A method for identifying tight pulse features based on the transverse position change of pulse wave measured by sensor array

Abstract

The present invention provides a method for identifying tight pulse characteristics based on measuring the transverse position change of pulse wave by a sensor array. The sensor array includes at least 4 pressure sensors, each of which is arranged along a first direction, and the first direction is set at an angle with the extension direction of the radial artery. The method for identifying tight pulse characteristics in traditional Chinese medicine includes: obtaining the pulse pressure value of each pressure sensor at the same time; obtaining multiple pressure sampling points, and connecting each pressure sampling point into an envelope curve; obtaining multiple envelope curves in the same pulse cycle, selecting the envelope curve corresponding to the maximum value of the ordinate as the pressure distribution curve of the pulse cycle, taking an identification point in each pressure distribution curve to represent the position of the pressure distribution curve, and counting the change amount of the abscissa of each identification point; comparing the change amount with the tight pulse judgment threshold, and obtaining the tight pulse characteristic recognition result. The method for identifying tight pulse characteristics based on measuring the transverse position change of pulse wave by a sensor array of the present invention can identify complex pulse conditions such as tight pulse.

Description

Technical Field

[0001] The invention relates to the technical field of medical sensors, and in particular to a method for identifying tight pulse features based on measuring lateral position changes of pulse waves by a sensor array. Background Art

[0002] Pulse diagnosis in traditional Chinese medicine has a history of more than 2,000 years, from the early all-round diagnosis method to the Cunkou pulse method, which is to identify the pulse by measuring the pulse signal of the radial artery at the Cunkou of the wrist with fingers to identify the pulse condition. Currently, the generally recognized pulse conditions can be divided into 28 types.

[0003] Tight pulse is one of the 28 pulse signs in TCM pulse diagnosis. TCM describes it as: "Tight pulse is like a twisting rope" [Zhang Zhongjing, "Treatise on Febrile and Miscellaneous Diseases in Baiyun Pavilion", Volume 2, "Pulse Method (Part 2), Chinese Medicine Ancient Books Publishing House, 2017]. "Lifting is like twisting rope and cutting is like rope, so the pulse sign is called tight" [Liu Wenlong et al., "Binghu Pulse Study in Vernacular", People's Medical Publishing House, page 48, 2013]. It can be learned from ancient Chinese medicine books that tight pulse has a feeling similar to the twisting of hemp rope and the left and right snapping of fingers. Therefore, many schools of TCM believe that tight pulse has the periodic instability of the lateral swing of the pulse wave. The periodic instability of the lateral swing of the pulse wave constitutes the core feature of tight pulse.

[0004] Since the 1960s, domestic and foreign researchers have conducted long-term research on pulse diagnosis informatization, achieved a lot of results, and developed a variety of pulse diagnosis instruments. Due to the large size of the pressure or strain sensors used, existing pulse diagnosis instruments generally use no more than 3 sensors for pulse diagnosis measurement. The sensors are pressed on the radial artery at the Cunkou point through external loading to obtain the pressure-time curve of the pulse wave under a specific loading pressure, and the pulse condition is identified by analyzing the curve of the pressure amplitude changing with time. Obviously, the measurement principle of the existing pulse diagnosis instrument is significantly different from that of traditional Chinese medicine, and it cannot identify all 28 pulses, especially it does not have the ability to identify complex pulse characteristics such as tight pulse. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for identifying tight pulse characteristics based on measuring the lateral position change of the pulse wave by a sensor array, so as to solve the problem that it is difficult to identify complex pulse conditions such as tight pulse in the prior art.

[0006] To achieve the above-mentioned object and other related objects, the present invention provides a method for identifying tight pulse features based on measuring the lateral position change of pulse wave by a sensor array, wherein the sensor array comprises at least 4 pressure sensors, each of which is arranged along a first direction, and the first direction is arranged at an angle to the extension direction of the radial artery. The method for identifying tight pulse features in traditional Chinese medicine comprises:

[0007] Obtaining the pulse pressure value of each pressure sensor at the same time;

[0008] Taking the position of the pressure sensor in the first direction as the abscissa and the pulse pressure value measured by the pressure sensor as the ordinate, a plurality of pressure sampling points are obtained, and each of the pressure sampling points is connected to form an envelope curve, wherein the envelope curve is used to represent the distribution state of the pulse pressure in the first direction at that moment;

[0009] Obtain multiple envelope curves within the same pulse cycle, compare the maximum values ​​of the ordinates of the envelope curves, and select the envelope curve corresponding to the maximum value of the ordinate as the pressure distribution curve of the pulse cycle;

[0010] Obtaining pressure distribution curves of a plurality of consecutive pulse cycles, taking a mark point in each of the pressure distribution curves to represent the position of the pressure distribution curve, and counting the change in the abscissa of each of the mark points, wherein the change is used to indicate the degree of instability of the lateral position of the pulse between different pulse cycles;

[0011] The change amount is compared with the tight pulse determination threshold to obtain a tight pulse feature recognition result.

[0012] The center distance between two adjacent pressure sensors is no more than 1.25 mm.

[0013] The angle between the first direction and the extension direction of the radial artery is α, 45°≤α≤135°.

[0014] Preferably, the first direction is perpendicular to the extension direction of the radial artery, that is, α=90°.

[0015] The total span of the sensor array is not less than 3.75 mm.

[0016] The more synchronized the sampling time of the sensors in the array is, the better. In actual operation, the asynchronous beat does not exceed 0.1 second.

[0017] Preferably, the method for selecting the identification point includes:

[0018] Calculate the lower limit of pressure by multiplying the maximum value of the ordinate of the pressure distribution curve by a preset coefficient, wherein the preset coefficient is 1 / 7 to 5 / 7;

[0019] Obtaining a reference horizontal line parallel to the abscissa axis, wherein the ordinate value of the reference horizontal line is equal to the lower limit value of the pressure;

[0020] The area enclosed by the reference horizontal line and the pressure distribution curve is the envelope reference area.

[0021] The identification points are selected using the following formula:

[0022]

[0023]

[0024] Wherein, i represents the serial number of the pressure sensor;

[0025] x i Represents the channel number of the i-th acquisition channel;

[0026] y i Represents the pressure value of the i-th acquisition channel;

[0027] w i represents the weight of the i-th pressure sensor;

[0028] h represents the height coefficient of the marking point, 0≤h≤1;

[0029] vld_chns indicates the number of each acquisition channel.

[0030] Preferably, the variation is the standard deviation of the horizontal coordinates of each of the identification points.

[0031] As described above, the method for identifying tight pulse features based on the sensor array measuring the lateral position change of the pulse wave of the present invention has at least one of the following advantages:

[0032] 1) It overcomes the limitation that a single-point sensor cannot sensitively sense the lateral position movement signal of the pulse;

[0033] 2) The sensor array can draw the pulse width envelope curve, eliminating the limitation that the previous sensor unit can only obtain the pulse wave timing diagram;

[0034] 3) Combine the pulse wave timing diagram and the envelope curve diagram, and finally complete the identification of tight pulse according to the changing rules of envelope shape and position. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Shown is a schematic flow chart of a method for identifying tight pulse characteristics in Traditional Chinese Medicine according to an embodiment of the present invention.

[0036] Figure 2 It is a schematic flow chart of a variation calculation method according to an embodiment of the present invention.

[0037] Figure 3 Shown is a schematic diagram of an application scenario of the Traditional Chinese Medicine tight pulse feature recognition method in one embodiment of the present invention.

[0038] Figure 4 Shown is a schematic diagram of an application scenario of the Traditional Chinese Medicine tight pulse feature recognition method of the present invention in another embodiment.

[0039] Figure 5 A schematic diagram showing the span of a sensor array and the sensor spacing according to an embodiment of the present invention is shown.

[0040] Figure 6 Shown is a schematic diagram of envelope curves of different pulse cycles collected by a sensor array according to an embodiment of the present invention.

[0041] Figure 7 Shown is a diagram showing the calculation principle of the marker points according to an embodiment of the present invention.

[0042] Figure 8 Shown is an envelope curve diagram drawn by an array of 18 micro pressure sensors (0-17 channels) according to an embodiment of the present invention.

[0043] Fig. 9 It is a schematic diagram showing the present invention using the Catmull-Rom Splines algorithm to connect discrete points.

[0044] Fig.10 Shown is a diagram showing the calculation principle of the marker points according to an embodiment of the present invention.

[0045] Fig.11 Displayed as a location distribution map of the marker points.

[0046] Component number description

[0047] 1. Radial artery; 2. Sensor array; 3. Envelope curve; 4. Flexible substrate; 5. Pressure sensor; 6. Center distance between two adjacent microsensors in the array; 7. Total span of the array. DETAILED DESCRIPTION

[0048] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0049] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0050] Existing pulse diagnosis instruments collect the pressure amplitude change curve under a specific loading pressure over time, which makes it difficult to identify complex pulse conditions such as tight pulse.

[0051] like Figures 1 to 11As shown, the diagrams provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention, and the diagrams and expressions only show the preprocessing algorithms related to the present invention rather than the operating steps strictly followed in actual implementation. The requirements, sequence, operation, algorithm parameters and thresholds of each step in the actual implementation can be flexibly adjusted according to the actual sensor accuracy, arrangement density, data preprocessing conditions and the gender, age, weight and pulse width of the person to be measured, and the analysis steps and operating procedures may also be simplified or more complicated.

[0052] The present invention provides a method for identifying tight pulse features based on measuring the lateral position change of pulse waves by a sensor array. The sensor array 2 includes at least four pressure sensors 5. Each pressure sensor 5 is arranged along a first direction. The first direction is perpendicular to the extension direction of the radial artery 1. The method for identifying tight pulse features in traditional Chinese medicine includes:

[0053] Step S100, obtaining the pulse pressure values ​​of each pressure sensor 5 at the same time. The same time in the present invention means that the sampling time difference of each pressure sensor 5 is within 0.1 second. In other words, a certain range of deviation is allowed for the sampling time points of each pulse pressure value. As long as the time interval between any two sampling time points is less than 0.1 second, it is considered that the sampling is at the same time.

[0054] Step S200, taking the position of the pressure sensor 5 in the first direction as the abscissa and the pulse pressure value measured by the pressure sensor 5 as the ordinate, obtaining a plurality of pressure sampling points, connecting the pressure sampling points into an envelope curve 3, and the envelope curve 3 is used to represent the distribution state of the pulse pressure in the first direction at that moment;

[0055] Step S300, obtaining multiple envelope curves within the same pulse cycle, comparing the maximum values ​​of the ordinates of the envelope curves, and selecting the envelope curve corresponding to the maximum ordinate value as the pressure distribution curve of the pulse cycle;

[0056] Step S400, obtaining pressure distribution curves of a plurality of consecutive pulse cycles, taking a mark point in each pressure distribution curve to represent the position of the pressure distribution curve, and counting the change amount of the abscissa of each mark point, the change amount is used to indicate the degree of instability of the lateral position of the pulse between different pulse cycles;

[0057] Step S500, comparing the change amount with the tight pulse determination threshold to obtain a tight pulse feature recognition result.

[0058] The present embodiment does not limit the arrangement of the pressure sensors 5 along a straight line. In fact, the pressure sensors 5 can be arranged along a space curve. When the pressure sensors 5 are arranged along a space curve such as an arc, the tangent direction of the space curve can be regarded as the first direction. The first direction is set to be perpendicular to the extension direction of the radial artery 1 in order to obtain the distribution information of the pulse pressure value on the transverse section. The distribution information is difficult to accurately obtain with the existing single-point pulse diagnosis instrument. The inventor has found that the morphology and distribution information on the transverse section have important reference value for the identification of complex pulse conditions such as tight pulse.

[0059] The pulse pressure value of this embodiment has both a time dimension and a space dimension. In order to obtain the spatial distribution information of the pulse pressure value, it is necessary to unify the time dimension of the pulse pressure value. Ideally, the pulse pressure values ​​collected at the same time are the most credible and have the most reference value. However, due to the limitation of the precision of the actual measuring instrument, it is difficult to ensure that the collection time of the pulse pressure value is strictly synchronized. Therefore, the time interval between the sampling time points of any two sensors is controlled within a preset time length, for example, within 0.1 seconds, that is, it is considered to be sampled at the same time.

[0060] The envelope curve 3 of this embodiment reflects the distribution of the pulse pressure value along the first direction when the pulse occurs. The first direction is roughly consistent with the cross-sectional direction of the radial artery 1, and a small deviation is allowed in actual operation. The horizontal coordinate of the pressure sampling point can be in units of distance or can represent the arrangement sequence of the pressure sensor 5 without dimension, as long as the relative position relationship of each pressure sensor 5 can be derived based on the horizontal coordinate.

[0061] The ordinate of the pressure sampling point is the pulse pressure value. The pressure of the pressure sensor 5 includes both the pressing force used to press the sensor array 2 against the human body and the additional pressure caused by the pulse. Since the pressing force is not very meaningful for data analysis, the pulse pressure value can be the actual measurement value of each pressure sensor 5 minus the same pressing force value. The pressing force value can be set manually and has little effect on the accuracy of the recognition result.

[0062] According to the experience recorded in TCM literature, the tight pulse generally exhibits the characteristics of "like a twisting rope" and "bouncing around in one's hand". "Twisting rope" is a metaphor used by the ancients to make a rope by twisting a vertebra, which is intended to express the tightness of the rope and the bounce feeling caused by the unevenness between the strands when the rope rotates, but not the rotation feeling. This embodiment captures the characteristics of "like a twisting rope" and "bouncing around in one's hand" by the overall lateral movement of the envelope curve 3.

[0063] There may be differences in shape between pressure distribution curves of different pulse cycles. For the convenience of calculation, this embodiment uses a specific identification point to represent the position of the pressure distribution curve. It should be noted that this embodiment does not limit the position of the identification point to coincide with the pressure distribution curve. In fact, the identification point can also be located outside the pressure distribution curve. The threshold for determining a tight pulse in this embodiment can be set based on experience.

[0064] In summary, this embodiment increases the spatial dimension of the pulse pressure value by adopting the sensor array 2, and expands the one-dimensional pulse longitudinal time series signal that can only be measured by a single-point pulse diagnosis instrument in the past into a two-dimensional signal of longitudinal time series plus transverse section, which is more in line with the description of tight pulse in traditional Chinese medicine literature. This embodiment identifies "lateral swing" as a tight pulse feature, which is not only convenient for characterization by measuring instruments, but also meets the understanding of tight pulse by different schools of traditional Chinese medicine. This embodiment also quantifies the degree of pulse swing through the pressure distribution curve and the identification point, and compares it with the empirical value to obtain the tight pulse feature recognition result. The physician can refer to the tight pulse feature recognition results and other clinical indicators, make a comprehensive judgment, and draw a diagnosis conclusion.

[0065] In this embodiment, the sampling frequency of the pressure sensor for the pulse pressure value is above 16 Hz.

[0066] Specifically, in this embodiment, the sampling frequency of each pressure sensor 5 for the pulse pressure value is 800 Hz.

[0067] In order to ensure the consistency of the pressing pressure of the pressure sensor 5 and highlight the proportion of the actual pulse pressure in the pulse pressure value, in this embodiment, the sensor array 2 includes a long flexible substrate 4, and the pressure sensor 5 is installed on the flexible substrate 4.

[0068] In this embodiment, the center distance 6 between two adjacent pressure sensors 5 is no greater than 1.25 mm.

[0069] Specifically, in this embodiment, the center distance 6 between two adjacent pressure sensors 5 is 0.65 mm.

[0070] In this embodiment, the angle between the first direction and the extension direction of the radial artery 1 is α, and 45°≤α≤135°.

[0071] Specifically, in this embodiment, the first direction is perpendicular to the extension direction of the radial artery 1 , that is, α=90°.

[0072] like Figure 5 As shown, in this embodiment, the total span 7 of the sensor array 2 is not less than 3.75 mm to ensure that the sensor array 2 can cover the radial artery 1 and nearby related areas. In order to improve the measurement accuracy, a micro pressure sensor 5 can be used.

[0073] Specifically, in this embodiment, the total span 7 of the sensor array 2 is 11.05 mm.

[0074] In order to ensure the consistency of the measurement time of each pressure sampling point in the envelope curve 3, in this embodiment, the span of the same time period is less than 0.1 second.

[0075] In this embodiment, if Figure 8 As shown, the sensor array includes 18 pressure sensors, which are divided into channels 0 to 17. The vertical axis is the pulse pressure value after removing the DC component, in kPa.

[0076] In this embodiment, if Fig. 9 As shown, the Catmull-Rom Splines algorithm is used to connect the pressure sampling points into an envelope curve 3. Among them, P0 and P1 are the points to be smoothly connected; P -1 P1 and P2 are control points that determine the trend and curvature of the connecting line. The Catmull-Rom Splines algorithm can refer to the prior art.

[0077] To construct the curve P(t) between the pressure sampling point P0 and the pressure sampling point P1. P(t) is the following cubic curve to be solved:

[0078] P(t)=at 3 +bt 2 +ct+d

[0079] P -1 and P2 are control points. Then:

[0080]

[0081] In actual implementation, other algorithms for smoothly connecting discrete points may also be used, not limited to the Catmull-Rom Splines algorithm of this embodiment.

[0082] In this embodiment, the degree of change in the transverse position is quantified by the standard deviation of the horizontal coordinates of the marking points of the pulse cross-section envelope diagram of four consecutive cycles.

[0083] In this embodiment, the method for identifying tight pulse features based on the sensor array measuring the lateral position change of the pulse wave includes the following steps:

[0084] like Figure 3 As shown, the radial artery 1 is measured by a sensor array 2 in a floating manner to obtain an envelope curve 3 of the closed position in the cross-sectional direction.

[0085] like Figure 6As shown, the pulse pressure values ​​of at least four consecutive pulse wave cycles of the sensor array 2 are continuously recorded to obtain at least four pressure distribution curves. The four pressure distribution curves correspond to four pulse wave cycles respectively.

[0086] In this embodiment, the following formula is used to calculate the marking point P of the pressure distribution curve:

[0087]

[0088]

[0089] Wherein, i represents the serial number of the pressure sensor;

[0090] x i Represents the channel number of the i-th acquisition channel;

[0091] y i Represents the pressure value of the i-th acquisition channel;

[0092] w i represents the weight of the i-th pressure sensor;

[0093] h represents the height coefficient of the marking point, 0≤h≤1;

[0094] vld chnsi Indicates the number of the effective channel. The effective channel is the channel that can effectively sense the pulse pressure condition, usually provided by several sensors just above the blood vessels.

[0095] Based on the above formula, different identification points can be obtained by adjusting the weight and height coefficient of each pressure sensor.

[0096] Specifically, Figure 7 As shown, when the weights w of all valid channels (i.e., pressure sensors) i When both are equal to 1 and h = 0.5, the marked point P is the center of gravity G:

[0097]

[0098]

[0099] When the weight of the leftmost valid channel is 1 and the weights of the other channels are 0, h=1, the identification point P is the leftmost endpoint of the valid channel.

[0100] When the weights of the two valid channels at both ends are 1 and the weights of the other channels are 0, h=0, the identification point P is the midpoint of the base of the valid channel.

[0101] When the weight of the channel with the highest amplitude is 1 and the weights of the other channels are 0, h=1, the marked point P is the peak point of the pressure distribution curve.

[0102] It should be noted that there are many identification points that can be used to identify and quantify the lateral position change of the pressure distribution curve, including but not limited to the above types, as long as formula (1) and formula (2) are satisfied.

[0103] If certain indicators of the horizontal coordinates of the identification points of multiple consecutive cycles exceed a preset threshold, it can be considered that the pressure distribution curve has undergone periodic lateral deviation, which can be identified as the lateral instability of the pulse wave of the tight pulse. The indicators that can be used for measurement include but are not limited to: skewness, maximum deviation, average deviation, proportion of deviation in pulse width, variance, standard deviation, coefficient of variation, etc.

[0104] In this embodiment, the method for setting the threshold value for determining tight pulse is as follows: by measuring the values ​​of the above-mentioned indicators in the test group and the control group, the threshold values ​​for tight pulse and non-tight pulse are defined according to the distribution of the values, so as to maximize the discrimination. For example, a number of tight pulse patients and normal pulse volunteers (normal people) are selected, and the sensor array for measuring is floated and pressed on the closed position of the human radial artery 1, and the sensor arrangement direction is perpendicular to the flow direction of the radial artery 1. The marking points of the pressure distribution curve of each person for no less than 4 consecutive pulse wave cycles are recorded. If the measurement indicator is selected as the standard deviation of the horizontal coordinate of the marking point, the threshold value for the division of the indicator under the hardware platform is calibrated according to the distribution of the standard deviation of normal pulse volunteers and tight pulse patients. Usually, the standard deviation of the normal pulse is approximately equal to 0; while the standard deviation of the tight pulse will obviously deviate from 0. The threshold value can be taken as the mean between the maximum measured value of the normal pulse standard deviation and the minimum measured value of the tight pulse standard deviation, or it can be defined according to the experience or scale of the traditional Chinese medicine physician himself. More personalized thresholds can be further subdivided and calibrated based on sensor sensitivity, arrangement density, sample gender, age, weight, pulse width, and the mathematical properties of the selected indicators.

[0105] like Figure 2 , Fig.10 As shown, in this embodiment, in step S400, the method for selecting the identification point includes:

[0106] Step S410, calculate the lower limit of pressure by multiplying the maximum value of the ordinate of the pressure distribution curve by a preset coefficient, where the preset coefficient is 1 / 7 to 5 / 7. The pressure distribution curve generally contains a main peak and may also contain other peaks. The maximum value of the ordinate of the pressure distribution curve is generally the ordinate of the vertex of the main peak of the pressure distribution curve. Specifically, the preset coefficient is 1 / 3.

[0107] Step S420, obtain a reference horizontal line parallel to the horizontal axis, the vertical coordinate value of the reference horizontal line is equal to the lower limit of pressure. By setting the reference horizontal line, the data is further filtered, and the pressure sampling points involved in tight pulse identification are closer to the peak area of ​​the pulse, thereby improving the accuracy of tight pulse identification.

[0108] Step S430: The area enclosed by the reference horizontal line and the pressure distribution curve is the envelope reference area, and the center of gravity G of the envelope reference area is used as the identification point.

[0109] The sample of this embodiment contains 8 continuous pulse wave cycles. The horizontal coordinates of the 8 identification points are 11.4695, 11.3574, 11.2625, 11.2103, 11.1283, 11.1123, 11.1296, 11.1436, 11.094, and their standard deviation is 0.1258. According to the hardware platform and data preprocessing of this example, the threshold value k for determining tight pulse is determined to be 0.11. However, 0.1258 ≥ 0.11, so the pulse recognition conclusion is -- tight pulse.

[0110] The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. When the technical features in different embodiments are embodied in the same figure, it can be regarded that the figure also discloses the combination examples of the various embodiments involved.

[0111] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for identifying tight pulse features based on measuring the lateral position change of pulse waves using a sensor array, characterized in that: The sensor array includes at least 4 pressure sensors, each of which is arranged along a first direction, and the first direction is arranged at an angle with the extension direction of the radial artery. The tight pulse feature recognition method includes: Obtaining the pulse pressure value of each pressure sensor at the same time; Taking the position of the pressure sensor in the first direction as the abscissa and the pulse pressure value measured by the pressure sensor as the ordinate, a plurality of pressure sampling points are obtained, and each of the pressure sampling points is connected to form an envelope curve, wherein the envelope curve is used to represent the distribution state of the pulse pressure in the first direction at that moment; Obtain multiple envelope curves within the same pulse cycle, compare the maximum values ​​of the ordinates of the envelope curves, and select the envelope curve corresponding to the maximum ordinate value as the pressure distribution curve of the pulse cycle; Obtaining pressure distribution curves of a plurality of consecutive pulse cycles, taking a mark point in each of the pressure distribution curves to represent the position of the pressure distribution curve, and counting the change in the abscissa of each of the mark points, wherein the change is used to indicate the degree of instability of the lateral position of the pulse between different pulse cycles; Comparing the change amount with a tight pulse determination threshold to obtain a tight pulse feature recognition result; The center distance between two adjacent pressure sensors is no more than 1.25 mm; The angle between the first direction and the extension direction of the radial artery is α, 45°≤α≤135°.

2. The method for identifying tight pulse features based on measuring the lateral position change of pulse wave by a sensor array according to claim 1, characterized in that: The first direction is perpendicular to the extension direction of the radial artery.

3. The method for identifying tight pulse features based on measuring the lateral position change of pulse wave by a sensor array according to claim 1, characterized in that: The total span of the sensor array is not less than 3.75 mm.

4. The method for identifying tight pulse features based on measuring the lateral position change of pulse wave by a sensor array according to claim 1, characterized in that: The method for selecting the identification points includes: Calculate the lower limit of pressure by multiplying the maximum value of the ordinate of the pressure distribution curve by a preset coefficient, wherein the preset coefficient is 1 / 7 to 5 / 7; Obtaining a reference horizontal line parallel to the abscissa axis, wherein the ordinate value of the reference horizontal line is equal to the lower limit value of the pressure; The area enclosed by the reference horizontal line and the pressure distribution curve is the envelope reference area.

5. The method for identifying tight pulse features based on measuring the lateral position change of pulse wave by a sensor array according to claim 1, characterized in that: The identification points are selected using the following formula: Wherein, i represents the serial number of the pressure sensor; x i Represents the channel number of the i-th acquisition channel; y i Represents the pressure value of the i-th acquisition channel; w i represents the weight of the i-th pressure sensor; h represents the height coefficient of the marking point, 0≤h≤1; vld_chns indicates the number of each acquisition channel.

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