added, and the overall transmission time of the electromagnetic wave remains unchanged. Therefore, based on the comparison of the peaks reflected by the two types of liquid metal wires in the flexible wires in the embodiments of the present disclosure, the deformation characteristics can be specifically determined.

[0077] Based on this solution, in some practical application scenarios, when it is only necessary to determine the type of deformation that has occurred, it is possible to quickly determine whether the flexible wire has undergone compression deformation and tension deformation based on the change in the number of peaks of the first test waveform relative to the first baseline waveform. When the number of peaks changes, the flexible wire has undergone compression deformation; when the waveform length changes, the flexible wire has undergone tension deformation; when both the number of peaks and the waveform length change, the flexible wire has undergone compression and tension deformation, thereby quickly locating the type of deformation.

[0078] Optionally, in the flexible distributed strain sensor provided by the embodiment of the present disclosure, the above S403 may be specifically performed by the following S403c1 and S403c2:

[0079] S403c1. If the first reflected waveform and the first baseline waveform have the same time length, and the first reflected waveform has K additional peaks compared to the first baseline waveform, the controller determines that the K additional peaks all correspond to K compression deformations.

[0080] It can be understood that if the time lengths of the first reflection waveform and the first baseline waveform are equal, it is determined that the first liquid metal wire has not undergone tensile deformation. Since the deformation of the first liquid metal wire is the same as the deformation of the second liquid metal wire, the second liquid metal wire has not undergone tensile deformation either. Therefore, the newly added K peaks correspond to the compressive deformation at point K of the flexible wire.

[0081] Specifically, the flexible units where the K compression deformations are located can be roughly located based on the percentage of the time positions corresponding to the newly added K wave peaks in the total waveform.

[0082] S403c2. The controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire according to the time difference between each of the K peaks and the first end peak of the first reflected waveform, and determines the K compression positions of the first liquid metal wire.

[0083] It should be noted that the peak distribution on the waveform reflected back by the flexible wire corresponds to the position distribution of the head end, the flexible insulator, the compression position, the stretching position and the end of the flexible wire.

[0084] Based on this scheme, after determining that the flexible wire has only undergone compression deformation, and after determining the number of positions where the flexible wire is compressed based on the waveform reflected by the first liquid metal wire and the first baseline waveform, the precise position where the flexible wire is compressed can be quickly determined based on the time difference between the peaks of the reflected wave, that is, the flexible unit where the compression is located, as well as the distance of the compression from the starting end of the flexible wire can be located. In the case of compression deformation, the type and characteristic information of the compression deformation can be accurately and quickly determined.

[0085] Optionally, in the flexible distributed strain sensor provided by the embodiment of the present disclosure, the above S403 may be specifically performed by the following S403d:

[0086] S403d, the controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire based on the time difference between the i-th peak and the first end peak of the first reflected waveform and formula (1), so as to determine each position where the flexible wire undergoes compression deformation.

[0087] Formula (1)

[0088] in, represents the length from the i-th wave crest among the K wave crests from the corresponding position of the first liquid metal wire to the starting end of the first liquid metal wire, i is an integer greater than or equal to 1 and less than or equal to K, represents the time difference between the i-th peak and the beginning of the first peak, Represents the propagation speed of electromagnetic waves in flexible conductors.

[0089] It should be noted that the optical cable speed factor is related to the material of the flexible casing of the flexible conductor. is the propagation speed of electromagnetic waves in flexible conductors.

[0090] It should be noted that the propagation speed of electromagnetic waves in flexible conductors is related to the insulating material of the flexible conductors. The optical cable speed factors of different insulating materials are different. The optical cable speed factor is a positive number less than 1, that is, different insulating materials have different attenuations on the propagation speed of electromagnetic waves.

[0091] In the embodiment of the present disclosure, the above calculation method is only an exemplary description provided by the embodiment of the present disclosure. In actual applications, the distance between the flexible wires corresponding to the two adjacent peaks can also be calculated based on the time difference between the two adjacent peaks. After calculating the distance between the previous peak of the first peak and the first peak, the distance between the flexible wires corresponding to the two adjacent peaks can be calculated, thereby calculating the distance between the first peak and the flexible wires corresponding to the first peak.

[0092] Based on this scheme, after determining the peak corresponding to the compression deformation, the controller can accurately determine the distance between each compression deformation position and the starting end of the first liquid metal wire based on the time difference between each compression deformation peak and the peak of the starting end of the first liquid metal wire and based on the above-mentioned calculation method.

[0093] Optionally, in the flexible distributed strain sensor provided by the embodiment of the present disclosure, the above S403 may specifically include the following S403d2 execution:

[0094] S403d2. After determining the compression position based on the first liquid metal wire, the controller determines the peak generated by the flexible insulator in the second reflection waveform based on the second reflection waveform, and determines the characteristics of the tensile deformation according to the target time difference in the second reflection waveform and the time difference between two adjacent peaks in the second baseline waveform.

[0095] The target time difference includes: the time difference between the starting end peak and the peak corresponding to the first flexible insulator, the time difference between the peaks corresponding to every two adjacent flexible insulators, and the time difference between the peak corresponding to the last flexible insulator and the end peak.

[0096] Specifically, after determining the wave peak corresponding to the compression deformation based on the reflected wave of the first liquid metal wire, the wave peaks corresponding to the first and last ends and the wave peaks generated by compression can be removed based on the comparison between the second reflected waveform and the first reflected waveform, and the remaining wave peaks can be determined as the wave peaks generated by each flexible insulator. Furthermore, based on the time difference between the wave peaks of the flexible insulator and the time difference between the wave peaks of the flexible insulator and the starting and ending ends, the stretching condition of each flexible unit can be determined.

[0097] Based on this scheme, when the flexible wire only undergoes compression deformation, after locating the compression position of the flexible wire based on the baseline waveform and the reflected waveform of the first liquid metal wire, the peak generated by the flexible insulator and the position of the peak can also be accurately located based on the waveform reflected by the second liquid metal wire and the waveform reflected by the first liquid metal wire, thereby determining the specific characteristics of the tensile deformation.

[0098] Optionally, in the flexible distributed strain sensor provided by the embodiment of the present disclosure, the above S403 may specifically include the following S403e1 and S403e2:

[0099] S403e1. If the first reflected waveform and the first baseline waveform have the same number of peaks and different total durations, and the second reflected waveform and the second baseline waveform have the same number of peaks and different total durations, the controller determines that no compression deformation occurs but tensile deformation occurs.

[0100] It can be understood that if the number of peaks in the first reflection waveform reflected by the first liquid metal wire and the number of peaks in the first baseline waveform do not change, it means that the first liquid metal wire has not undergone compressive deformation (that is, neither the flexible wire nor the second liquid metal wire has undergone compressive deformation); if the total duration of the waveform reflected by the first liquid metal wire increases relative to the first baseline waveform, it is determined that the first liquid metal wire has undergone tensile deformation (that is, both the flexible wire and the second liquid metal wire have undergone tensile deformation).

[0101] S403e2. The controller determines the characteristics of the tensile deformation according to the time difference between two adjacent peaks in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform.

[0102] In the embodiment of the present disclosure, since the second liquid metal wire is a distributed wire, the stretching position can also be distributed, that is, only the length of the unit can be stretched. After the length of the unit changes, it can cause the size of the metal conductive core of this section to change, and the transmission time of the electromagnetic wave in this section will increase.

[0103] Based on this scheme, when it is determined that only tensile deformation exists based on the changes in the first reflected waveform and the first baseline waveform, the controller can determine the characteristics of the tensile deformation based on the changes in the time difference between two adjacent peaks in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform.

[0104] Optionally, in the flexible distributed strain sensor provided in the embodiment of the present disclosure, the above S403e2 may specifically include the following S403e3 execution:

[0105] S403e3, if , the controller determines that the j-th flexible unit undergoes stretching deformation.

[0106] in, represents the time difference between the jth peak and the j+1th peak in the second reflected waveform, represents the time difference between the j-th peak and the j+1-th peak in the second baseline waveform, where j is a positive integer less than or equal to M+1.

[0107] It can be understood that after determining that only tensile deformation exists based on the waveform comparison of the reflected wave of the first liquid metal wire and the first baseline wave, it is possible to compare the first time difference between the two peaks on the second reflected waveform corresponding to each flexible unit of the second liquid metal wire and the second time difference between the two peaks on the second baseline waveform, so as to determine whether the section of the flexible wire has tensile deformation. When the first time difference and the second time difference are the same, the section of the flexible unit has not undergone tensile deformation. When the first time difference is greater than the second time difference, tensile deformation has occurred on the section of the flexible unit. Then, the length after stretching and the length obtained by stretching are determined based on the propagation speed of the electromagnetic wave and the time difference of the peaks of the flexible unit.

[0108] Based on this solution, when only tensile deformation occurs, the flexible unit that is stretched and the stretching length of each flexible unit can be quickly and accurately located based on the time difference between the corresponding peaks in the second baseline waveform and the second reflection waveform corresponding to the second liquid metal wire.

[0109] Example

[0110] It should be noted that in order to accurately verify the accuracy of deformation measurement based on the flexible distributed strain sensor provided in the embodiment of the present disclosure, a known deformation can be accurately applied to the flexible wire, and deformation analysis can be performed based on the waveform according to the measurement method provided in the above embodiment to determine whether the analysis result matches the known deformation.

[0111] Example 1: Known deformation applied to a flexible wire: The first unit of the flexible wire is stretched by 20 cm, the third unit is stretched by 20 cm, and after stretching, a compressive deformation is applied at a distance of 40 cm from the starting end of the flexible wire.

[0112] Figure 6 A waveform diagram of a monitored reflected wave provided by an embodiment of the present disclosure, such as Figure 6 As shown in (a), the controller detects that the reflected wave in the first liquid metal wire after the flexible wire is deformed includes three peaks, namely, peak C1, peak C2 and peak C3. Figure 6 As shown in (b), the controller monitors that after the flexible wire is deformed, the reflected wave after the second liquid metal wire is deformed includes four peaks, namely peak D1, peak D2, peak D3 and peak D4.

[0113] Step a1: Locate the position of compression deformation.

[0114] Combined with the deformation judgment method provided in the embodiment of the present disclosure, combined with Figure 5 The first baseline waveform shown in (a) and Figure 6 As shown in the first reflection waveform of the first liquid metal wire in (a), the position peak C1 of the first reflection waveform is the peak reflected at the starting end, and the peak C3 is the peak reflected at the end. Compared with the case without deformation, the first reflection waveform of the first liquid metal wire has a new peak C2. Therefore, there is a compression deformation at the position of the flexible wire corresponding to the peak C2, wherein the time difference between the peak C1 and the peak C2 is 6.4ns. According to the above formula (1), it can be determined that the distance between the peak C2 and the starting end is 38.4cm, and the time difference between the peak C1 and the peak C3 is 16.3ns. According to the above formula (1), it can be determined that the distance of the flexible wire between the peak C1 and the peak C3 is 97.8cm.

[0115] Step a2: Determine the characteristics corresponding to each peak.

[0116] like Figure 5 The second baseline waveform shown in (b) and Figure 6 As shown in the second reflected waveform of the second liquid metal wire in (b), peak D1 is the peak generated at the beginning of the second liquid metal wire, peak D4 is the peak generated at the end of the second liquid metal wire, and the remaining peaks are generated by compression deformation and embedded insulating blocks. The time difference between peak D1 and peak D2 is 6.3ns, the time difference between peak D2 and peak D3 is 3.6ns, and the time difference between peak D3 and peak D4 is 6.3ns. Compared with the reflected wave of the first liquid metal wire, peak D2 is generated by compression deformation and the first embedded insulating block, and peak D3 is generated by the second embedded insulating block.

[0117] Step a3: Positioning stretching deformation.

[0118] According to formula (1), the distance between the peaks D1 and D2 is 37.8 cm, the distance between the peaks D2 and D3 is 21.6 cm, and the distance between the peaks D3 and D4 is 38.4 cm. Therefore, the first unit is stretched by 17.8 cm, the second unit is not stretched, and the third unit is stretched by 18.4 cm. There is also compression deformation on the first mosaic block.

[0119] It should be noted that if the flexible wire is only composed of the first liquid metal wire, Figure 6In (a), it can be analyzed that the flexible wire as a whole has a tensile deformation of 37.8 cm, and a compressive deformation has occurred at 38.4 cm from the starting end, which is inconsistent with the non-uniform tensile deformation actually applied to the flexible wire. Therefore, if the flexible wire is only composed of the first liquid metal wire, it is difficult to determine the characteristics of the tensile deformation.

[0120] It should be noted that if the flexible wire is only composed of the second liquid metal wire, Figure 6 As can be seen from (b) in the figure, the first unit is stretched by 17.8 cm, the second unit is not stretched, and the third unit is stretched by 18.4 cm. Figure 6 (b) in the figure cannot determine whether compression deformation occurs at the location where the embedded insulating block is located, so the deformation behavior cannot be accurately determined.

[0121] Example 2:

[0122] The deformation parameters applied to the flexible conductor are: the first unit is stretched by 20 cm, and a compression deformation is applied at a distance of 20 cm from the starting end.

[0123] Figure 7 A schematic diagram of a reflected wave of a flexible wire provided in an embodiment of the present disclosure, such as Figure 7 As shown in (a), the reflected wave generated by the first liquid metal wire is monitored to include three peaks, namely peak E1, peak E2 and peak E3. Compared with the first baseline waveform, one peak is added, so the flexible wire has a compression deformation.

[0124] Step b1: Locate the position of compression deformation.

[0125] Will Figure 7 (a) and Figure 6 Compared with (a), it can be determined that peak E1 is the peak generated at the beginning of the first liquid metal wire, peak E3 is the peak generated at the end of the first liquid metal wire, and peak E2 is the peak caused by compression. The time difference between peak E1 and peak E2 is 3.3ns. According to the formula, it can be calculated that the distance between the compression position of the flexible wire and the beginning of the flexible wire is 19.8cm, and the time difference between peak E1 and peak E3 is 14.1ns. The calculated distance between the beginning and the end of the flexible wire is 84.6cm.

[0126] Step b2: Analyze the characteristics of each peak.

[0127] Figure 7 As shown in (b), the reflected wave reflected by the second liquid metal wire includes 5 peaks. Figure 5In the second baseline waveform shown in (b), peak F1 is the peak generated at the beginning of the second liquid metal wire, and peak F5 is the peak generated at the end of the second liquid metal wire. Therefore, peaks F2, F3, and F4 are peaks generated by compression deformation and embedded insulating blocks. The time difference between peaks F1 and F2 is 3.4ns, the time difference between peaks F2 and F3 is 3.5ns, the time difference between peaks F3 and F4 is 3.1ns, and the time difference between peaks F4 and F5 is 3.6ns. Figure 7 The peak E2 determined in (a) is caused by compression deformation. Therefore, the peak F2 is caused by compression deformation, and the peaks F3 and F4 are caused by the embedded insulating blocks.

[0128] Step b3: Analyze the tensile deformation.

[0129] According to the formula, it can be determined that the distance between the peaks F1 and F2 corresponding to the flexible wire is 20.4cm, the distance between the peaks F2 and F3 corresponding to the flexible wire is 21cm, the distance between the peaks F3 and F4 corresponding to the flexible wire is 18.6cm, and the distance between the peaks F4 and 5 corresponding to the flexible wire is 21.6m. Therefore, the deformation of the flexible wire can be determined as follows: the first unit is stretched by 21.4cm, and compression deformation occurs at a distance of 20.4cm from the starting end, and the second and third units are not deformed, which is consistent with the actual deformation (the first unit is stretched by 20cm and compression deformation is applied at a distance of 20cm from the starting end).

[0130] It can be understood that if the flexible wire is only composed of the first liquid metal wire, Figure 7 From (a) in the figure, it can be seen that the flexible wire as a whole has undergone a tensile deformation of 21.6 cm, and at the same time, compression has occurred at a distance of 19.8 cm from the starting end. This is inconsistent with the fact that the flexible wire has actually undergone non-uniform tensile deformation. Therefore, if the flexible wire is only composed of the first liquid metal wire, it is difficult to accurately determine the characteristics of the tensile deformation.

[0131] If the flexible wire is only composed of the second liquid metal wire, Figure 7 (b) in the figure can be used to infer various possible deformation scenarios:

[0132] The first case: any one of the peaks F2, F3 and F4 is caused by compression, and the remaining two peaks are caused by the embedded insulating block.

[0133] Case 1-1: The peak F2 is caused by compression deformation, and the first unit is stretched by 21.4 cm, and compression deformation occurs at a distance of 20.4 cm from the starting end.

[0134] Case 1-2: The peak F3 is caused by compression deformation, then the first unit and the third unit are not deformed, the second unit is stretched by 19.6 cm, and compression deformation occurs at a distance of 18.6 cm from the starting end of the second unit.

[0135] Case 1-3: Peak F4 is caused by compression deformation, and the third unit is stretched by 20.2 cm, and compression occurs at a distance of 18.6 cm from the starting end of the third unit.

[0136] Second situation:

[0137] It is impossible to confirm whether compressive strain occurs at the location of the insulating block (if there is compression at the location of the insulating block, it will overlap with the insulating block and be difficult to distinguish), so when the flexible wire is only composed of the second liquid metal wire, the deformation characteristics cannot be accurately determined.

[0138] Therefore, compared with using the first liquid metal wire alone or the second liquid metal wire alone, the reflected wave generated by the flexible wire including the first liquid metal wire and the second liquid metal wire can accurately determine the deformation characteristics of the flexible wire.

[0139] It should be noted that the above examples given in the embodiments of the present disclosure are all for the following scenario: the deformation type is not known in advance, and the deformation behavior of the flexible distributed conductor is determined based on the waveform change. The verification process of each of the above embodiments is as follows: (1) applying different combinations of compression and tension deformation; (2) testing to obtain the reflected waveform, and deriving the deformation behavior based on the transmitted waveform; (3) comparing the consistency between the derived deformation type and the applied deformation, if the consistency is good, the flexible distributed strain sensor functions normally.

[0140] It should be noted that in the embodiments of the present disclosure, since the flexible wire has high ductility and is not easy to break, the above analysis is mainly based on the situation that the flexible wire has not broken.

[0141] Corresponding to the embodiments of the aforementioned method, the present disclosure also provides embodiments of a device and a terminal to which the device is applied.

[0142] The embodiments of the controller disclosed herein can be applied to computer devices, such as servers or terminal devices. The device embodiments can be implemented by software, or by hardware or a combination of software and hardware. Taking software implementation as an example, as a device in a logical sense, it is formed by the processor of the file processing in which it is located reading the corresponding computer program instructions in the non-volatile memory into the memory and running them. From the hardware level, such as Figure 8 As shown, it is a hardware structure diagram of the computer device where the controller of the embodiment of the present disclosure is located. Figure 8In addition to the processor 810, memory 830, network interface 820, and non-volatile memory 840 shown, the server or electronic device where the controller 831 is located in the embodiment may also include other hardware, usually according to the actual function of the computer device, which will not be described in detail.

[0143] Accordingly, the present disclosure further provides a controller, which includes a processor; a memory for storing instructions executable by the processor; wherein the processor is configured to: execute the steps of the deformation measurement method executed by the above-mentioned controller.

[0144] The implementation process of the functions and effects of each module in the above-mentioned device is specifically described in the implementation process of the corresponding steps in the above-mentioned method, which will not be repeated here.

[0145] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only schematic, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the disclosed solution. A person of ordinary skill in the art can understand and implement it without paying creative labor.

[0146] The above describes specific embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0147] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the inventions claimed herein. The present disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not claimed in the present disclosure. The description and examples are to be considered exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0148] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

[0149] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A flexible distributed strain sensor, characterized in that: The flexible distributed strain sensor comprises: a flexible wire, and a signal transceiver connected to the flexible wire and a controller; The flexible wire comprises a first liquid metal wire with a uniform conductive layer size wrapped in a flexible sleeve and a second liquid metal wire with a variable conductive layer size, the first liquid metal wire and the second liquid metal wire are not electrically connected, the second liquid metal wire comprises M+1 segments of flexible units, and a flexible insulator that can cause the conductive layer size to change is included between two adjacent segments of flexible units, the flexible insulator is a protrusion protruding toward the liquid metal, or a groove sunken toward the flexible insulating layer, the flexible insulating layer is the flexible sleeve, and M is a positive integer; In an initial state, the signal transceiver transmits a test waveform to the first liquid metal wire and the second liquid metal wire, and receives reflected waveforms of the first liquid metal wire and the second liquid metal wire, and the controller determines a baseline waveform according to the reflected waveforms; in an initial state, there are peaks at both ends of the first baseline waveform of the first liquid metal wire, and there are peaks at both ends of the second baseline waveform of the second liquid metal wire and at a position where a flexible insulator is provided; The signal transceiver periodically transmits the test waveform to the flexible wire, and receives the reflected waveforms of the first liquid metal wire and the second liquid metal wire; The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in a measurement period.

2. The flexible distributed strain sensor according to claim 1, characterized in that: The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in the measurement period, including: If the first reflected waveform is the same as the first baseline waveform, and the second reflected waveform is the same as the second baseline waveform, then the controller determines that the flexible wire is not deformed; The first reflected waveform is a reflected waveform of the first liquid metal wire, and the second reflected waveform is a reflected waveform of the second liquid metal wire.

3. The flexible distributed strain sensor according to claim 2, characterized in that: The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in the measurement period, including: If the number of wave peaks of the first reflected waveform is the same as the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is greater than the time length of the first baseline waveform, the controller determines that the flexible wire has not been compressed but has been stretched; If the number of wave peaks of the first reflected waveform is different from the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is equal to the time length of the first baseline waveform, the controller determines that the flexible wire has undergone compression deformation but not tension deformation; If the number of wave peaks of the first reflected waveform is different from the number of wave peaks of the first baseline waveform, and the time length of the first reflected waveform is different from the time length of the first baseline waveform, the controller determines that the flexible wire has undergone compression deformation and tension deformation.

4. The flexible distributed strain sensor according to claim 3, characterized in that: The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in the measurement period, including: If the first reflected waveform has K additional peaks compared to the first baseline waveform, the controller determines that the K additional peaks all correspond to compression deformations at K locations; The controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire according to the time difference between each of the K peaks and the first end peak of the first reflected waveform, and determines the K compression positions of the first liquid metal wire.

5. The flexible distributed strain sensor according to claim 4, characterized in that: The controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire according to the time difference between each of the K peaks and the peak of the first end of the first reflected waveform, and determines K compression positions of the first liquid metal wire, including: The controller determines the distance between each compression deformation of the first liquid metal wire and the starting end of the first liquid metal wire based on the time difference between the i-th peak and the first end peak of the first reflected waveform and a first preset formula, so as to determine each position where the compression deformation of the flexible wire occurs; Wherein, the first preset formula is: ; represents the length from the i-th wave peak among the K wave peaks at the corresponding position of the first liquid metal wire to the starting end of the first liquid metal wire, i is an integer greater than or equal to 1 and less than or equal to K, represents the time difference between the ith peak and the first end peak of the first reflected waveform, It represents the propagation speed of electromagnetic waves in the flexible wire.

6. The flexible distributed strain sensor according to claim 5, characterized in that: The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in the measurement period, including: After determining the compressed position based on the first liquid metal wire, the controller determines the peak generated by the flexible insulator in the second reflected waveform based on the second reflected waveform, and determines the characteristics of the tensile deformation according to the target time difference in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform; The target time difference includes, in sequence: the time difference between the starting end peak and the peak corresponding to the first flexible insulator, the time difference between the peaks corresponding to every two adjacent flexible insulators, and the time difference between the peak corresponding to the last flexible insulator and the end peak.

7. The flexible distributed strain sensor according to claim 3, characterized in that: The controller determines the deformation position and deformation type of the flexible wire according to the reflection waveform and the baseline waveform in the measurement period, including: If the first reflected waveform and the first baseline waveform have the same number of peaks and different total durations, and the second reflected waveform and the second baseline waveform have the same number of peaks and different total durations, the controller determines that no compression deformation occurs, but tensile deformation occurs; The controller determines the characteristics of the tensile deformation according to the time difference between two adjacent peaks in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform.

8. The flexible distributed strain sensor according to claim 7, characterized in that: The controller determines the characteristics of the tensile deformation according to the time difference between two adjacent peaks in the second reflected waveform and the time difference between two adjacent peaks in the second baseline waveform, including: like , the controller determines that the j-th segment flexible unit undergoes stretching deformation, where represents the time difference between the jth peak and the j+1th peak in the second reflected waveform, represents the time difference between the j-th peak and the j+1-th peak in the second baseline waveform, where j is a positive integer less than or equal to M+1.

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