CN-122004873-A - Flexible electrode array method for non-contact vital sign monitoring

CN122004873ACN 122004873 ACN122004873 ACN 122004873ACN-122004873-A

Abstract

The invention discloses a flexible electrode array method for non-contact vital sign monitoring, which relates to the field of biomedical engineering and solves the problems of interference and inaccurate monitoring of vital sign monitoring, and the method comprises the steps of setting the layout of a flexible electrode array according to the human body size and the measurement range of the flexible electrode, and constructing a vital sign monitoring mattress based on the layout of the flexible electrode array; the method comprises the steps of analyzing a transmission flow of electrocardiosignals according to a capacitance sensing principle, judging the eligibility of a flexible electrode array, adjusting an unqualified flexible electrode array, measuring capacitance data of the flexible electrode array when a user to be tested sleeps, identifying sleeping positions and sleeping position changes of the user to be tested based on the capacitance data, and outputting sleeping position data of the user to be tested and measured electrocardiosignal data by pertinently positioning and starting the corresponding electrocardiosignal electrodes according to the sleeping positions of the user to be tested.

Inventors

FENG BAOLIANG
XU XIANGMIN
XIONG QIWEI
WANG LEHAN
WANG KAIKAI
XING XIAOFEN
SHU LIN

Assignees

华南理工大学

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (10)

1. A method of flexible electrode array for non-contact vital sign monitoring, the method comprising: Step S1, setting the layout of a flexible electrode array according to the human body size and the measurement range of the flexible electrode, and constructing a sign monitoring mattress based on the layout of the flexible electrode array; Step S2, analyzing the transmission flow of electrocardiosignals according to a capacitance sensing principle, judging the qualification of the flexible electrode array, and adjusting the unqualified flexible electrode array; Step S3, measuring capacitance data of the flexible electrode array of the user to be tested during sleeping, and identifying sleeping posture and sleeping posture change of the user to be tested based on the capacitance data; And S4, positioning and starting the flexible electrode array in a targeted manner to monitor by taking the sleeping posture of the user to be detected as a basis, and outputting sleeping posture data of the user to be detected and the electrocardiographic data obtained by measurement.
2. A method of flexible electrode array for non-contact vital sign monitoring according to claim 1, wherein said step S1 comprises the sub-steps of: Step S11, acquiring the human shoulder width range of an adult, and reading the upper limit value of the shoulder width of the human shoulder width range; step S12, setting the abduction occupation width and the unilateral turning allowance of an adult during sleeping; Step S13, obtaining the width of the electrode array by adding the upper limit value of the shoulder width and the natural abduction width and adding two times of unilateral turning allowance; Step S14, acquiring a trunk length range of an adult, and reading a trunk length upper limit value of the trunk length range; step S15, setting the sleep posture extension length, and obtaining the electrode array length by adding the upper limit value of the trunk length to the sleep posture extension length.
3. A method of flexible electrode array for non-contact vital sign monitoring according to claim 2, wherein said step S1 further comprises the sub-steps of: Step S16, reading a measuring range of the flexible electrode, and identifying a single-side measuring length of the corresponding flexible electrode, wherein the number of the flexible electrodes in the horizontal direction is obtained by dividing the width of the electrode array by the single-side measuring length, and the number of the flexible electrodes in the vertical direction is obtained by dividing the length of the electrode array by the single-side measuring length; obtaining the total number of the electrodes in the flexible electrode array by multiplying the number of the flexible electrodes in the horizontal direction by the number of the flexible electrodes in the vertical direction; and S17, constructing a flexible electrode array according to the number of the flexible electrodes in the horizontal direction and the number of the flexible electrodes in the vertical direction, and loading the flexible electrode array on the mattress to obtain the physical sign monitoring mattress.
4. A method of flexible electrode array for non-contact vital sign monitoring according to claim 1, wherein said step S2 comprises the sub-steps of: step S201, a user to be tested lies on a physical sign monitoring mattress, and the physical sign monitoring mattress is utilized to monitor the electrocardiosignal measured by the user to be tested; Step S202, measuring an actual electrocardiosignal of a user to be measured, subtracting the actual electrocardiosignal from the measured electrocardiosignal and taking an absolute value to obtain an electrocardiosignal deviation value, and dividing the electrocardiosignal deviation value by the actual electrocardiosignal to obtain an electrocardiosignal deviation rate of the measured electrocardiosignal; Step S203, comparing the electrocardio deviation rate with a deviation rate threshold, if the electrocardio deviation rate is smaller than the deviation rate threshold, executing step S3, and if the electrocardio deviation rate is larger than or equal to the deviation rate threshold, executing step S204.
5. The method of claim 4, wherein the step S2 further comprises the sub-steps of: Step S204, regarding the process of generating electrocardiosignals from the heart until reaching the flexible electrode as a capacitive coupling equivalent circuit of the corresponding electrocardiosignals, recording the electrocardio potentials emitted by the heart, the dermis equivalent resistance of the dermis where the electrocardio potentials are located, the epidermis equivalent capacitance of the epidermis and the epidermis equivalent resistance; Step S205, calculating to obtain the total impedance of the human body based on the electrocardio potential, the dermis equivalent resistance, the epidermis equivalent capacitance and the epidermis equivalent resistance in the capacitive coupling equivalent circuit of the human body; In step S206, the electric field distribution corresponding to weak electrocardiosignals on the skin surface is equivalent to the electric charge surface density on the skin side, and when the flexible electrode is close to the skin, the electric field lines between the flexible electrode and the skin pass through the coupling layer to form electrostatic induction, so as to obtain an equivalent parallel plate capacitor formed by the skin-flexible electrode.
6. The method of claim 5, wherein the step S2 further comprises the sub-steps of: Step S207, recording the value of the electrocardio potential reaching the skin after the total impedance of the human body is reduced, wherein the electrocardio potential reaching the flexible electrode from the skin is subjected to secondary reduction, and the secondary reduction process is regarded as a parallel circuit of an equivalent parallel plate capacitor and a resistor, so as to obtain the coupling total impedance; Step S208, connecting the flexible electrode array with an amplifier, and recording the impedance of an input end as input impedance; Step S209, obtaining electrocardiosignals output by the amplifier according to the total impedance of the human body, the total coupling impedance and the input impedance.
7. The method of claim 6, wherein the step S2 further comprises the sub-steps of: Step S210, the step S207 is informed that if the output electrocardiosignal is close to the actually generated electrocardiosignal, the coupling total impedance can be adjusted only; Step S211, increasing the area of the flexible electrode array by adjusting the total coupling impedance; Step S212, adding flexible electrodes in the flexible electrode array step by step to increase the area of the flexible electrode array, measuring the added measurement electrocardiosignal again, calculating the corresponding electrocardio deviation rate until the electrocardio deviation rate is smaller than a deviation rate threshold value, storing the corresponding flexible electrode array and executing step S3; step S213, the detected measured electrocardiosignal is recorded as the electrocardiosignal data of the user to be detected.
8. A method of flexible electrode array for non-contact vital sign monitoring according to claim 1, wherein said step S3 comprises the sub-steps of: Step S301, when a physical sign monitoring mattress is unmanned, measuring a reference capacitance value of each flexible electrode in a flexible electrode array, marking the reference capacitance value on a graph according to the position of the flexible electrode, constructing a reference arrangement graph of the flexible electrode, constructing a plane rectangular coordinate system on the reference arrangement graph, and identifying to obtain the coordinate of each flexible electrode; Step S302, a user to be tested lies on the physical sign monitoring mattress in a lying mode, real-time capacitance values of each flexible electrode in the flexible electrode array are collected in real time, the time for collecting the real-time capacitance values for the first time is marked as first time, the time for collecting the real-time capacitance values for the second time is marked as second time, and the like, and the N time is marked; And step S303, marking the real-time capacitance value on the graph according to the position of the flexible electrode, and constructing a real-time arrangement graph of the flexible electrode at the corresponding moment.
9. The method of claim 7, wherein the step S3 further comprises the sub-steps of: Step S304, performing differential operation on the real-time alignment chart and the reference alignment chart at the first moment to obtain a flexible electrode capacitance difference chart at the first moment, wherein the ordinate of each flexible electrode in the flexible electrode capacitance difference chart is a capacitance difference value; step S305, counting the flexible electrodes with capacitance difference values larger than a preset value in the capacitance difference map of the corresponding flexible electrodes at the first moment as contact electrodes, and counting the number of the contact electrodes; step S306, adding, summing and averaging the coordinates of all the contact electrodes to obtain a barycenter coordinate, respectively leading a vertical line up and down according to the barycenter coordinate, dividing the contact electrodes into a left side and a right side, and calculating symmetry degrees of the left side and the right side; step S307, matching in a preset template based on the number of contact electrodes, the barycenter coordinates and the symmetry, and identifying to obtain an initial sleeping gesture corresponding to the user to be detected; And step 308, constructing a flexible electrode capacitance difference chart from the second moment to the N moment by using the process of the step 304, recording the moment when the real-time capacitance values of k flexible electrodes in the flexible electrode capacitance difference chart are suddenly changed as sleeping gesture change starting moment, and recording the moment when the capacitance difference values of k flexible electrodes in the flexible electrode capacitance difference chart become zero as sleeping gesture change ending moment.
10. The method of claim 9, wherein the step S3 further comprises the sub-steps of: Step S309, executing step S305-step S306 with a flexible electrode capacitance difference diagram at the sleeping gesture change ending moment to obtain the centroid coordinates, the number of contact electrodes and the symmetry degree at the sleeping gesture change ending moment; step S310, obtaining the sleeping gesture of the user to be tested at the sleeping gesture change end moment based on the centroid coordinates, the number of contact electrodes and the symmetry degree, and obtaining the turning direction of the user to be tested based on the movement condition of the centroid coordinates; step S311, the sleeping posture change corresponding to the user to be tested is recorded as sleeping posture data to be output.

Description

Flexible electrode array method for non-contact vital sign monitoring Technical Field The invention belongs to the technical field of biomedical engineering, and particularly relates to a flexible electrode array method for non-contact vital sign monitoring. Background Electrocardiogram is used as a golden standard detection tool for clinical diagnosis and evaluation of cardiovascular diseases, and abnormal signals indicate that the cardiovascular system of a human body has lesions with different degrees. However, the abnormal electrocardiosignals caused by cardiovascular lesions have sporadic, paroxysmal and transient characteristics, particularly in early stage of diseases, the occurrence frequency of the abnormal signals is extremely low, so that the early abnormal signals are difficult to be effectively captured by a short-time intermittent electrocardio monitoring technology, and therefore, the long-term continuous monitoring of the human electrocardiosignals is realized, and the method becomes a key technical support for early diagnosis and prevention of cardiovascular diseases. However, in the prior art, when vital signs are monitored, the traditional sensor is in direct contact with skin, so that the problem that the sleep of a user is disturbed due to excessive connecting wires of electrocardiograph monitoring equipment is easy to occur; therefore, the invention provides a flexible electrode array method for non-contact vital sign monitoring. Disclosure of Invention The invention aims to provide a non-contact type flexible electrode array method for vital sign monitoring, which aims to solve the problems in the background technology. In order to achieve the above purpose, the present invention adopts the following technical scheme: a flexible electrode array method of non-contact vital sign monitoring, the method comprising: Step S1, setting the layout of a flexible electrode array according to the human body size and the measurement range of the flexible electrode, and constructing a sign monitoring mattress based on the layout of the flexible electrode array; Step S2, analyzing the transmission flow of electrocardiosignals according to a capacitance sensing principle, judging the qualification of the flexible electrode array, and adjusting the unqualified flexible electrode array; Step S3, measuring capacitance data of the flexible electrode array of the user to be tested during sleeping, and identifying sleeping posture and sleeping posture change of the user to be tested based on the capacitance data; And S4, positioning and starting the flexible electrode array in a targeted manner to monitor by taking the sleeping posture of the user to be detected as a basis, and outputting sleeping posture data of the user to be detected and the electrocardiographic data obtained by measurement. Further, the step S1 includes the following sub-steps: Step S11, acquiring the human shoulder width range of an adult, and reading the upper limit value of the shoulder width of the human shoulder width range; step S12, setting the abduction occupation width and the unilateral turning allowance of an adult during sleeping; Step S13, obtaining the width of the electrode array by adding the upper limit value of the shoulder width and the natural abduction width and adding two times of unilateral turning allowance; Step S14, acquiring a trunk length range of an adult, and reading a trunk length upper limit value of the trunk length range; step S15, setting the sleep posture extension length, and obtaining the electrode array length by adding the upper limit value of the trunk length to the sleep posture extension length. Further, the step S1 further includes the following sub-steps: Step S16, reading a measuring range of the flexible electrode, and identifying a single-side measuring length of the corresponding flexible electrode, wherein the number of the flexible electrodes in the horizontal direction is obtained by dividing the width of the electrode array by the single-side measuring length, and the number of the flexible electrodes in the vertical direction is obtained by dividing the length of the electrode array by the single-side measuring length; obtaining the total number of the electrodes in the flexible electrode array by multiplying the number of the flexible electrodes in the horizontal direction by the number of the flexible electrodes in the vertical direction; and S17, constructing a flexible electrode array according to the number of the flexible electrodes in the horizontal direction and the number of the flexible electrodes in the vertical direction, and loading the flexible electrode array on the mattress to obtain the physical sign monitoring mattress. Further, the step S2 includes the following sub-steps: step S201, a user to be tested lies on a physical sign monitoring mattress, and the physical sign monitoring mattress is utilized to monitor the electrocardiosignal measured by the user to be te