Flexible array sensor based on fiber-dielectric material composite

Abstract

The application is a flexible array sensor based on fiber-dielectric material composite, comprising an upper flexible substrate, an upper printed electrode layer, a fiber-dielectric material composite sensing layer, a lower printed electrode layer and a lower flexible substrate; the fiber-dielectric material composite sensing layer comprises a dielectric layer film, an x-axis strain sensing optical fiber, an FBG pressure sensing optical fiber, a y-axis strain sensing optical fiber and a temperature sensing optical fiber; the high-precision measurement capability of the optical fiber sensor is combined with the adaptability of the dielectric material. Three kinds of measurement sensor devices are combined together, relative vertical pressure data is obtained through a high spatial resolution distributed pressure sensor, absolute vertical pressure is measured through the FBG pressure sensing optical fiber, and absolute shear force is measured through the x-axis and y-axis strain sensing optical fibers, so that multi-dimensional force array detection of the film sensor is realized.

Description

Technical Field

[0001] This invention belongs to the field of multimodal measurement of flexible sensors for robots, specifically relating to a flexible sensor based on fiber-dielectric material composite and a method for measuring multimodal parameters. Background Technology

[0002] Modern robots rely on advanced sensing systems to perceive their environment and perform precise tasks. These systems often integrate multiple types of sensors to provide rich data for more comprehensive and accurate environmental perception. Multimodal sensing, including pressure, strain, and temperature, is a key parameter for robots to perceive their environment and perform tasks. However, monitoring physical quantities such as temperature, pressure, and strain often requires combinations of sensors with different types of detection parameters, resulting in complex structures that are inconvenient for robot applications. Fiber optic sensing technology utilizes fiber optic sensors for measurement and monitoring. It uses optical fibers as sensors, measuring physical quantities through the transmission and reflection of light. However, fiber optic sensors struggle to achieve high spatial resolution pressure distribution measurement, failing to meet the robot's need for high spatial resolution distributed pressure sensing. For example, Chinese patent CN113514188A discloses a centimeter-level, low-cost, high spatial resolution quasi-distributed fiber optic pressure sensing system, composed of a weakly reflective fiber optic array including pressure sensing and non-pressure sensing areas. This cannot meet the required spatial resolution for certain robot parts, such as dexterous hands. While existing thin-film array sensors can easily detect high spatial resolution distributed pressure signals, they struggle to simultaneously measure lateral strain and temperature signals. For example, Chinese patent publication number CN116907697A discloses a high-resolution distributed pressure sensor, its preparation method and application, which can be used to achieve high-resolution pressure imaging, but cannot detect strain and temperature signals.

[0003] Therefore, the present invention aims to provide a flexible array sensor based on fiber-dielectric material composite and a method for quantitative measurement of multimodal parameters, enabling the detection of multimodal data through a single sensor, thus enabling robots to have multimodal sensing capabilities to perceive the environment and perform precise tasks. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the technical problem this invention aims to solve is to provide a flexible array sensor based on fiber-dielectric material composite and a method for quantitative measurement of multimodal parameters, so as to realize the simultaneous measurement of physical parameters such as pressure, temperature, and strain through the same sensor element, and to quantitatively measure multimodal physical quantities.

[0005] The technical solution adopted by the present invention to solve the aforementioned technical problem is as follows:

[0006] In a first aspect, the present invention provides a flexible array sensor based on optical fiber-dielectric material composite, comprising an upper flexible substrate 1, an upper printed electrode layer 2, an optical fiber-dielectric material composite sensing layer 3, a lower printed electrode layer 4, and a lower flexible substrate 5.

[0007] The fiber-dielectric composite sensing layer 3 includes a dielectric layer thin film 301, an x-axis strain sensing fiber 302, an FBG pressure sensing fiber 303, a y-axis strain sensing fiber 304, and a temperature sensing fiber 305.

[0008] The upper and lower flexible substrates are made of high-temperature resistant flexible film material; the upper and lower printed electrode layers are printed with stretchable conductive ink; the temperature sensing fiber 305 includes a high-temperature resistant fiber core, a high-temperature resistant cladding wrapped around the fiber core, and a temperature-sensitive material coated on the cladding.

[0009] The x-axis strain sensing fiber 302 and the FBG pressure sensing fiber 303 are combined to form a row fiber. The row fiber is inserted into the dielectric thin film from the x-axis direction and arranged in a row.

[0010] The y-axis strain sensing fiber 304 and temperature sensing fiber 305 are combined to form a column fiber. The column fiber is inserted into the dielectric thin film 301 from the y-axis direction and arranged in b rows. The intersection point of the fiber in row a and row b is recorded as a×b FBG distribution points.

[0011] The upper and lower flexible substrates with printed electrodes and the fiber-dielectric composite sensing layer are encapsulated in a sandwich structure. The upper and lower flexible substrates with printed electrodes and the dielectric thin film form a high spatial resolution distributed pressure sensor. The m rows and n columns of printed electrodes intersect each other to form m×n electrode intersection points.

[0012] The distribution points of a×b FBGs partially overlap with the intersection points of m×n electrodes, and the areas covered by both are the same.

[0013] a, b, m, and n are all integers greater than 1, and a is less than m and b is less than n.

[0014] Furthermore, the temperature sensing fiber is resistant to temperatures above 1200℃, the temperature-sensitive material is polyimide, and the measurement temperature range is -30℃ to 120℃; the diameters of the x-axis strain sensing fiber 302 and the y-axis strain sensing fiber 304 are 8 to 900 micrometers.

[0015] Furthermore, the FBG pressure sensing fiber 303 is connected to the FBG demodulator, which quantitatively acquires the pressure and measures the pressure quantitatively.

[0016] The x-axis strain sensing fiber 302, y-axis strain sensing fiber 304, and temperature sensing fiber are all connected to an OFDR fiber optic data acquisition instrument. The strain of the three sensing fibers is measured by the OFDR fiber optic data acquisition instrument to obtain the x-axis shear force, y-axis shear force, and temperature parameters.

[0017] Furthermore, the strain of the temperature-sensing fiber and the strain of the y-axis strain-sensing fiber are detected using an OFDR fiber optic data acquisition instrument, and the current temperature T is obtained according to the following formula:

[0018]

[0019] Where T0 is the initial temperature, Δε T For the strain of the temperature sensing fiber, Δε Y Let a be the strain of the y-axis strain sensing fiber. c E is the coefficient of thermal expansion of temperature-sensitive materials. c and E f These represent the Young's modulus of the temperature-sensitive material and the fiber core of the temperature-sensing optical fiber, respectively. c With A f These are the temperature-sensitive material and the cross-sectional area of ​​the fiber core of the temperature-sensing optical fiber, respectively.

[0020] Secondly, this invention provides a multimodal parameter measurement method, implemented using the aforementioned flexible array sensor based on fiber-dielectric material composite. A high spatial resolution distributed pressure sensor is connected to an embedded microcontroller; an FBG pressure sensing fiber 303 is connected to an FBG demodulator; and x-axis strain sensing fiber 302, y-axis strain sensing fiber 304, and temperature sensing fiber are all connected to an OFDR fiber optic data acquisition instrument. A host computer is connected to the embedded microcontroller, the OFDR fiber optic data acquisition instrument, and the FBG demodulator, respectively. The steps of the measurement method are as follows:

[0021] 1) Z-axis pressure detection

[0022] Start the host computer and embedded microcontroller, and set the sampling frequency of the embedded microcontroller and the data storage mode of the host computer to continuous storage; apply the z-axis pressure feature to a flexible array sensor based on fiber-dielectric composite material, and each frame of its output signal contains m×n z-axis relative pressure data, which constitute the z-axis relative pressure matrix F. rp Simultaneously, the FBG pressure sensing fiber optic unit quantitatively acquires the absolute pressure along the z-axis using an FBG demodulator. Each frame of data consists of a×b absolute pressure data points along the z-axis, and the data is stored continuously. The sum of these a×b absolute pressure data points is used as the total pressure F experienced by the flexible array sensor based on the fiber-dielectric composite material. ww ;

[0023] 2) Calculation of absolute pressure along the z-axis

[0024] A z-axis pressure feature is applied to a flexible array sensor based on fiber-dielectric composite material to obtain all FBG distribution points covered within the pressure area of ​​the z-axis pressure feature. The electrode intersection points coinciding with all FBG distribution points covered by the pressure area are then identified. A high spatial resolution distributed pressure sensor is used to obtain the relative pressure F at these electrode intersection points. rp (c,d), the absolute pressure value F along the z-axis at the intersection of each electrode of the entire high spatial resolution distributed pressure sensor is obtained according to the following formula. abs (k, l) represents the high-resolution absolute pressure distribution along the z-axis;

[0025]

[0026] Where C and D are the number of rows and columns of the electrode intersection points that coincide with the FBG distribution points within the pressure area of ​​the z-axis pressure characteristic, respectively, 1≤c≤C≤m, 1≤d≤D≤n; 1≤k≤m, 1≤l≤n;

[0027] 3) X-axis and Y-axis shear force detection

[0028] Start the host computer and OFDR fiber optic data acquisition instrument, and set the host computer's data storage mode to continuous storage; the OFDR fiber optic data acquisition instrument detects the strain values ​​of each row and column of the x-axis and y-axis strain sensing fiber in real time, and then calculates the x-axis and y-axis shear force values ​​based on the strain values ​​and transmits them to the host computer for display;

[0029] 4) Temperature detection

[0030] The strain of the temperature sensing fiber and the strain of the y-axis strain sensing fiber are detected by an OFDR fiber optic data acquisition instrument, and the current temperature T is obtained according to the following formula:

[0031]

[0032] Where T0 is the initial temperature, Δε T For the strain of the temperature sensing fiber, Δε Y Let a be the strain of the y-axis strain sensing fiber. c E is the coefficient of thermal expansion of temperature-sensitive materials. c and E f These represent the Young's modulus of the temperature-sensitive material and the fiber core of the temperature-sensing optical fiber, respectively. c With A f These are the temperature-sensitive material and the cross-sectional area of ​​the fiber core of the temperature-sensing optical fiber, respectively.

[0033] Thirdly, the present invention provides an application of the above-mentioned flexible array sensor based on fiber-dielectric material composite as an electronic skin for robots.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1. High Integration. This invention provides a flexible sensor based on an optical fiber-dielectric material composite array, combining the high-precision measurement capability of optical fiber sensors with the adaptability of dielectric materials to adapt to complex or dynamic measurement environments. By integrating row and column strain sensing fibers, temperature sensing fibers, pressure sensing fibers, and dielectric sensing materials into a single structure, strain, pressure, temperature, and pressure distribution information can be measured with a single sensing layer. The three measurement sensor devices are combined to obtain relative vertical pressure data through a high spatial resolution distributed pressure sensor, measure absolute vertical pressure through an FBG pressure sensing fiber, and measure absolute shear force through x-axis strain sensing fiber 302 and y-axis strain sensing fiber 304, achieving multi-dimensional force array detection by a thin-film sensor.

[0036] 2. Simultaneous measurement of multiple parameters. It can simultaneously measure multiple parameters such as pressure, deformation, and temperature, providing the robot with comprehensive environmental perception capabilities.

[0037] 3. The flexible array sensor based on fiber-dielectric composite uses a fully flexible material, which allows it to be installed on non-flat or moving surfaces of robots. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of a flexible array sensor based on fiber-dielectric material composite.

[0039] Figure 2 This is a schematic diagram of the fiber-dielectric composite sensing layer.

[0040] In the figure: 1. Upper flexible substrate; 2. Upper printed electrode layer; 3. Fiber-dielectric composite sensing layer; 4. Lower printed electrode layer; 5. Lower flexible substrate; 301. Dielectric layer film; 302. X-axis strain sensing fiber; 303. FBG pressure sensing fiber; 304. Y-axis strain sensing fiber; 305. Temperature sensing fiber. Detailed Implementation

[0041] Specific embodiments of the present invention are given below. These specific embodiments are only used to further illustrate the present invention in detail and do not limit the scope of protection of the claims of the present invention.

[0042] This invention is based on a flexible array sensor composed of optical fiber and dielectric material (see...). Figure 1The device includes an upper flexible substrate 1, an upper printed electrode layer 2, an optical fiber-dielectric material composite sensing layer 3, a lower printed electrode layer 4, and a lower flexible substrate 5. The optical fiber-dielectric material composite sensing layer 3 includes a dielectric thin film 301, an x-axis strain sensing fiber 302, an FBG pressure sensing fiber 303, a y-axis strain sensing fiber 304, and a temperature sensing fiber 305. The upper and lower printed electrode layers are printed with stretchable silver chloride conductive ink. The x-axis strain sensing fiber 302 and the y-axis strain sensing fiber 304 are at least one of single-mode fiber, multimode fiber, tight-buffered or tight-packed fiber, with a diameter of 8 to 900 micrometers.

[0043] The upper and lower flexible substrate layers can be made of high-temperature resistant flexible film materials such as TPU, PET, and PI;

[0044] The fiber-dielectric composite sensing layer is formed by interleaving and combining strain sensing fiber (x-axis strain sensing fiber 302 and y-axis strain sensing fiber 304), temperature sensing fiber, FBG pressure sensing fiber and dielectric material layer.

[0045] The x-axis strain sensing fiber 302 and the FBG pressure sensing fiber 303 are combined and inserted into the dielectric thin film from the x-axis direction.

[0046] The y-axis strain sensing fiber 304 and temperature sensing fiber 305 are combined and inserted into the dielectric thin film 301 from the y-axis direction.

[0047] The FBG pressure sensing fiber 303 uses distributed fiber optic sensing technology for demodulation. The intersection of the FBG pressure sensing fiber 303 and the column fiber constitutes the FBG distribution point, which can perform z-axis pressure sensing on each FBG distribution point.

[0048] In this invention, the FBG demodulator calculates the output of the FBG pressure sensing fiber into actual pressure, which can quantitatively measure the pressure at each FBG distribution point. The FBG distribution points of the FBG pressure sensing fiber 303 partially coincide with the electrode intersection points of the upper and lower printed electrode layers. By utilizing the FBG distribution points, the pressure is distributed to the electrode intersection points, achieving higher resolution pressure detection and solving the problem of low pressure calibration accuracy caused by viscoelasticity in array thin film sensors.

[0049] The FBG (Fiber Bragg Grating) pressure sensing fiber 303 is connected to the FBG demodulator, which quantitatively acquires and measures the pressure.

[0050] The x-axis strain sensing fiber 302 and y-axis strain sensing fiber 304 are connected to the OFDR fiber optic data acquisition instrument, and the strain in the x and y directions is measured by the OFDR fiber optic data acquisition instrument.

[0051] The temperature-sensing optical fiber 305 employs a high-temperature resistant fiber core and a high-temperature resistant cladding. Both the core and cladding are primarily composed of silicon dioxide, with a temperature resistance exceeding 1200℃. A temperature-sensitive material is coated onto the entire fiber cladding; in this embodiment, polyimide is used. The measurement temperature range is -30℃ to 120℃. Strain data is acquired using an OFDR fiber optic data acquisition instrument and converted to temperature data via a host computer.

[0052] The temperature-sensing optical fiber 305 consists of an optical fiber core, a cladding covering the surface of the optical fiber core, and a temperature-sensitive material coated on the cladding. When the temperature-sensitive material is wrapped around the optical fiber core, it undergoes a shape change due to contact, and this shape change is applied to the optical fiber core. The fiber strain value is proportional to the amount of temperature change, while the rate of change is determined by the coefficient of thermal expansion and the thickness of the temperature-sensitive material. The relationship is as follows:

[0053]

[0054] Where Δε is the strain exerted on the fiber core by the temperature-sensitive material when the temperature changes, a c E is the coefficient of thermal expansion of temperature-sensitive materials. c and E f These represent the Young's modulus of the temperature-sensitive material of the temperature-sensing optical fiber and the core of the optical fiber under test, respectively. c With A f These represent the cross-sectional areas of the temperature-sensitive material and the fiber core of the temperature-sensing optical fiber, respectively, where ΔT is the temperature change.

[0055] Therefore, the expression for the temperature change ΔT can be obtained as follows:

[0056]

[0057] Furthermore, since the temperature sensing fiber 305 and the y-axis strain sensing fiber 304 are wound together, the y-axis strain changes synchronously with the temperature change. The strain Δε of the y-axis strain sensing fiber is measured by the OFDR fiber optic data acquisition instrument. Y The strain Δε of the temperature sensing fiber T (Including temperature changes and fiber optic cable changes)

[0058] Therefore, the strain of the temperature-sensing fiber is obtained by adding the temperature strain and the y-axis strain. When the temperature changes, the strain Δε exerted by the temperature-sensitive material on the fiber core is Δε = Δε T -△ε Y The current temperature T can then be expressed as:

[0059]

[0060] Where T0 is the initial temperature, and ΔεT For the strain of the temperature sensing fiber, Δε Y The strain of the y-axis strain sensing fiber;

[0061] Temperature changes at FBG distribution points are detected, and the distributed strain of temperature sensing fiber 305 is detected by OFDR fiber optic data acquisition instrument, thereby enabling distributed temperature measurement.

[0062] In this invention, the x-axis strain sensing fiber 302 and y-axis strain sensing fiber 304 are measured using an OFDR fiber optic data acquisition instrument to solve the problem that general flexible thin-film pressure sensors are difficult to measure lateral strain. This invention also constructs a high spatial resolution distributed pressure sensor by combining upper and lower printed electrode layers with a dielectric layer film interspersed with FBG pressure sensing fiber 303, solving the problem of insufficient spatial resolution when measuring pressure with micro-bent pressure sensing fibers. Furthermore, by integrating temperature sensing fiber and strain sensing fiber together, the sensor can simultaneously measure temperature and strain. Fiber optic temperature measurement technology has a significant advantage in the strong electromagnetic fields encountered during robot operation because it has no additional heating caused by conductive parts and is unaffected by electromagnetic interference.

[0063] Example 1

[0064] This embodiment of the multimodal parameter measurement method utilizes a flexible array sensor based on fiber-dielectric material composite. The measurement method includes the following steps:

[0065] The first step is to fabricate a flexible array sensor based on fiber-dielectric material composite;

[0066] First, upper and lower printed electrode layers and dielectric layer films are prepared. Stretchable silver chloride conductive ink is printed onto a TPU film using a custom-made screen printing template to prepare an upper printed electrode layer 2 with 16 rows of electrodes and a lower printed electrode layer 4 with 16 columns of electrodes; the dielectric layer film 301 is prepared by printing ion gel onto a nonwoven fabric.

[0067] Then, the fiber-dielectric composite sensing layer 3 is prepared. The x-axis strain sensing fiber 302 and the FBG pressure sensing fiber 303 are combined side by side to form a row fiber. The row fiber is inserted into the dielectric layer film in a serpentine path from the x-axis direction, and arranged in 8 rows. The y-axis strain sensing fiber and the temperature sensing fiber are combined side by side to form a column fiber. The column fiber is inserted into the dielectric layer film in a serpentine path from the y-axis direction, and arranged in 8 columns. The 8 rows and 8 columns of fibers constitute a fiber array.

[0068] Finally, the upper and lower flexible substrates with printed electrodes and the fiber-dielectric composite sensing layer are encapsulated in a sandwich structure to fabricate a flexible array sensor based on fiber-dielectric composite. The upper and lower flexible substrates with printed electrodes and the dielectric thin film constitute a high spatial resolution distributed pressure sensor. Eight rows and eight columns of optical fibers intersect to form 8×8 fiber intersections, and 16 rows and sixteen columns of printed electrodes intersect to form 16×16 electrode intersections. The coverage area of ​​the 8×8 fiber intersections is the same as that of the 16×16 electrode intersections, establishing a connection between the 8×8 fiber intersections and the 16×16 electrode intersections to achieve high spatial resolution distributed pressure display.

[0069] Step 2: Data collection;

[0070] (1) The electrode input and output ports of the high spatial resolution distributed pressure sensor are connected to the STM32 embedded microcontroller. The STM32 embedded microcontroller collects data and displays the pressure cloud map through the host computer. The sampling frequency of the STM32 embedded microcontroller is set to 100Hz. Each frame of data is 16×16 pressure data. The data storage method is continuous storage.

[0071] (2) The x-axis and y-axis strain sensing optical fibers are connected to the OFDR optical fiber data acquisition instrument, which collects the data at a sampling frequency of 100Hz. Each frame contains 16 x-axis and y-axis strain data, and the data is stored continuously. The OFDR optical fiber data acquisition instrument is also connected to the host computer to display the strain changes in the x and y directions.

[0072] (3) The FBG pressure sensing fiber is connected to the FBG demodulator. The FBG demodulator quantitatively collects the pressure. Each frame of data consists of 8×8 z-axis absolute pressure data. The data is stored continuously.

[0073] (4) The temperature sensing fiber is also connected to the OFDR fiber optic data acquisition instrument, which collects data at a sampling frequency of 100Hz. Each frame contains 64 strain data points, and the data is stored continuously.

[0074] Step 3: Calculate the multimodal parameters;

[0075] 1) Z-axis pressure detection

[0076] Start the host computer and embedded microcontroller, and set the sampling frequency of the embedded microcontroller and the data storage mode of the host computer to continuous storage. Apply z-axis pressure characteristics to a flexible array sensor based on fiber-dielectric composite material. Each frame of its output signal contains 16×16 z-axis relative pressure data, and the 16×16 z-axis relative pressures constitute the z-axis relative pressure matrix F. rpSimultaneously, the FBG pressure sensing fiber optic cable quantitatively acquires the absolute pressure along the z-axis using an FBG demodulator. Each frame of data consists of 8×8 z-axis absolute pressure data points, stored continuously. The sum of these 8×8 z-axis absolute pressure data points is used as the total pressure F experienced by the flexible array sensor based on the fiber-dielectric composite material. ww ;

[0077] 2) Calculation of absolute pressure along the z-axis

[0078] A z-axis pressure feature is applied to a flexible array sensor based on fiber-dielectric composite material to obtain all FBG distribution points covered within the pressure area of ​​the z-axis pressure feature. The electrode intersection points coinciding with all FBG distribution points covered by the pressure area are then identified. A high spatial resolution distributed pressure sensor is used to obtain the relative pressure F at these electrode intersection points. rp (c,d), the absolute pressure value F along the z-axis at the intersection of each electrode of the entire high spatial resolution distributed pressure sensor is obtained according to the following formula. abs (k, l) represents the high-resolution absolute pressure distribution along the z-axis;

[0079]

[0080] Where C and D are the number of rows and columns of the electrode intersection points that coincide with the FBG distribution points within the pressure area of ​​the z-axis pressure characteristic, respectively, 1≤c≤C≤m, 1≤d≤D≤n; 1≤k≤m, 1≤l≤n;

[0081] This allows for a 16×16 absolute pressure distribution along the z-axis;

[0082] 3) X-axis and Y-axis shear force detection

[0083] Start the host computer and OFDR fiber optic data acquisition instrument, and set the host computer's data storage mode to continuous storage; the OFDR fiber optic data acquisition instrument detects the strain values ​​of each row and column of the x-axis and y-axis strain sensing fiber in real time, and then calculates the x-axis and y-axis shear force values ​​based on the strain values ​​and transmits them to the host computer for display;

[0084] 4) Temperature detection

[0085] The strain of the temperature sensing fiber and the strain of the y-axis strain sensing fiber are detected by an OFDR fiber optic data acquisition instrument, and the current temperature T is obtained according to the following formula:

[0086]

[0087] Where T0 is the initial temperature, Δε T For the strain of the temperature sensing fiber, Δε Y Let a be the strain of the y-axis strain sensing fiber.c E is the coefficient of thermal expansion of temperature-sensitive materials. c and E f These represent the Young's modulus of the temperature-sensitive material and the fiber core of the temperature-sensing optical fiber, respectively. c With A f These are the temperature-sensitive material and the cross-sectional area of ​​the fiber core of the temperature-sensing optical fiber, respectively.

[0088] In this invention, the absolute pressure values ​​at the intersection points of the FBG pressure sensing fiber and its intersecting fibers are obtained using an FBG demodulator. This is a low-resolution z-axis absolute pressure. The sum of the z-axis absolute pressures at the intersection points of all fiber rows and columns represents the total pressure experienced by the flexible array sensor based on the fiber-dielectric composite. The total pressure measured by the FBG pressure sensing fiber is distributed to a 16×16 array of high spatial resolution distributed pressure sensors. The centroid movement distance of the pressure matrix is ​​calculated based on the high-resolution z-axis absolute pressure, which is used for subsequent detection of robot-related parameters.

[0089] In this invention, the OFDR fiber optic data acquisition instrument is a multi-channel OFDR fiber optic data acquisition instrument.

[0090] Example 2

[0091] The fabrication process of a flexible array sensor based on fiber-dielectric material composite is as follows:

[0092] 1) First, upper and lower printed electrode layers and dielectric film are prepared. Stretchable conductive ink is printed onto a flexible substrate using a screen printing template to prepare an upper printed electrode layer with m rows of electrodes and a lower printed electrode layer with n columns of electrodes. The printed electrodes are stretchable flexible electrodes. The dielectric film is obtained by printing ion gel onto a nonwoven fabric.

[0093] 2) Then, a fiber-dielectric composite sensing layer is prepared. The x-axis strain sensing fiber and the FBG pressure sensing fiber are combined and arranged in row a, and inserted into the dielectric layer film from the x-axis direction. The FBG distribution points and the electrode intersection points partially coincide. The y-axis strain sensing fiber and the temperature sensing fiber are combined and arranged in column b, and inserted into the dielectric layer film from the y-axis direction.

[0094] 3) Finally, the upper and lower flexible substrates with printed electrodes and the fiber-dielectric composite sensing layer are encapsulated in a sandwich structure to fabricate a flexible array sensor based on fiber-dielectric composite materials. The upper and lower flexible substrates with printed electrodes and the dielectric thin film constitute a high spatial resolution distributed pressure sensor. The m rows and n columns of printed electrodes intersect to form m×n intersection points, achieving high spatial resolution distributed pressure display. The high spatial resolution distributed pressure sensor operates on the capacitance principle, and temperature has a relatively small impact on its pressure measurement. In contrast, piezoresistive sensors are greatly affected by temperature, making it difficult to simultaneously measure temperature and pressure.

[0095] Example 3

[0096] (1) The m-row n-column high spatial resolution distributed pressure sensor collects data by an embedded microcontroller and displays the pressure cloud map through a host computer. The sampling frequency of the embedded microcontroller is set to p Hz, each frame of data is m×n pressure data, and the data is stored continuously.

[0097] (2) The x-axis and y-axis strain sensing optical fibers are acquired by an OFDR optical fiber data acquisition instrument with a sampling frequency of pHz. Each frame contains c x-axis and y-axis strain data, and the data is stored continuously.

[0098] (3) The FBG pressure sensing fiber is quantitatively collected by the FBG demodulator. Each frame of data consists of a×b pressure data, and the data is stored continuously.

[0099] (4) The temperature sensing fiber is strain acquired by an OFDR fiber optic data acquisition instrument, which includes d temperature strain data, and the data is stored continuously.

[0100] (5) Program the ADC (Analog-to-Digital Converter) module of the embedded microcontroller in the host computer to realize the analog-to-digital conversion of the embedded microcontroller and communication with the host computer. Burn the programmed ADC module project file into the embedded microcontroller using a program burning tool; set the pressure application time; the embedded microcontroller detects the z-axis relative pressure value at the intersection of each electrode row and column of the high spatial resolution distributed pressure sensor in real time.

[0101] (6) Simultaneously, the FBG pressure sensing fiber is used by the FBG demodulator to quantitatively acquire the absolute pressure along the z-axis. Each frame of data consists of a×b absolute pressure data points along the z-axis. The data is stored continuously, and the sum of the a×b absolute pressure data points along the z-axis is used as the total pressure F experienced by the flexible array sensor based on the fiber-dielectric composite. ww ; Total pressure F wwThe pressure is distributed across m×n array points of a high spatial resolution distributed pressure sensor, and the high-resolution z-axis absolute distributed pressure is calculated and displayed on the host computer.

[0102] (7) The OFDR fiber optic data acquisition instrument detects the strain values ​​of each fiber row and column of the x-axis and y-axis strain sensing fiber in real time, and then calculates the x-axis and y-axis shear force values ​​based on the strain values ​​and transmits them to the host computer for display.

[0103] Example 4

[0104] In this embodiment, a flexible array sensor based on fiber-dielectric material composite is applied to a robot as its electronic skin to perform multimodal parameter measurements.

[0105] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A flexible array sensor based on fiber-dielectric material composite, comprising an upper flexible substrate, an upper printed electrode layer, a fiber-dielectric material composite sensing layer, a lower printed electrode layer, and a lower flexible substrate; characterized in that: The fiber-dielectric composite sensing layer includes a dielectric layer film, an x-axis strain sensing fiber, an FBG pressure sensing fiber, a y-axis strain sensing fiber, and a temperature sensing fiber. The upper and lower flexible substrates are made of high-temperature resistant flexible membrane material; The upper and lower printed electrode layers are printed with stretchable conductive ink; the temperature sensing optical fiber includes a high-temperature resistant optical fiber core, a high-temperature resistant cladding wrapped around the optical fiber core, and a temperature-sensitive material coated on the cladding. The x-axis strain sensing fiber and the FBG pressure sensing fiber are combined to form a row fiber. The row fiber is inserted into the dielectric thin film from the x-axis direction and arranged in a row. The y-axis strain sensing fiber and the temperature sensing fiber are combined to form a column fiber. The column fiber is inserted into the dielectric layer film from the y-axis direction and arranged in b rows. The intersection point of the fiber in row a and row b is recorded as a×b FBG distribution points. The upper and lower flexible substrates with printed electrodes and the fiber-dielectric composite sensing layer are encapsulated in a sandwich structure. The upper and lower flexible substrates with printed electrodes and the dielectric thin film form a high spatial resolution distributed pressure sensor. The m rows and n columns of printed electrodes intersect each other to form m×n electrode intersection points. The distribution points of a×b FBGs and the intersection points of m×n electrodes partially overlap, and the areas covered by both are the same. a, b, m, and n are all integers greater than 1, and a is less than m and b is less than n.

2. The flexible array sensor based on fiber-dielectric material composite according to claim 1, characterized in that, The temperature sensing fiber is resistant to temperatures above 1200℃, and the temperature-sensitive material is polyimide. The measurement temperature range is -30℃ to 120℃. The diameters of the x-axis strain sensing fiber and the y-axis strain sensing fiber are 8 to 900 micrometers.

3. The flexible array sensor based on fiber-dielectric material composite according to claim 1, characterized in that, The FBG pressure sensing fiber is connected to the FBG demodulator, which quantitatively acquires and measures the pressure. The x-axis strain sensing fiber, y-axis strain sensing fiber, and temperature sensing fiber are all connected to an OFDR fiber optic data acquisition instrument. The strain of the three sensing fibers is measured by the OFDR fiber optic data acquisition instrument to obtain the x-axis shear force, y-axis shear force, and temperature parameters.

4. The flexible array sensor based on fiber-dielectric material composite according to claim 3, characterized in that, The strain of the temperature sensing fiber and the strain of the y-axis strain sensing fiber are detected by an OFDR fiber optic data acquisition instrument, and the current temperature T is obtained according to the following formula: ， in, The initial temperature, For the strain of temperature sensing optical fiber, The strain of the y-axis strain sensing fiber is... The coefficient of thermal expansion of temperature-sensitive materials, and These refer to the temperature-sensitive material of the temperature-sensing optical fiber and the Young's modulus of the fiber core, respectively. and These are the temperature-sensitive material and the cross-sectional area of ​​the fiber core of the temperature-sensing optical fiber, respectively.

5. A multimodal parameter measurement method, implemented using a flexible array sensor based on fiber-dielectric material composite as described in any one of claims 1-4, characterized in that, A high spatial resolution distributed pressure sensor is connected to an embedded microcontroller; an FBG pressure sensing fiber is connected to an FBG demodulator; x-axis strain sensing fibers, y-axis strain sensing fibers, and temperature sensing fibers are all connected to an OFDR fiber optic data acquisition system; and a host computer is connected to the embedded microcontroller, the OFDR fiber optic data acquisition system, and the FBG demodulator, respectively. The steps of the measurement method are as follows: 1) Z-axis pressure detection Start the host computer and embedded microcontroller, and set the sampling frequency of the embedded microcontroller and the data storage mode of the host computer to continuous storage; apply the z-axis pressure feature to a flexible array sensor based on fiber-dielectric composite material, and each frame of its output signal contains m×n z-axis relative pressure data, which constitute the z-axis relative pressure matrix F. rp Simultaneously, the FBG pressure sensing fiber optic unit quantitatively acquires the absolute pressure along the z-axis using an FBG demodulator. Each frame of data consists of a×b absolute pressure data points along the z-axis, and the data is stored continuously. The sum of these a×b absolute pressure data points is used as the total pressure experienced by the flexible array sensor based on the fiber-dielectric composite material. ; 2) Calculation of absolute pressure along the z-axis A z-axis pressure feature is applied to a flexible array sensor based on fiber-dielectric composite material to obtain all FBG distribution points covered within the pressure area of ​​the z-axis pressure feature. The electrode intersection points coinciding with all FBG distribution points covered by the pressure area are then identified. A high spatial resolution distributed pressure sensor is used to obtain the relative pressure at these electrode intersection points. The absolute pressure value F along the z-axis at the intersection of each electrode of the entire high spatial resolution distributed pressure sensor is obtained according to the following formula. abs This refers to the high-resolution absolute pressure distribution along the z-axis. ， Where C and D are the number of rows and columns, respectively, of the electrode intersection points within the pressure area of ​​the z-axis pressure characteristic that coincide with the FBG distribution points. ; , ; 3) X-axis and Y-axis shear force detection Start the host computer and OFDR fiber optic data acquisition instrument, and set the host computer's data storage mode to continuous storage; the OFDR fiber optic data acquisition instrument detects the strain values ​​of each row and column of the x-axis and y-axis strain sensing fiber in real time, and then calculates the x-axis and y-axis shear force values ​​based on the strain values ​​and transmits them to the host computer for display; 4) Temperature detection The strain of the temperature sensing fiber and the strain of the y-axis strain sensing fiber are detected by an OFDR fiber optic data acquisition instrument, and the current temperature T is obtained according to the following formula: ， in, The initial temperature, For the strain of temperature sensing optical fiber, The strain of the y-axis strain sensing fiber is... The coefficient of thermal expansion of temperature-sensitive materials, and These refer to the temperature-sensitive material of the temperature-sensing optical fiber and the Young's modulus of the fiber core, respectively. and These are the temperature-sensitive material and the cross-sectional area of ​​the fiber core of the temperature-sensing optical fiber, respectively.

6. An application of the flexible array sensor based on fiber-dielectric material composite as described in claim 1, characterized in that, The flexible array sensor based on fiber-dielectric material composite serves as the electronic skin of the robot.

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