Flexible magnetic type bimodal grinding signal monitoring device and machine tool

Abstract

The invention belongs to the technical field of grinding test, provides a magnetic bimodal flexible monitoring device for grinding heat and grinding force and a machine tool, and solves the problem that the structure of a test system needs to be changed for measuring the grinding temperature and the grinding force in the prior art, and adopts the technical scheme that an electromagnetic workbench, a flexible magnetic bimodal sensor and a signal processing device are arranged; one side of the flexible magnetic bimodal sensor is adsorbed to the electromagnetic workbench, the other side of the flexible magnetic bimodal sensor is adsorbed to a workpiece, and the flexible magnetic bimodal sensor is connected with the data processing module; the flexible magnetic dual-mode sensor comprises a grinding temperature measuring structure and a grinding force measuring structure, and the signal processing device is configured to receive change information of resistors in the grinding temperature measuring structure and the grinding temperature measuring structure when the grinding temperature or the grinding force changes; and the corresponding grinding temperature and grinding force are calculated according to the resistance change information. The structure of the device does not need to be changed, measurement precision is considered, and stable and efficient grinding temperature and grinding force detection is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of grinding testing, and particularly relates to a flexible magnetic adsorption type dual-mode grinding machining signal monitoring device and a machine tool. Background Art

[0002] The statements in this part only provide background technical information related to the present invention, and do not necessarily constitute prior art.

[0003] The grinding temperature and grinding force testing technologies are important research fields in modern mechanical manufacturing. During the grinding process, energy is mainly converted into heat, concentrated in the grinding area, resulting in an increase in grinding temperature, which affects the surface quality of the workpiece and the tool life. Research shows that there is a direct relationship between grinding force and grinding temperature, and higher grinding force is usually accompanied by higher grinding temperature. Therefore, the testing technologies for grinding temperature and grinding force are of great significance for optimizing the grinding process, improving the workpiece quality and extending the tool life. It is crucial to accurately measure and control the temperature and force during the grinding process.

[0004] Currently, the existing grinding temperature and grinding force detection system devices mainly include thermocouples, piezoelectric sensors, dynamometers, etc. The grinding temperature measurement system needs to use screws or other fixing devices to fix the thermocouple at the installation position, or needs to change the workpiece structure for installation. The thermocouple is installed in the small hole of the workpiece through brazing or other fixing methods. The installation method may involve complex structural design and component configuration, and the installation process is relatively complex; the grinding force measurement system has problems in the linear relationship of the force-strain signal, the mutual interference of the horizontal and vertical forces, and the contradiction between sensitivity and stiffness. The dynamic characteristics of the dynamometer are poor and it is easily interfered by off-axis forces, thus affecting the measurement accuracy.

[0005] Currently, the measuring device for simultaneously measuring grinding temperature and force adopts a thermocouple-force sensor combination. Its defects are that the invasive design destroys the tool / workpiece structure, the calibration and maintenance costs are high, and there is cross-interference between the temperature and force signals. When the dual-mode sensing system for simultaneously measuring temperature and force detects external physical signals, accidental signal interference or fluctuations may occur, reducing the sensor accuracy due to the distortion of the output signal, and even generating incorrect data, posing potential safety hazards. Summary of the Invention

[0006] In order to solve at least one of the above technical problems in the background art, the first aspect of the present invention provides a flexible magnetic adsorption type dual-mode grinding machining signal monitoring device, which avoids invasive damage to the workpiece structure and cross-interference of temperature and force dual-mode information, and realizes simultaneous consideration of measurement accuracy and stable and efficient detection of grinding temperature and grinding force.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A flexible magnetic adsorption type dual-mode grinding processing signal monitoring device, including a monitoring device body, an electromagnetic workbench, a flexible magnetic adsorption dual-mode sensor and a signal processing device are arranged on the monitoring device body; the flexible magnetic adsorption dual-mode sensor includes a first magnetic film, a second magnetic film, a grinding temperature measurement structure, a grinding force measurement structure and a butterfly scale-like insulating buffer layer; the magnetic poles of the first magnetic film and the second magnetic film are opposite to each other, the second magnetic film is adsorbed on the electromagnetic workbench, and the first magnetic film is adsorbed and contacts the bottom of the measured grinding workpiece; the butterfly scale-like insulating buffer layer is arranged between the grinding temperature measurement structure and the grinding force measurement structure, and the grinding temperature measurement structure and the grinding force measurement structure are connected to the signal processing device.

[0009] As an implementation manner, the grinding temperature measurement structure includes a temperature-sensitive layer, the grinding force measurement structure includes a first electrode, a piezoelectric thin film layer and a second electrode, the temperature-sensitive layer is arranged on one side of the butterfly scale-like insulating buffer layer, and the first electrode, the piezoelectric thin film layer and the second electrode are adhesively arranged on the other side of the butterfly scale-like insulating buffer layer in sequence from top to bottom.

[0010] As an implementation manner, the temperature-sensitive layer includes a temperature-sensitive material layer, an array electrode, a connection lead wire and an interface, the array electrode is arranged on the temperature-sensitive material layer, and the array electrode is connected to the interface through the connection lead wire; the interface is connected to the signal processing device; the upper surface of the piezoelectric thin film layer is coated with a first electrode, and the lower surface is coated with a second electrode, the first electrode is connected with a first wire, the second electrode is connected with a second wire, and the first wire and the second wire are connected to the signal processing device.

[0011] As an implementation manner, the internal structure of the piezoelectric thin film layer adopts a hexagonal microstructure imitating a honeycomb.

[0012] As an implementation manner, the array electrode adopts 6 rows and 4 columns of electrodes, one end of each row of electrodes is connected to a common interface, and the other end is respectively connected to the corresponding interface.

[0013] As an implementation manner, the butterfly scale-like insulating buffer layer includes a base layer, a plurality of micro-grooves are arranged on the base layer, the micro-groove structure is arranged in a grid pattern, and the surface of the base layer and the micro-grooves arranged in a grid pattern form a network-like ridge structure.

[0014] As an implementation manner, the signal processing device includes a ferromagnetic metal base plate, a data processing module, a power supply module, and a wireless communication module. The ferromagnetic metal base plate is adsorbed and fixed on the side of the electromagnetic workbench. The data processing module, the power supply module, and the wireless communication module are installed on the ferromagnetic metal base plate. The power supply module and the wireless communication module are connected to the data processing module.

[0015] As an implementation manner, the wireless communication module uses a 2.4G RF wireless radio frequency module.

[0016] As an implementation manner, the data processing module includes a preprocessing module, a decoupling module, and a fusion compensation module;

[0017] Among them, the preprocessing module is configured to: digitally filter and baseline calibrate the received original bimodal signal data;

[0018] The decoupling module is configured to: decouple the preprocessed bimodal signals in the time domain and the frequency domain respectively to obtain the decoupled temperature signal and pressure signal;

[0019] The fusion compensation module is configured to: combine the decoupled temperature signal and pressure signal to construct a temperature-force coupling matrix, establish a nonlinear influence model of temperature on pressure sensitivity based on the temperature-force coupling matrix, analyze the quantitative description of the influence of temperature change on pressure sensitivity in combination with the nonlinear influence model of temperature on pressure sensitivity, and obtain the anti-interference optimized data after multimodal fusion.

[0020] In order to solve the above problems, the second aspect of the present invention provides a flexible magnetic adsorption type bimodal grinding processing signal monitoring, which can simultaneously take into account the measurement accuracy and stably and efficiently detect the grinding temperature and grinding force.

[0021] In order to achieve the above object, the present invention adopts the following technical solutions:

[0022] A flexible magnetic adsorption type bimodal grinding processing signal monitoring includes a flexible magnetic adsorption type bimodal grinding processing signal monitoring device as described in the first aspect.

[0023] The beneficial effects of the present invention are:

[0024] 1. The grinding heat and grinding force measuring device of the magnetic adsorption dual - mode sensor of the present invention is composed of a wire - shaped induction element wrapped by two opposite - sex magnetic films through a flexible magnetic adsorption dual - mode sensor. It can tightly adsorb the bottom surface of the workpiece to be measured, and can simultaneously detect grinding temperature and grinding force, avoiding invasive damage to the workpiece structure. At the same time, an insulating buffer layer imitating butterfly scales is set between the grinding temperature measurement structure and the grinding force measurement structure to avoid cross - interference of temperature and force dual - mode information. The measured signals are transmitted to the processing system through the temperature - sensitive layer and the piezoelectric layer, taking into account the measurement accuracy and detecting grinding temperature and grinding force stably and efficiently.

[0025] 2. In response to the dual - mode signal interference or fluctuation in case of an accident, the present invention designs corresponding separation processing and anti - interference processing of dual - mode data, improving the accuracy of the final grinding force and grinding heat data.

[0026] 3. By using flexible materials to prepare the sensor, the present invention usually adopts simple and low - cost manufacturing processes, making it have advantages in large - scale production. Flexible sensors usually have low power consumption, are easy to carry and can be used for a long time.

[0027] Advantages of additional aspects of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings forming a part of this specification are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0029] Figure 1 It is a schematic diagram of the overall structure of the grinding heat and grinding force measuring device of the flexible magnetic adsorption dual - mode sensor provided in Embodiment 1 of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of the flexible magnetic adsorption dual - mode sensor provided in Embodiment 1 of the present invention;

[0031] Figure 3 It is a schematic diagram of the magnetic adsorption principle of the flexible measuring device provided in Embodiment 1 of the present invention;

[0032] Figure 4 It is a schematic diagram of the structure of the grinding temperature measurement part of the flexible sensor provided in Embodiment 1 of the present invention;

[0033] Figure 5 It is a schematic diagram of the insulating buffer layer imitating butterfly scales of the flexible sensor provided in Embodiment 1 of the present invention;

[0034] Figure 6It is the anti-interference schematic diagram of the flexible sensor imitating butterfly scales insulation buffer layer provided in Embodiment 1 of the present invention;

[0035] Figure 7 It is the structural schematic diagram of the grinding force measurement part of the flexible sensor provided in Embodiment 1 of the present invention;

[0036] Figure 8 It is the structural schematic diagram of the measuring device provided in Embodiment 1 of the present invention;

[0037] Figure 9 It is the schematic diagram of the power supply module provided in Embodiment 1 of the present invention;

[0038] Figure 10 It is the partial schematic diagram of the signal acquisition device provided in Embodiment 1 of the present invention;

[0039] Figure 11 It is the flow chart of the software anti-interference processing of dual-mode raw data provided in Embodiment 1 of the present invention;

[0040] Figure 12 It is the structural schematic diagram of the flexible magnetic dual-mode sensor provided in Embodiment 2 of the present invention;

[0041] Figure 13 It is the structural schematic diagram of the grinding heat and grinding force measurement machine tool of the flexible magnetic dual-mode sensor provided in Embodiment 3 of the present invention;

[0042] Figure 14 It is the flow chart of the grinding temperature and grinding force monitoring system provided in Embodiment 3 of the present invention;

[0043] Among them, 1. Electromagnetic workbench, 2. Flexible magnetic dual-mode sensor, 201. First magnetic film, 202. Temperature-sensitive layer, 2021. Temperature-sensitive material layer, 2022. Array electrode, 2023. Connection line, 2024. Interface, 203. Butterfly scale-like insulation buffer layer, 2031. Network-shaped ridge vein, 2032. Grid-shaped hollow, 204. First electrode, 2041. First wire, 205. Piezoelectric film layer, 206. Second electrode, 2061. Second wire, 207. Second magnetic film, 3. Flexible wire, 4. Workpiece, 5. Signal processing device, 501. Ferromagnetic metal bottom plate, 502. Data processing module, 503. Power supply module, 504. Wireless communication module, 505. Protective cover, 6. Machine tool body, 7. Column, 8. Feed shaft, 9. Grinding wheel, 10. Reflector, 11. Laser head, 12. Protective cover, 13. Handwheel, 14. Joystick, 15. Display screen, 16. Chip removal table, 17. T-shaped groove, 18. Electrical cabinet, 19. Control box. Detailed implementation manners

[0044] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0045] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0046] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0047] In the present invention, terms such as "fixed connection", "connected", "connected" should be understood in a broad sense, which may mean a fixed connection, an integral connection or a detachable connection; it may be directly connected or indirectly connected through an intermediate medium. For those related scientific research or technical personnel in the field, the specific meanings of the above terms in the present invention can be determined according to specific circumstances, and should not be construed as a limitation to the present invention.

[0048] Embodiment 1

[0049] See Figures 1-7 , this embodiment provides a magnetic adsorption type dual-mode grinding signal measuring device, including a measuring device body, an electromagnetic workbench 1, a flexible magnetic adsorption dual-mode sensor 2, a flexible wire 3 and a data processing module are arranged on the measuring device body; one side of the flexible magnetic adsorption dual-mode sensor 2 is adsorbed to the electromagnetic workbench 1, and the other side is adsorbed to the workpiece 4, and the flexible magnetic adsorption dual-mode sensor 2 and the data processing module are connected by the flexible wire 3; the flexible magnetic adsorption dual-mode sensor 2 includes a grinding temperature measurement structure and a grinding force measurement structure;

[0050] As Figure 2 shown, the flexible magnetic adsorption dual-mode sensor 2 includes a first magnetic film 201, a temperature-sensitive layer 202, a butterfly scale-like insulating buffer layer 203, a first electrode 204, a piezoelectric thin film layer 205, a second electrode 206 and a second magnetic film 207;

[0051] The magnetic poles of the first magnetic film 201 and the second magnetic film 207 are opposite to each other, and they serve as both a magnetic adsorption structure and a flexible substrate of the flexible sensor;

[0052] As Figure 2As shown, the second magnetic film 207 is adsorbed on the electromagnetic workbench 1. The temperature-sensitive layer 202, the butterfly-scale-like insulating buffer layer 203, the first electrode 204, the piezoelectric thin film layer 205, and the second electrode 206 are the main body of the sensor. The temperature-sensitive layer 202, the butterfly-scale-like insulating buffer layer 203, the first electrode 204, the piezoelectric thin film layer 205, and the second electrode 206 are adhesively bonded in sequence from top to bottom. A first magnetic film 201 is arranged above the sensor main body, and the first magnetic film 201 directly adsorbs and contacts the bottom of the workpiece to be measured and ground;

[0053] As Figure 3 shown, the adsorption principle of the electromagnetic workbench 1, the flexible magnetic adsorption dual-mode sensor 2 and the workpiece is as follows:

[0054] When the electromagnetic workbench 1 operates, the magnetic poles of the electromagnetic workbench 1 and the second magnetic film 206 of the flexible magnetic adsorption dual-mode sensor 2 attract each other with opposite phases, and strongly adsorb the ferromagnetic workpiece 4. The first magnetic film 201 has the same direction as the magnetic poles of the electromagnetic workbench 1, attracts each other with opposite phases with the magnetic poles of the second magnetic film 207, and attracts the ferromagnetic workpiece 4. Thus, the adsorption and fixation of the electromagnetic workbench 1, the flexible magnetic adsorption dual-mode sensor 2 and the workpiece 4 are completed.

[0055] Furthermore, the temperature-sensitive layer 202, as the main body for the flexible magnetic adsorption dual-mode sensor to measure the grinding temperature, is made of a conductive material and is used to sense the change of the grinding temperature.

[0056] As Figure 4 shown, the temperature-sensitive layer 202 includes a temperature-sensitive material layer 2021, an array electrode 2022, a connection wire 2023, and an interface 2024. The array electrode 2022 is arranged on the temperature-sensitive material layer 2021, and the array electrode 2022 is connected to the interface 2024 through the connection wire 2023; the interface 2024 is connected to the data processing module;

[0057] When the temperature changes, the resistance of the array electrode 2022 will change, and the temperature information is converted into an electrical signal through the connection wire 2023 by the electrode interface 2024 and input into the data processing module;

[0058] In this embodiment, the array electrode adopts a 6-row and 4-column electrode. One end of each row of electrodes is connected to a common interface, and the other end is respectively connected to the corresponding interface, that is, the electrodes in the first row are connected to the second interface, the electrodes in the third row are connected to the third interface, and so on. The other end of each row of electrodes in the array electrode is connected to the corresponding interface;

[0059] Through the multi-node distributed layout of the array electrode, the refined measurement of the temperature field can be realized. The multi-channel signals of the subsequent resistance array can separate the coupling effect of temperature and mechanical deformation through the differential algorithm, and realize the suppression of temperature-strain cross-interference.

[0060] Furthermore, silver paste is used at both ends of the interface 2024 as a signal output terminal, forming a flexible resistive temperature sensor as the main body for measuring the grinding temperature;

[0061] As Figure 5 shown, the butterfly-scale-like insulating buffer layer 203 includes a network-shaped ridge vein 2031 and a grid-shaped hollow 2032. The model of this structure imitates the microstructure of the tiny scales of a butterfly wing. The grid-shaped hollows 2032 distributed on the surface of the butterfly-scale-like insulating buffer layer 203 imitate the micro-grooves and bulges to form an elastic support network-shaped ridge vein 2031, which can absorb vibration energy. Imitating the hollow microcavity structure of the tiny scales of a butterfly, there is a grid-shaped hollow 2032 structure inside the butterfly-scale-like insulating buffer layer 203. Utilizing the low thermal conductivity characteristic of air to slow down heat transfer, and at the same time assisting heat dissipation through the microcirculation of the internal air flow. The above-mentioned elastic support network-shaped ridge vein 2031 of the butterfly-scale-like insulating buffer layer 203 mainly functions to buffer and disperse concentrated stress, and the structure of the grid-shaped hollow 2032 mainly reduces the physical signal influence of the grinding heat on the following grinding force sensor part.

[0062] As Figure 6 shown, the anti-interference principle of the flexible sensor butterfly-scale-like insulating buffer layer mainly changes the heat conduction path and local stress distribution through the grid pit structure, thereby suppressing the mutual interference between temperature and force signals.

[0063] Analyzing the heat conduction path from a thermal perspective, the grid pit structure reduces the heat conduction efficiency through periodic voids, forming a thermal resistance barrier. According to Fourier's law of heat conduction, the heat flux density is:

[0064]

[0065] where: q is the heat flux density (the heat conduction rate per unit area), unit: W / m 2 , k is the thermal conductivity of the material (an inherent physical property), unit: W / (m·K), is the temperature gradient, the direction points to the direction of increasing temperature, and the negative sign indicates that heat flows from high temperature to low temperature.

[0066] When there are pores, cracks or other non-thermal conduction regions in the material, the actual cross-sectional area participating in heat conduction decreases. The total cross-sectional area is: A total , the void area is: A void , the actual heat conduction area is: A e ff = A total -A void .

[0067] At this time, the total heat conduction ability of the material is weakened due to the reduction of the effective area. According to Fourier's law, the total heat flow Q can be expressed as:

[0068]

[0069] If the effective thermal conductivity k is defined eff , such that it satisfies the total heat flux expression:

[0070]

[0071] By combining equations (2) and (3), the effective thermal conductivity k of the pit region can be obtained eff as:

[0072]

[0073] where A void / A total is the proportion of the pit void area (A void void area, A total total cross-sectional area).

[0074] Conclusion: The larger the proportion of pit voids, the more tortuous the heat conduction path (k eff is smaller), and the heat flux is restricted to the solid regions between the pits.

[0075] Analyzing the local stress distribution from a mechanical perspective, the geometric mutation (pit edge) of the grid pit structure will cause local stress concentration, enhancing the sensitivity of the force signal. According to elasticity theory, the stress concentration factor K t is defined as:

[0076]

[0077] where: σ nom = F / A nom is the nominal stress (F is the external force, A nom is the cross-sectional area without pits); σ max is the maximum actual stress at the pit edge.

[0078] For the geometrically discontinuous region (approximated as a semi-elliptical notch) at the pit edge, elasticity theory analysis shows that the stress concentration factor is related to the notch geometric parameters. Taking the semi-elliptical notch as an example, its K t can be expressed as:

[0079]

[0080] In the formula, a is the notch depth and b is the radius of curvature. By analogy to the grid pit structure, the pit depth h corresponds to a and the edge radius of curvature r corresponds to b, thus deriving the stress concentration factor formula for the grid pit structure:

[0081]

[0082] Among them, K t is the stress concentration factor, h is the depth of the pit, and r is the edge curvature radius.

[0083] Conclusion: The deeper the pit (the larger h) or the sharper it is (the smaller r), the t larger K is, and the higher the force signal sensitivity is.

[0084] The grid pit structure enhances the force signal sensitivity through the stress concentration factor formula (7) and suppresses heat diffusion through the effective thermal conductivity formula (4) k eff = k(1 - A void / A total ), achieving physical separation of the temperature and force signals of the dual-mode flexible sensor.

[0085] As Figure 7 shown, a first electrode 204 is coated on the upper surface of the flexible piezoelectric film layer 205, and a second electrode 206 is coated on the lower surface. The first electrode 204 is connected to a first wire 2041, and the second electrode 206 is connected to a second wire 2061. The first wire 2041 and the second wire 2061 are connected to the data processing module. After being externally ground and excited, the flexible piezoelectric sensor body generates electrical signals on the first electrode 204 and the second electrode 206 and outputs them to the data processing module through the welded first wire 2041 and second wire 2061. Among them, the internal structure of the piezoelectric film layer 205 imitates the hexagonal microstructure of a honeycomb, enabling air circulation inside the flexible piezoelectric sensor and reducing the influence of temperature on the acquisition of the physical signal of the grinding force.

[0086] Its working principle relies on the piezoelectric effect: When a material is deformed under an external force, charge separation occurs inside it, and the formed positive and negative charges accumulate on two opposite surfaces of the piezoelectric film layer 205 respectively. This charge separation process generates a voltage inside the material, and by measuring the voltage changes between the first electrode 204 and the second electrode 206, the magnitude of the grinding force can be reflected.

[0087] As Figure 8 shown, a signal processing device 5 is installed on the side of the measuring device body. The signal processing device 5 includes a ferromagnetic metal base plate 501, a data processing module 502, a power supply module 503, a wireless communication module 504, and a protective cover 505;

[0088] Among them, the ferromagnetic metal base plate 501 is adsorbed and fixed on the side of the electromagnetic workbench. The data processing module 502, the power supply module 503, and the wireless communication module 504 are installed on the ferromagnetic metal base plate 501. The power supply module 503 and the wireless communication module 504 are connected to the data processing module 502. The protective cover 505 protects all the data processing module 502, the power supply module 503, and the wireless communication module 504.

[0089] As Figure 9 is the schematic diagram of the power supply module 503, which can reduce the 5V voltage to 3.3V for powering the microprocessor. The SPX3819M5 forward voltage regulator is used, which has a low dropout voltage and a low-noise output, including battery reverse protection, current limiting, and thermal shutdown, and has a very low output temperature coefficient, which can be used as a low-power voltage reference to ensure the stability of the power supply circuit of the sensing system in a high-temperature test environment. In this embodiment, the main body of the wireless communication module uses 2.4G RF wireless frequency, and by using the frequency band from 2.4GHz to 2.4835GHz, the data signal is encoded and transmitted wirelessly to transmit data to the receiving device at the computer PC end.

[0090] Since both the pressure sensor part and the temperature sensor part of the flexible pressure-temperature bimodal sensor output resistance signals, the change range of the output resistance of the grinding force measurement structure is 500Ω - 5MΩ, and the resistance change of the grinding temperature measurement structure is 8kΩ - 11kΩ.

[0091] In this embodiment, the data processing module includes a signal amplification circuit. Preferably, the RS8558 micro high-precision operational amplifier is used to amplify the signal. This chip contains two operational amplifiers, one for amplifying the pressure sensing signal and one for amplifying the temperature sensing signal. This operational amplifier uses automatic zeroing technology and hardly changes with time and temperature, and has ultra-low noise, offset, and power. As Figure 10 shown, the flexible magnetic adsorption bimodal sensor includes two parts: temperature acquisition and force acquisition for grinding. When excited by the workpiece to be ground, it converts the excitation into an electrical parameter signal (voltage or resistance). When the temperature changes, the resistance of the grinding temperature acquisition part will change, thus converting the temperature information into an electrical signal; when the grinding force changes, the material of the grinding force acquisition part deforms under the action of external force, and a voltage change occurs inside the material to reflect the magnitude of the grinding force.

[0092] As Figure 11 shown, the data processing module 502 includes a signal receiving module, a signal preprocessing module, a signal decoupling module, a fusion compensation module, and a post-processing module;

[0093] The signal receiving module is configured to: receive the original bimodal signal (unprocessed electrical signal), including temperature sensor data and force sensor data;

[0094] The signal preprocessing module is configured to: perform digital filtering and baseline calibration on the acquired original bimodal signal;

[0095] Among them, digital filtering includes filtering the signals obtained from the temperature signal channel and the force signal channel respectively; specifically, the temperature signal channel uses band-pass filtering to retain the effective temperature change characteristics and suppress the environmental temperature drift and power frequency interference; the pressure signal channel uses a low-pass filter to eliminate high-frequency noise. The filtered signals enter the baseline calibration stage, and the temperature signal channel and the pressure signal channel interact in the baseline calibration stage.

[0096] Among them, baseline calibration includes dynamic temperature drift compensation for real-time updating of the baseline value and mechanical stress residue elimination for recording and compensating the zero offset of the pressure sensor.

[0097] Specifically, in the temperature-compensated force signal, the band-pass filtering result of the temperature signal channel is used to dynamically correct the temperature drift offset of the force signal through a quadratic polynomial model; in the stress residue feedback, the filtered data of the force signal channel is used to judge the mechanical stress residue state. When no external force is detected, the residual stress value is fed back to the temperature channel to avoid interference with temperature measurement during the stress release process. The stress residue error is further deducted from the temperature-compensated signal, and finally a doubly calibrated baseline signal is output.

[0098] The signal decoupling module is configured to: perform time-domain and frequency-domain decoupling on the preprocessed standardized dual-channel digital signals (filtered signals and dynamic baseline calibration data) to obtain decoupled independent physical quantity signals, namely temperature components and pressure components;

[0099] Specifically, in the time domain, the temperature signal is used as the reference noise input, and the filter weights are dynamically adjusted through the LMS algorithm to subtract the pseudo-stress component caused by the change of the temperature coupling component from the force signal; in the frequency domain, the low-frequency band of the force signal is extracted, the high-frequency noise is discarded, the full frequency band of the temperature signal is extracted, and the full frequency band characteristics are retained to capture rapid temperature changes;

[0100] The fusion compensation module is configured to: construct a temperature-force coupling matrix by combining the decoupled independent physical signals, based on the temperature-force coupling matrix, establish a non-linear influence model of temperature on pressure sensitivity, and obtain anti-interference optimized data after multi-modal fusion through quantitative description of the influence of temperature change on pressure sensitivity;

[0101] Specifically, it includes:

[0102] Considering that the effects of temperature and force on the system are mutually coupled, a matrix that can reflect the effects of these two factors simultaneously needs to be constructed. Assuming that the system has multiple temperature nodes and force nodes, the temperature-force coupling matrix can be expressed as:

[0103]

[0104] Among them, c ijIt represents the coupling coefficient between the i-th temperature node and the j-th force node.

[0105] Assume that the relationship between the pressure sensitivity S and the temperature T and force F is non-linear. A polynomial form can be used to describe this relationship:

[0106] S(T,F) = a0 + a1T + a2F + a3T 2 + a4TF + a5F 2 +... (9),

[0107] where a0, a1, a2... are undetermined coefficients.

[0108] Through the temperature-force coupling matrix C in formula (8), the effects of temperature and force can be combined to obtain the non-linear expression of the pressure sensitivity:

[0109] S = C·X (10),

[0110] where X is the vector of temperature and force, and C is the temperature-force coupling matrix. Collect the pressure sensitivity data under different temperature and force conditions. For example, at different temperatures T1, T2,..., T n and forces F1, F2,..., F m the measured pressure sensitivities are S 11 , S 12 ,..., S mn .

[0111] Using the collected data, through the least squares method or other fitting methods, determine the undetermined coefficients a0, a1, a2... in the non-linear model. For example, for the non-linear model in polynomial form, substitute the data into formula (9) to get:

[0112]

[0113] By solving the above system of equations (11), obtain the values of the undetermined coefficients.

[0114] By calculating the pressure sensitivity and taking the partial derivatives of formula (9) with respect to the temperature T and force F, analyze the influence degree of the temperature and force changes on the pressure sensitivity:

[0115]

[0116] By analyzing the signs and magnitudes of the above partial derivatives (12), (13), the positive and negative effects of temperature and force on the pressure sensitivity and the strength of the effects can be judged.

[0117] Through the parameter fitting (11) process, the undetermined coefficients a0, a1, a2... in the nonlinear model are obtained. These coefficients reflect the quantitative influence of temperature and force on the pressure sensitivity. Through this model, the specific influence law of temperature change on pressure measurement can be quantified, thus realizing more accurate pressure measurement. In the fusion compensation module, an SVM classifier can also be used to identify abnormal coupling signals, such as spikes generated by poor contact.

[0118] The post-processing module is configured to: input the anti-interference optimized data after the above-mentioned multi-modal fusion into the post-processing module for data processing and optimization. Data standardization: Convert the force / temperature data into a standardized format with zero mean and unit variance for cross-modal fusion (Z-Score normalization). Spatiotemporal alignment: Perform spline interpolation on the asynchronously collected data to achieve millisecond-level time alignment (timestamp synchronization), and convert the local measurement values into a global thermal-force distribution map according to the sensor array positioning (spatiotemporal mapping). Anomaly detection: In the sliding window analysis, calculate the variance to detect mutation signals.

[0119] Output and apply the fully processed data on the PC side to generate a visualization interface of a dynamic thermal map and a pressure distribution cloud map; input the processed data into the controller for control decision-making; upload it to the cloud database for storage.

[0120] Embodiment 2

[0121] This embodiment provides a flexible measurement device for a vertical five-axis linkage grinding machine, which retains the grinding heat and grinding force flexible magnetic adsorption dual-modal sensor acquisition module, data processing module, wireless communication module, and power supply module on the basis of Embodiment 1. Among them, the specific functions of the grinding heat and grinding force flexible magnetic adsorption dual-modal sensor acquisition module, wireless communication module, and power supply module are all similar to those in Embodiment 1 and will not be elaborated here. Different from Embodiment 1, this flexible magnetic adsorption dual-modal sensor measurement device is implemented in another grinding machine tool structure, and the shapes of the corresponding flexible magnetic adsorption dual-modal sensors are different.

[0122] As Figure 12 shown, the flexible magnetic adsorption dual-modal sensor includes a first magnetic film, a temperature-sensitive layer, an insulating layer, a first electrode, a piezoelectric thin film layer, a second electrode, and a second magnetic film;

[0123] The magnetic poles of the first magnetic film and the second magnetic film are of opposite polarity. The flexible substrate serves as both a magnetic absorption structure and a flexible sensor. The temperature-sensitive layer is the main body of the flexible magnetic absorption dual-mode sensor for measuring the grinding temperature and is used to sense the change in grinding temperature. The insulating layer is used to buffer and disperse the concentrated stress and isolate the interference of the upper part temperature on the lower part force measurement. The combination of the first electrode, the piezoelectric thin film layer, and the second electrode is the main body of the flexible magnetic absorption dual-mode sensor for measuring the grinding force. Its working principle relies on the piezoelectric effect. By measuring the voltage change between the first electrode and the second electrode on two surfaces, the magnitude of the grinding force is reflected.

[0124] The specific difference from Embodiment 1 is as follows:

[0125] In Embodiment 1, the electrodes of the temperature-sensitive layer adopt a matrix arrangement structure, and the first electrode and the second electrode of the piezoelectric thin film layer adopt a cross arrangement.

[0126] In Embodiment 2, the electrodes of the temperature-sensitive layer adopt a circumferential uniform layout, and the first electrode and the second electrode of the piezoelectric thin film layer adopt a circumferential cross arrangement.

[0127] Embodiment 3

[0128] As Figure 13 shown, this embodiment provides a flexible magnetic absorption dual-mode grinding signal monitoring machine tool, including a machine tool body 6. The electromagnetic workbench on the machine tool body 6 is fixed with the flexible magnetic absorption dual-mode grinding signal monitoring device as described in Embodiment 1 or Embodiment 2.

[0129] Furthermore, the machine tool further includes a column 7, a feed shaft 8, a grinding wheel 9, a reflector 10, and a laser head 11. The feed shaft 8 is installed on the column 7. The grinding wheel 9 is installed on the feed shaft 8 inside the column 7. The laser head 11 is installed above the feed shaft 8, and the reflector 10 is installed on the machine tool body 6 below the laser head 11. During the grinding process, the laser head 11 reflects the laser to the grinding area through the cooperation of the reflector 10, and the laser-assisted grinding wheel 9 grinds the workpiece. Further, there is a protective cover 12 around the electromagnetic workbench.

[0130] Furthermore, the machine tool further includes a control box 19 and a handwheel 13. A lead screw nut transmission mechanism is provided inside the control box 19. A lifting lead screw is arranged inside the column 7. The lead screw nut transmission mechanism is connected to the lifting lead screw. By driving the lead screw nut transmission mechanism and the lifting lead screw through the handwheel 13, the grinding wheel 9 is driven to slide longitudinally up and down along the guide rail on the column 7, so that the grinding wheel 9 grinds the workpiece.

[0131] Furthermore, the machine tool further includes a joystick 14. A lead screw connecting piece is arranged on the electromagnetic workbench. The joystick 14 is connected to the lead screw to realize the horizontal reciprocating movement of the machine tool workbench in the transverse direction.

[0132] Further, the machine tool further includes a display screen 15, and all grinding processes and grinding parameters are displayed on the display screen 15; further, the machine tool further includes a chip removal table 16 and a T-slot 17, and the chip removal table 16 is used to timely discharge the metal chips and grinding fluid generated during the grinding process on the grinding table through the T-slot 17 to keep the working environment clean and safe.

[0133] Further, the machine tool further includes an electrical cabinet 18, and the electrical cabinet 18 is used to provide power supply and electrical control for the entire surface grinder.

[0134] Figure 14 It is a flow chart of the grinding temperature and grinding force monitoring system, including the following steps:

[0135] 1. Start: The starting point of the flow chart, indicating the start of the operation of the sensor measuring the grinding temperature and grinding force system.

[0136] 2. Start the machine tool: Turn on the power supply of the machine tool and prepare for the grinding operation.

[0137] 3. Initialize the sensor monitoring system: Ensure that the sensors are working properly and are connected to the data acquisition system.

[0138] 4. Set the grinding parameter thresholds: Set reasonable grinding temperature and grinding force thresholds according to the workpiece material, grinding process requirements, etc.

[0139] 5. Turn on the cooling system: Provide necessary cooling to prevent the temperature from being too high during the grinding process.

[0140] 6. Synchronous data acquisition: The temperature and force data are synchronously acquired, usually through a data acquisition system, to ensure the time consistency of the data.

[0141] 7. Grinding temperature signal acquisition / grinding force signal acquisition: During the grinding process of the grinding part, the grinding temperature signals and grinding force signals at regular intervals per unit time are acquired. The grinding temperature signals acquired per unit time form a temperature signal set, and the grinding force signals acquired per unit time form a force signal set.

[0142] 8. Identify the grinding temperature in the measured area / identify the measured grinding force: After the acquisition per unit time is completed, the PC-side system identifies, processes, and calculates the grinding temperature and grinding force in the measured area.

[0143] 9. Data analysis and judgment: Compare the grinding contact area temperature with the temperature threshold, and compare the grinding force of the grinding part with the grinding force threshold.

[0144] 10. Determine whether the grinding state is stable: When the temperature in the grinding contact area is less than the temperature threshold and the grinding force of the grinding piece is less than the grinding force threshold, it is determined that the grinding piece is in a stable grinding state. Subsequently, repeat steps 6-8; when the temperature in the grinding contact area is greater than or equal to the temperature threshold, or the grinding force of the grinding piece is greater than or equal to the grinding force threshold, it is determined that the grinding piece is in a worn state, and continue to the next step.

[0145] 11. Adjust the grinding parameters and the grinding process system: Take necessary measures according to the inspection results, adjust the grinding parameters, the grinding process system, the cooling system, replace the grinding tool or perform other necessary repairs.

[0146] 12. Confirm that the problem is solved: Ensure that the measures taken are effective. If the problem has been solved, then repeat steps 6-11; if the problem cannot be solved immediately, then end the processing.

[0147] 13. Stop grinding: When the grinding process ends, the system can be shut down or reset for the next use.

[0148] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A flexible magnetic dual-mode grinding signal monitoring device, characterized in that: It comprises a monitoring device body, on which an electromagnetic workbench, a flexible magnetic dual-mode sensor and a signal processing device are arranged; the flexible magnetic dual-mode sensor comprises a first magnetic film, a second magnetic film, a grinding temperature measurement structure, a grinding force measurement structure and an imitation butterfly scale insulating buffer layer; the magnetic poles of the first magnetic film and the second magnetic film are mutually anisotropic, the second magnetic film is adsorbed on the electromagnetic workbench, and the first magnetic film is adsorbed and contacts the bottom of the measured grinding workpiece; the imitation butterfly scale insulating buffer layer is arranged between the grinding temperature measurement structure and the grinding force measurement structure, and the grinding temperature measurement structure and the grinding force measurement structure are connected to the signal processing device.

2. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 1, characterized in that: The grinding temperature measurement structure includes a temperature-sensitive layer, and the grinding force measurement structure includes a first electrode, a piezoelectric film layer and a second electrode. The temperature-sensitive layer is arranged on one side of the butterfly scale-like insulating buffer layer, and the first electrode, the piezoelectric film layer and the second electrode are bonded and arranged on the other side of the butterfly scale-like insulating buffer layer in sequence from top to bottom.

3. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 2, characterized in that: The temperature-sensitive layer includes a temperature-sensitive material layer, an array electrode, a connecting wire circuit and an interface. The array electrode is arranged on the temperature-sensitive material layer, and the array electrode is connected to the interface through the connecting wire circuit; the interface is connected to a signal processing device; the upper surface of the piezoelectric film layer is coated with a first electrode, and the lower surface is coated with a second electrode, the first electrode is connected to a first wire, the second electrode is connected to a second wire, and the first wire and the second wire are connected to the signal processing device.

4. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 2, characterized in that: The internal structure of the piezoelectric film layer adopts a hexagonal microstructure that imitates a honeycomb.

5. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 3, characterized in that: The array electrode adopts 6 rows and 4 columns of electrodes, one end of each row of electrodes is connected to a common interface, and the other end is connected to the corresponding interface.

6. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 1, characterized in that: The butterfly scale-like insulating buffer layer comprises a base layer, a plurality of micro grooves are arranged on the base layer, the micro groove structure is arranged in a grid shape, and the surface of the base layer and the micro grooves arranged in a grid shape form a network-like ridge structure.

7. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 1, characterized in that: The signal processing device includes a ferromagnetic metal base plate, a data processing module, a power module and a wireless communication module. The ferromagnetic metal base plate is adsorbed and fixed on the side of the electromagnetic workbench. The data processing module, the power module and the wireless communication module are installed on the ferromagnetic metal base plate. The power module and the wireless communication module are connected to the data processing module.

8. A flexible magnetic dual-mode grinding signal monitoring device as claimed in claim 7, characterized in that: The wireless communication module adopts a 2.4G RF wireless frequency module.

9. The flexible magnetic dual-mode grinding signal monitoring device according to claim 1, characterized in that: The data processing module includes a preprocessing module, a decoupling module and a fusion compensation module; Wherein, the preprocessing module is configured to: digitally filter and baseline calibrate the received original dual-modal signal data; The decoupling module is configured to: decouple the preprocessed dual-modal signal in the time domain and the frequency domain respectively to obtain a decoupled temperature signal and a pressure signal; The fusion compensation module is configured to: construct a temperature-force coupling matrix by combining the decoupled temperature signal and pressure signal, establish a nonlinear influence model of temperature on pressure sensitivity based on the temperature-force coupling matrix, analyze the quantitative description of the effect of temperature change on pressure sensitivity by combining the nonlinear influence model of temperature on pressure sensitivity, and obtain anti-interference optimization data after multimodal fusion.

10. A flexible magnetic dual-mode grinding signal monitoring machine tool, characterized in that: It comprises a flexible magnetic dual-mode grinding processing signal monitoring device as described in any one of claims 1-9.

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