Sandwich type braking force measuring device and method based on Bragg grating

Abstract

The invention provides an interlayer type braking force measuring device and method based on a Bragg grating, and relates to the technical field of braking force measurement, and the device comprises a measuring interlayer supporting plate, a temperature change measuring unit, a plurality of deformation measuring units, a transmission optical fiber and a demodulator. The temperature change measuring unit comprises a temperature change measuring Bragg grating and a temperature change measuring optical fiber; each deformation measurement unit internally comprises a deformation assembly, a deformation measurement Bragg grating and a deformation measurement optical fiber, and the deformation measurement Bragg gratings are sequentially connected in series through the deformation measurement optical fibers; the deformation assembly is of a stressed outward deformation structure; the deformation measurement Bragg grating is arranged along a second direction, and the deformation assemblies are fixed in the measurement interlayer support plate; the temperature change measuring unit and the deformation measuring unit are arranged in the measuring interlayer supporting plate. The temperature change measuring optical fiber and the deformation measuring optical fiber are connected with the demodulator through the transmission optical fiber. The measurement interlayer supporting plate is installed between the brake pad and the brake pad back plate so as to carry out braking force measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of braking force measurement, and in particular to a sandwich-type braking force measurement device and method based on Bragg gratings. Background Art

[0002] Braking force measurement involves accurately monitoring and calculating the braking force generated by a vehicle during braking using various sensors or measurement methods. Braking force is typically related to brake pressure, friction coefficient, and the effective contact area of ​​the brake, making it a crucial parameter in vehicle dynamics control systems.

[0003] With the advancement of intelligent connected vehicle technology, accurate braking force measurement plays a key role in ensuring vehicle safety and enhancing active safety control functions. Especially with the prevalence of advanced control systems such as electronic stability control (ESC) and brake-by-wire, single wheel speed measurement is insufficient for accurately sensing wheel-end forces. Accurately measuring braking force enables precise adjustment of the braking system and better energy recovery control, thereby improving vehicle stability and safety.

[0004] However, existing braking force measurement methods mostly rely on estimation, such as inferring pressure through hydraulic systems or piezoelectric sensors. This leads to insufficient measurement accuracy and is unable to fully reflect the pressure changes across the entire effective contact area of ​​the brake pad. In particular, the stability of the sensor in high-temperature environments also has certain limitations, further leading to the problem of insufficient braking force measurement accuracy. Summary of the Invention

[0005] In order to solve the technical problem that most braking force measurement methods in the prior art rely on estimation, such as inferring pressure through hydraulic systems or piezoelectric sensors, which leads to insufficient measurement accuracy and cannot fully reflect the pressure changes of all effective contact areas of the brake pads, especially in high temperature environments, the stability of the sensor also has certain limitations, which further leads to insufficient accuracy of braking force measurement, the present invention provides a sandwich braking force measurement device and method based on Bragg gratings.

[0006] The technical solutions provided by the embodiments of the present invention are as follows:

[0007] First aspect

[0008] The embodiment of the present invention provides a sandwich-type braking force measurement device based on Bragg grating, the system comprising: a measuring sandwich support plate 1, a temperature change measurement unit 2, a plurality of deformation measurement units 3, a transmission optical fiber 4 and a demodulator 5;

[0009] The temperature variation measurement unit 2 includes a temperature variation measurement Bragg grating 201 and a temperature variation measurement optical fiber 202;

[0010] Each of the deformation measurement units 3 includes a deformation component 301, a deformation measurement Bragg grating 302 and a deformation measurement optical fiber 303, and each of the deformation measurement Bragg gratings 302 is connected in series through the deformation measurement optical fiber 303;

[0011] The deformation component 301 is a force-external deformation structure, that is, when the deformation component is subjected to vertical pressure in a first direction, the deformation component 301 generates an outward deformation in a second direction perpendicular to the first direction, and the first direction is perpendicular to the measurement sandwich support plate 1;

[0012] The deformation measurement Bragg gratings 302 are arranged along the second direction, and the deformation components 301 are all fixed in the measurement sandwich support plate 1;

[0013] The temperature change measurement unit 2 and the deformation measurement unit 3 are both arranged in the measurement sandwich support plate 1, and the temperature change measurement optical fiber 202 and the deformation measurement optical fiber 302 are both connected to the demodulator 5 through the transmission optical fiber 4;

[0014] The measuring sandwich support plate 1 is installed between the brake pad and the brake pad back plate to measure the braking force.

[0015] Second aspect

[0016] An embodiment of the present invention provides a sandwich-type braking force measurement method based on a Bragg grating, which is applied to the sandwich-type braking force measurement device based on a Bragg grating as described in the first aspect. The method includes:

[0017] S1: collecting reflected light from the temperature change measurement unit and each deformation measurement unit through the transmission optical fiber;

[0018] S2: parsing the reflected light by the demodulator to obtain a wavelength change of the first reflected light returned by the temperature change measurement Bragg grating and a wavelength change of the second reflected light returned by the deformation measurement Bragg grating;

[0019] S3: Calculating a temperature change according to a change in the wavelength of the first reflected light;

[0020] S4: Calculating the braking pressure of the corresponding deformation measurement unit according to the change in the wavelength of the second reflected light;

[0021] S5: Obtaining the brake pad friction coefficient corresponding to the temperature change by a table lookup method;

[0022] S6: Correcting the brake pressure using the brake pad friction coefficient, and calculating the brake torque, ie, the brake force, based on the corrected brake pressure.

[0023] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0024] In an embodiment of the present invention, a sandwich-type braking force measurement device based on Bragg gratings uses multiple deformation measurement Bragg gratings and temperature change measurement Bragg gratings, which can achieve high-precision measurement of braking pressure and temperature. Unlike traditional technologies that rely on estimation, the present invention can more accurately reflect the pressure changes on the effective contact area of ​​the brake pad by directly measuring the wavelength changes of the Bragg gratings. In addition, through multi-point measurement and temperature compensation functions, the device can fully reflect the distribution of braking pressure and accurately correct the impact of temperature changes on the measurement, ensuring stability and accuracy under different working environments. It can be widely used in braking control systems in modern intelligent connected vehicles. Moreover, the optical fiber transmission signal makes the system have strong anti-electromagnetic interference capabilities, strong adaptability, high reliability, and provide more accurate, stable and efficient braking force measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic structural diagram of a sandwich-type braking force measurement device based on a Bragg grating provided in an embodiment of the present invention;

[0027] Figure 2 A schematic structural diagram of a polygonal columnar force-bearing outward deformation structure provided by an embodiment of the present invention;

[0028] Figure 3 A schematic structural diagram of an elliptical cylinder subjected to outward deformation under load provided by an embodiment of the present invention;

[0029] Figure 4 A schematic structural diagram of a measurement interlayer provided by an embodiment of the present invention;

[0030] Figure 5 A schematic structural diagram of another measurement interlayer provided by an embodiment of the present invention;

[0031] Figure 6 A schematic structural diagram of another measurement interlayer provided by an embodiment of the present invention;

[0032] Figure 7 A schematic diagram of the installation position structure of a sandwich-type braking force measurement device provided by an embodiment of the present invention;

[0033] Figure 8 An exploded structural diagram of the installation position of a sandwich-type braking force measurement device provided by an embodiment of the present invention;

[0034] Figure 9 A schematic structural diagram of a braking force measurement process of a sandwich-type braking force measurement device provided by an embodiment of the present invention;

[0035] Figure 10 A schematic flow chart of a Bragg grating-based method provided in an embodiment of the present invention.

[0036] Reference numerals:

[0037] 1. Measuring interlayer support plate; 2. Temperature change measurement unit; 201. Temperature change measurement Bragg grating; 202. Temperature change measurement optical fiber; 3. Deformation measurement unit; 301. Deformation component; 302. Deformation measurement Bragg grating; 303. Deformation measurement optical fiber; 4. Transmission optical fiber; 401. Optical coupler; 5. Demodulator; 501. Light source; 502. Opto-mechanical module; 503. Wavelength detector; 504. Signal receiver. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0039] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as an "exemplary" in the present invention should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner. Furthermore, in the embodiments of the present invention, "and / or" can mean both or either of the two.

[0040] In the embodiments of the present invention, the terms "image" and "picture" may be used interchangeably. It should be noted that, when the distinction between them is not emphasized, their intended meanings are the same. The terms "of," "corresponding," and "corresponding" may be used interchangeably. It should be noted that, when the distinction between them is not emphasized, their intended meanings are the same.

[0041] In the embodiments of the present invention, sometimes a subscript such as W1 may be mistakenly written as a non-subscript form such as W1. When the difference is not emphasized, the meanings to be expressed are the same.

[0042] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0043] Reference Manual Figure 1 , showing a schematic structural diagram of a sandwich-type braking force measurement device based on Bragg gratings provided in an embodiment of the present invention;

[0044] Reference Manual Figure 4 , showing a schematic structural diagram of a measurement interlayer provided by an embodiment of the present invention;

[0045] Reference Manual Figure 5 , showing a schematic structural diagram of another measurement interlayer provided by an embodiment of the present invention;

[0046] Reference Manual Figure 6 , showing a schematic structural diagram of another measurement interlayer provided by an embodiment of the present invention;

[0047] Reference Manual Figure 7 , showing a schematic diagram of the installation position structure of a sandwich type braking force measurement device provided by an embodiment of the present invention;

[0048] Reference Manual Figure 8 , showing an exploded structural diagram of the installation position of a sandwich-type braking force measurement device provided by an embodiment of the present invention;

[0049] Reference Manual Figure 9 , which shows a structural schematic diagram of the braking force measurement process of a sandwich-type braking force measurement device provided by an embodiment of the present invention.

[0050] Figure 9 Where ω represents the angular velocity of the brake disc, F n Indicates brake pressure, F f represents friction, M Bf This represents the braking torque generated by friction. When a vehicle brakes, the piston, under thrust, moves toward the brake pads, which in turn press against the brake disc, generating braking pressure on the disc. Under braking pressure, the relative motion of the brake pads and the rotating disc creates friction between them, which acts as braking torque on the axle, slowing the vehicle.

[0051] The embodiment of the present invention provides a sandwich-type braking force measurement device based on Bragg gratings, which includes: a measuring sandwich support plate 1, a temperature change measurement unit 2, multiple deformation measurement units 3, a transmission optical fiber 4 and a demodulator 5; the temperature change measurement unit 2 includes a temperature change measurement Bragg grating 201 and a temperature change measurement optical fiber 202; each of the deformation measurement units 3 includes a deformation component 301, a deformation measurement Bragg grating 302 and a deformation measurement optical fiber 303, and each of the deformation measurement Bragg gratings 302 is connected in series through the deformation measurement optical fiber 303; the deformation component 301 is a force-bearing outward deformation structure, that is, when the deformation component is subjected to a first direction, the deformation component 301 is subjected to a force-bearing outward deformation structure, that is, when the deformation component is subjected to a force in a first direction, the deformation component 301 ... Under the condition of vertical pressure, the deformation component 301 generates outward deformation in a second direction perpendicular to the first direction, and the first direction is perpendicular to the measuring interlayer support plate 1; the deformation measurement Bragg grating 302 is arranged along the second direction, and the deformation components 301 are fixed in the measuring interlayer support plate 1; the temperature change measurement unit 2 and the deformation measurement unit 3 are both arranged in the measuring interlayer support plate 1, and the temperature change measurement optical fiber 202 and the deformation measurement optical fiber 302 are connected to the demodulator 5 through the transmission optical fiber 4; the measuring interlayer support plate 1 is installed between the brake pad and the brake pad back plate to measure the braking force.

[0052] The measurement interlayer support plate 1 is the basic support structure for the entire system, installed between the brake pad and the brake pad backing plate. Its primary function is to secure the various components within the device and ensure stable operation of the system during braking. The temperature measurement unit 2, which includes a temperature measurement Bragg grating 201 and a temperature measurement optical fiber 202, is used to measure wavelength changes in the optical signal caused by temperature changes during braking. Temperature changes affect the wavelength of the Bragg grating, so the temperature measurement unit provides temperature compensation to ensure accurate measurements. The deformation measurement unit 3 includes a deformation assembly 301, a deformation measurement Bragg grating 302, and a deformation measurement optical fiber 303. When the deformation assembly is subjected to force, it deforms outward, and the wavelength of the Bragg grating changes with this deformation. The optical fiber transmits these wavelength changes to the demodulator, facilitating accurate measurement of brake pressure. Transmission fiber 4 transmits the signals from the temperature measurement optical fiber 202 and the deformation measurement optical fiber 303 to the demodulator, ensuring stable transmission of the optical signal. The demodulator 5 receives the reflected light signal from the transmission optical fiber 4, analyzes the wavelength change of the light, and then calculates the temperature change and the braking pressure, and finally outputs accurate braking force data.

[0053] Specifically, the braking force measurement process of the sandwich-type braking force measurement device based on Bragg grating includes the following steps: First, the reflected light signals of the temperature change measurement unit 2 and the deformation measurement unit 3 are collected through the transmission optical fiber 4. Next, the demodulator 5 analyzes the wavelength change of the reflected light, obtains the wavelength change of the temperature change measurement Bragg grating, and uses it to calculate the temperature change. Subsequently, the demodulator 5 analyzes the wavelength change of the deformation measurement Bragg grating, and calculates the braking pressure of the corresponding deformation unit based on this. The friction coefficient is obtained by looking up the table according to the temperature change, and it is applied to correct the braking pressure, and finally the accurate braking torque, that is, the braking force, is calculated. The sandwich-type braking force measurement device based on Bragg grating has high precision and high temperature adaptability, and can accurately measure the braking pressure and perform temperature compensation. Through the axial deformation characteristics of the Bragg grating, the device can provide more reliable pressure data than traditional methods, avoiding the problem of sensor stability in high temperature environments.

[0054] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0055] In an embodiment of the present invention, a sandwich-type braking force measurement device based on Bragg gratings uses multiple deformation measurement Bragg gratings and temperature change measurement Bragg gratings, which can achieve high-precision measurement of braking pressure and temperature. Unlike traditional technologies that rely on estimation, the present invention can more accurately reflect the pressure changes on the effective contact area of ​​the brake pad by directly measuring the wavelength changes of the Bragg gratings. In addition, through multi-point measurement and temperature compensation functions, the device can fully reflect the distribution of braking pressure and accurately correct the impact of temperature changes on the measurement, ensuring stability and accuracy under different working environments. It can be widely used in braking control systems in modern intelligent connected vehicles. Moreover, the optical fiber transmission signal makes the system have strong anti-electromagnetic interference capabilities, strong adaptability, high reliability, and provide more accurate, stable and efficient braking force measurement.

[0056] Reference Manual Figure 2 , showing a schematic structural diagram of a polygonal columnar force-bearing outward deformation structure provided by an embodiment of the present invention;

[0057] Reference Manual Figure 3 , showing a schematic structural diagram of an elliptical cylinder subjected to outward deformation according to an embodiment of the present invention;

[0058] In a possible implementation, the force-bearing outward deformation structure includes a polygonal column force-bearing outward deformation structure and an elliptical column force-bearing outward deformation structure; the polygonal column force-bearing outward deformation structure is specifically a hexagonal column force-bearing outward deformation structure.

[0059] Among them, the outward deformation structure of the polygonal column is shown as follows: when an external force, detaF (e.g. Figure 2When a force (indicated by the arrow) acts on a structure, the shape of the structure will change. Figure 2 The figure shows a hexagonal cylinder. When subjected to an external force, the opposite sides of the hexagon expand outward, causing the overall structure to become flatter. The force and deformation directions are perpendicular, meaning that when subjected to the force, the shape deforms outward in a direction perpendicular to the force.

[0060] The outward deformation structure of an elliptical cylinder under load is characterized by the fact that when an external force acts on the structure, the original cylindrical structure undergoes outward deformation and becomes like an ellipse. Figure 3 The figure shows a cylindrical structure that was originally circular. Under the action of an external force, the two sides of the structure become wider, forming an elliptical shape. This outward deformation of the structure occurs in a direction perpendicular to the direction of the force.

[0061] Both polygonal and elliptical cylinders effectively disperse external forces during deformation, resulting in excellent elastic deformation under load. The polygonal cylinder's geometry provides multiple points of force, helping to more evenly distribute applied pressure. The elliptical cylinder, on the other hand, offers greater flexibility and stability, adapting to multi-directional pressure changes and reducing localized stress concentration, thereby improving the system's resistance to deformation.

[0062] In a possible implementation, the deformation measurement optical fiber 303 fixes each of the deformation measurement Bragg gratings 302 in the corresponding deformation component 301 through high-temperature glue.

[0063] As can be understood, the deformation measurement optical fiber 303 secures the deformation measurement Bragg grating 302 to the corresponding deformation assembly 301 via high-temperature adhesive, ensuring that the Bragg grating accurately reflects deformation changes when subjected to external forces. The use of high-temperature adhesive effectively addresses the high temperatures that may occur during braking, maintaining a stable and reliable connection between the optical fiber and the Bragg grating, and ensuring accurate measurement results.

[0064] In a possible implementation, the transmission optical fiber 4 includes a splitter coupler 401 ; the splitter coupler 401 is connected to the temperature change measurement optical fiber 202 and the deformation measurement optical fiber 302 respectively; and the splitter coupler 401 is connected to the demodulator 5 .

[0065] Specifically, transmission fiber 4 is connected to temperature-change measurement fiber 202 and deformation measurement fiber 302 via a splitter coupler 401. The splitter coupler distributes the optical signal from the transmission fiber to different optical fibers, allowing for separate acquisition of temperature change and deformation data. These optical signals are then transmitted to demodulator 5, which uses a wavelength detection module to analyze the changes in the optical signals and ultimately calculate the corresponding temperature change and brake pressure. This configuration effectively enables multi-point temperature and pressure measurement, ensuring both accuracy and reliability.

[0066] In one possible implementation, the demodulator 5 includes: a light source 501, an optomechanical module 502, a wavelength detector 503 and a signal receiver 504; the light source 501 is connected to the optical coupler 401 through the optomechanical module 502; the optomechanical module 502 is connected to the signal receiver 504 through the wavelength detector 503.

[0067] Specifically, the demodulator 5 works together through multiple components to parse the optical signal. First, the light source 501 is connected to the optical coupler 401 through the optomechanical module 502 to provide a light source for measurement. The optomechanical module 502 transmits the optical signal emitted by the light source to the optical coupler, and then the optical coupler transmits the optical signal to the temperature change measurement optical fiber and the deformation measurement optical fiber. After the optical signal is transmitted through these optical fibers, the wavelength detector 503 is responsible for detecting the wavelength change of the reflected light wave. Finally, the signal receiver 504 receives and processes the wavelength change information, and converts it into temperature change and brake pressure through an algorithm, thereby achieving accurate braking force measurement.

[0068] It should be noted that the sandwich-type braking force measurement device based on Bragg gratings can accurately measure the deformation and temperature changes caused by external forces during the braking process through multiple Bragg grating sensors and a temperature compensation mechanism. The device includes a temperature measurement unit 2 and a deformation measurement unit 3, and uses a transmission optical fiber 4 to transmit the signal to a demodulator 5. After reflection, the optical signal is distributed to different optical fibers through a splitter coupler, and then the demodulator 5 analyzes the wavelength changes and calculates the braking pressure and temperature. Through temperature compensation, the friction coefficient is corrected to achieve accurate braking torque calculation. Unlike traditional methods, Bragg gratings can avoid the influence of high temperature on sensors, provide more stable and reliable measurements, and are suitable for the braking control systems of modern smart cars. It can effectively improve the accuracy and anti-interference ability of the system.

[0069] Reference Manual Figure 10 , shows a flow chart of a sandwich-type braking force measurement method based on Bragg grating provided by an embodiment of the present invention.

[0070] The present invention further provides a sandwich-type braking force measurement method based on a Bragg grating, which is applied to the above-mentioned sandwich-type braking force measurement device based on a Bragg grating, and the method comprises:

[0071] In a possible implementation manner, before S1, the method further includes: pre-processing the sandwich-type braking force measurement device; the pre-processing specifically includes:

[0072] The demodulator is turned on, and temperature measurement light is introduced into the temperature change measurement unit, and deformation measurement light of a preset wavelength is introduced into each deformation measurement unit.

[0073] It should be noted that by turning on the demodulator and transmitting temperature measurement light to the temperature measurement unit, and strain measurement light of a preset wavelength to the strain measurement unit, this process initializes the measurement system, ensuring that the optical signal is in the correct state before transmission, thereby obtaining an accurate reflected optical signal. The input of the preset wavelength and temperature measurement light ensures that the response of the optical fiber and Bragg grating meets the predetermined operating conditions, effectively improving the system's measurement accuracy, reducing errors caused by initial signal instability or inconsistency, and enhancing the reliability of the entire measurement process.

[0074] It should be noted that those skilled in the art can set the size of the preset length according to actual needs, and the present invention does not limit this.

[0075] S1: collecting reflected light from the temperature change measurement unit and each deformation measurement unit through the transmission optical fiber;

[0076] It should be noted that the reflected light signals from the temperature and deformation measurement units are collected via optical fiber transmission. During this process, the optical fiber transmits the reflected light from the temperature and deformation measurement Bragg gratings to the demodulator. This design enables simultaneous acquisition of temperature and deformation data, ensuring accurate acquisition of information at multiple points during the braking process. The advantage of this process is that the use of optical fiber for signal transmission avoids electrical interference, ensuring stable and accurate measurement signals. This makes it highly adaptable and reliable, especially in complex operating environments.

[0077] S2: parsing the reflected light by the demodulator to obtain a wavelength change of the first reflected light returned by the temperature change measurement Bragg grating and a wavelength change of the second reflected light returned by the deformation measurement Bragg grating;

[0078] It should be noted that a demodulator analyzes the reflected light to determine the wavelength variations of the temperature- and deformation-measuring Bragg gratings. By detecting wavelength variations in the reflected light signal, the demodulator accurately separates temperature and deformation information. This efficient and accurate analysis of multiple signals, which allows for the acquisition of temperature and brake pressure data, avoids the errors associated with traditional estimation methods and ensures precise measurement of the brake system in diverse operating environments.

[0079] S3: Calculating a temperature change according to a change in the wavelength of the first reflected light;

[0080] In a possible implementation, the temperature change is calculated as follows:

[0081]

[0082] Among them, λ B1 Indicates the wavelength of the temperature measurement light, Δλ B1 Indicates the change in wavelength of the reflected light of the temperature measurement light, ΔT indicates the temperature change, β T Indicates the thermal sensitivity of the Bragg grating measured by temperature change.

[0083] It should be noted that by calculating this temperature change, wavelength changes can be directly correlated with temperature changes, allowing for precise temperature calculation. By sensitively reflecting temperature changes through changes in light wavelength, high-precision temperature measurement is ensured, providing a reliable basis for precise control of braking systems in high-temperature environments.

[0084] S4: Calculating the braking pressure of the corresponding deformation measurement unit according to the change in the wavelength of the second reflected light;

[0085] In a possible implementation manner, the calculation formula for the brake pressure is specifically:

[0086]

[0087] Among them, λ B2 Denotes the wavelength of the deformation measurement light, Δλ B2 Indicates the change in wavelength of the reflected light of the deformation measurement light, β ε Denotes the strain sensitivity of the Bragg grating for deformation measurement, ΔF n represents the braking pressure applied to a single deformation measurement unit, k represents the system adjustment coefficient, S represents the cross-sectional area of ​​the deformation measurement Bragg grating, and E represents the Young's modulus of the deformation measurement Bragg grating.

[0088] Among them, the system adjustment coefficient can be calculated through calibration measurement. This coefficient value is a function value with Poisson parameter and angle as independent variables. The coefficient value is the amplification or reduction coefficient of the deformation measurement unit for pressure. The specific function can be determined according to the specific processed structure, and different deformation measurement units can have different system adjustment coefficients. That is, the specific system adjustment coefficient can be obtained through calibration measurement based on the actual structure. Among them, the size of the angle is obtained according to the specific structure of the outward deformation structure under force, such as Figure 2 and Figure 3 As shown, the angle α specifically represents the angle between the deformation measurement Bragg grating and the adjacent side of the deformation measurement Bragg grating in the outward-deformed structure under force.

[0089] It's important to note that the brake pressure calculation takes into account the geometric parameters of the strain gauge and the effects of temperature, accurately converting changes in light wavelength into brake pressure. This approach simultaneously accounts for strain, temperature, and material properties, ensuring accurate brake pressure data under various operating conditions, providing greater accuracy and reliability.

[0090] S5: Obtaining the brake pad friction coefficient corresponding to the temperature change by a table lookup method;

[0091] Specifically, the table lookup method uses a pre-established table of temperature-friction coefficient relationships, inputs the currently measured temperature change, and finds the corresponding friction coefficient value. This table, typically derived from experimental data, covers the friction characteristics of brake pads at different temperatures.

[0092] S6: Correcting the brake pressure using the brake pad friction coefficient, and calculating the brake torque, ie, the brake force, based on the corrected brake pressure.

[0093] In a possible implementation manner, the braking force is calculated as follows:

[0094]

[0095] T Bf =F n ·f·R

[0096] Among them, T Bf Indicates braking force, F n Indicates the braking pressure applied to the sandwich-type braking force measuring device, ΔF ni represents the braking pressure on the i-th deformation measurement unit, ΔS represents the effective area of ​​the brake pad, R represents the distance between the brake pad and the axle, and f represents the friction coefficient of the brake pad.

[0097] The effective area of ​​the brake pad represents the effective area of ​​the brake pad friction layer represented by each pressure measurement grating, i.e., the deformation measurement Bragg grating, which is equivalent to the idea of ​​infinitesimal elements. The size of this area can be defined according to actual needs.

[0098] It should be noted that this process ensures accurate correction of the brake pressure and friction coefficient measured at multiple points, avoids error accumulation, improves the accuracy of the brake torque and the reliability of the system, and maintains stability, especially under high temperatures or complex working conditions.

[0099] In actual application, optical fibers first collect the reflected light signals from the temperature measurement unit and the deformation measurement unit. Transmission via optical fibers avoids electrical interference and ensures signal stability and accuracy. Next, a demodulator analyzes the reflected light signals to extract temperature and deformation information. The temperature change is calculated by calculating the wavelength change of the reflected light. Braking pressure is then calculated based on the wavelength change of the deformation measurement Bragg grating. A table lookup method is then used to determine the friction coefficient corresponding to the temperature change, further ensuring consistency between friction characteristics and actual temperature. Finally, the corrected brake pressure is used to calculate the accurate braking torque, thereby obtaining the braking force. This entire process exhibits high precision, high-temperature adaptability, and interference resistance, enabling stable operation in complex environments and ensuring precise control of the braking system.

[0100] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0101] In an embodiment of the present invention, a sandwich-type braking force measurement device based on Bragg gratings uses multiple deformation measurement Bragg gratings and temperature change measurement Bragg gratings, which can achieve high-precision measurement of braking pressure and temperature. Unlike traditional technologies that rely on estimation, the present invention can more accurately reflect the pressure changes on the effective contact area of ​​the brake pad by directly measuring the wavelength changes of the Bragg gratings. In addition, through multi-point measurement and temperature compensation functions, the device can fully reflect the distribution of braking pressure and accurately correct the impact of temperature changes on the measurement, ensuring stability and accuracy under different working environments. It can be widely used in braking control systems in modern intelligent connected vehicles. Moreover, the optical fiber transmission signal makes the system have strong anti-electromagnetic interference capabilities, strong adaptability, high reliability, and provide more accurate, stable and efficient braking force measurement.

[0102] The above embodiments can be implemented in whole or in part through software, hardware (such as circuits), firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, the processes or functions described in accordance with the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired method (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage system such as a server or data center that contains a collection of one or more available media. The available medium can be a magnetic medium (such as a floppy disk, hard disk, or tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state drive.

[0103] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. A and B can be singular or plural. Furthermore, the character " / " as used herein generally indicates an "or" relationship between the associated objects, but it may also indicate an "and / or" relationship. For specific understanding, please refer to the context.

[0104] In this disclosure, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or plural.

[0105] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0106] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0107] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0108] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0109] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0110] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0111] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer system (which can be a personal computer, a server, or a network system, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0112] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

[0113] There are a few points to note:

[0114] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0115] (2) For the sake of clarity, the thickness of layers or regions in the drawings used to describe the embodiments of the present invention are exaggerated or reduced, that is, these drawings are not drawn to scale. It is understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or intervening elements may be present.

[0116] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to form new embodiments.

[0117] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A sandwich-type braking force measurement device based on Bragg grating, characterized in that: include: Measuring sandwich support plate, temperature change measurement unit, multiple deformation measurement units, transmission optical fiber and demodulator; The temperature variation measurement unit includes a temperature variation measurement Bragg grating and a temperature variation measurement optical fiber; Each of the deformation measurement units includes a deformation component, a deformation measurement Bragg grating and a deformation measurement optical fiber, and each of the deformation measurement Bragg gratings is connected in series through the deformation measurement optical fiber; The deformable component is a force-bearing outward-deformable structure, that is, when the deformable component is subjected to vertical pressure in a first direction, the deformable component generates an outward deformation in a second direction perpendicular to the first direction, and the first direction is perpendicular to the measurement sandwich support plate; The deformation measurement Bragg gratings are arranged along the second direction, and the deformation components are all fixed in the measurement sandwich support plate; The temperature change measurement unit and the deformation measurement unit are both arranged in the measurement sandwich support plate, and the temperature change measurement optical fiber and the deformation measurement optical fiber are both connected to the demodulator through the transmission optical fiber; The measuring sandwich support plate is installed between the brake pad and the brake pad back plate to measure the braking force.

2. The sandwich-type braking force measurement device based on Bragg grating according to claim 1, characterized in that: The force-bearing outward deformation structure includes a polygonal column force-bearing outward deformation structure and an elliptical column force-bearing outward deformation structure; the polygonal column force-bearing outward deformation structure is specifically a hexagonal column force-bearing outward deformation structure.

3. The sandwich-type braking force measurement device based on Bragg grating according to claim 1, characterized in that: The deformation measurement optical fiber fixes each of the deformation measurement Bragg gratings in the corresponding deformation component through high-temperature glue.

4. The sandwich-type braking force measurement device based on Bragg grating according to claim 1, characterized in that: The transmission optical fiber includes a splitter coupler; the splitter coupler is connected to the temperature change measurement optical fiber and the deformation measurement optical fiber respectively; the splitter coupler is connected to the demodulator.

5. The sandwich-type braking force measurement device based on Bragg grating according to claim 4, characterized in that: The demodulator includes: a light source, an optomechanical module, a wavelength detector and a signal receiver; the light source is connected to the optical coupler via the optomechanical module; the optomechanical module is connected to the signal receiver via the wavelength detector.

6. A sandwich-type braking force measurement method based on Bragg grating, characterized in that: The method for the sandwich-type braking force measurement device based on Bragg gratings according to any one of claims 1 to 5 includes: S1: collecting reflected light from the temperature change measurement unit and each deformation measurement unit through the transmission optical fiber; S2: parsing the reflected light by the demodulator to obtain a wavelength change of the first reflected light returned by the temperature change measurement Bragg grating and a wavelength change of the second reflected light returned by the deformation measurement Bragg grating; S3: Calculating a temperature change according to a change in the wavelength of the first reflected light; S4: Calculating the braking pressure of the corresponding deformation measurement unit according to the change in the wavelength of the second reflected light; S5: Obtaining the brake pad friction coefficient corresponding to the temperature change by a table lookup method; S6: Correcting the brake pressure using the brake pad friction coefficient, and calculating the brake torque, ie, the brake force, based on the corrected brake pressure.

7. The sandwich-type braking force measurement method based on Bragg grating according to claim 6, characterized in that: Before S1, the method further includes: pre-processing the sandwich-type braking force measurement device; the pre-processing specifically includes: The demodulator is turned on, and temperature measurement light is introduced into the temperature change measurement unit, and deformation measurement light of a preset wavelength is introduced into each deformation measurement unit.

8. The sandwich-type braking force measurement method based on Bragg grating according to claim 6, characterized in that: The temperature change is calculated as follows: Among them, λ B1 Indicates the wavelength of the temperature measurement light, Δλ B1 Indicates the change in wavelength of the reflected light of the temperature measurement light, ΔT indicates the temperature change, β T Indicates the thermal sensitivity of the Bragg grating measured by temperature change.

9. The sandwich-type braking force measurement method based on Bragg grating according to claim 6, characterized in that: The calculation formula of the brake pressure is specifically: Among them, λ B2 Denotes the wavelength of the deformation measurement light, Δλ B2 Indicates the change in wavelength of the reflected light of the deformation measurement light, β ε Denotes the strain sensitivity of the deformation measurement Bragg grating, ΔF n represents the braking pressure applied to a single deformation measurement unit, k represents the system adjustment coefficient, S represents the cross-sectional area of ​​the deformation measurement Bragg grating, and E represents the Young's modulus of the deformation measurement Bragg grating.

10. The sandwich-type braking force measurement method based on Bragg grating according to claim 6, characterized in that: The braking force is calculated as follows: T Bf =F n ·f·R Among them, T Bf Indicates braking force, F n Indicates the braking pressure applied to the sandwich-type braking force measuring device, ΔF ni represents the braking pressure on the i-th deformation measurement unit, ΔS represents the effective area of ​​the brake pad, R represents the distance between the brake pad and the axle, and f represents the friction coefficient of the brake pad.

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