A speed torque measurement device and measurement method based on fiber grating sensor

Abstract

The present invention relates to a speed torque measuring device and a measuring method based on fiber grating sensing, wherein the device includes two follower wheels and multiple sensors, and the sensor includes a housing, a permanent magnet, a transmission part and a fiber grating. By installing the follower wheel on the rotating part to be measured, the follower wheel rotates with the rotating part, and the convex part on the follower wheel drives the permanent magnet in the sensor to vibrate along the radial direction of the follower wheel. The permanent magnet is transmitted by the transmission part to cause the fiber grating to undergo periodic strain, so that the light conducted in the fiber grating will change, and the change law can reflect the movement law of the permanent magnet, that is, the rotation of the follower wheel. By setting multiple sensors according to certain rules and obtaining wavelength signals collected by multiple sensors, the speed, torque and other information of the rotating part to be measured can be analyzed.

Description

Technical Field

[0001] The invention relates to the technical field of fiber grating sensing, and in particular to a rotation speed torque measuring device and a measuring method based on fiber grating sensing. Background Art

[0002] Rotating machinery is widely used in industrial production and plays an important role in various fields. However, rotating machinery often fails during operation due to internal or external influences, causing the equipment to reduce its intended function or even fail, which may cause serious accidents. Therefore, it is very necessary to measure the speed and torque of rotating machinery during operation.

[0003] At present, contact sensors (such as strain gauges and accelerometers as sensing methods) can be used for detection in industry, but contact sensors have problems such as difficult signal transmission and poor anti-interference ability. In addition, as the number of measuring points increases, the power supply and signal lines of existing contact sensors increase accordingly, causing difficulties in routing the measurement system.

[0004] Therefore, there is an urgent need for a measuring device and a measuring method that can effectively measure the rotation speed and torque of a rotating machine. Summary of the invention

[0005] In view of this, it is necessary to provide a speed and torque measurement device and a measurement method based on fiber grating sensing to solve the problem of how to measure the speed and torque of a rotating machine.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a speed torque measurement device based on fiber grating sensing, comprising:

[0008] Two follower wheels are coaxially connected to the rotating member to be tested, and the circumference of the follower wheels is evenly provided with a plurality of convex parts with magnetic force;

[0009] A plurality of sensors, each two of the sensors form a group, the two sensors in each group are arranged along the axial direction of the follower wheel and correspond to two follower wheels respectively, and the plurality of groups of sensors are arranged around the follower wheel;

[0010] The sensor includes: a shell, a permanent magnet, a transmission part and a fiber grating, wherein the permanent magnet is slidably arranged on the shell, one end of the permanent magnet faces the circumference of the follower wheel, the other end of the permanent magnet, the transmission part and one end of the fiber grating are connected in sequence, and the other end of the fiber grating is connected to the shell.

[0011] Furthermore, the transmission part includes a piston, a sleeve and an elastic deformation body, the other end of the permanent magnet is connected to the piston, the piston is inserted into one end of the sleeve, the sleeve is connected to the shell, the elastic deformation body is connected to the other end of the sleeve, the elastic deformation body, the sleeve and the piston together form a sealed space and are filled with inert gas, and the elastic deformation body is connected to one end of the optical fiber Bragg grating.

[0012] Furthermore, it also includes a sensitivity enhancement lever, which is rotatably connected to the shell, and the lever includes a driving end and a driven end, the driving end is connected to the other end of the elastic deformation body, the driven end is connected to a section of the fiber grating, and the other end of the fiber grating is connected to the shell.

[0013] Furthermore, the sensitivity enhancement lever includes a first rod body and a second rod body, the first rod body is L-shaped, one end of the first rod body is rotatably connected to the inner wall of the outer shell, the middle part of the first rod body is connected to the other end of the elastic deformation body, the other end of the first rod body is rotatably connected to the middle part of the second rod body, one end of the second rod body is rotatably connected to the inner wall of the outer shell, and the other end of the second rod body is connected to one end of the optical fiber Bragg grating.

[0014] In a second aspect, the present invention further provides a rotation speed measurement method, using any of the above-mentioned rotation speed torque measurement devices based on fiber grating sensing, the method comprising:

[0015] Acquire multiple groups of wavelength signals through the multiple sensors;

[0016] Obtaining a plurality of rotation periods according to the wavelength signal and the number of the convex portions;

[0017] According to the plurality of rotation cycles, the rotation speed of the rotating member is obtained.

[0018] Furthermore, the obtaining of a plurality of rotation periods according to the wavelength signal and the number of the convex portions includes:

[0019] Obtaining a zero-crossing vector group according to the moment when the falling edge of each wavelength signal crosses zero;

[0020] According to the zero-crossing vector group, a convex interval period vector group is obtained;

[0021] According to the convex portion interval periodic vector group, a plurality of rotation periods are obtained.

[0022] Further, obtaining the rotation speed of the rotating part according to the plurality of rotation cycles includes:

[0023] Optimizing the rotation period;

[0024] According to the optimized rotation period, the rotation speed of the rotating part is obtained.

[0025] In a third aspect, the present invention further provides a torque measurement method, using any of the above-mentioned speed torque measurement devices based on fiber grating sensing, the method comprising:

[0026] Acquire multiple groups of wavelength signals through the multiple sensors;

[0027] Obtaining a phase difference value according to the wavelength signal;

[0028] The torque of the rotating member is obtained according to the phase difference.

[0029] Further, obtaining the phase difference value according to the wavelength signal includes:

[0030] Obtaining a phase measurement vector group according to the moment when the falling edge of each wavelength signal passes through zero;

[0031] A phase difference value is obtained according to the phase measurement vector group.

[0032] Further, obtaining the torque of the rotating part according to the phase difference value includes:

[0033] Optimizing the phase difference value;

[0034] According to the optimized phase difference value, the shaft torsion is obtained;

[0035] The torque of the rotating member is obtained according to the shaft torsion.

[0036] The present invention provides a speed torque measuring device and method based on fiber grating sensing. By installing a follower wheel on the rotating part to be measured, the follower wheel rotates with the rotating part. The convex part on the follower wheel drives the permanent magnet in the sensor to vibrate along the radial direction of the follower wheel (the permanent magnet moves due to the attraction or repulsion of the convex part. When the follower wheel rotates, the convex part sweeps across the permanent magnet at intervals, causing the force on the permanent magnet to change periodically, thereby achieving vibration). The permanent magnet is transmitted through the transmission part to cause the fiber grating to undergo periodic strain, so that the light transmitted in the fiber grating will change, and the change law can reflect the movement law of the permanent magnet, that is, the rotation of the follower wheel. By setting multiple sensors according to certain rules and obtaining wavelength signals collected by multiple sensors, the speed, torque and other information of the rotating part to be measured can be analyzed. Compared with the existing technology, the present invention fully utilizes the advantages of fiber Bragg grating such as anti-electromagnetic interference, corrosion resistance, high temperature resistance, small size, light weight, and easy distributed dynamic measurement. It also has a simple structure and is convenient for on-site installation and wiring. Most importantly, it can effectively and accurately measure the rotational speed and torque, and has a good application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic structural diagram of an embodiment of a speed and torque measurement device based on fiber grating sensing provided by the present invention;

[0038] Figure 2 A schematic diagram of the structure of a sensor in an embodiment of a rotation speed and torque measurement device based on fiber grating sensing provided by the present invention;

[0039] Figure 3 A method flow chart of an embodiment of a rotation speed measurement method provided by the present invention;

[0040] Figure 4 This is a method flow chart of an embodiment of a torque measurement method provided by the present invention. DETAILED DESCRIPTION

[0041] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0042] In the description of the present application, “plurality” means two or more than two, unless otherwise clearly and specifically defined.

[0043] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0044] The present invention provides a speed torque measurement device based on fiber grating sensing and a test method, which are respectively described below.

[0045] Combination Figure 1 and Figure 2 As shown, a specific embodiment of the present invention discloses a speed torque measuring device based on fiber grating sensing, the device includes two follower wheels 1 and multiple sensors 2, wherein the two follower wheels 1 are coaxially connected to the rotating part to be measured, the circumferential surface of the follower wheel 1 is evenly provided with multiple convex portions with magnetic force, every two of the multiple sensors 2 form a group, the two sensors 2 in each group are arranged along the axial direction of the follower wheel 1, and correspond to the two follower wheels 1 respectively, and multiple groups of sensors 2 are arranged around the follower wheel 1.

[0046] Each of the sensors 2 further comprises: a permanent magnet 21, a transmission part 22, a fiber Bragg grating 23 and a housing 24, wherein the permanent magnet 21 is slidably arranged in the housing 24, one end of the permanent magnet 21 faces the circumference of the follower wheel 1, the other end of the permanent magnet 21, the transmission part 22 and one end of the fiber Bragg grating 23 are connected in sequence, and the other end of the fiber Bragg grating 23 is fixedly connected to the housing 24 and is used to output a wavelength signal.

[0047] The present invention provides a speed torque measuring device and a measuring method based on fiber grating sensing. By installing a follower wheel 1 on a rotating part to be measured, the follower wheel 1 rotates with the rotating part. The convex part on the follower wheel 1 drives the permanent magnet 21 in the sensor 2 to vibrate along the radial direction of the follower wheel 1 (the permanent magnet 21 moves due to the attraction or repulsion of the convex part. When the follower wheel 1 rotates, the convex part sweeps across the permanent magnet 21 at intervals, causing the force on the permanent magnet 21 to change periodically, thereby achieving vibration). The permanent magnet 21 is transmitted through the transmission part 22 to cause the fiber grating 23 to undergo periodic strain. In this way, the light conducted in the fiber grating 23 will change, and the change law can reflect the movement law of the permanent magnet 21, that is, the rotation of the follower wheel 1. By setting a plurality of sensors 2 according to a certain rule and obtaining the wavelength signals collected by the plurality of sensors 2, the speed, torque and other information of the rotating part to be measured can be analyzed.

[0048] In this embodiment, the two follower wheels 1 can be directly connected to the rotating member to be tested and rotate along with the rotating member. The deformation caused by the twisting of the rotating member to be tested will occur between the positions of the two follower wheels 1 .

[0049] As a preferred embodiment, the follower wheel 1 in this embodiment is implemented by a gear with magnetic force, and the gear teeth of the gear are the convex part of the follower wheel 1. In practice, other parts with convex parts can also be used. The convex part and the peripheral surface between the two convex parts can be provided with different magnetic poles respectively to realize the oscillating motion of the permanent magnet 21.

[0050] Multiple sensors 2 can be installed on other structures near the follower wheel 1 by existing means such as brackets, without being connected to rotating parts. In a preferred embodiment, the transmission part 22 in the sensor 2 includes a piston 221, a sleeve 222 and an elastic deformation body 223, the other end of the permanent magnet 21 is connected to the piston 221, the piston 221 is inserted into one end of the sleeve 222, the sleeve 222 is connected to the housing 24, the elastic deformation body 223 is connected to the other end of the sleeve 222, the elastic deformation body 223, the sleeve 222 and the piston 221 together form a sealed space and are filled with inert gas, and the elastic deformation body 223 is connected to one end of the fiber grating 23.

[0051] When the rotating part to be measured rotates, the follower wheel 1 rotates accordingly, and the convex part of the follower wheel 1 causes the air gap between the permanent magnet 21 of the sensor 2 and the follower wheel 1 to change, thereby driving the piston 221 to reciprocate in the sleeve 222, causing the volume of the enclosed inert gas to change, and the air pressure to change, thereby causing the elastic deformable body 223 to deform, thereby driving the fiber Bragg grating 23 to generate strain, and the expansion and contraction amount of the fiber Bragg grating 23 is linearly related to the movement displacement of the piston 221

[0052] Further, as a preferred embodiment, the elastic deformation body 223 in this embodiment is an elastic bellows, one end of which is sealed and connected to the other end of the sleeve 222, and the other end of which is sealed and connected to the fiber grating 23. In practice, other existing parts that can deform according to the air pressure in the sleeve 222 can also be used as bellows.

[0053] The transmission part 22 in this embodiment further includes an end cover 224, which is connected to and seals one end of the sleeve, and the piston 221 is inserted into the end cover 224. The end cover 224 is used to improve the air tightness of the sealed space in the sleeve 222, so that the sensor 2 can operate more stably.

[0054] The present invention also provides a preferred embodiment, in which the sensor 2 of the speed torque measuring device based on fiber grating sensing also includes a shell 24 and a sensitivity-enhancing lever 25, wherein the shell 24 is connected to the sleeve 222, and the sensitivity-enhancing lever 25 is rotatably connected to the shell 24, and the lever includes a driving end and a driven end, wherein the driving end is connected to the other end of the elastic deformation body 223, and the driven end is connected to a section of the fiber grating 23, and the other end of the fiber grating 23 is connected to the shell 24.

[0055] The sensitivity enhancement lever 25 can amplify the displacement of the transmission part 22, so that the fiber grating 23 can expand and contract more, and its signal change is more obvious. In a preferred embodiment, the sensitivity enhancement lever 25 includes a first rod body 251 and a second rod body 252. The first rod body 251 is L-shaped, and one end of the first rod body 251 is rotatably connected to the inner wall of the outer shell 24, and the middle part of the first rod body 251 is connected to the other end of the elastic deformation body 223. The other end of the first rod body 251 is rotatably connected to the middle part of the second rod body 252, and one end of the second rod body 252 is rotatably connected to the inner wall of the outer shell 24, and the other end of the second rod body 252 is connected to one end of the fiber grating 23.

[0056] In this embodiment, the location of the elastic bellows on the first rod body 251 is the driving end of the sensitivity-enhancing lever 25, and the connection between the second rod body 252 and the fiber grating 23 is the driven end of the sensitivity-enhancing lever 25. l1 and l2 are defined as the distances between the connection between the first rod body 251 and the housing 24 and the driving end, and the connection between the first rod body 251 and the second rod body 252, respectively. l3 and l4 are defined as the distances between the connection between the second rod body 252 and the housing 24 and the connection between the second rod body 252 and the first rod body 251 and the driven end, respectively. The magnification β of the sensitivity-enhancing lever 25 is:

[0057]

[0058] Furthermore, in a preferred embodiment, the speed and torque measuring device based on fiber grating sensing also includes a driving shaft 3, a driven shaft 4 and a coupling 5, wherein the driving shaft 3 and the driven shaft 4 are respectively used to connect the rotating parts to be measured, and the two follower gears are respectively fixedly mounted on the driving shaft 3 and the driven shaft 4, and the driving shaft 3 and the driven shaft 4 are connected via a coupling.

[0059] The two opposite ends of the driving shaft 3 and the driven shaft 4 can be connected to two different rotating parts through a structure such as a flange plate, so that the speed torque measurement device based on fiber grating sensing can be used to measure the speed and torque between two different rotating parts. At the same time, the coupling 5 in this embodiment adopts a flexible coupling, so that the system can withstand the movement of the movement, and in the high-speed and heavy-load power transmission, it can play a role in buffering, reducing vibration and improving the dynamic performance of the shaft system.

[0060] In a preferred embodiment, the speed torque measuring device based on fiber grating sensing also includes a detection station and a remote monitoring and information processing center, the detection station includes a fiber grating demodulator and a host computer, the remote monitoring and information processing center includes a server and a detection and diagnosis device, the fiber grating 23 is connected to the fiber grating demodulator, the fiber grating demodulator is connected to the host computer, the host computer is connected to the server through wireless communication, and the server is connected to the detection and diagnosis device. The above-mentioned devices can process signals and control other components. In practice, the fiber grating 23 can also be directly connected to other existing processing devices.

[0061] The present invention also provides a rotational speed measurement method, which uses the above-mentioned rotational speed torque measurement device based on fiber grating sensing, and obtains the wavelength signal, and the rotational speed can be directly obtained according to the relationship between the wavelength signal and the number of teeth.

[0062] Specifically, since one end of the fiber Bragg grating is fixed to the device housing with adhesive, and the other end is fixed to the sensitivity-enhancing lever and moves with it, the elongation Δl(t) of the fiber Bragg grating is equal to the displacement ω(t) of the lever output end, so the tensile strain ε of the fiber Bragg grating is:

[0063]

[0064] Where L is the effective length of the fiber Bragg grating pasting section, and ω is the deformation.

[0065] When the temperature change is very small, for a typical silica fiber, the central wavelength of the reflected light from the broadband light source when it is transmitted in the fiber Bragg grating is B . There is the following relationship with the fiber Bragg grating tensile strain ε:

[0066]

[0067] Where λ is the initial center wavelength of the reflected light of the fiber Bragg grating in its natural state.

[0068] The central wavelength λ can be obtained from the above two equations B The conversion relationship between (t) and the displacement ω(t) at the output end of the lever is:

[0069]

[0070] In the formula, L and λ are constants, λ B The relationship with ω is linear, so λ B (t) has the same signal frequency as ω(t).

[0071] The distance d(t) between the follower wheel and the end face of the permanent magnet is the same as the frequency of the magnetic force F(t) between the two, and d(t) is the same as the displacement frequency of the bellows, so λ B (t) has the same frequency as d(t).

[0072] Therefore, during detection, as the rotating part rotates, the follower wheel will also rotate, and each convex part passes the sensor, and the distance between the follower wheel and the end face of the permanent magnet changes periodically. Assuming that the follower wheel has 18 convex parts, then the wavelength signal λ finally demodulated by the fiber Bragg grating demodulator is B The frequency of (t) is 18 times the measured speed, so the speed of the rotating part can be obtained.

[0073] Further, combined with Figure 3 As shown, the present invention also provides another embodiment of a rotation speed measurement method, using the above-mentioned rotation speed torque measurement device based on fiber grating sensing, the method includes:

[0074] S301, acquiring multiple groups of wavelength signals through the multiple sensors;

[0075] S302, obtaining a plurality of rotation periods according to the wavelength signal and the number of the convex portions;

[0076] S303: Obtain the rotation speed of the rotating part according to the multiple rotation cycles.

[0077] The above steps can analyze the data acquired by multiple sensors in a unified manner, thereby obtaining more accurate data.

[0078] As a preferred embodiment, step S302 in this embodiment specifically includes:

[0079] Obtaining a zero-crossing vector group according to the moment when the falling edge of each wavelength signal crosses zero;

[0080] According to the zero-crossing vector group, a convex interval period vector group is obtained;

[0081] According to the convex portion interval periodic vector group, a plurality of rotation periods are obtained.

[0082] In the above process, the zero-crossing vector group is obtained by the time when the falling edge crosses zero. In practice, the zero-crossing vector group can also be obtained according to other rules, such as the zero-crossing time of the rising edge, etc.

[0083] As a preferred embodiment, step S303 in this embodiment specifically includes:

[0084] Optimizing the rotation period;

[0085] According to the optimized rotation period, the rotation speed of the rotating part is obtained.

[0086] In a specific embodiment, the above steps S302 to S303 can be implemented by the following method:

[0087] Assume that the number of sensors in this embodiment is 6, namely A1, A2, A3, B1, B2, B3. A1, A2, A3 are arranged around the same follower wheel, and the other sensors are arranged around another follower wheel.

[0088] For high-speed rotating follow-up, the wavelength change of the signal output by the fiber Bragg grating in the time domain is a zero-average AC signal, which is approximately sinusoidal. The negative slope "zero crossing" associated with each convex part can be processed as a logic level signal for accurate timing. When each convex part passes the sensor, the signal generates a pulse, and a logic signal is generated according to the zero crossing of the signal. At the falling edge of the signal, the timing value is obtained at each zero crossing, and the zero crossing vector group can be obtained. Each vector can be expressed as

[0089]

[0090] In the formula, It represents the kth zero-crossing time of the i-th sensor, i represents the sensor (i is A1, A2, A3...), and k represents the k-th gear (k is 1, 2, 3...).

[0091] According to the above vector group, we can get the convex interval period vector group:

[0092]

[0093] In the formula, It represents the convex interval period corresponding to the kth convex part of the i-th sensor, and the time it takes for a convex part to rotate across the sensor.

[0094] According to the above convex interval period vector group, multiple rotation periods can be obtained:

[0095]

[0096] In the formula, the rotation period represents the time for the follower wheel to rotate one circle measured by the i-th sensor, N represents the number of convex parts, z -n is the unit delay function, F 00 Referring to the above processing procedure, six rotation cycles are obtained in this embodiment.

[0097] After the rotation period is obtained, it needs to be optimized. In this embodiment, the average of six rotation periods is taken to obtain the optimized rotation period:

[0098]

[0099] In the formula, M k represents the optimized rotation period, that is, the rotation period obtained by all sensors is averaged to improve the accuracy, where Q0 represents average processing.

[0100] It is understandable that in practice, other optimization schemes can be adopted according to different situations. In addition to algorithm optimization, the transmitted signal can be optimized using relevant hardware to obtain the optimized rotation period. For example, using FIR comb filter to process the signal can remove the influence of noise and processing tolerance on the zero point. The low-pass filter F AA (Second-order Butterworth filter) is used to eliminate aliasing in the measurement data, etc.

[0101] After the optimization, the rotation cycle can be used to obtain the rotation speed of the rotating part.

[0102]

[0103] In the formula, f时钟 is the frequency of the microcontroller clock that acquires the signal, in Hz, is the shaft speed in Hz, which is the desired rotational speed of the rotating part.

[0104] Combination Figure 4 As shown, the present invention also provides a torque measurement method, using the above-mentioned speed torque measurement device based on fiber grating sensing, the method comprises:

[0105] S401, acquiring multiple groups of wavelength signals through the multiple sensors;

[0106] S402, obtaining a phase difference value according to the wavelength signal;

[0107] S403: Obtain the torque of the rotating part according to the phase difference.

[0108] As a preferred embodiment, the above step S402 specifically includes:

[0109] Obtaining a phase measurement vector group according to the moment when the falling edge of each wavelength signal passes through zero;

[0110] A phase difference value is obtained according to the phase measurement vector group.

[0111] Similar to the above-mentioned rotation speed measurement method embodiment, other strategies can be used to obtain the phase measurement vector group according to specific needs. The phase difference value obtained in this step can reflect the deflection between the two follower wheels, and then the torque of the rotating part can be obtained.

[0112] Specifically, step S403 in this embodiment includes:

[0113] Optimizing the phase difference value;

[0114] According to the optimized phase difference value, the shaft torsion is obtained;

[0115] The torque of the rotating member is obtained according to the shaft torsion.

[0116] In a specific embodiment, the above steps S402 to S403 may be implemented by the following process:

[0117] Similarly, the phase measurement vector group is obtained by the zero-crossing moment of the falling edge of the wavelength signal, and each vector can be expressed as

[0118]

[0119] In the formula, represents the kth zero-crossing time of the i-th sensor, i represents the sensor (i is A1, A2, A3...), k represents the convex interval period corresponding to the k-th convex part (k is 1, 2, 3...). Q4 represents the data processing.

[0120] Averaging each element in the above vector, we get k phase difference values ​​ab k :

[0121]

[0122] Then the above phase difference value can be optimized to obtain the optimized phase difference value R k :

[0123]

[0124] In the formula, N represents the number of convex parts, z -n is the unit delay function, F 10 Indicates the above processing process.

[0125] Similarly, other optimization strategies can be used in practice, or the signal can be optimized using hardware to obtain a more accurate value. For example, a FIR digital comb filter can be used to optimize ab k Processing is performed to remove the effects of noise and machining imperfections in the torsion calculations.

[0126] After optimizing the phase difference, the desired shaft torsion Δθ can be obtained through the optimized phase difference. k :

[0127]

[0128] The required torque T of the rotating part is obtained according to the shaft torsion:

[0129]

[0130]

[0131] In the above formula, Δθ is the degree of circumferential torsion, T is the torque, L is the axial length between each protrusion, G is the shear modulus, J is the polar moment of inertia, and K is the torsional stiffness of the shaft.

[0132] The present invention provides a speed torque measuring device and a measuring method based on fiber grating sensing. By installing a follower wheel on the rotating part to be measured, the follower wheel rotates with the rotating part. The convex part on the follower wheel drives the permanent magnet in the sensor to vibrate along the radial direction of the follower wheel. The permanent magnet is transmitted through the transmission part to cause the fiber grating to undergo periodic strain, so that the light transmitted in the fiber grating will change, and the change law can reflect the motion law of the permanent magnet, that is, the rotation of the follower wheel. By setting multiple sensors according to certain rules and obtaining wavelength signals collected by multiple sensors, the speed, torque and other information of the rotating part to be measured can be analyzed. Compared with the prior art, the present invention makes full use of the advantages of fiber grating in anti-electromagnetic interference, corrosion resistance, high temperature resistance, small size, light weight, easy distributed dynamic measurement, etc., and has a simple structure, convenient on-site installation and wiring, and most importantly, it can effectively and accurately measure the speed and torque, and has a good application prospect.

[0133] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0134] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A speed torque measurement device based on fiber grating sensing, characterized in that: include: Two follower wheels are coaxially connected to the rotating member to be tested, and the circumference of the follower wheels is evenly provided with a plurality of convex parts with magnetic force; A plurality of sensors, each two of the sensors form a group, the two sensors in each group are arranged along the axial direction of the follower wheel and correspond to two follower wheels respectively, and the plurality of groups of sensors are arranged around the follower wheel; The sensor comprises: a housing, a permanent magnet, a transmission part and a fiber Bragg grating, wherein the permanent magnet is slidably arranged on the housing, one end of the permanent magnet faces the circumference of the follower wheel, the other end of the permanent magnet, the transmission part and one end of the fiber Bragg grating are connected in sequence, and the other end of the fiber Bragg grating is connected to the housing; The transmission part includes a piston, a sleeve and an elastic deformation body. The other end of the permanent magnet is connected to the piston. The piston is inserted into one end of the sleeve. The sleeve is connected to the shell. The elastic deformation body is connected to the other end of the sleeve. The elastic deformation body, the sleeve and the piston together form a sealed space filled with inert gas. The elastic deformation body is connected to one end of the optical fiber grating.

2. The speed and torque measuring device based on fiber grating sensing according to claim 1 is characterized in that: It also includes a sensitivity enhancement lever, which is rotatably connected to the shell. The lever includes a driving end and a driven end. The driving end is connected to the other end of the elastic deformation body, the driven end is connected to a section of the fiber grating, and the other end of the fiber grating is connected to the shell.

3. The speed and torque measuring device based on fiber grating sensing according to claim 2 is characterized in that: The sensitivity enhancement lever includes a first rod body and a second rod body, the first rod body is L-shaped, one end of the first rod body is rotatably connected to the inner wall of the outer shell, the middle part of the first rod body is connected to the other end of the elastic deformation body, the other end of the first rod body is rotatably connected to the middle part of the second rod body, one end of the second rod body is rotatably connected to the inner wall of the outer shell, and the other end of the second rod body is connected to one end of the optical fiber Bragg grating.

4. A rotation speed measurement method, characterized in that: Using the speed torque measurement device based on fiber grating sensing as described in any one of claims 1 to 3, the method comprises: Acquire multiple groups of wavelength signals through the multiple sensors; Obtaining a plurality of rotation periods according to the wavelength signal and the number of the convex portions; According to the plurality of rotation cycles, the rotation speed of the rotating member is obtained.

5. The rotation speed measurement method according to claim 4, characterized in that: The step of obtaining a plurality of rotation periods according to the wavelength signal and the number of the convex portions comprises: Obtaining a zero-crossing vector group according to the moment when the falling edge of each wavelength signal crosses zero; According to the zero-crossing vector group, a convex interval period vector group is obtained; According to the convex portion interval periodic vector group, a plurality of rotation periods are obtained.

6. The rotation speed measurement method according to claim 5, characterized in that: The step of obtaining the rotation speed of the rotating member according to the plurality of rotation cycles comprises: Optimizing the rotation period; According to the optimized rotation period, the rotation speed of the rotating part is obtained.

7. A torque measurement method, characterized in that: Using the speed torque measurement device based on fiber grating sensing as described in any one of claims 1 to 3, the method comprises: Acquire multiple groups of wavelength signals through the multiple sensors; Obtaining a phase difference value according to the wavelength signal; The torque of the rotating member is obtained according to the phase difference.

8. The torque measurement method according to claim 7, characterized in that: The step of obtaining a phase difference value according to the wavelength signal comprises: Obtaining a phase measurement vector group according to the moment when the falling edge of each wavelength signal passes through zero; A phase difference value is obtained according to the phase measurement vector group.

9. The torque measurement method according to claim 8, characterized in that: The step of obtaining the torque of the rotating member according to the phase difference value comprises: Optimizing the phase difference value; According to the optimized phase difference value, the shaft torsion is obtained; The torque of the rotating member is obtained according to the shaft torsion.

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