Method and system for determining the braking torque by means of detection performed by a photonic sensor at a fixed joint between a brake caliper body and a corresponding support

Abstract

A method and system for determining a braking torque by detection performed by a photon sensor at a fixed joint between a brake caliper body and a corresponding support is provided. The method comprises the following steps: inserting a washer device at the fixed joint so that the washer device is fixed and compressed between the caliper body and the caliper support, wherein the washer device is combined with a deformation and / or strain sensor at a corresponding detection position, the sensor being arranged to detect the deformation and / or strain and being an optical fiber strain sensor; detecting a local deformation and / or strain acting on the corresponding detection position by means of the optical fiber strain sensor and generating a corresponding photon signal representing the detected deformation and / or strain; receiving a first photon signal by an optical reading / interrogation unit optically connected to the optical fiber strain sensor; generating an electrical signal representing the detected local deformation and / or strain based on the received first photon signal; and determining the braking torque based on the above electrical signal.

Description

Technical Field

[0001] The present invention relates to a method and a system for determining the braking torque by detection with a photonic sensor, ie a fiber optic sensor, at a fixed joint between a brake caliper body and a corresponding support.

[0002] The invention also relates to a brake caliper with sensors equipped to allow the implementation of the above method. Background Art

[0003] In order to control, monitor and actuate a braking system, for example an electronically controlled disc brake system, it is very useful to know in real time and as accurately as possible the value of the force or braking torque applied by the brake calipers of the braking system during a braking action.

[0004] However, it is difficult to directly, accurately and reliably measure the braking force and / or torque applied by the brake caliper of a braking system.

[0005] In this respect, there is a tendency in the known art to determine the braking torque and / or braking force based on indirect measurements, which are quantities closely related to the braking torque and / or force, for example the force acting at different points of the brake caliper.

[0006] On the other hand, the additional requirement must be taken into account, namely the need to use sensor devices that are as small and compact as possible, so that they can be easily integrated into the brake system without causing functional problems.

[0007] In this context, some compact sensor devices are known which are able to detect and / or measure the transverse (shear) forces acting between the brake caliper support and the vehicle wheel hub using strain sensors.

[0008] However, such known devices can determine the braking force and / or the torque based on the transverse force measurements performed, but with poor accuracy and with a relatively limited range of measurable forces.

[0009] Furthermore, the results provided by such a device are not completely independent of the tightening torque of the screws used to fix the two components between which the force is measured. In other words, the results are independent of axial forces which interfere with the accuracy of the estimation of the braking force and / or torque.

[0010] In view of the above, there is a strong need for devices and methods to more accurately determine the braking torque and / or force by indirect measurements performed at the interface between the brake caliper body and the brake caliper support or between the brake caliper support and the wheel hub.

[0011] For this application, additional requirements of the measuring device are compactness, robustness, ease of installation (eg using already available fixing systems for fixed brake calipers) and versatility for use in the context of fixed or floating caliper disc brakes.

[0012] As mentioned above, the solutions currently available from the prior art cannot fully meet the above requirements. Summary of the invention

[0013] The object of the present invention is to provide a method for determining the braking torque by detection performed by a photonic sensor at the fixed joint between a brake caliper body and a corresponding support, which method allows to at least partially solve the drawbacks described above with reference to the prior art and respond to the above-mentioned need particularly felt in the considered technical field.

[0014] This object and other objects are achieved by a method for detecting braking torque according to an embodiment of the present invention.

[0015] Some preferred embodiments of this method are described below.

[0016] Another object of the invention is to provide a corresponding system for determining the braking torque through detection performed by a photonic sensor at the fixed joint between the brake caliper body and the corresponding support.

[0017] This object is achieved by a process according to an embodiment of the present invention.

[0018] Some preferred embodiments of such a system are described below.

[0019] Another object of the present invention is to provide a gasket device for deformation and / or strain detection included in the above system and which can be used in the above method.

[0020] These and other objects are achieved by an apparatus according to an embodiment of the present invention.

[0021] Some preferred embodiments of such a device are described below.

[0022] Another object of the present invention is to provide a brake caliper with sensor for a vehicle braking system equipped to allow the above method to be performed.

[0023] These and other objects are achieved by a brake caliper with a sensor according to an embodiment of the present invention.

[0024] Some preferred embodiments of such a caliper are described below.

[0025] Another object of the invention is to provide a braking system using at least one brake caliper with a sensor as described above or using the system as described above for determining the braking torque.

[0026] These and other objects are achieved by a brake system according to an embodiment of the present invention.

[0027] Finally, it is an object of the present invention to provide a method for manufacturing a gasket arrangement according to an embodiment of the present invention.

[0028] These and other objects are achieved by a manufacturing method according to an embodiment of the present invention.

[0029] Some preferred embodiments of this manufacturing method are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other characteristics and advantages of the method and system according to the invention will be apparent from the following description of a preferred embodiment thereof, given by way of non-limiting example and with reference to the accompanying drawings, in which:

[0031] - Figure 1 , Figure 2A , Figure 2B , Figure 3A , Figure 3B Various embodiments of a brake caliper with a sensor for detecting braking force according to the present invention are shown by means of a functional block diagram;

[0032] - Figure 4 , Figure 5 , Figure 6 , Fig. 7A and Figure 7B shows a perspective view, a side view, and an orthogonal view of a gasket device including a strain sensor according to some embodiments included in the present invention;

[0033] - Fig. 8A , Figure 8B , Figure 8C shows cross-sectional views of three embodiments of a gasket device including a strain sensor included in the present invention;

[0034] - Fig. 9 and Fig.10 A perspective view and an exploded perspective view showing another embodiment of a brake caliper with a sensor according to the present invention;

[0035] - Fig.11 Some details of the fixed joint between the brake caliper body and the brake caliper support according to an embodiment of the present invention are shown, wherein a washer arrangement is installed, such as Figures 4 to 6 , Fig. 7A , Figure 7B , Fig. 8A , Figure 8B , Figure 8C Gasket device in;

[0036] - Figure 12 to Figure 14 is a functional block diagram of various embodiments of an optical reading / interrogation unit included in the above-described system for determining brake torque. DETAILED DESCRIPTION

[0037] refer to Figures 1 to 14 , describes a method for determining the braking torque BT generated by the actuation of a vehicle braking system by means of detection performed at at least one fixed joint (i, ii, iii, iv) between a brake caliper body 60 and a corresponding support 61 (or, in another possible application, between an axle and a suspension of a wheel).

[0038] The method first comprises the following steps: inserting at least one washer device D at at least one of the above-mentioned fixed joints (i, ii, iii, iv) so that: the washer device D is fixed and pressed between the brake caliper body 60 and the brake caliper support 61, or between the brake caliper support 61 and the head of the clamping element 63, 64, or between the axle and the wheel suspension.

[0039] The washer device D is susceptible to deformation when exposed to forces, such that the deformation and / or force S locally present at each point of the washer device D represents a force acting at the at least one fixed joint dependent on the braking torque BT.

[0040] The aforementioned gasket device D is combined with at least one deformation and / or strain sensor (FBG) at the corresponding detection position, and the at least one deformation and / or strain sensor (FBG) is arranged to detect the deformation and / or strain of the three space vector components representing the force acting on the gasket device D at the detection position.

[0041] The at least one deformation and / or strain sensor (FBG) is a fiber optic strain sensor FBG of the fiber Bragg grating type.

[0042] Then, the method comprises the following steps: detecting a local deformation and / or strain S acting on a corresponding detection position by means of each of the at least one optical fiber strain sensors FBG, and generating a corresponding at least one photon signal L representing the detected deformation and / or strain S.

[0043] Therefore, the method provides receiving the aforementioned at least one photon signal L by an optical reading / interrogation unit 4, which is optically connected to the aforementioned at least one optical fiber strain sensor 2, and based on the received aforementioned at least one photon signal L, the optical reading / interrogation unit 4 generates at least one first electrical signal E representing the detected local deformation and / or strain S.

[0044] Finally, the method comprises a step of determining a braking torque BT based on the aforementioned at least one electrical signal E representative of the deformation and / or strain S.

[0045] According to an embodiment of the method, the inserting step includes: inserting a plurality of gasket devices D1, D2, D3, D4, each gasket device being located at a corresponding fixed joint (i, ii, iii, iv), and each of these gasket devices being combined with a plurality of deformation and / or strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6).

[0046] In this case, the determining step comprises determining the braking torque BT based on a plurality of electrical signals Ejk, each of which is derived from a respective photon signal Ljk representing a respective deformation and / or strain Sij detected by a respective optical fiber strain sensor. In the above notation, j is an index indicating one of the plurality of washer devices, and k is an index indicating one of the plurality of optical fiber strain sensors included in the washer device.

[0047] In various embodiments, any number of gasket arrangements D may be used.

[0048] In various embodiments, each gasket device D may include any number of optical fiber strain sensors FBG.

[0049] According to a preferred embodiment of the method, the determining step includes: inserting a first washer device D1 at the first fixed joint (i) between the head of the first fixing bolt 63 and the first part of the caliper support 61; inserting a second washer device D2 at the first fixed joint (ii) between the head of the second fixing bolt 64 and the second part of the caliper support 61; inserting a third washer device D3 at the third fixed joint (iii) between the third part of the caliper support 61 and the caliper body 60; inserting a fourth washer device D4 at the fourth fixed joint (iv) between the fourth part of the caliper support 61 and the caliper body 60.

[0050] According to different embodiments, the method may provide any combination of one, two, three or four of the aforementioned gasket devices, each gasket device being performed in the above-mentioned corresponding manner.

[0051] According to an embodiment of the method, one or more optical fiber strain sensors FBG are included in an optical fiber 14 arranged in a tangential peripheral band 13 of the gasket device D. Furthermore, each of the aforementioned optical fiber strain sensors FBG is obtained in a corresponding optical fiber portion tilted with respect to a radial plane (p) of the gasket at an acute or obtuse tilt angle different from each of the values ​​0°, 90°, 180° and 270°, so as to detect a strain S in a direction different from the normal direction and the tangential direction relative to the gasket, so that the detected strain S depends on both the normal component and the tangential component of the force acting on the sensor.

[0052] According to a preferred embodiment, the method comprises the following further steps: incorporating at least one corresponding optical fiber temperature sensor 5 of the fiber Bragg grating type in the at least one gasket device D; then, detecting the temperature value T present at the corresponding position by means of the at least one temperature sensor 5, and generating at least one corresponding auxiliary photon signal Lt representing the measured temperature value T; then, receiving the generated at least one auxiliary photon signal Lt by an optical reading / implementation unit 4 optically connected to the at least one temperature sensor 5; and generating at least one auxiliary electrical signal Et representing the temperature by the optical reading / implementation unit 4 based on the received at least one auxiliary photon signal Lt;

[0053] In this case, the determination step comprises processing the above-mentioned at least one first electrical signal E and the above-mentioned at least one electrical signal Et so as to obtain a measured value of the braking torque BT taking into account temperature compensation.

[0054] The above-mentioned Fiber Bragg Grating optical sensor (hereinafter also referred to as "FBG sensor") is a deformation and / or strain sensor of a type known per se.

[0055] As is well known, FBG sensors are very sensitive and versatile optical devices for measuring a variety of physical parameters including strain and temperature. In their simplest form, FBG sensors are obtained by spatially periodically modulating the refractive index inscribed in the core of an optical fiber (e.g., by photosensitization phenomena or using femtosecond light pulses).

[0056] FBG sensors exploit the existence of a resonant condition that reflects the so-called "Bragg wavelength" λ B The incident light at B is limited to λ B =2n eff Λ, where n eff is the effective refractive index of the fundamental mode of the fiber, and Λ is the spatial spacing (period) of the grating.

[0057] The operating principle of FBG sensors is based on the following property: any change in the effective refractive index or grating spacing caused by external effects (such as strain or temperature) will lead to a corresponding shift Δλ of the operating wavelength (Bragg wavelength). B , the drift can be obtained from formula [1]:

[0058]

[0059] where Δλ B =λ-λ B is the Bragg wavelength relative to the reference Bragg wavelength λ B , k is the scaling factor, and α T is the thermo-optical coefficient; for silicon optical fiber in the 1550nm range, the Bragg wavelength drift is linearly related to the longitudinal strain ε, the sensitivity value is about 1.2pm / με, and the sensitivity value of temperature change is about 11pm / ℃.

[0060] According to an embodiment, the aforementioned at least one temperature sensor 5 comprises a Fiber Bragg Grating manufactured in the same optical fiber 14 as that in which at least one deformation and / or strain sensor FBG is manufactured.

[0061] FBG sensors are "passive" sensors, meaning that they do not need to be powered, but are enabled by illumination, i.e. by sending optical enabling irradiation at an appropriate wavelength (e.g., the Bragg wavelength) in the optical fiber section containing the grating in the sensor. In response, the FBG sensor reflects or transmits an optical (i.e., photonic) signal that depends not only on the incident irradiation, but also on the strain conditions to which the grating itself is subjected. In different embodiments of the method to be presented below, this photonic signal may be a transmitted optical signal (or optical spectrum) or a reflected optical signal (or optical spectrum).

[0062] According to an embodiment of the method (in Figure 1 ), the optical fiber strain sensor FBG is connected to the optical reading / interrogation unit 4 by means of a first connecting optical fiber 31. In addition, the optical reading / interrogation unit 4 is configured to enable the aforementioned optical fiber strain sensor FBG by sending optical activation radiation OA via the aforementioned first connecting optical fiber 31. In addition, the aforementioned photon signal L includes a first optical spectrum L reflected by the strain sensor FBG of the fiber Bragg grating type, and the first optical spectrum L reaches the optical reading / interrogation unit 4 through the first connecting optical fiber 31.

[0063] According to another embodiment of the method ( Figure 2A), the optical fiber strain sensor FBG is connected to the optical reading / interrogation unit 4 by means of a first input connection optical fiber 32 and a second output connection optical fiber 33. In addition, the optical reading / interrogation unit 4 is configured to enable the above-mentioned optical fiber strain sensor 2 by sending an optical enabling irradiation OA via the first input connection optical fiber 32. In addition, the above-mentioned photon signal L includes an optical spectrum L sent by the fiber Bragg grating type strain sensor FBG, and the optical spectrum L reaches the optical reading / interrogation unit 4 through the second connection optical fiber 33.

[0064] According to an embodiment, each connection between each optical fiber obtaining a Fiber Bragg Grating type sensor and a corresponding connecting optical fiber connected to an optical reading / interrogation unit is made by means of a fiber optic splice or a detachable photonic connecting element (optical connector).

[0065] According to an embodiment of the method, a plurality of optical fiber strain sensors FBG are provided and advantageously used.

[0066] In such an implementation ( Figure 2A and Figure 2B ), each of the optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) of the device is made in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6) by means of a corresponding Bragg grating.

[0067] In this case, the step of generating at least one corresponding photon signal includes: generating multiple corresponding photon signals (L1, L2, L3, L4, L5, L6); the receiving step includes: receiving the aforementioned multiple photon signals (L1, L2, L3, L4, L5, L6) by an optical reading / interrogation unit (4); the step of generating at least one first electrical signal E includes: generating corresponding multiple electrical signals (E1, E2, E3, E4, E5, E6) based on the received multiple photon signals (L1, L2, L3, L4, L5, L6); the processing step includes: processing the multiple electrical signals (E1, E2, E3, E4, E5, E6) to obtain the measured value of the braking torque BT.

[0068] According to an embodiment, the method comprises the following further steps: sending respective light-enabling irradiations (OA1, OA2, OA3, OA4, OA5, OA6) at different respective operating wavelengths (λ1, λ2, λ3, λ4, λ5, λ6) by means of wavelength division multiplexing (WDM) transmission technology via a connecting optical fiber 3 to a plurality of deformation and / or strain sensors by means of an optical reading / interrogation element 4; the method then provides: receiving a respective optical spectrum (e.g., FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) of each of the plurality of deformation and / or strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) via the connecting optical fiber (3); Figure 2A ) or the corresponding optical spectrum reflected by each sensor (as shown Figure 2B As shown) and the corresponding optical spectra are distinguished by demultiplexing using wavelength division multiplexing (WDM) technology, wherein each of the reflected optical spectra corresponds to a corresponding photon signal (L1, L2, L3, L4, L5, L6).

[0069] According to an embodiment, each connection between each optical fiber obtaining a Fiber Bragg Grating type sensor and a corresponding connecting optical fiber connected to an optical reading / interrogation unit is made by means of a fiber optic splice or a detachable photonic connecting element (optical connector).

[0070] According to an embodiment, the method comprises the following steps: before the determination step, sending the above-mentioned at least one electrical signal E and / or the auxiliary electrical signal Et to the control unit 20 .

[0071] In this case, the determination step includes: calculating the braking torque BT by the processor of the control unit 20 based on the aforementioned at least one electrical signal E, or based on the aforementioned at least one first electrical signal E and the auxiliary electrical signal Et, or based on the aforementioned multiple electrical signals among the multiple electrical signals (Ea, E1, E2, E3, E4, E5, E6; Eij) and multiple auxiliary electrical signals among the at least one auxiliary electrical signal Et with the aid of one or more algorithms executed by one or more software programs.

[0072] According to an embodiment of the method, the calculation step comprises calculating the braking torque BT by means of a predetermined nonlinear relationship between the braking torque and a deformation and / or strain detected by at least one deformation and / or strain sensor FBG incorporated in the washer device D at a corresponding location.

[0073] This predetermined non-linear relationship is represented by a computer model or look-up table stored so as to be accessible by the processor of the control unit 20 .

[0074] The aforementioned predetermined non-linear relationship is determined by means of testing and / or characterization and / or calibration performed after at least one washer device D containing at least one deformation and / or strain sensor D has been positioned and fixed at a corresponding fixed joint between the brake caliper body and the brake caliper support.

[0075] According to an embodiment of the method (e.g. Figure 3A As shown in the figure, the calculation step includes: for each of the four washer devices D1, D2, D3, D4, the corresponding nonlinear model NM1, NM2, NM3, NM4 is suitable for determining the three vector components of the corresponding vector force acting on the washer device, and the three vector components include three-axis forces F1, F2, F3, F4; then, the braking torque BT is calculated based on the three-axis forces F1, F2, F3, F4 determined by the four nonlinear models.

[0076] According to another embodiment of the method (e.g. Figure 3B ), the calculation steps include: for two gasket devices D1, D2 (or similarly, for Fig. 9 and Fig.10 Each washer in the washers D1, D2, D3, D4 shown in the figure (or any other combination of two washers among them) defines a corresponding nonlinear model NM1, NM2, which is suitable for determining three vector components of the corresponding vector force acting on the washer device, and the three vector components include three-axis forces F1, F2; then, the braking torque BT is calculated based on the three-axis forces F1, F2 determined by the four nonlinear models.

[0077] According to the implementation scheme, the step of defining a nonlinear model for the gasket device includes: defining a basic nonlinear model with the help of functional and / or structural simulations, such as calculations based on the finite element method (FEM); and then refining the parameters of the nonlinear model with the help of an initial calibration phase based on the strain measurement values ​​Sij detected by the corresponding optical fiber strain sensors of the gasket device and the synchronous measurement values ​​of the physical quantities that generate the strain Sij under known experimental conditions, wherein the aforementioned physical quantities include, for example, the braking torque BT; the preload caused by the tension V of the fixing screws during assembly and / or the pressure P applied by the brake caliper.

[0078] For example, a FEM simulation can provide a nonlinear model containing adjustable parameters of the relationship between the measured strains at one or more points of the joint between the body and the caliper support. Then, a calibration operation is performed in the laboratory based on experimental measurements under known conditions of screw tension preload and brake caliper pressure. In an initial step of this calibration, in the laboratory, the strains present at one or more points of the joint between the body and the caliper support (with the help of corresponding gasket devices) and at one or more points of each gasket device, as well as the braking torque generating such strains, can be measured. The aforementioned measurements allow the parameters of the basic nonlinear model to be adjusted, effectively allowing the characterization of the nonlinear ratio between the detected strain and the braking torque generating this strain.

[0079] The aforementioned calculations and processing allow defining a non-linear relationship between the strain measurements at one or more points of the junction between the caliper body and the support and the braking torque, thus allowing the braking torque to be estimated based on the strain measurements performed.

[0080] According to an embodiment of the method, the processing step comprises acquiring in real time dynamic measurements of the trend of the braking force and / or torque BT based on the temporal evolution of the detected deformation and / or strain.

[0081] Now refer to Figures 4 to 6 , Fig. 7A , Figure 7B , Fig. 8A , Figure 8B , Figure 8C A deformation and / or strain sensing washer device D is described.

[0082] Such a gasket device D comprises a device body 1 and an optical fiber 14 containing one or more Fiber Bragg Grating FBG type strain sensors.

[0083] The shape of the device body 1 is designed to be a washer or a roughly disc-shaped plate extending mainly along the radial reference plane p, and the device body 1 has a first flat surface 11 and a second flat surface 12 parallel to the radial reference plane p. The device body 1 is suitable for being arranged to be in close contact with the surface of the fixing device and / or the brake caliper support 61 and / or the brake caliper body 60, so that the device body 1 can be installed at the fixed joints (i, ii, iii, iv) between the brake caliper body 60 and the brake caliper support 61, or between the brake caliper support 61 and the heads of the clamping elements 63, 64, or between the axle and the wheel suspension.

[0084] The gasket body 1 has a tangential peripheral band (and / or recess) 13 extending along a portion or periphery of the body 1 of the gasket device D.

[0085] The gasket body 1 is susceptible to deformation when subjected to a force, so that the deformation and / or force S locally present in each point of the gasket device D represents the force acting on the gasket device D.

[0086] The optical fibers 14 are arranged along or at the tangential peripheral bands 13 .

[0087] The optical fiber 14 includes one or more deformation and / or strain fiber Bragg grating type optical fiber strain sensors (FBG), each of which is configured to determine the local deformation and / or strain S acting at a corresponding detection position and generate at least one corresponding photon signal L representing the detected deformation and / or strain S.

[0088] Each of the aforementioned optical fiber strain sensors FBG is obtained in a corresponding optical fiber portion tilted relative to a radial plane p at an acute tilt angle or an obtuse tilt angle different from each of the values ​​0°, 90°, 180° and 270°, so as to detect strain S in a direction different from the normal direction, the tangential direction, and the tangential or radial direction relative to the reference plane p of the gasket, so that the detected strain S depends on both the normal component and the tangential component of the force acting on the sensor and / or on each of the three spatial vector components of the force acting on the sensor.

[0089] The optical fiber containing the optical fiber strain sensor fiber FBG is adapted to transmit the aforementioned at least one photon signal L generated by the at least one optical fiber strain sensor FBG and to receive at least one enabling radiation OA for the respective at least one optical fiber strain sensor FBG.

[0090] According to an implementation example, the optical fiber 14 is connected to a protective output tube 35 , allowing the device to be connected to the optical reading / interrogation unit 4 .

[0091] According to an embodiment, the above-mentioned inclination angle is in the range of ±30° to ±45°.

[0092] According to a preferred embodiment (e.g. Figure 6 The above-mentioned tilt angle is ±30°.

[0093] Depending on the embodiment of the device (e.g. Figure 4 ), the aforementioned optical fiber includes a plurality of optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) arranged along the peripheral extension of the optical fiber 14 and / or equidistantly spaced apart.

[0094] Each of the optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) incorporated in the device D is made with the aid of a corresponding Bragg grating in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6), and each of the optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) incorporated in the device D is suitable for: being excited with the aid of corresponding light irradiation at a corresponding wavelength (light irradiation belonging to the total excitation in wavelength division multiplexing WDM); and, generating a transmitted or reflected optical spectrum constituting a corresponding photon signal (L1, L2, L3, L4, L5, L6).

[0095] According to a preferred embodiment, the plurality of optical fiber strain sensors FBG include six optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6).

[0096] According to an implementation example, the central operating wavelengths of the six optical fiber strain sensors are 1535 nm, 1540 nm, 1545 nm, 1550 nm, 1555 nm, and 1560 nm.

[0097] According to an implementation example, each optical fiber strain sensor FBG has a grating of 1 mm in length and a reflectivity of 50% or more; six optical fiber strain sensors are evenly spaced apart at a distance of 14 mm from each other.

[0098] According to the embodiment, the optical fiber 14 further includes an optical fiber temperature sensor 5 .

[0099] According to a possible embodiment, the geometry of the body of the washer device D and the material from which it is made are selected in accordance with the requirements of ensuring mechanical strength to the axial fixed preload and to the shear forces generated by the braking action and of optimizing the deformation of the body of the washer device D without reaching critical structural strains.

[0100] In particular, according to a preferred embodiment, the body of the washer device D is made of steel, or titanium or aluminum.

[0101] According to different embodiments, the gasket device D may include multiple parts connected together and / or multiple parts that can be detached and reattached to each other. In particular, the body 1 of the gasket device D may include various parts connected together and / or various parts that can be detached and reattached to each other.

[0102] According to a specific embodiment, the body of the gasket device D has an elliptical cross-section recess 15 along an annular recess and has a radial cavity 16 located in the body of the gasket device D, where an optical fiber containing an optical fiber strain sensor is placed, and the radial cavity 16 has the aforementioned elliptical recess as the outer end of the radial cavity 16.

[0103] According to an embodiment, the periphery of the gasket device D has two opposite straight sides and two other opposite arc-shaped sides.

[0104] Fig. 8A , Figure 8B and Figure 8C Three specific design examples of gasket arrangements D developed for steel, titanium and aluminium arrangements respectively are shown by cross-sectional views. Figure 8C The aluminum washers in do not have an oval end cavity.

[0105] According to an embodiment of the washer device D, the first flat surface 11 and the second flat surface 12 of the device body 1 (a washer-shaped or roughly disc-shaped plate) have surface change portions, which increase the friction between the first flat surface and the second flat surface and the following surfaces of the fixing device, and / or the brake caliper support 61, and / or the brake caliper body 60: under the working condition that the device body is installed at one of the above-mentioned fixed joints (i, ii, iii, iv), the above-mentioned first flat surface and the second flat surface are in contact with the said surfaces of the fixing device, and / or the brake caliper support 61, and / or the brake caliper body 60 respectively.

[0106] According to an implementation of the aforementioned embodiment, the aforementioned surface variations of the flat face are obtained by mechanical processing known per se, such as knurling.

[0107] According to another embodiment of the aforementioned embodiment, the aforementioned surface variations of the flat face are obtained by “texturing” the surface by laser technology or equivalent, in a manner known per se, which is applicable to any metal surface, such as steel, titanium or aluminium.

[0108] According to another embodiment of the aforementioned embodiment, the aforementioned surface changes of the flat face are obtained by coating. In this respect, various processes can be used, for example, in the case of aluminum substrates: deposition of diamond particles or silicon carbide, SiC, embedded in electrolytic nickel, or ESD (electro spark deposition) of tungsten carbide, Stellite or aluminum oxide, or other known methods.

[0109] According to various possible embodiments, the aforementioned surface changes of the flat surface are obtained by means of: treatment by mechanical removal, or processing by local deformation of the material (upsetting, knurling) or laser removal (or machining), which may cause the material to vaporize, melt or burn; or various possible coating technologies, for example, based on nanotechnology, very hard nanopowders, which create contact points with high force exchange and therefore high friction, hard inclusions that affect the local formation of "grips" on the surface; or other methods.

[0110] It is noteworthy that the above-described embodiment allows increasing the friction between the sensor and the caliper body or the caliper support, which may be particularly advantageous in the context of the present invention, wherein, as described above, the force acting on the gasket device D determines the deformation of the body of such gasket device and thus determines the force detected by the FBG sensor.

[0111] In particular, the effect of this embodiment is to eliminate or significantly reduce the phenomenon of local variations in strain caused by the reversal of the vehicle's movement: in fact, the friction coefficient on the surface of the joint is increased by the measures taken. By doing so, it is possible to avoid or significantly reduce micro-settings that change the local friction conditions when changing between the forward and reverse directions, thereby changing the strain distribution on the surface of the body of the gasket device. This is very important because if the local conditions change every time the vehicle changes direction, the gasket will deform differently and the output characteristics of the sensor will be less repeatable and non-linear. On the other hand, by virtue of the above-mentioned characteristics of this embodiment, the influence on the sensitive element caused by the braking torque between the forward and reverse conditions is standardized and becomes determined, thereby improving the repeatability and linearity of the sensor output characteristics.

[0112] Now refer to Figures 1 to 14 A system 100 is described for determining the braking torque BT generated by actuation of a vehicle braking system by performing detection at at least one fixed joint (i, ii, iii, iv) between a brake caliper body 60 and a corresponding support 61 or between a brake caliper support 61 and the heads of clamping elements 63, 64 or between axle and wheel suspension.

[0113] The system 100 comprises: at least one washer device D according to any of the preceding embodiments shown above; an optical reading / interrogation unit 4 ; and a remote control unit 20 .

[0114] At least one washer device D is fixed and pressed between the brake caliper body 60 and the brake caliper support 61, or between the brake caliper support 61 and the clamping element head 63, 64, or between the axle and the wheel suspension at at least one corresponding fixed joint (i, ii, iii, iv).

[0115] The optical reading / interrogation unit 4 is optically connected to the at least one gasket device D to receive the aforementioned at least one photon signal L. The optical reading / interrogation unit 4 is configured to generate at least one electrical signal E representing the detected deformation and / or strain S based on the at least one first photon signal L received.

[0116] The remote control unit 20 is connected to the optical reading / interrogation unit 4 to receive the at least one first electrical signal E and is configured to process the at least one first electrical signal E representing the deformation and / or strain S to obtain and provide a measurement value of the braking torque BT.

[0117] According to the embodiment (for example in the case of a device having four and two gaskets, respectively) Figure 3A and Figure 3B ), the system comprises a plurality of gasket devices (D1, D2, D3, D4), each gasket device being located at a corresponding fixed joint (i, ii, iii, iv).

[0118] According to an embodiment, each of the aforementioned gasket devices incorporates a plurality of deformation and / or strain sensors (FBG1 , FBG2, FBG3, FBG4, FBG5, FBG6).

[0119] In this case, the remote control unit 20 is configured to determine the braking torque BT based on a plurality of electrical signals Ejk, each of which is generated by a corresponding photon signal Ljk representing a corresponding deformation and / or strain Sij detected by a corresponding optical fiber strain detection sensor. In the notation used herein, j is an index indicating one of the plurality of washer devices, and k is an index indicating one of the plurality of optical fiber strain sensors included in the washer device.

[0120] According to a preferred embodiment (in terms of functionality, Figure 3A and Figure 3B As shown in the figure, in terms of structure, Fig. 7A , Figure 7B , Fig. 8A , Figure 8B and Figure 8C), the system includes: a first washer device D1, which is located at a first fixed joint (i) between the head of the first fixing bolt 63 and the first part of the caliper support 61; a second washer device D2, which is located at a first fixed joint (ii) between the head of the second fixing bolt 64 and the second part of the caliper support 61; a third washer device D3, which is located at a third fixed joint (iii) between the third part of the caliper support 61 and the caliper body 60; and a fourth washer device D4, which is located at a fourth fixed joint (iv) between the fourth part of the caliper support 61 and the caliper body 60.

[0121] According to the implementation scheme (for example in Figure 4 , Figure 5 , Figure 6 ), one or more optical fiber strain sensors FBG are included in an optical fiber 14 arranged within a tangential peripheral band 13 of a gasket device.

[0122] Each optical fiber strain sensor in such an optical fiber strain sensor FBG is in a radial plane p relative to the gasket (eg, Fig. 8A , Figure 8B , Figure 8C The strain S is obtained from a corresponding optical fiber portion that is tilted at an acute angle or an obtuse angle different from each of the values ​​0°, 90°, 180° and 270° (the plane of the cross section in the sensor) to detect the strain S in a direction different from the normal direction and the tangential direction relative to the gasket, so that the detected strain S depends on both the normal component and the tangential component of the force acting on the sensor.

[0123] According to the implementation mode (for example, Figure 2A and Figure 2B ), the system comprises at least one corresponding optical fiber temperature sensor 5 of the fiber Bragg grating type incorporated in at least one gasket device D.

[0124] The at least one temperature sensor 5 is configured to detect a temperature value T present at a corresponding location and to generate a corresponding at least one auxiliary photon signal Lt representing the measured temperature value T.

[0125] In this case, the optical reading / interrogation unit 4 is optically connected to at least one temperature sensor 5, and the optical reading / interrogation unit 4 is configured to receive the generated at least one auxiliary photon signal Lt and to generate at least one auxiliary electrical signal Et representing the temperature based on the received at least one auxiliary photon signal Lt.

[0126] In this case, the remote control unit 20 is configured to process at least one first electrical signal E and at least one auxiliary electrical signal Et in order to obtain a measured value of the braking force BT taking into account temperature compensation.

[0127] According to an embodiment of the system, the aforementioned at least one temperature sensor 5 comprises a Fiber Bragg Grating manufactured in the same optical fiber 14 as that in which at least one deformation and / or strain sensor FBG is manufactured.

[0128] Depending on the implementation of the system (e.g. Figure 1 ), the optical fiber strain sensor FBG is connected to the optical reading / interrogation unit 4 by means of a first connecting optical fiber 31.

[0129] In this case, the optical reading / interrogation unit 4 is configured to enable the optical fiber temperature sensor by sending light enabling radiation OA via the first connecting optical fiber 31, and the second photon signal L includes an optical spectrum L reflected by the temperature sensor FBG, which reaches the optical reading / interrogation unit 4 through the first connecting optical fiber 31.

[0130] According to another embodiment (for example in Figure 2A ), the optical fiber strain sensor FBG is connected to the optical reading / interrogation unit 4 by means of a first input connecting optical fiber 32 and a second output connecting optical fiber 33.

[0131] In this case, the optical reading / interrogation unit 4 is configured to enable the aforementioned optical fiber temperature sensor FBG by sending light enabling radiation OA via the first input connecting optical fiber 32, and the second photon signal L includes a second optical spectrum L sent by the fiber Bragg grating type temperature sensor FBG, which reaches the optical reading / interrogation unit 4 through the second output connecting optical fiber 33.

[0132] According to another embodiment of the system ( Figure 2A and Figure 2B ), each of the optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) of the device is made in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6) by means of a corresponding Bragg grating.

[0133] Each of the optical fiber strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) is configured to generate a corresponding at least one photon signal of a plurality of photon signals (L1, L2, L3, L4, L5, L6).

[0134] The optical reading / interrogation unit 4 is configured to receive a plurality of photon signals (L1, L2, L3, L4, L5, L6) and generate at least one corresponding electrical signal (E) of a plurality of electrical signals (E1, E2, E3, E4, E5, E6) based on the received plurality of photon signals (L1, L2, L3, L4, L5, L6);

[0135] The remote control unit 20 is configured to process the aforementioned plurality of electrical signals ( E1 , E2 , E3 , E4 , E5 , E6 ) to obtain a measured value of the braking torque BT.

[0136] According to the embodiment, the optical reading / interrogation unit 4 is also configured to send corresponding light-enabled irradiation (OA1, OA2, OA3, OA4, OA5, OA6) at different corresponding working wavelengths (λ1, λ2, λ3, λ4, λ5, λ6) to multiple deformation and / or strain elements by means of wavelength division multiplexing (WDM) transmission technology through the connecting optical fiber 3; and is configured to receive the corresponding optical spectrum reflected by each sensor of the multiple deformation and / or strain sensors (FBG1, FBG2, FBG3, FBG4, FBG5, FBG6) through the connecting optical fiber (3) and distinguish the corresponding optical spectrum by demultiplexing using wavelength division multiplexing (WDM) technology, wherein each of the reflected optical spectra corresponds to a corresponding photon signal (L1, L2, L3, L4, L5, L6).

[0137] According to an embodiment of the system, the control unit 20 includes a processor, which is configured to calculate the braking torque BT based on the aforementioned at least one electrical signal E, or based on the aforementioned at least one electrical signal E and the auxiliary electrical signal Et, or based on the aforementioned multiple electrical signals (Ea, E1, E2, E3, E4, E5, E6; Eij) and the aforementioned at least one auxiliary electrical signal Et with the aid of one or more algorithms executed by one or more software programs.

[0138] According to different embodiments of the system, the remote control unit 20 is configured to determine the braking torque BT based on the electrical signal E representative of the detected strain S by means of the algorithm and / or process previously described for illustrating the method according to the invention.

[0139] refer to Figure 12 to Figure 14 , further illustrative details relating to the reading / interrogation unit 4 will now be provided by way of example.

[0140] According to an embodiment of the system 100 , the optical reading / interrogation unit 4 comprises a broadband optical radiation source 40 , a light circulator 46 and an optoelectronic spectrometer receiver 41 .

[0141] The broadband optical radiation source 40 is configured to deliver a first enabling optical radiation OA or a plurality of second enabling optical radiations OAa, OAb, OAc and / or a second enabling optical radiation OAt.

[0142] The photoelectric spectrometer receiver 41 is configured to select a wavelength and / or multiple wavelengths to be received, and is also configured to: receive the above-mentioned first photon signal L or the above-mentioned multiple first photon signals La, Lb, Lc and convert them into a first electrical signal E, or receive multiple first electrical signals Ea, Eb, Ec, and / or receive the above-mentioned second photon signal Lt and convert the above-mentioned second photon signal Lt into a second electrical signal Et.

[0143] In this embodiment, a technique based on a broad spectrum source and spectrometer is used to interrogate multiplexed FBG sensors (e.g. Fig.12 shown).

[0144] The broad spectrum source may include, for example, a superluminescent diode or a spontaneous emission source (such as a semiconductor optical amplifier or an erbium-doped fiber optical amplifier, etc.), and the broad spectrum source is used to illuminate (through the input port and the through port of the optical circulator 46) the FBG sensors 2a, 2b, 2c, which are characterized in that the reflectivity peaks at different wavelengths (λa, λb, λc) do not overlap each other.

[0145] Different photon signals La, Lb, Lc at their respective wavelengths are reflected back by the FBG sensor (at Fig.12 ), and is coupled to the spectrometer 41 via the output port of the optical circulator 46 .

[0146] The spectrometer 41 is for example a dispersive element, usually made by a phase grating volume, capable of spatially separating different spectral components of the signal. Such spatially separated signal components are coupled to an array of optical receivers capable of generating signals with intensity values ​​corresponding to various wavelengths.

[0147] Each photoreceptor is sensitive to light irradiance corresponding to a well-defined spectral region, thus providing the possibility to reconstruct the entire spectrum within the spectral range of interest.

[0148] According to another embodiment of the system 100 ( Fig.13 As shown in FIG. 4 , the optical reading / interrogation unit 4 includes a tunable light irradiation source 42 , a light circulator 46 and a photodiode photoreceiver 43 .

[0149] The tunable optical irradiation source 42 is configured to deliver at a given time a desired optical irradiation OAn (at a corresponding wavelength λn) among possible first optical enabling irradiations OAa, OAb, OAc or to deliver second optical enabling irradiation OAt at a wavelength λt.

[0150] The emitted optical radiation OAn illuminates (via the input port and the through port of the optical circulator 46 ) the optical fiber containing the FBG sensor and determines the response of the FBG sensor sensitive to the wavelength λ1 , which generates a recto-reflected photon signal Ln coupled to the photodiode receiver 43 via the output port of the optical circulator 46 .

[0151] The photodiode photoreceiver 43 is configured to receive the first photon signal Ln and convert the signal into the first electrical signal En (or similarly receive the second photon signal Lt and convert the signal into the second electrical signal Et).

[0152] In this embodiment, multiplexed FBG sensors in the wavelength domain (WDM) are interrogated using a technique based on tunable lasers and photodiodes.

[0153] According to various embodiments, the tunable optical radiation source 42 is a tunable laser used in a known "flexibly tunable" or "swept wavelength" mode.

[0154] According to another embodiment of the system 100 ( Fig.14 ), the optical reading / interrogation unit 4 is completely made of a single photonic integrated circuit using PIC technology. In this case, this single integrated photonic circuit includes a broadband light radiation source 40, at least one wavelength filtering element 44 and a photoelectric photodiode receiver 43.

[0155] The broadband optical radiation source 40 is configured to deliver a first enabling optical radiation OA or a plurality of second enabling optical radiations OAa, OAb, OAc and / or a second enabling optical radiation OAt.

[0156] The emitted light irradiance (at Fig.14 In the example, light irradiation OAa, OAb, OAc) is irradiated to the optical fiber containing the FBG sensors through the input port and the through port of the optical circulator 46, and each of the FBG sensors reflects the corresponding photon signal La, Lb, Lc. The photon signal WDM given by the sum of the signals La, Lb, Lc at their own different wavelengths is transmitted as a whole to the input of the filter element 44 through the output port of the optical circulator 46.

[0157] At least one wavelength optical filter element 44 can be tuned around the wavelength of the interrogated fiber Bragg grating to select the corresponding photon signal (at Fig.14 In the example, the wavelength λ B The tunable optical filter element 44 can be tuned to different wavelengths so as to select the photon signal reflected by any one of the FBG sensors sequentially or at different times as required.

[0158] The photoelectric photodiode 43 receiver is configured to: receive a photon signal selected from the above photon signals and convert the signal into one or more electrical signals; and / or receive a second photon signal Lt (if selected) and convert the signal into a second electrical signal Et.

[0159] Reference below Fig. 9 , Fig.10 , Fig.11 A brake caliper 6 with a sensor for a vehicle brake system is described.

[0160] The brake caliper with sensor 6 includes a brake caliper body 60 , a brake caliper support 61 , a first fixing bolt 63 , a second fixing bolt 64 , and at least one washer device D according to any of the above-described embodiments.

[0161] At least one washer device D is fixed and compressed between the brake caliper body 60 and the brake caliper support 61 at at least one fixed joint (i, ii, iii, iv) between the brake caliper body 60 and the brake caliper support 61 .

[0162] According to different embodiments, the brake caliper is a fixed or floating brake caliper.

[0163] According to an embodiment, the sensorized caliper 6 also comprises an optical reading / interrogation unit 4 which can be connected to a remote control unit 20 external to the brake caliper.

[0164] The optical reading / interrogation unit 4 is according to the description above.

[0165] In particular, the optical reading / interrogation unit 4 is optically connected to the first photonic connection device 3 to receive at least one photonic signal L, and is configured to determine at least one electrical signal E representing the detected deformation and / or strain S based on the received at least one photonic signal L. The at least one electrical signal E is suitable for being sent to the remote control unit 20.

[0166] According to a preferred embodiment, the brake caliper 6 with a sensor includes: a first washer device D1, which is located at the first fixed joint (i) between the head of the first fixing bolt 63 and the first part of the caliper support 61; a second washer device D2, which is located at the first fixed joint (ii) between the head of the second fixing bolt 64 and the second part of the caliper support 6; a third washer device D3, which is located at the third fixed joint (iii) between the third part of the caliper support 61 and the caliper body 60; and a fourth washer device D4, which is located at the fourth fixed joint (iv) between the fourth part of the caliper support 61 and the caliper body 60.

[0167] According to different possible embodiments, the brake caliper is a fixed or floating disc brake caliper, or a brake caliper with radial and axial connections, or a monolithic or floating caliper, or a hydraulically or electrically actuated caliper.

[0168] As mentioned above, the optical reading / interrogation unit 4 is integrated and / or housed in the sensorized caliper 6. In this case, an electrical signal E is output from the sensorized caliper and directed to a remote control unit.

[0169] According to another embodiment of the system, the optical reading / interrogation unit 4 is located outside the sensored brake caliper 6. In this case, a photon signal L is emitted from the sensored caliper on an optical fiber and directed towards the optical reading / interrogation unit 4.

[0170] According to an embodiment, the brake caliper with sensor comprises a positioning element 62 of the washer device D, which is suitable for holding and positioning one or more washer devices D in the correct position.

[0171] refer to Fig.11 , some additional details are provided here regarding the relationship between the braking torque, the force acting on the washer arrangement and the force acting on the optical fiber strain sensor.

[0172] When a braking torque is applied to the brake rotor, a mechanical action opposite to the braking torque is applied via the connection on the brake caliper body. The complementary action of these actions is thus applied to the wheel hub. The above mechanical actions can be expressed in terms of forces and moments acting at the support joint. The joint between the brake caliper and the wheel hub bolt (i.e., between the brake caliper body portion and the brake caliper support portion) is defined above as (i), (ii), (iii), (iv), as also described in Fig.10 and Fig.11 As shown in .

[0173] consider Fig.11The x, y, z coordinates and joints (i), (ii), (iii), (iv) shown can define the following quantities.

[0174] F n-iii and F n-iv are the normal forces exchanged between the brake caliper and the brake caliper support due to the action of bolts 63 and 64, respectively. n-i and F n-ii is the normal force exchanged between the head of each bolt and the brake caliper support. In addition, the moment of torque on the zy plane (M z-i 、M z-ii 、M z-iii 、M z-iv 、M y-i 、M >y-ii 、M y-iii 、M y-iv ) is generated by the normal force distribution on each contact joint.

[0175] Finally, the torque moments along the x-direction (Mx-i, Mx-ii, Mx-iii, Mx-iv) and the forces in the zy plane (F z-i 、F z-ii 、F z-iii 、F z-iv 、F y-i 、F y-ii 、F y-iii 、F y-iv ) is caused by the friction interaction between the caliper contact surface, the caliper support and the bolt head.

[0176] The sum of the torque contributions of the above-mentioned frictions to the wheel axle represents the effect of the braking torque reaction.

[0177] The present invention also includes a vehicle brake system comprising a plurality of brake calipers 6 with sensors according to any one of the above-described embodiments of sensorized calipers.

[0178] The invention also comprises a vehicle braking system comprising a system 100 for determining a braking torque BT resulting from an implementation of a vehicle braking system according to any of the embodiments described above for determining a braking torque BT.

[0179] The present invention also comprises a method for manufacturing a gasket device D according to any one of the above-described embodiments.

[0180] This manufacturing method includes the following steps: positioning an optical fiber 14 on the side surface of a gasket of a gasket device D, the optical fiber 14 being previously prepared by engraving optical fiber strain sensors (FBG) arranged according to a predetermined spacing; positioning each optical fiber portion engraved with a corresponding strain sensor FBG along the side surface of the gasket at a predetermined inclination angle relative to a radial reference plane p of the gasket; fixing a formed box to the gasket and to the optical fiber to protect and orient the output optical fiber; fixing the optical fiber 14 and the inclined optical fiber portion of the optical fiber 14 including the optical fiber strain sensor FBG on the side band of the gasket and in the output box with an adhesive material; and applying a protective layer around the peripheral side band of the gasket where the optical fiber 14 is arranged.

[0181] According to another embodiment, the above-mentioned manufacturing method includes the following additional steps: modifying the first flat surface 11 and the second flat surface 12 of the device body 1 by means of a surface change portion, which surface change portion is suitable for causing the friction between the above-mentioned first flat surface and the second flat surface and the following surfaces of the fixing device, and / or the support 61 of the brake caliper, and / or the brake caliper body 60: under the working condition that the device body is installed at one of the fixed joints (i, ii, iii, iv), the above-mentioned first flat surface and the second flat surface are in contact with the said surfaces of the fixing device, and / or the support 61 of the brake caliper, and / or the brake caliper body 60 respectively.

[0182] According to different possible embodiments, the above-mentioned surface changes of the first flat surface 11 and the second flat surface 12 are achieved by: mechanical treatment, such as knurling; or "texturing" of the surface using laser technology or similar technology; or surface coating.

[0183] It is noteworthy that the object of the present invention is completely achieved by the above method and system by means of the functional and structural features of the above method and system.

[0184] In practice, the detection washer arrangement shown above makes it possible to detect with good accuracy deformations and / or forces representative of the forces acting at the clamping joint between the brake caliper body and its support and / or between the brake caliper support and the axle, which forces in turn depend simultaneously on the braking torque. In particular, the detection washer arrangement makes it possible to detect the tangential component and the normal component (or more specifically the three vector components) of the forces acting on the washer arrangement.

[0185] Furthermore, such a device, by virtue of its small dimensions and its "washer" shape, can be advantageously and easily inserted between the wheel arrangement and the axle of the vehicle (in particular between the brake caliper and the brake caliper support) using already provided fixing means, such as already provided screws for attaching the brake caliper to the support of the brake caliper, one or more attachment points.

[0186] As indicated above, there are several possible arrangements of the device relative to the brake caliper. On the one hand, this allows versatility of use and thus a variety of structural solutions, and on the other hand, it provides the freedom to achieve different levels of accuracy as required: for example, a solution in which several devices are arranged at different points and in which several fiber optic sensors are present in each device provides the control system with a greater number of detections and corresponding electrical signals, allowing more precise processing and estimation.

[0187] Other advantages of the device according to the invention are compactness, robustness, ease of installation (for example using already provided fixing systems for fixing brake calipers), versatility of use in the context of fixed or floating caliper disc brakes at different points and / or joints and / or junctions of such a system.

[0188] In addition to the advantages described above, there are also unique advantages derived from the use of fiber optic sensors.

[0189] Similar advantages are achieved with the above-described systems and methods.

[0190] The system comprises one or more sensored brake calipers comprising optical fiber sensors optically connected to a reading / interrogation unit (which may be remote or also integrated into the brake caliper) for optoelectronic conversion of strain information, which, advantageously, may also be based on WDM technology.

[0191] The reading / interrogation unit can be manufactured based on different electro-optical technologies.

[0192] Advantageously, such a reading / interrogation unit can be manufactured with the aid of silicon-based photonic technology (eg PIC: Photonics Integrated Circuit), which also allows the unit to be manufactured by integrating it into a brake caliper with a sensor.

[0193] The control unit of the system can therefore determine the braking torque over a wider operating range by temperature compensation.

[0194] The ability to detect strain at multiple points (because a variety of washer detectors can be used very flexibly, each detector comprising, for example, multiple sensors) helps to determine the braking torque more accurately, albeit indirectly.

[0195] Those skilled in the art may make many changes and modifications to the above embodiments, or may replace each element with other functionally equivalent elements to meet possible needs without departing from the scope of the appended claims. All features of one possible embodiment described above may be implemented independently of other described embodiments.

Claims

1. A method for determining the braking torque (BT) resulting from the actuation of a braking system for a vehicle by means of a detection performed at at least one fixed joint (i, ii, iii, iv) between a brake caliper body (60) and a corresponding brake caliper support (61) or between an axle and a wheel suspension, the method comprising the following steps: - inserting at least one washer device (D) at the at least one fixed joint (i, ii, iii, iv) so that: the washer device (D) is fixed and pressed between the brake caliper body (60) and the brake caliper support (61), or between the brake caliper support (61) and the head of the clamping element (63, 64), or between the axle and the wheel suspension, wherein said washer means (D) is susceptible to deformation when exposed to a force, such that: the deformation and / or strain (S) locally present at each point of said washer means (D) represents a force acting at said at least one fixed joint depending on said braking torque (BT), wherein the gasket device (D) is combined with at least one deformation and / or strain sensor at a corresponding detection position, the at least one deformation and / or strain sensor being arranged to detect deformation and / or strain representing three space vector components of the force acting on the gasket device (D) at the detection position, the at least one deformation and / or strain sensor being an optical fiber strain sensor of the fiber Bragg grating type; - detecting, by means of each of at least one of said optical fiber strain sensors, said deformation and / or strain (S) acting locally on the respective said detection location, and generating a respective at least one photon signal representative of the detected deformation and / or strain (S); - receiving at least one of said photon signals by means of an optical reading / interrogation unit (4), said optical reading / interrogation unit (4) being optically connected to at least one of said optical fiber strain sensors; - generating, by said optical reading / interrogation unit (4), at least one first electrical signal representative of said detected local deformation and / or strain (S) based on said received at least one photon signal; - determining said braking torque (BT) based on at least one said first electrical signal representative of said deformation and / or strain (S), wherein one or more of said optical fiber strain sensors are comprised in an optical fiber (14) arranged within a tangential peripheral band (13) of said gasket device (D), and, Each of the optical fiber strain sensors is obtained in a corresponding optical fiber portion tilted at an acute angle or an obtuse angle different from each of the values ​​0°, 90°, 180° and 270° relative to a radial reference plane (p) of the gasket of the gasket device, so as to detect strain in a direction different from the normal direction and the tangential direction relative to the gasket, so that the detected strain depends on both the normal component and the tangential component of the force acting on the optical fiber strain sensor.

2. The method according to claim 1, wherein: The inserting step includes: inserting a plurality of washer devices, each washer device being located at a corresponding fixed joint (i, ii, iii, iv), and each of the washer devices being combined with a plurality of optical fiber strain sensors; And wherein the determining step includes: determining the braking torque (BT) based on a plurality of first electrical signals Ejk, each first electrical signal originating from a corresponding photon signal Ljk representing a corresponding deformation and / or strain detected by a corresponding optical fiber strain sensor, wherein j is an index indicating one of the plurality of washer devices, and k is an index indicating one of the plurality of optical fiber strain sensors included in the washer device.

3. The method according to claim 2, wherein: The insertion steps include: - inserting a first washer device (D1) at a first fixing joint between the head of a first fixing bolt and a first portion of said brake caliper support (61); - inserting a second washer means (D2) at the first fixing joint between the head of the second fixing bolt and the second portion of the brake caliper support (61); - inserting a third washer device (D3) at a third fixed joint between a third portion of the brake caliper support (61) and the brake caliper body (60); - inserting a fourth washer device (D4) at a fourth fixed joint between a fourth portion of the brake caliper support (61) and the brake caliper body (60).

4. The method according to claim 2, wherein: The insertion steps include: - inserting a washer device at the fixed joint between a portion of the brake caliper support (61) and the brake caliper body (60); - inserting a further washer arrangement at a further fixed joint between a further portion of the brake caliper support (61) and the brake caliper body (60).

5. The method according to any one of claims 1 to 4, wherein: The method comprises the following additional steps: - incorporating in at least one of said gasket devices (D) a respective at least one optical fiber temperature sensor (5) of the Fiber Bragg Grating type; - detecting, by means of each of the at least one optical fiber temperature sensor (5), a temperature value (T) existing at a respective location, and generating a respective at least one auxiliary photon signal (Lt) representative of the measured temperature value (T); - receiving at least one of said auxiliary photon signals (Lt) generated by said optical reading / interrogation unit (4) optically connected to said at least one optical fiber temperature sensor (5); - generating, by said optical reading / interrogation unit (4), at least one auxiliary electrical signal (Et) representative of the temperature, based on at least one said auxiliary photonic signal (Lt) received; And wherein the determination step comprises: processing at least one of the first electrical signals and at least one of the auxiliary electrical signals (Et) to obtain a temperature-compensated measurement value of the braking torque (BT), and wherein the at least one optical fiber temperature sensor (5) comprises a fiber Bragg grating manufactured in the same optical fiber (14) as that used to manufacture at least one of the optical fiber strain sensors.

6. The method according to claim 2, wherein: The optical fiber strain sensor is connected to the optical reading / interrogation unit (4) by means of a first connecting optical fiber (31), wherein the optical reading / interrogation unit (4) is configured to enable the optical fiber strain sensor by sending an enabling light irradiation (OA) via the first connecting optical fiber (31), and wherein the photon signal comprises an optical spectrum (L) reflected by the optical fiber strain sensor of the fiber Bragg grating type, the optical spectrum (L) reaching the optical reading / interrogation unit (4) via the first connecting optical fiber (31).

7. The method according to any one of claims 1 to 4, wherein: The optical fiber strain sensor is connected to the optical reading / interrogation unit (4) by means of a first input connecting optical fiber (32) and a second output connecting optical fiber (33), wherein the optical reading / interrogation unit (4) is configured to enable the optical fiber strain sensor by sending an enabling optical irradiation (OA) via the first input connection optical fiber (32), And wherein the photon signal comprises an optical spectrum (L) transmitted by the optical fiber strain sensor of the fiber Bragg grating type, the optical spectrum (L) reaching the optical reading / interrogation unit (4) through the second output connecting optical fiber (33).

8. The method according to any one of claims 1 to 4, wherein: Each of the optical fiber strain sensors of the gasket device is made by means of a corresponding Bragg grating in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6); - The step of generating at least one corresponding photon signal comprises: generating a plurality of corresponding photon signals; - The receiving step comprises: receiving a plurality of said photon signals by said optical reading / interrogation unit (4); - the step of generating at least one first electrical signal by said optical reading / interrogation unit (4) comprises: generating a corresponding plurality of first electrical signals based on a plurality of said received photon signals; - The processing step comprises: processing a plurality of said first electrical signals to obtain a measurement value of said braking torque (BT).

9. The method according to claim 6, wherein: The method further comprises the following additional steps: - sending corresponding enabling light radiation at different corresponding central working wavelengths (λ1, λ2, λ3, λ4, λ5, λ6) to a plurality of said optical fiber strain sensors by said optical reading / interrogation unit (4) via connecting optical fibers (3) by means of wavelength division multiplexing transmission technology; - receiving a corresponding optical spectrum reflected by each of the plurality of optical fiber strain sensors through the connecting optical fiber (3) and distinguishing the corresponding optical spectrum by demultiplexing using wavelength division multiplexing technology, wherein each of the reflected optical spectra corresponds to a corresponding photon signal.

10. The method according to claim 8, wherein: The method comprises, before the determination step, a step of sending at least one of the first electrical signal and / or the auxiliary electrical signal (Et) to a control unit (20); And wherein the determining step comprises: - The braking torque (BT) is calculated by a processor of the control unit (20) based on at least one of the first electrical signals, or based on at least one of the first electrical signals and the auxiliary electrical signal (Et), or based on a plurality of the first electrical signals and at least one of the auxiliary electrical signals (Et) with the aid of one or more algorithms executed by one or more software programs.

11. The method according to claim 10, wherein: The calculation step comprises: calculating said braking torque (BT) by means of a predetermined non-linear relationship between said braking torque and a deformation and / or strain detected by at least one said optical fiber strain sensor incorporated at a corresponding position in said washer device (D), The predetermined non-linear relationship is represented by a computerized model or look-up table stored so as to be accessible by the processor of the control unit (20), Said predetermined non-linear relationship is determined by means of a testing and / or characterization and / or calibration phase performed after at least one washer device (D) containing at least one said optical fiber strain sensor has been positioned and fixed at a respective fixed joint between said brake caliper body and said brake caliper support.

12. The method according to claim 11, wherein: The calculation steps include: - defining for each of the four washer devices a respective nonlinear model (NM1, NM2, NM3, NM4), said nonlinear model (NM1, NM2, NM3, NM4) being suitable for determining three vector components of a respective vector force acting on said washer device, said three vector components comprising a triaxial force (F1, F2, F3, F4); - calculating the braking torque (BT) based on the three-axis forces (F1, F2, F3, F4) determined by the four nonlinear models.

13. The method according to claim 12, wherein: The steps to define a nonlinear model for the gasket assembly include: -Define the basic nonlinear model with the help of FEM simulation; - refining the parameters of the nonlinear model, by means of an initial calibration phase, based on the measured values ​​of the strains detected by the respective optical fiber strain sensors of the gasket device (Sij) and on simultaneous measurements of the physical quantities generating the strains under known experimental conditions, The physical quantity includes: the braking torque (BT); the preload due to the tension (V) of the fixing screws during assembly and / or the pressure (P) applied by the brake caliper.

14. The method according to any one of claims 1 to 4, wherein: The determining step comprises obtaining a dynamic measurement of a real-time trend of the braking torque (BT) based on the detected temporal evolution of the deformation and / or strain.

15. A gasket device (D) for detecting deformation and / or strain, the gasket device (D) comprising: - a device body (1) in the form of a washer or a disk-like plate extending mainly along a radial reference plane (p), the device body (1) having a first flat face (11) and a second flat face (12) parallel to the radial reference plane (p), the device body (1) being suitable for being placed in close contact with a surface of a fixing means and / or a brake caliper support (61) and / or a brake caliper body (60), so that the device body (1) is mounted at a fixed joint (i, ii, iii, iv) between the brake caliper body (60) and the brake caliper support (61) or between the brake caliper support (61) and the head of a clamping element (63, 64), wherein the device body (1) has a tangential peripheral band and / or a recess extending along a portion or periphery of the device body (1) of the gasket device (D), wherein the device body (1) is susceptible to deformation when exposed to a force, such that: the deformation and / or strain (S) locally present in each point of the gasket device (D) represents the force acting on the gasket device (D); - an optical fiber (14), said optical fiber (14) being arranged along said tangential peripheral band and / or recess, or said optical fiber (14) being arranged at said tangential peripheral band and / or recess, wherein said optical fiber (14) comprises one or more deformation and / or strain sensors, said deformation and / or strain sensors being optical fiber strain sensors of the fiber Bragg grating type, wherein each of said one or more optical fiber strain sensors is configured to detect a local deformation and / or strain acting on a corresponding detection position, and to generate a corresponding at least one photon signal representing the detected deformation and / or strain (S), wherein each of the one or more optical fiber strain sensors is obtained in a corresponding optical fiber portion tilted with respect to a radial reference plane (p) at an acute or obtuse tilt angle different from each of the values ​​0°, 90°, 180° and 270°, so as to detect strains in a direction different from the normal direction, from the tangential direction and from the tangential or radial direction relative to the radial reference plane (p) of the gasket of the gasket device, so that the detected strain depends on both the normal component and the tangential component of the force acting on the one or more optical fiber strain sensors and / or on each of the three space vector components of the force acting on the one or more optical fiber strain sensors; - wherein said optical fiber (14) comprising one or more said optical fiber strain sensors is adapted to transmit at least one said photonic signal generated by at least one said optical fiber strain sensor and to receive at least one enabling optical irradiation (OA) for the corresponding at least one optical fiber strain sensor.

16. The gasket device (D) according to claim 15, wherein The tilt angle is ±30°.

17. A gasket device (D) according to claim 15 or 16, wherein: The optical fiber comprises a plurality of optical fiber strain sensors arranged along a peripheral extension of the optical fiber (14) and / or spaced equidistantly, Each of the optical fiber strain sensors of the gasket device (D) is made in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6) by means of a corresponding Bragg grating, and each of the optical fiber strain sensors of the gasket device (D) is suitable for: being excited by means of corresponding light radiation belonging to the total excitation in wavelength division multiplexing at the corresponding central operating wavelength; and generating a transmitted or reflected optical spectrum that forms the corresponding photon signal.

18. The gasket device (D) according to claim 17, wherein The plurality of optical fiber strain sensors include six optical fiber strain sensors, or include six optical fiber strain sensors and one optical fiber temperature sensor (5).

19. The gasket device (D) according to claim 15 or 16, wherein: The geometric structure of the device body of the washer device (D) and the material of the device body of the washer device (D) are selected based on the requirements of ensuring the mechanical strength for the axial fixed preload and the shear force generated by the braking action and optimizing the deformation of the device body of the washer device (D) without reaching the critical structural strain.

20. The gasket device (D) according to claim 19, wherein The device body of the washer device (D) is made of steel, or titanium, or aluminum, and / or where The device body (1) of the gasket device (D) comprises a plurality of parts connected together and / or a plurality of parts which can be detached from and reattached to each other.

21. The gasket device (D) according to claim 19, wherein The device body of the gasket device (D) has an elliptical cross-section recess (15) along the annular recess in which the optical fiber containing one or more optical fiber strain sensors is located and has a radial cavity (16) located in the device body of the gasket device (D), wherein the elliptical cross-section recess serves as an outer end of the radial cavity (16), And wherein the periphery of the gasket device (D) has two opposite straight sides and two other opposite arc-shaped sides.

22. The gasket device (D) according to claim 15 or 16, wherein: The first flat surface (11) and the second flat surface (12) of the device body (1) of the washer device have surface changes, which are suitable for increasing the friction between the first flat surface and the second flat surface and the following surfaces of the fixing device and / or the brake caliper support (61) and / or the brake caliper body (60): under the working condition that the device body (1) is mounted at one of the fixing joints (i, ii, iii, iv), the surfaces of the fixing device and / or the brake caliper support (61) and / or the brake caliper body (60) are in contact with the first flat surface and the second flat surface respectively.

23. The gasket device (D) according to claim 22, wherein The surface changes of the first flat surface (11) and the second flat surface (12) are obtained by: - mechanical treatment comprising knurling; or - texturing of the surface obtained with the aid of laser technology; or -Coating.

24. A system (100) for determining the braking torque (BT) resulting from the actuation of a braking system for a vehicle by means of a detection carried out at at least one fixed joint (i, ii, iii, iv) between a brake caliper body (60) and a corresponding brake caliper support (61) or between said brake caliper support (61) and the head of a clamping element (63, 64) or between an axle and a wheel suspension, in, The system (100) comprises: - at least one washer device (D) according to any one of claims 15 to 23, at least one washer device (D) being fixed and pressed between the brake caliper body (60) and the brake caliper support (61), or between the brake caliper support (61) and the head of a clamping element (63, 64), or between the axle and the wheel suspension at the respective at least one fixed joint (i, ii, iii, iv); - an optical reading / interrogation unit (4) optically connected to at least one gasket device (D) to receive at least one of said photon signals, The optical reading / interrogation unit (4) is configured to generate at least one first electrical signal representative of the detected deformation and / or strain (S) based on the received at least one photon signal; - a remote control unit (20), said remote control unit (20) being connected to said optical reading / interrogation unit (4) to receive at least one of said first electrical signals, The remote control unit (20) is configured to process at least one of the first electrical signals representing the deformation and / or strain (S) to obtain and provide a measurement value of the braking torque (BT).

25. The system (100) of claim 24, wherein: The inserting step includes inserting a plurality of washer devices, each washer device being located at a corresponding fixed joint (i, ii, iii, iv) of the washer devices, wherein each of the washer devices incorporates a plurality of the optical fiber strain sensors; And wherein the remote control unit (20) is configured to determine the braking torque (BT) based on a plurality of first electrical signals Ejk, each first electrical signal Ejk originating from a corresponding photon signal Ljk representing a corresponding deformation and / or strain detected by a corresponding optical fiber strain sensor, wherein j is an index indicating one of the plurality of washer devices, and k is an index indicating one of the plurality of optical fiber strain sensors included in the washer device.

26. The system (100) of claim 25, wherein: The system (100) comprises: - a first washer device (D1) located at a first fixed joint between the head of a first fixing bolt and a first portion of the brake caliper support (61); - a second washer means (D2) located at a first fixed joint between the head of a second fixing bolt and the second portion of the brake caliper support (61); - a third washer device (D3) located at a third fixed joint between a third portion of the brake caliper support (61) and the brake caliper body (60); - a fourth washer device (D4) located at a fourth fixed joint between a fourth portion of the brake caliper support (61) and the brake caliper body (60).

27. The system (100) according to any one of claims 24 to 26, wherein: One or more of said optical fiber strain sensors are comprised in an optical fiber (14) arranged within a tangential peripheral band (13) of said gasket device (D), And, each of the optical fiber strain sensors is obtained in a corresponding optical fiber portion tilted at an acute angle or an obtuse angle different from each of the values ​​0°, 90°, 180° and 270° relative to a radial reference plane (p) of the gasket of the gasket device, so as to detect strain in a direction different from the normal direction and the tangential direction relative to the gasket, so that the detected strain depends on both the normal component and the tangential component of the force acting on the optical fiber strain sensor.

28. The system (100) according to any one of claims 24 to 26, wherein: The system (100) further comprises a respective at least one optical fiber temperature sensor (5) of the fiber Bragg grating type incorporated in at least one of the gasket devices (D); wherein each of the at least one optical fiber temperature sensor (5) is configured to detect a temperature value (T) existing at a corresponding position and to generate a corresponding at least one auxiliary photon signal (Lt) representing the measured temperature value (T); wherein the optical reading / interrogation unit (4) is optically connected to the at least one optical fiber temperature sensor (5), and the optical reading / interrogation unit (4) is configured to receive the generated at least one auxiliary photon signal (Lt) and to generate at least one auxiliary electrical signal (Et) representing the temperature based on the received at least one auxiliary photon signal (Lt); And wherein the remote control unit (20) is configured to process at least one of the first electrical signal and at least one of the auxiliary electrical signal (Et) to obtain a measured value of the braking torque (BT) taking into account temperature compensation.

29. The system (100) of claim 28, wherein: The at least one optical fiber temperature sensor (5) comprises a fiber Bragg grating manufactured in the same optical fiber (14) as the at least one optical fiber strain sensor.

30. The system (100) according to any one of claims 24 to 26, wherein: The optical fiber strain sensor is connected to the optical reading / interrogation unit (4) by means of a first connecting optical fiber (31), wherein the optical reading / interrogation unit (4) is configured to enable the optical fiber strain sensor by sending an enabling light irradiation (OA) via the first connecting optical fiber (31), and wherein the photon signal comprises an optical spectrum (L) reflected by the optical fiber strain sensor of the fiber Bragg grating type, the optical spectrum (L) reaching the optical reading / interrogation unit (4) via the first connecting optical fiber (31).

31. The system (100) according to any one of claims 24 to 26, wherein: The optical fiber strain sensor is connected to the optical reading / interrogation unit (4) by means of a first input connecting optical fiber (32) and a second output connecting optical fiber (33), wherein the optical reading / interrogation unit (4) is configured to enable the optical fiber strain sensor by sending an enabling optical irradiation (OA) via the first input connection optical fiber (32), And wherein the photon signal comprises an optical spectrum (L) transmitted by the optical fiber strain sensor of the fiber Bragg grating type, the optical spectrum (L) reaching the optical reading / interrogation unit (4) through the second output connecting optical fiber (33).

32. The system (100) according to any one of claims 24 to 26, wherein: Each of the optical fiber strain sensors of the gasket device is made by means of a corresponding Bragg grating in a manner associated with a corresponding central operating wavelength (λ1, λ2, λ3, λ4, λ5, λ6); - wherein each of the optical fiber strain sensors is configured to generate a corresponding at least one photon signal of a plurality of photon signals; wherein the optical reading / interrogation unit (4) is configured to receive a plurality of the photon signals, and to generate a corresponding at least one first electrical signal among a plurality of first electrical signals based on the received plurality of the photon signals; And wherein the remote control unit (20) is configured to process a plurality of the first electrical signals to obtain a measurement value of the braking torque (BT).

33. The system (100) of claim 32, wherein: The optical reading / interrogation unit (4) is further configured to: - sending corresponding enabling light radiation at different corresponding working wavelengths (λ1, λ2, λ3, λ4, λ5, λ6) to a plurality of said optical fiber strain sensors via connecting optical fibers (3) by means of wavelength division multiplexing transmission technology; - receiving a corresponding optical spectrum reflected by each of the plurality of optical fiber strain sensors through the connecting optical fiber (3) and distinguishing the corresponding optical spectrum by demultiplexing using wavelength division multiplexing technology, wherein each of the reflected optical spectra corresponds to a corresponding photon signal.

34. The system (100) of claim 28, wherein: The control unit (20) includes a processor, which is configured to calculate the braking torque (BT) based on at least one of the first electrical signals, or based on at least one of the first electrical signals and the auxiliary electrical signal (Et), or based on multiple of the first electrical signals and at least one of the auxiliary electrical signals (Et) with the aid of one or more algorithms executed by one or more software programs.

35. The system (100) according to any one of the preceding claims 24 to 26, wherein: The optical reading / interrogation unit (4) comprises: a broadband optical radiation source (40) configured to transmit at least one first enabling optical radiation and / or second enabling optical radiation; - an optoelectronic spectrometer receiver (41), the optoelectronic spectrometer receiver (41) being configured to select a wavelength to be received and further configured to: receive each first photon signal of at least one first photon signal generated in association with at least one first enabling optical radiation, respectively, and convert each first photon signal into the first electrical signal; and / or, receive a second photon signal generated in association with the second enabling optical radiation, and convert the second photon signal into a second electrical signal; Or wherein the optical reading / interrogation unit (4) comprises: - a tunable optical radiation source (42) configured to transmit at least one first enabling optical radiation and / or second enabling optical radiation, each enabling optical radiation being at a desired respective wavelength; - a photodiode photoelectric receiver (43), the photodiode photoelectric receiver (43) being configured to: receive a first photon signal and convert the first photon signal into the first electrical signal; and / or receive a second photon signal and convert the second photon signal into a second electrical signal; or wherein the optical reading / interrogation unit (4) is entirely made of a single integrated photonic circuit implementing photonic integrated circuit technology, and wherein the single integrated photonic circuit comprises: a broadband optical radiation source (40) configured to transmit at least one first enabling optical radiation and / or second enabling optical radiation; - at least one optical wavelength filtering element (44) which can be tuned to the wavelength of the interrogated fiber Bragg grating to select the corresponding photon signal; - a photodiode photoreceiver (43), which is configured to: receive a photon signal selected from at least one first photon signal and convert the selected photon signal into the first electrical signal; and / or, if a second photon signal is selected, receive the second photon signal and convert the second photon signal into a second electrical signal.

36. A brake caliper (6) with a sensor for a vehicle braking system, the brake caliper (6) with a sensor comprising: -brake caliper body (60); - a brake caliper support (61); - a first fixing bolt and a second fixing bolt; - at least one washer device (D) according to any one of claims 15 to 23, at least one washer device (D) being fixed and pressed between the brake caliper body (60) and the brake caliper support (61) in a manner corresponding to at least one fixed joint (i, ii, iii, iv) located between the brake caliper body (60) and the brake caliper support, wherein the brake caliper is a fixed caliper or a floating caliper.

37. The brake caliper (6) with sensor according to claim 36, wherein: The brake caliper (6) further comprises: an optical reading / interrogation unit (4) connectable to a remote control unit (20) located outside the brake caliper, The optical reading / interrogation unit (4) is optically connected to the first photonic connection device to receive at least one of the photonic signals, The optical reading / interrogation unit (4) is configured to generate at least one first electrical signal representative of the detected deformation and / or strain (S) based on at least one received photon signal, the at least one first electrical signal being suitable for being sent to the remote control unit (20).

38. The brake caliper (6) with sensor according to claim 36 or 37, wherein: The brake caliper (6) comprises: - a first washer device (D1) located at a first fixed joint between the head of a first fixing bolt and a first portion of the brake caliper support (61); - a second washer means (D2) located at a second fixing junction between the head of a second fixing bolt and a second portion of the brake caliper support (61); - a third washer device (D3) located at a third fixed joint between a third portion of the brake caliper support (61) and the brake caliper body (60); - a fourth washer device (D4) located at a fourth fixed joint between a fourth portion of the brake caliper support (61) and the brake caliper body (60).

39. A braking system for a vehicle, wherein: The brake system comprises a plurality of brake calipers (6) with sensors according to any one of claims 36 to 38, Alternatively, the braking system comprises: a system (100) according to any one of claims 24 to 33.

40. A manufacturing method for manufacturing a gasket device (D) according to any one of claims 15 to 23, wherein: The manufacturing method comprises the following steps: - positioning an optical fiber (14) on the side surface of the gasket of the gasket device (D), the optical fiber (14) previously prepared by engraving the optical fiber strain sensor arranged according to a predetermined pitch; - positioning each optical fiber portion engraved with a respective optical fiber strain sensor along a lateral surface of the gasket in a respective tilted direction at a predetermined tilt angle relative to a radial reference plane (p) of the gasket; - fixing a shaped box to the gasket and to the optical fiber to protect and orient the output optical fiber; - fixing the optical fiber (14) and the inclined optical fiber portion of the optical fiber (14) including the optical fiber strain sensor on the side bands of the gasket and in the output box with an adhesive material; - A protective layer is applied around the peripheral side band of the gasket where the optical fibers (14) are arranged.

41. The manufacturing method according to claim 40, wherein: The manufacturing method comprises the following additional steps: The first flat surface (11) and the second flat surface (12) of the device body (1) of the washer device are modified by means of a surface change portion, the surface change portion being suitable for increasing the friction between the first flat surface and the second flat surface and the following surfaces of the fixing device and / or the brake caliper support (61) and / or the brake caliper body (60): under the working condition that the device body (1) of the washer device is mounted at one of the fixed joints (i, ii, iii, iv), the surfaces of the fixing device and / or the brake caliper support (61) and / or the brake caliper body (60) respectively contacting the first flat surface and the second flat surface.

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