Three-dimensional pulse sensor and acquisition device thereof

Abstract

The invention belongs to the technical field of electronic pulse feeling, and provides a three-dimensional pulse sensor and an acquisition device thereof. The sensor is composed of a flexible substrate and a hemispherical silica gel probe, a 3 * 3 array pressure sensor is printed on the substrate, a photoelectric volume sensor is embedded in the probe, and the flexible probe is in one-to-one correspondence with a pressure sensing area. The acquisition device comprises a conditioning conversion device and a three-dimensional pulse processing device, an ADC is controlled by an FPGA to acquire 9 paths of pressure and 9 paths of photoelectric signals, spline interpolation fitting of adjacent channels is carried out on array signals at each moment, the signals are arranged according to a time sequence, and photoelectric three-dimensional pulse signals and pressure three-dimensional pulse signals are obtained. According to the device, the three-dimensional pulse sensor is adopted, pulse signals can be collected in an omnibearing and multi-level mode, loss of data feature points is effectively reduced, the three-dimensional pulse signals meet development requirements, and the accuracy of model training and classification can be greatly improved no matter a traditional method or an artificial intelligence method is adopted.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic pulse diagnosis, and in particular to a traditional Chinese medicine pulse condition integrating photoelectricity and pressure. Background Art

[0002] Pulse diagnosis is one of the most distinctive and widely used diagnostic methods in traditional Chinese medicine. After thousands of years of accumulation of clinical practice experience, it plays an important guiding role in TCM syndrome differentiation and treatment. However, due to various historical and social factors, TCM pulse diagnosis has not been able to fully utilize modern science. Although its connotation is reasonable and its experience is rich, it still remains in the ancient form and method, resulting in limited application and development. As a subjective empirical science, traditional Chinese medicine is increasingly challenged by Western medicine. In order to solve this problem, it is urgent to eliminate the subjective factors in traditional pulse diagnosis, get rid of the qualitative diagnosis method that relies solely on personal experience through standardized and objective pulse signal acquisition and quantitative analysis.

[0003] Over the years, many researchers have made unremitting efforts in the objectification of pulse diagnosis. The key to the objectification of pulse diagnosis in traditional Chinese medicine is the acquisition of high-quality pulse signals. With the continuous advancement of sensor technology, more and more pulse sensors have been designed. The existing traditional Chinese medicine pulse meters or pulse sensors mainly use pressure sensors. Through the comparative study of existing pulse sensors, some very critical problems that need to be solved urgently are found: First, the traditional single sensor cannot replace the fingertip perception process, which will lead to the loss of pulse signals, resulting in poor training of the later neural network model and inaccurate classification. Second, there are also many photoelectric capacitance sensors to obtain pulses. Photoelectric capacitance sensors have high resolution and high sensitivity, but because photoelectric capacitance sensors cannot obtain information such as "sinking and floating" and "virtual and real" of pulses, they also have great limitations. Therefore, in order to collect pulse signals in an all-round and multi-level manner and reduce the loss of pulse signal feature points, a three-dimensional pulse sensor is designed to collect pulse signals. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the problems that the pulse signals collected by the existing pulse acquisition devices are of a single type, the characteristic points of the pulse signals are lost, and the accuracy of locating the key parts of the pulse is low, the present invention provides a three-dimensional pulse sensor and its acquisition device. The designed three-dimensional pulse acquisition device can collect three-dimensional pulse signals in an all-round and multi-level manner, solving the problems raised in the above background.

[0006] (II) Technical solution

[0007] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0008] A three-dimensional pulse sensor, the three-dimensional pulse sensor comprising a flexible substrate and a flexible probe;

[0009] A 3×3 array pressure sensor is printed on the flexible substrate, and the 3×3 array pressure sensor includes nine pressure sensing areas, which facilitates the positioning of the veins;

[0010] The flexible probe is composed of a hemispherical silicone structure and a photoelectric capacitance sensor, the convex surface of the hemispherical silicone structure contacts the skin, the photoelectric capacitance sensor is embedded in the convex surface, and the other side of the hemispherical silicone structure is a plane and is bonded to the pressure sensing area on the flexible substrate;

[0011] The nine flexible probes correspond to the nine pressure sensing areas on the flexible substrate and cover the key pulse area of ​​the wrist of the measured person.

[0012] Furthermore, the size of the pressure sensing area is 3.5×3.5 mm, the interval between two adjacent pressure sensing areas is 0.5 mm, the diameter of the hemispherical silicone structure is 3.5 mm, and the size of the three-dimensional pulse sensor is 14×14×4 mm.

[0013] Furthermore, the array pressure sensor is a piezoelectric film sensor, and the photoelectric capacitance sensor is composed of three 530nm green LEDs, one 660nm red LED, one 950nm infrared LED, a photodetector and two light baffles.

[0014] A three-dimensional pulse acquisition device, characterized in that the three-dimensional pulse acquisition device also includes a conditioning conversion device and a three-dimensional pulse processing device;

[0015] The conditioning conversion device includes a conditioning circuit and an analog-to-digital conversion circuit. The conditioning circuit pre-processes the initial pressure pulse signal and the photoplethysmography signal, and transmits the processed pressure pulse signal and the photoplethysmography signal to the digital-to-analog conversion circuit. The digital-to-analog conversion circuit converts the analog signal preliminarily processed by the conditioning circuit into a digital signal.

[0016] The three-dimensional pulse processing device is used for fitting the three-dimensional pulse signal, displaying the three-dimensional pulse waveform in real time, and storing the three-dimensional pulse signal data;

[0017] The three-dimensional pulse acquisition device is applied to the three-dimensional pulse sensor as claimed in any one of claims 1 to 3.

[0018] Furthermore, the number of the conditioning circuits is the same as that of the sensors, and each conditioning circuit is composed of a primary amplification circuit, a zero adjustment circuit, an industrial frequency limiting circuit, a bandpass filter circuit and a secondary amplification circuit, and sends the processed signal to the digital-to-analog conversion circuit.

[0019] Furthermore, the digital-to-analog conversion circuit includes an FPGA and two 10-channel ADC chips. The FPGA controls the two 10-channel ADC chips to collect 9-channel pressure analog signals and 9-channel photoelectric analog signals from the three-dimensional pulse sensor and convert them into 18-channel digital signals. At the same time, the FPGA is used to perform synchronous processing of the 18-channel digital signals, including FIFO data buffer and serial port transmission to the three-dimensional pulse processing device.

[0020] Furthermore, the three-dimensional pulse processing device includes three-dimensional pulse signal fitting and data display memory. The three-dimensional pulse signal fitting includes two steps. The first step is to perform spline interpolation fitting on the array signal perpendicular to the wrist direction at the same time. The second step is to sort the fitted curves in time sequence. The data display memory displays the pressure three-dimensional pulse signal and the photoelectric three-dimensional pulse signal on the host computer and saves them.

[0021] (III) Beneficial effects

[0022] Compared with the prior art, the present invention provides a three-dimensional pulse sensor and a collection device thereof, which have the following beneficial effects:

[0023] The present invention adopts a three-dimensional pulse sensor to simultaneously collect 9 pressure pulse signals and 9 photoelectric volume accumulation signals of a pulse area, thereby reducing the loss of pulse signal feature points, improving the accuracy of locating key pulse parts, and can collect pulse signals in an all-round and multi-level manner. Regardless of whether traditional methods or artificial intelligence methods are used, the accuracy of model training and classification can be greatly improved.

[0024] In traditional pulse sensors, the piezoelectric film is in direct contact with human skin, which easily introduces a large number of external interference signals. In addition, due to the shaking of the human body, multiple points of force are applied, making it difficult for the piezoelectric film to generate a stable electrical signal, thereby affecting the measurement precision and accuracy. The three-dimensional pulse sensor proposed in the present invention can effectively achieve signal isolation and focusing by adding a hemispherical silicone probe to the sensor, while increasing the contact pressure between the raised part and the skin, ensuring precise positioning and stable pressure during the test, thereby significantly improving the reliability and accuracy of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0026] Figure 1 is a schematic diagram of the structure of a three-dimensional pulse sensor according to an embodiment of the present invention;

[0027] Figure 2 is a structural block diagram of a three-dimensional pulse acquisition device according to an embodiment of the present invention;

[0028] Figure 3 is a principle block diagram of a conditioning circuit according to an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of a first-stage amplifier circuit according to an embodiment of the present invention;

[0030] Figure 5 is a schematic diagram of a zero adjustment circuit according to an embodiment of the present invention;

[0031] Figure 6 is a schematic diagram of a power frequency limiting circuit according to an embodiment of the present invention;

[0032] Figure 7 is a schematic diagram of a bandpass filter circuit according to an embodiment of the present invention;

[0033] Figure 8 is a schematic diagram of a secondary amplifier circuit according to an embodiment of the present invention;

[0034] Fig. 9 It is a principle block diagram of digital-to-analog conversion according to an embodiment of the present invention.

[0035] Description of reference numerals:

[0036] 00, three-dimensional pulse sensor; 10, flexible substrate; 20, flexible probe; 30, conditioning conversion device; 40, three-dimensional pulse processing device; 41, host computer;

[0037] 11. Array pressure sensor; 111. Pressure sensing area; 112. Polyester film; 113. Highly conductive material; 114. Nano-scale pressure-sensitive material; 115. Top layer; 116. Bottom layer;

[0038] 21. Hemispherical silicone structure; 22. Photoelectric capacitance sensor; 221. 530nm green LED; 222. 660nm red LED; 223. 950nm infrared LED; 224. Photodetector; 225. Light baffle;

[0039] 31. Conditioning circuit; 311. Primary amplifier circuit; 312. Zero adjustment circuit; 313. Power frequency limiting circuit; 314. Bandpass filter circuit; 3141. High-pass filter; 3142. Low-pass filter; 315. Secondary amplifier circuit;

[0040] 32. Digital-to-analog conversion circuit; 321. FPGA; 322. ADC chip; 323. FIFO data buffer; 324. Serial port transmission. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example:

[0043] Please refer to Figure 1 , is a structural schematic diagram of a three-dimensional pulse sensor, the three-dimensional pulse sensor 00 includes a flexible substrate 10 and a flexible probe 20. A 3×3 array pressure sensor 11 is printed on the flexible substrate 10, and the 3×3 array pressure sensor 11 includes nine pressure sensing areas 111, which is convenient for locating the pulse position. The flexible probe 20 is composed of a hemispherical silicone structure 21 and a photoelectric capacitance sensor 22. The convex surface of the hemispherical silicone structure 21 contacts the skin, and the photoelectric capacitance sensor 22 is embedded in the convex surface. The other side of the hemispherical silicone structure 21 is a plane, and the pressure sensing area 111 on the flexible substrate 10 is bonded with epoxy resin, which does not affect signal conduction and is convenient. The hemispherical silicone structure 21 can better fit the skin surface of the human body, reduce the discomfort that may be caused by hard sensors, and also reduce the introduction of irrelevant noise (such as electromyographic interference). The nine flexible probes 20 correspond to the nine pressure sensing areas 111 on the flexible substrate 10, covering the pulse area of ​​the wrist of the subject. The size of the pressure sensing area 111 is 3.5×3.5 mm, the interval between two adjacent pressure sensing areas 111 is 0.5 mm, the diameter of the hemispherical silicone structure 21 is 3.5 mm, and the size of the three-dimensional pulse sensor 00 is 14×14×4 mm.

[0044] In the present invention, the array pressure sensor 11 is composed of a polyester film 112, a highly conductive material 113 and a nano-scale pressure-sensitive material 114. The top layer (sensing layer) 115 is a flexible film and a pressure-sensitive material composited thereon, and the bottom layer 116 is a flexible film and a conductive metal layer composited thereon. The two are attached by double-sided tape and the sensing areas of the upper and lower layers are isolated. The photoelectric capacitance sensor 22 is composed of three 530nm green LEDs 221, a 660nm red LED 222, a 950nm infrared LED 223, a photodetector 224 and two light baffles 225. It works by using LEDs to shine light into the skin, and then the blood and surrounding tissues will absorb different amounts of light, and other light that is not absorbed will return to the photodetector 224, and then through different absorption weight measurement and LED wavelengths to read pulse rate and blood oxygen saturation level.

[0045] Please refer to Figure 2 , is a structural schematic diagram of a three-dimensional pulse acquisition device, a three-dimensional pulse acquisition device includes a three-dimensional pulse sensor 00, a conditioning conversion device 30 and a three-dimensional pulse processing device 40.

[0046] In the present invention, the conditioning conversion device 30 includes a conditioning circuit 31 and a digital-to-analog conversion circuit 32. The conditioning circuit 31 pre-processes the initial pressure pulse signal and the photoplethysmography signal, and transmits the processed pressure pulse signal and the photoplethysmography signal to the digital-to-analog conversion circuit 32. The digital-to-analog conversion circuit 32 converts the analog signal preliminarily processed by the conditioning circuit 31 into a digital signal. The three-dimensional pulse processing device is used for fitting the three-dimensional pulse signal, displaying the three-dimensional pulse waveform in real time, and storing the three-dimensional pulse signal data.

[0047] The number of sensing units in the conditioning circuit 31 and the three-dimensional pulse sensor 00 is the same, please refer to Figure 3 , is a principle block diagram of the conditioning circuit 31. Each conditioning circuit 31 consists of a primary amplifying circuit 311, a zeroing circuit 312, an industrial frequency limiting circuit 313, a bandpass filter circuit 314 and a secondary amplifying circuit 315, and sends the processed signal to the digital-to-analog conversion circuit 32.

[0048] Please refer to Figures 4 to 8 , Figure 4 is a schematic diagram of a first-stage amplifier circuit 311 according to an embodiment of the present invention, Figure 5 is a schematic diagram of the zero adjustment circuit 312 according to an embodiment of the present invention, Figure 6 is a schematic diagram of the power frequency limiting circuit 313 according to an embodiment of the present invention, Figure 7 is a schematic diagram of a bandpass filter circuit 314 according to an embodiment of the present invention, Figure 8 3 is a schematic diagram of a secondary amplifier circuit 315 according to an embodiment of the present invention.

[0049] In the present invention, each primary amplifier circuit 311 is connected to a sensor unit, and the primary amplifier circuit 311 is used to perform primary amplification on the pulse signal output by a sensor unit; the zero adjustment circuit 312 is respectively connected to the power frequency limiting circuit 313 and each primary amplifier circuit 311, and is used to further suppress the baseline drift caused by factors such as muscle tremor, human body tension, and respiratory tremor, so as to ensure that when the input is zero, the output of the entire circuit is zero; the power frequency limiting circuit 313 is connected to the bandpass filter circuit 314, and is used to eliminate the 50H mains voltage. The bandpass filter is composed of a high-pass filter 3141 and a low-pass filter 3142; the bandpass filter circuit 314 is connected to a secondary amplifier circuit 315, and the frequency band range of the circuit is approximately 0.05Hz to 40Hz, which includes the main energy components of the pulse signal and is used to separate the useful components of the pulse signal from the collected signal; the secondary amplifier circuit 315 is connected to the digital-to-analog conversion circuit 32, and is used to perform secondary amplification on the filtered pulse signal and output the secondary amplified pulse signal to the digital-to-analog conversion circuit 32.

[0050] Please refer to Fig. 9 , which is a principle block diagram of digital-to-analog conversion. The digital-to-analog conversion circuit 32 includes an FPGA321 and two 10-channel ADC chips 322. The FPGA321 controls the two 10-channel ADC chips 322 to collect 9-channel pressure analog signals and 9-channel photoelectric analog signals from the three-dimensional pulse sensor 00, and convert them into 18-channel digital signals. At the same time, the FPGA321 is used to perform synchronous processing of the 18-channel digital signals, including a FIFO data buffer 323 and a serial port transmission 324 to the three-dimensional pulse processing device 40.

[0051] The three-dimensional pulse processing device 40 includes three-dimensional pulse signal fitting and data display memory. By applying the spline curve fitting algorithm, the array signals collected at the same time are horizontally fitted, and then the discrete moment signals are arranged according to the time series. Multiple one-dimensional signals are thus constructed into a complete three-dimensional pulse signal. The specific three-dimensional pulse signal fitting includes two steps. The first step is to perform spline interpolation fitting on the array signals perpendicular to the wrist direction at the same time, and the second step is to sort the fitted curves in time sequence. The data display memory is to display the three-dimensional pulse signal on the host computer 41 and save it.

[0052] The three-dimensional pulse sensor and its acquisition device of the present invention have a simple structure and can achieve the purpose of accurately locating the key parts of the subject's wrist. In addition, each pressure sensing area 111 and each photoelectric capacitance sensor 22 of the three-dimensional pulse sensor 00 are independent of each other. Compared with the traditional single array pressure sensor 11, it has lower cost and is more convenient to use, and can also collect pulse signals from all directions and multiple levels. At the same time, the hemispherical silicone structure 21 can protect the pressure sensing area 111 and the photoelectric capacitance sensor 22, and improve the robustness and service life of the three-dimensional pulse sensor 00.

[0053] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A three-dimensional pulse sensor, characterized in that: The three-dimensional pulse sensor (00) comprises a flexible substrate (10) and a flexible probe (20); A 3×3 array pressure sensor (11) is printed on the flexible substrate (10), and the 3×3 array pressure sensor (11) includes nine pressure sensing areas (111) to facilitate the positioning of the vein position; The flexible probe (20) is composed of a hemispherical silicone structure (21) and a photoelectric capacitance sensor (22); the convex surface of the hemispherical silicone structure (21) contacts the skin, the photoelectric capacitance sensor (22) is embedded in the convex surface, and the other side of the hemispherical silicone structure (21) is a flat surface, which is bonded to the pressure sensing area (111) on the flexible substrate (10); The nine flexible probes (20) correspond to the nine pressure sensing areas (111) on the flexible substrate (10), and cover key pulse areas on the wrist of the subject.

2. A three-dimensional pulse sensor according to claim 1, characterized in that: The size of the pressure sensing area (111) is 3.5×3.5 mm, the interval between two adjacent pressure sensing areas (111) is 0.5 mm, the diameter of the hemispherical silicone structure (21) is 3.5 mm, and the size of the three-dimensional pulse sensor (00) is 14×14×4 mm.

3. A three-dimensional pulse sensor according to claim 1, characterized in that: The array pressure sensor (11) is a piezoelectric film sensor, and the photoelectric capacitance sensor (22) is composed of three 530nm green LEDs (221), a 660nm red LED (222), a 950nm infrared LED (223), a photodetector (224), and two light baffles (225).

4. A three-dimensional pulse acquisition device, characterized in that: The three-dimensional pulse collection device also includes a conditioning conversion device (30) and a three-dimensional pulse processing device (40); The conditioning conversion device (30) comprises a conditioning circuit (31) and an analog-to-digital conversion circuit (32), wherein the conditioning circuit (31) pre-processes an initial pressure pulse signal and a photoplethysmography signal, and transmits the processed pressure pulse signal and the photoplethysmography signal to the digital-to-analog conversion circuit (32), and the digital-to-analog conversion circuit (32) converts the analog signal preliminarily processed by the conditioning circuit (31) into a digital signal; The three-dimensional pulse processing device (40) is used for fitting the three-dimensional pulse signal, displaying the three-dimensional pulse waveform in real time, and storing the three-dimensional pulse signal data; The three-dimensional pulse acquisition device is applied to the three-dimensional pulse sensor as claimed in any one of claims 1 to 3.

5. A three-dimensional pulse acquisition device according to claim 4, characterized in that: The number of the conditioning circuits (31) is the same as the number of the sensors, and each conditioning circuit (31) is composed of a primary amplification circuit (311), a zero adjustment circuit (312), an industrial frequency limiting circuit (313), a bandpass filter circuit (314) and a secondary amplification circuit (315), and sends the processed signal to the digital-to-analog conversion circuit (32).

6. A three-dimensional pulse acquisition device according to claim 4, characterized in that: The digital-to-analog conversion circuit comprises an FPGA (321) and two 10-channel ADC chips (322). The FPGA (321) controls the two 10-channel ADC chips (322) to collect 9-channel pressure analog signals and 9-channel photoelectric analog signals from the three-dimensional pulse sensor (00), and converts them into 18-channel digital signals. The FPGA (321) is used to synchronously process the 18-channel digital signals, including a FIFO data buffer (323) and serial port transmission (324) to a three-dimensional pulse processing device (40).

7. A three-dimensional pulse acquisition device according to claim 4, characterized in that: The three-dimensional pulse processing device (40) includes three-dimensional pulse signal fitting and data display storage. The three-dimensional pulse signal fitting includes two steps. The first step is to perform spline interpolation fitting on the array signal perpendicular to the wrist direction at the same time. The second step is to sort the fitted curves in time sequence. The data display storage is used to display the pressure three-dimensional pulse signal and the photoelectric three-dimensional pulse signal on the host computer (41) and save them.

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