A chest compression monitoring device, method and electronic equipment

Abstract

This application discloses a chest compression monitoring device, method, and electronic device, relating to the field of medical device technology. Specifically, the invention includes: a magnetic source module generating a magnetic field and acquiring a first magnetic field parameter; a magnetic sensing module acquiring a second magnetic field parameter; and a data processing module communicatively connected to each module. The data processing module compensates for the second magnetic field parameter based on the first magnetic field parameter and calculates the real-time distance and angle between the magnetic sensing module and the magnetic source module according to the compensated spatial component, thereby determining the compression depth along the target deformation direction. This application utilizes the first magnetic field parameter to compensate for the second magnetic field parameter in real time and calculates the real-time distance and angle between each magnetic sensor unit and the magnetic source module. This enables the sensing and compensation of geometric deviations caused by human body tilt, solving the problems of displacement misjudgment caused by non-rigid support surface concavity and geometric distortion in depth measurement caused by patient body tilt.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a chest compression monitoring device, method and electronic device. Background Technology

[0002] Chest compression monitoring devices are used in the field of emergency medicine. During cardiopulmonary resuscitation (CPR), they mainly monitor and provide data feedback on the depth, frequency, and chest recoil of the patient's chest in real time. This guides rescuers to control the pressure and rhythm of compressions, thereby ensuring the effectiveness and standardization of CPR procedures.

[0003] In existing technologies, cardiopulmonary resuscitation monitoring devices based on a single physical quantity for distance measurement are commonly used. For example, a device based on a single accelerometer measures the acceleration of the chest compression point and performs a second integral to obtain the displacement. This device is usually placed on the compression point on the patient's chest and calculates the depth of chest compressions by directly measuring the total displacement of the compression point in the vertical direction or by measuring the change in the straight-line distance between the compression point and the back.

[0004] However, the existing technologies mentioned above have the following shortcomings: In real emergency situations, patients are often placed on non-rigid support surfaces such as soft mattresses, stretchers, mountains, or slopes, and may also be placed on moving ambulances, helicopters, or ships. When rescuers perform chest compressions, the non-rigid support surface causes the patient's body to sink and tilt. Traditional monitoring devices cannot distinguish between the actual sinking of the chest itself and the overall body displacement caused by the indentation of the support surface. Therefore, the measured total displacement may incorrectly include parameters such as the thickness of the mattress indentation or the indentation of the ground, leading to a calculated result that is far greater than the actual chest compression depth, causing a serious overestimation problem and affecting the quality of emergency care. In addition, because the force on soft support surfaces is often uneven, the patient's body will tilt and deflect as the support surface sinks. Traditional monitoring devices can only measure a single straight-line distance like a ruler, assuming that the compression direction is always absolutely vertical; once the patient's body tilts due to the mattress indentation or the slope of the hillside, the actual direction of chest compression will also deflect. At this point, the traditional device was still measuring distance in a straight line according to the original incorrect direction, and could not detect the angle of body posture deviation, which caused the depth data, which was already overestimated due to the depression, to become even more severely distorted geometrically.

[0005] Therefore, this application aims to solve the problem that existing monitoring devices tend to misjudge the displacement of the support surface depression as the compression depth when facing a non-rigid support surface, resulting in inaccurate compression depth measurement. At the same time, it also solves the problem that the deformation of the non-rigid support surface causes the patient's body to tilt, resulting in the inability to detect the angle deflection in linear measurement and causing the depth measurement to be distorted. Summary of the Invention

[0006] The main purpose of this application is to provide a chest compression monitoring device, method and electronic device, which aims to solve the problem that the compression depth measurement is easily inaccurate on non-rigid support surfaces, and also to solve the problem that the patient's body is easily tilted on non-rigid support surfaces, causing the chest compression direction to deflect and resulting in the distortion of depth measurement.

[0007] To achieve the above objectives, this application proposes a chest compression monitoring device, comprising:

[0008] A magnetic source module is used to generate a magnetic field and acquire a first magnetic field parameter of the magnetic field; wherein, the magnetic source module includes a magnetic field generating unit disposed on the pressing part of the target and used to generate a magnetic field, and a reference magnetic sensing unit fixed in relative position to the magnetic field generating unit, the reference magnetic sensing unit being used to acquire the first magnetic field parameter.

[0009] A magnetic sensing module is used to acquire a second magnetic field parameter of the magnetic field.

[0010] The data processing module is communicatively connected to the magnetic source module and also to the magnetic sensing module; wherein,

[0011] The data processing module dynamically compensates the second magnetic field parameter based on the first magnetic field parameter, and calculates the real-time distance and real-time angle between the magnetic sensing module and the magnetic source module based on the spatial component of the compensated second magnetic field parameter, so as to extract the deformation component along the target deformation direction to determine the pressing depth.

[0012] Furthermore, the magnetic field generating unit includes:

[0013] An electromagnetic coil, used to generate a magnetic field;

[0014] The driving circuit has its output terminal electrically connected to the input terminal of the electromagnetic coil, and its input terminal connected to the power supply.

[0015] Furthermore, the cross-section of the electromagnetic coil is a flat conductor, and / or the electromagnetic coil has a Z-shaped folded winding structure.

[0016] Furthermore, the data processing module includes a dynamic compensation unit;

[0017] The first magnetic field parameter includes the total field strength. and preset reference distance ;

[0018] The dynamic compensation unit is used to adjust the total field strength of the first magnetic field parameter according to the dynamic compensation unit. and the preset reference distance The total field strength of the second magnetic field parameter Dynamic compensation is performed, and the formula for dynamic compensation is:

[0019] ;

[0020] This represents the real-time distance between the magnetic sensing module and the magnetic source module.

[0021] Furthermore, the data processing module also includes:

[0022] The signal acquisition unit is used to perform analog-to-digital conversion on the electrical signal output by the magnetic sensing module and extract the target frequency signal to obtain effective data of the second magnetic field parameter;

[0023] A unified calibration unit is used to correct the valid data in order to unify the global coordinate system;

[0024] The Z-axis determination unit is used to fit the normal vector of the thoracic plane to the spatial components of the magnetic sensing module in the global coordinate system, and to define the normal vector as the Z-axis direction of the target deformation direction.

[0025] Furthermore, the data processing module also includes:

[0026] An angle tracking unit is used to monitor the real-time angle between the magnetic sensing module and the Z-axis direction. And record the maximum included angle within each compression cycle. and its corresponding real-time distance .

[0027] Furthermore, the data processing module also includes:

[0028] The depth calculation unit calculates the pressure depth components of each magnetic sensing module and performs weighted fusion to determine the final pressure depth. The formula is as follows:

[0029] ;

[0030] in, and These are the initial reference distance and the initial reference angle before pressing; The pressing depth of the magnetic sensing module.

[0031] This application also discloses a feedback method for the above-mentioned chest compression monitoring device, including:

[0032] Acquire the first magnetic field parameters generated by the magnetic source module and the second magnetic field parameters generated by the magnetic sensing module;

[0033] Based on the first magnetic field parameters, the second magnetic field parameters are dynamically compensated and the real-time distance is calculated;

[0034] By using the spatial components of multiple magnetic sensing modules, the real-time distance and angle between the magnetic sensing module and the magnetic source module are calculated to determine the pressing depth along the target deformation direction.

[0035] This application also discloses an electronic device, including a memory and a processor, wherein the memory stores a computer program that can run on the processor, and the processor executes the program to implement the method described above.

[0036] The above technical solution has the following advantages:

[0037] This application utilizes a magnetic source module and a magnetic sensing module at the compression point to compensate for a second magnetic field parameter in real time using a first magnetic field parameter. It also calculates the real-time distance and angle between each magnetic sensor unit and the magnetic source module to determine the final true compression depth. Even when the patient is inside a moving ambulance, helicopter, ship, or other mobile device, interference from indentations on background support surfaces such as mattresses, stretchers, and slopes can be eliminated. Furthermore, by calculating the real-time distance and angle, it can sense and compensate for geometric deviations caused by body tilt, ensuring accurate measurement of the true chest compression depth even in complex positions. This effectively solves the problem of traditional accelerometer solutions being unable to distinguish between chest wall depression and indentations on non-rigid support surfaces (such as soft mattresses and stretchers), and also addresses the problem of depth measurement distortion caused by patient tilt on non-rigid support surfaces leading to chest compression direction deflection.

[0038] In the field of pre-hospital emergency care, this application enables accurate monitoring of various indices of chest compressions in sloping terrain or sloping support environments such as hillsides, mattresses, ambulances, helicopters, and ships, thereby improving the effectiveness and standardization of chest compressions. Attached Figure Description

[0039] The present application will now be described in detail with reference to specific embodiments and accompanying drawings, wherein:

[0040] Figure 1 This is a structural block diagram of an embodiment of this application;

[0041] Figure 2 This is a structural block diagram of another embodiment of this application;

[0042] Figure 3 This is a cross-sectional structural diagram of the magnetic source module of this application;

[0043] Figure 4 This is a schematic diagram of the Z-shaped folded winding structure of the electromagnetic coil of this application;

[0044] Figure 5 This is a structural block diagram of the method in this application.

[0045] In the diagram: 100, Data Processing Module; 101, Signal Acquisition Unit; 102, Unified Calibration Unit; 103, Dynamic Compensation Unit; 104, Z-Axis Determination Unit; 105, Angle Tracking Unit; 106, Depth Calculation Unit; 200, Magnetic Source Module; 201, Magnetic Field Generating Unit; 2011, Electromagnetic Coil; 2012, Drive Circuit; 202, Temperature Sensing Unit; 203, Reference Magnetic Sensing Unit; 300, Magnetic Sensing Module; 301, First Magnetic Sensing Unit; 302, Second Magnetic Sensing Unit; 303, Third Magnetic Sensing Unit; 304, Fourth Magnetic Sensing Unit; 400, Feedback Module; 401, Display Screen; 402, Light Bar Indicator. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the following specific embodiments are merely illustrative of this application and do not constitute a limitation thereof.

[0047] In cardiopulmonary resuscitation (CPR), the quality of chest compressions is crucial to the success rate of resuscitation. Clinical guidelines clearly require that the compression depth for adults be maintained at 5-6 cm, the compression rate at 100-120 compressions per minute, and that the chest wall fully recoil during the intervals between compressions. However, existing monitoring devices based on a single accelerometer have shortcomings in practical applications. Specifically, the working principle of an accelerometer is mainly to calculate displacement by the double integration of the acceleration signal, but in real emergency situations, patients are often located on ambulance stretchers, soft mattresses, or mobile carts. When the rescuer applies pressure, the non-rigid support surface undergoes elastic deformation. Because the accelerometer cannot distinguish between the downward displacement of the chest wall itself and the overall displacement caused by the indentation of the support surface, the measured depth often exceeds the amount of mattress compression, resulting in an overestimation of the measurement result. Furthermore, during chest compressions, the rescuer's uneven pressure often causes the body to tilt or deflect to the side. Existing linear distance measuring devices assume that the compression direction is absolutely vertical when detecting this, and cannot detect the geometric distortion caused by body position deflection.

[0048] Based on the above-mentioned technical problems, this application proposes a chest compression detection device, method and electronic device by utilizing the attenuation characteristics of magnetic fields in space.

[0049] The following is an explanation of the terms used in this application:

[0050] Target deformation direction: refers to the actual axis of the chest wall deformation under compression during cardiopulmonary resuscitation. In this embodiment, this direction is defined as the anteroposterior diameter of the human chest wall, that is, the Z-axis direction perpendicular to the plane of the human sternum.

[0051] The first magnetic field parameter and the second magnetic field parameter: The first magnetic field parameter refers to the known reference magnetic field vector data generated by the magnetic source module 200 at the reference point, which is used for self-calibration inside the monitoring device; the second magnetic field parameter refers to the real-time magnetic field vector data captured by the magnetic sensing module 300 distributed on the human body surface, which is used to calculate spatial coordinates.

[0052] Spatial component: refers to the magnetic induction intensity values ​​output by the magnetic sensor on the three mutually perpendicular coordinate axes X, Y, and Z.

[0053] Unified calibration unit 102: refers to an initialization process that automatically solves the installation deviation of the magnetic sensor by acquiring the standard alternating magnetic field of the magnetic source module 200 before pressing begins, using the least squares method, so that the operator can attach the magnetic sensor at any angle without affecting the measurement accuracy.

[0054] like Figure 1 and Figure 2 As shown, this embodiment provides a chest compression monitoring device based on magnetic ranging. The chest compression monitoring device in this embodiment includes a magnetic source module 200, a magnetic sensing module 300, and a data processing module 100. The magnetic source module 200 is used to generate a magnetic field and acquire a first magnetic field parameter of the magnetic field; the magnetic sensing module 300 is used to acquire a second magnetic field parameter of the magnetic field; the data processing module 100 is communicatively connected to the magnetic source module 200 and also communicatively connected to the magnetic sensing module 300.

[0055] The data processing module 100 compensates the second magnetic field parameter based on the first magnetic field parameter, and calculates the real-time distance and real-time angle between the magnetic sensing module 300 and the magnetic source module 200 based on the spatial component of the compensated second magnetic field parameter, so as to determine the pressing depth along the target deformation direction.

[0056] In some embodiments, the magnetic source module 200 is disposed on the chest compression point of the human body, that is, the sternal surface at the midpoint of the line connecting the two nipples. The magnetic source module 200 is used to generate the required magnetic field at the chest compression point of the human body. At the same time, the magnetic source module 200 can also acquire the first magnetic field parameter of the magnetic field. The first magnetic field parameter is used as internal reference data and is used to detect the magnetic field state generated by the magnetic source module 200.

[0057] The magnetic sensing module 300 includes at least one magnetic sensing unit. If multiple magnetic sensing units are used, they are distributed at different reference locations on the human body surface, such as the posterior midline of the back at the nipple level (corresponding to the area directly behind the chest pressure point), the shoulder, and the armpit. The number of magnetic sensing units is adjusted according to the location of the body. Specifically, if it is necessary to monitor magnetic field data at the posterior midline of the back at the nipple level, the left shoulder, the left posterior axillary line at the nipple level, and the right mid-axillary line at the nipple level, the magnetic sensing module 300 can include four magnetic sensing units, such as... Figure 2 The first magnetic sensing unit 301, the second magnetic sensing unit 302, the third magnetic sensing unit 303, and the fourth magnetic sensing unit 304 shown are applied to the corresponding positions on the human body and detect the magnetic field status of the chest compression points received at different positions in real time to generate the second magnetic field parameters.

[0058] The data processing module 100 is communicatively connected to the magnetic source module 200 and the magnetic sensing module 300. Specifically, the connection can be made via a high-speed communication bus or via wireless communication, such as Bluetooth or Wi-Fi. In this application, the data processing module 100 can be implemented using a microcontroller (MCU), FPGA (Field Programmable Gate Array), PLC (Programmable Logic Controller), DSP (Digital Signal Processor), or SOC (System on Chip). In this embodiment, the data processing module 100 can be a single-chip microcomputer, such as the STM32 series.

[0059] The data processing module 100 is used to perform orientation correction on the second magnetic field parameters, uniformly map the spatial components acquired by each magnetic sensing unit to the global coordinate system; fit the normal vector of the patient's chest plane according to the spatial components mapped to the global coordinate system, and lock the normal vector as the Z-axis direction of the target deformation direction; dynamically compensate the second magnetic field parameters based on the first magnetic field parameters, and calculate the real-time distance of each magnetic sensing unit relative to the magnetic source module 200; calculate and extract the deformation component along the Z-axis direction according to the real-time angle of each magnetic sensing unit relative to the Z-axis direction and the real-time distance, so as to determine the actual compression depth.

[0060] The data processing module 100 uses the first magnetic field parameter to perform gain and zero-bias compensation on the second magnetic field parameter, thereby eliminating interference caused by driving current fluctuations or environmental electromagnetic noise. In other words, the monitoring device not only acquires the second magnetic field parameter at different reference positions on the human body surface, but also calculates the real-time distance and angle between the magnetic sensing module 300 and the magnetic source module 200 by performing geometric analysis on the spatial components of the compensated magnetic field vector. The data processing module 100 then uses the real-time distance and real-time angle to determine the pressing depth along the target deformation direction.

[0061] In this embodiment, by calculating the relative motion between the magnetic sensing module 300 and the magnetic source module 200, the ranging reference is established on the relative displacement between the magnetic source module 200 and the magnetic sensing module 300. Even if the patient is in a moving ambulance, the interference from the depression of the background support surface such as the mattress and stretcher can be eliminated. Furthermore, by calculating the real-time distance and real-time angle, the geometric deviation caused by the tilt of the human body can be sensed and compensated, ensuring that the true chest compression depth can be accurately measured even in complex positions.

[0062] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the magnetic source module 200 includes a magnetic field generating unit 201 and a reference magnetic sensing unit 203. The magnetic field generating unit 201 is disposed at the pressing part of the target and is used to generate the magnetic field. The relative position of the reference magnetic sensing unit and the magnetic field generating unit 201 is fixed and is used to obtain the first magnetic field parameters.

[0063] In some embodiments, the magnetic field generating unit 201 is disposed at the pressure point of the human body to generate the required stable magnetic field;

[0064] The reference magnetic sensing unit 203 is fixed to the edge of the electromagnetic coil 2011. The relative displacement between the two is solidified during the production stage. The reference magnetic sensing unit 203 and the magnetic field generating unit 201 can be integrated into the pressing pad, and the reference magnetic sensing unit 203 is set 5mm to 10mm away from the edge of the magnetic field generating unit 201. In order to ensure that the response characteristics of the first magnetic field parameter and the second magnetic field parameter are completely matched, it is preferable that the reference magnetic sensing unit 203 and the magnetic sensing module 300 use the same type of sensor, such as a triaxial tunnel magnetoresistance (TMR) sensor.

[0065] Specifically, the reference magnetic sensing unit 203 captures the first magnetic field parameters in real time. Since the magnetic source module 200 generates heat during continuous operation, the coil resistance of the magnetic field generating unit 201 changes, which in turn causes fluctuations in the driving current. The real-time first magnetic field parameters measured by the reference magnetic sensing unit 203 can be used as a reference quantity. The data processing module 100 can obtain the output energy level of the magnetic source module 200 in real time through the reference magnetic sensing unit 203, providing real-time calibration for all subsequent magnetic sensing units distributed around the human body.

[0066] like Figure 2 and Figure 4 As shown, in one embodiment of this application, the magnetic field generating unit 201 is specifically composed of an electromagnetic coil 2011 and a driving circuit 2012. The electromagnetic coil 2011 is used to generate a magnetic field, and the output terminal of the driving circuit 2012 is electrically connected to the input terminal of the electromagnetic coil 2011, and its input terminal is connected to a power supply.

[0067] In some embodiments, the electromagnetic coil 2011 has a multi-layered folded structure. When the electromagnetic coil 2011 is energized, it can convert electrical energy into magnetic energy (i.e., generate a magnetic field). Magnetic sensing units distributed at different locations on the human body acquire corresponding second magnetic field parameters in the magnetic field and send the second magnetic field parameters to the data processing module 100. The data processing module 100 uses the first magnetic field parameters as a reference and performs compensation, calculation, and other steps on the second magnetic field parameters to finally obtain the pressure depth of the target deformation, which is used to provide feedback on the pressure status of the person on the patient, thereby improving the person's pressure method.

[0068] The input terminal of the drive circuit 2012 is connected to a power supply line, such as a 3.7V lithium-ion battery pack, or an external power supply line via a transformer. Specifically, the drive circuit 2012 incorporates a DC-DC boost converter and a pulse width modulation (PWM) modulator, boosting the voltage to 12V to generate high-energy magnetic pulses. In this embodiment, the drive circuit 2012 controls the coil to generate an alternating magnetic field with a frequency of 5kHz. This 5kHz alternating magnetic field is designed to avoid the absorption of high-frequency electromagnetic waves by human tissue, and also to avoid 50Hz power frequency electromagnetic interference. Through pulse width modulation technology, the drive circuit 2012 keeps the average current below 50mA and the average power consumption at only 0.6W. This extremely low power consumption design suppresses heat generation in the monitoring device, ensuring safety during prolonged contact between the pressure pad and the patient's skin.

[0069] like Figures 2 to 4 As shown, in one embodiment of this application, the cross-section of the electromagnetic coil 2011 is a flat wire, and / or the electromagnetic coil 2011 has a Z-shaped folded winding structure.

[0070] In some embodiments, the electromagnetic coil 2011 employs a flattening process. Preferably, the electromagnetic coil 2011 is made of copper, and more preferably, the electromagnetic coil 2011 is composed of multiple layers of Z-shaped folded flat copper wires stacked together. The thickness of the flattened copper wires is 0.1 mm, and the width is 1.2 mm. Figure 3 As can be seen from the flat structure, the layers are separated by a 0.02mm thick polyimide insulating film. The Z-shaped folding winding mentioned in this application refers to the flat conductor being wound from the center outwards in the first layer, reaching the outer loop, and then folded vertically downwards through a Z-shaped structure to the second layer. The second layer is then wound from the outside inwards, and so on. Figure 4 As can be seen from the winding structure, this embodiment achieves a 12-layer stacked structure in a 70mm×70mm plane, and this structure achieves a high-density winding of 264 turns in a space with a thickness of only 1.2mm.

[0071] This embodiment maximizes the number of coil turns without increasing the thickness, and the flat coil has an extremely high lateral thermal conductivity, which can quickly dissipate the heat generated during operation laterally. At the same time, when the rescuer is performing CPR, the extremely thin flat coil makes the tactile sensation between the palm and the patient's sternum more obvious, and the rescuer's pressure sensation is also more obvious, improving the rescuer's perception.

[0072] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the data processing module 100 includes a dynamic compensation unit 103;

[0073] The first magnetic field parameter includes the total field strength. and preset reference distance ;

[0074] The dynamic compensation unit 103 is used to calculate the total field strength of the first magnetic field parameter. and the preset reference distance The total field strength of the second magnetic field parameter Dynamic compensation is performed, and the formula for dynamic compensation is:

[0075] ;

[0076] This refers to the real-time distance between the magnetic sensing module 300 and the magnetic source module 200.

[0077] In some embodiments, the data processing module 100 performs nonlinear calculations through the dynamic compensation unit 103, and the first magnetic field parameter includes the total field strength measured by the reference magnetic sensing unit 203. and the reference distance pre-stored in non-volatile memory In this embodiment, a reference distance can be selected. The diameter is 40.5 mm. The dynamic compensation unit 103 utilizes a physical model of magnetic field strength decreasing with the cube of distance, and executes the following formula:

[0078] ;

[0079] The above formula calculates the total field strength of the first magnetic field parameter. The total field strength of the second magnetic field parameter in real time The ratio of the magnetic sensing units and the cube root are used to calculate the real-time distance between the magnetic sensing units and the magnetic source module 200. Specifically, in this embodiment, four magnetic sensing units are used: the first magnetic sensing unit 301, the second magnetic sensing unit 302, the third magnetic sensing unit 303, and the fourth magnetic sensing unit 304. The real-time distances between the corresponding magnetic sensing units and the magnetic source module 200 are calculated sequentially. .

[0080] In other words, fluctuations in the intensity of the magnetic source module 200 are reflected in both the numerator and denominator. By taking the cube root, these fluctuations cancel each other out. This physical model not only eliminates signal gain fluctuations but also removes interference from static magnetic field backgrounds in space through a ratio algorithm, achieving highly robust ranging performance. Even in complex electromagnetic environments, it can output stable absolute distance values.

[0081] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the data processing module 100 further includes a signal acquisition unit 101, a unified calibration unit 102, and a Z-axis determination unit 104;

[0082] The signal acquisition unit 101 is used to perform analog-to-digital conversion on the electrical signal output by the magnetic sensing module 300 and extract the target frequency signal to obtain effective data of the second magnetic field parameter; the unified calibration unit 102 is used to correct the effective data to unify the global coordinate system; the Z-axis determination unit 104 is used to fit the normal vector of the thoracic plane through the spatial components of the magnetic sensing module 300 in the global coordinate system, and define the normal vector as the Z-axis direction of the target deformation direction.

[0083] In some embodiments, the signal acquisition unit 101 uses the built-in ADC of the STM32 series microcontroller to perform analog-to-digital conversion on the analog electrical signal at a frequency of 200Hz, and uses lock-in amplification technology to accurately extract the target frequency signal (i.e., alternating magnetic field) of 5kHz, thereby ensuring that 200 sets of effective magnetic field vectors can be captured per second; wherein, the target frequency signal can be selected as needed, or the target frequency signal of 8kHz or 10kHz can be extracted, there is no specific limitation here; the signal acquisition unit 101 obtains the effective data of the second magnetic field parameter through the target frequency signal.

[0084] Before the pressing begins, the unified calibration unit 102 uses the 1-second target frequency signal generated by the magnetic source module 200 to preferably calculate the rotation matrix of each magnetic sensing unit using the least squares method. and zero bias vector The raw data of each magnetic sensing unit is mapped to a global coordinate system with the center of the sternum as the origin, such as the coordinate system with the X-axis pointing to the right, the Y-axis pointing to the head, and the Z-axis pointing forward.

[0085] Furthermore, the device incorporates a unified on-site calibration function, which automatically calibrates the orientation and zero point of all 300 magnetic sensing modules before each use. Clinical operators only need to attach each magnetic sensing unit to its correct position without needing to specifically check the alignment of the units. Specifically, the calibration principle and steps of the unified calibration unit are as follows:

[0086] Step 1: The magnetic source module 200 generates a standard alternating magnetic field and continues it for a preset time (e.g., 1 second).

[0087] Step 2: All magnetic sensing units (including reference magnetic sensing unit 203) synchronously acquire data at a preset frequency (e.g., 200Hz).

[0088] Step 3: According to the magnetic dipole model, the measured value of each magnetic sensing unit satisfies the following formula:

[0089] ;

[0090] This represents the actual measured value of the i-th magnetic sensing unit; This represents the theoretical magnetic field generated by a known magnetic source module; This represents the design location of the i-th magnetic sensing unit.

[0091] Step 4: Solve for the rotation matrix of each magnetic sensing unit using the overall least squares method. and zero bias vector .

[0092] Step 5: Apply the rotation matrix obtained above. and zero bias vector The data is stored and then used for real-time calibration during the pressing process. The specific formula is as follows:

[0093] ;

[0094] It removes the application angle error and unifies the true spatial components (spatial coordinates) under the global coordinate system. It includes the spatial components of multiple magnetic sensing units and can be used by the dynamic compensation unit 103 to calculate the real-time distance between the magnetic sensing unit and the magnetic source module 200.

[0095] Through the above calculations of the unified calibration unit 102, the magnetic sensing unit attachment deviation in any direction can be effectively corrected. Theoretically, even if there is a large deviation between the magnetic sensing unit plane and the ideal plane (such as a vertical 90° deviation), the device can still accurately complete the calibration and unify it into the global coordinate system.

[0096] The Z-axis determination unit 104 calculates the instantaneous geometric plane of the human thoracic cavity using a three-dimensional simulation algorithm based on the spatial components of the first magnetic sensing unit 301, the second magnetic sensing unit 302, the third magnetic sensing unit 303, and the fourth magnetic sensing unit 304 in the global coordinate system (after the second magnetic field parameters of the dynamic compensation unit 103). Specifically, the monitoring device takes the normal vector of the instantaneous geometric plane as the true compression direction, defined as the Z-axis direction. Even if the patient is in a lateral decubitus position or on an inclined stretcher, the monitoring device can automatically find and lock the true deformation axis, avoiding the measurement failure caused by relying solely on linear displacement gauges in existing methods when the patient's angle deflects.

[0097] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the data processing module 100 further includes:

[0098] Angle tracking unit 105 is used to monitor the real-time angle between the magnetic sensing module 300 and the Z-axis direction. And record the maximum included angle within each compression cycle. and its corresponding real-time distance .

[0099] In some embodiments, the angle tracking unit 105 is responsible for monitoring geometric variables during the dynamic process. During the pressing and downward movement, the connection direction of the magnetic source module 200 relative to the magnetic sensing unit will continuously change, and the device monitors in real time the angle between each magnetic sensing module 300 and the fitted Z-axis direction. During each pressing cycle, the angle tracking unit 105 records the maximum included angle during the pressing process. and the real-time distance at the deepest point. In other words, the device not only monitors the real-time distance but also the corresponding angle simultaneously. The angle tracking unit 105 can capture the instantaneous shift caused by uneven pressure on the chest during compression, thereby completely reconstructing the compression trajectory in three-dimensional space and providing precise angle compensation parameters for subsequent projection calculations.

[0100] like Figure 1 and Figure 2 As shown, in one embodiment of this application, the data processing module 100 further includes:

[0101] The depth calculation unit 106 is used to calculate the pressure depth components of each magnetic sensing module 300 and perform weighted fusion to determine the final pressure depth. The formula is as follows:

[0102] ;

[0103] in, and These are the initial reference distance and the initial reference angle before pressing; This refers to the pressing depth of the magnetic sensing module 300.

[0104] In some embodiments, the depth calculation unit 106 employs a spatial geometric difference algorithm, the formula of which is: .in, and This is the initial reference value collected when the device is stationary after startup. Specifically, this formula represents the distance vector in space. The vector is projected onto the Z-axis of the normal vector, and its effective component along the deformation axis is extracted. The final compression depth is determined by weighted fusion, for example, the back magnetic sensing unit is assigned a weight of 0.5, and the other positions are assigned weights of approximately 0.15 to 0.175. The back magnetic sensing unit is used as the main reference point, and the other lateral magnetic sensing units are used as correction points. Together, they cancel out the lateral sliding noise caused by the rescuer's improper operation, and control the final measurement error within 1.0 mm.

[0105] In this embodiment, one implementation method is given, and the weighted fusion ratio is as follows: the back magnetic sensing unit accounts for 0.5, the left shoulder magnetic sensing unit accounts for 0.15, and the two armpit magnetic sensing units each account for 0.175.

[0106] Initial calibration state: After the device is started, 2 seconds of static data are continuously collected as a reference.

[0107] Taking the first magnetic sensing unit 301 as an example, the initial reference distance Initial angle .

[0108] Taking the second magnetic sensing unit 302 as an example, the initial reference distance Initial angle .

[0109] Taking the third magnetic sensing unit 303 as an example, the initial reference distance Initial angle .

[0110] Taking the fourth magnetic sensing unit 304 as an example, the initial reference distance Initial angle .

[0111] Real-time press status: When the press reaches its deepest point.

[0112] The first magnetic sensing unit 301 real-time distance Real-time angle .

[0113] The second magnetic sensing unit 302 real-time distance Real-time angle .

[0114] The third magnetic sensing unit 303 provides real-time distance. Real-time angle .

[0115] The fourth magnetic sensing unit 304 real-time distance Real-time angle .

[0116] Component calculation:

[0117] ;

[0118] ;

[0119] ;

[0120] ;

[0121] Final Fusion:

[0122] .

[0123] All measurement components are unified to the Z-axis through spatial geometric mapping. In other words, even if the second magnetic sensing unit 302 (shoulder position) undergoes a large angle change during pressing, the device can extract the depth corresponding to that position through cosine compensation and compress the overall pressing error to within 1.5mm.

[0124] In one embodiment of this application, the data detection module may further include a sensor detection module. The sensor detection module is connected to the corresponding first magnetic sensing unit 301, second magnetic sensing unit 302, third magnetic sensing unit 303, fourth magnetic sensing unit 304 and reference magnetic sensing unit 203 respectively. If the first magnetic sensing unit 301 is damaged, the data processing module 100 will automatically remove the abnormal sensor and use the remaining magnetic sensing units to perform calculations in order to maintain accuracy.

[0125] like Figure 2 As shown, in one embodiment of this application, the monitoring device also includes a feedback module 400. The feedback module 400 is used to provide real-time feedback on the compression quality of the personnel. The feedback module 400 is electrically connected to the data processing module 100. The feedback unit includes a display screen 401, a light bar indicator 402, etc. The display screen 401 is used to display the current compression depth value, frequency, CCF, and other indicators in real time. The light bar indicator 402 is composed of multi-color LED light bars. When the compression depth is within the standard range of 5cm to 6cm, it displays green; when the depth is insufficient, it displays yellow; and when the depth is excessive, it displays red. The feedback module 400 is used to remind the personnel of the compression status and facilitate the personnel to make corresponding adjustments after checking. The indicators of the light bar and the display screen 401 can be adjusted and modified accordingly. Specifically, depending on different usage scenarios, the corresponding light bar indicator 402 can be added, modified, or reduced, and the specific parameters on the display screen 401 can also be modified.

[0126] like Figure 2 As shown in one embodiment of this application, the magnetic source module 200 further includes a temperature sensing unit 202, which is used to monitor the temperature of the electromagnetic coil 2011 in real time. When the temperature of the electromagnetic coil 2011 exceeds 45°C, the device automatically switches to a frequency reduction intermittent working mode: the sampling frequency is reduced to 100Hz, the coil is activated for 5ms at each sampling point, the duty cycle is 50%, and the average power consumption is reduced by 50%. The specific temperature protection scheme is as follows:

[0127] Table 1. Operating modes of electromagnetic coil 2011 as a function of temperature.

[0128]

[0129] As shown in Table 1, the data processing module 100 will execute different working modes according to the temperature of the electromagnetic coil 2011. When the temperature of the electromagnetic coil 2011 is below 45℃, the signal sampling unit will maintain the original sampling frequency and duty cycle. When the temperature is between 40℃ and 45℃, the feedback module 400 will display corresponding warning information, such as a yellow warning light. When the temperature is between 45℃ and 50℃, the signal sampling unit will reduce the overall sampling frequency, which will be implemented through the duty cycle. The feedback module 400 will then display corresponding warning information, such as an orange-yellow warning light. When the temperature exceeds 50℃, the signal sampling unit will stop detecting. At this time, the feedback module 400 will display corresponding warning information, such as a red warning light. A buzzer may also be used. The power supply to the electromagnetic coil 2011 should also be turned off, indicating that the electromagnetic coil 2011 has exceeded its rated operating temperature.

[0130] like Figure 5 As shown, this application also discloses a feedback method for the above-mentioned chest compression monitoring device, comprising:

[0131] Step S1: Obtain the first magnetic field parameters generated by the magnetic source module 200 and the second magnetic field parameters generated by the magnetic sensing module 300;

[0132] Step S2: Dynamically compensate the second magnetic field parameters based on the first magnetic field parameters and calculate the real-time distance;

[0133] Step S3: Calculate the real-time distance and angle between the magnetic sensing module 300 and the magnetic source module 200 using the spatial components of multiple magnetic sensing modules 300, in order to determine the pressing depth along the target deformation direction.

[0134] Specifically, step S1 mainly controls the magnetic source module 200 to generate an alternating magnetic field and acquire the first magnetic field parameter, and acquires the second magnetic field parameter through multiple magnetic sensing units distributed on the body surface. The magnetic source module 200 is placed at the patient's sternal compression point, and the magnetic sensing module 300 is applied to the patient's back and lateral chest wall. The driving circuit 2012 drives the electromagnetic coil 2011 to generate a 5kHz alternating magnetic field. The first magnetic field parameter of the alternating magnetic field is acquired by the reference magnetic sensing unit 203. The first magnetic sensing unit 301, the second magnetic sensing unit 302, the third magnetic sensing unit 303, and the fourth magnetic sensing unit 304 are used to acquire multiple second magnetic field parameters.

[0135] Step S2 is mainly used to correct the spatial components in the second magnetic field parameters, uniformly mapping the spatial components of each magnetic sensing unit to the global coordinate system; and fitting the normal vector of the thoracic plane based on the spatial components mapped to the global coordinate system, locking it as the Z-axis direction of the target deformation direction. Specifically, after the signal acquisition unit 101 extracts the signals from each magnetic sensing unit, the unified calibration unit 102 automatically acquires the target frequency signal using the least squares method before pressing, calculates the rotation matrix and zero bias vector of each magnetic sensing unit, and uniformly maps the originally chaotic directions of all magnetic sensing units to the global coordinate system with the sternum as the origin, obtaining the calibrated spatial components; subsequently, the dynamic compensation unit 103 uses the first magnetic field parameters acquired in real time by the reference magnetic sensing unit to compensate for the second magnetic field parameters acquired by the magnetic sensing module, calculating the accurate initial reference distance after eliminating environmental interference. Z-axis determination unit 104 combines the calibrated spatial components with the compensated precise reference distance. The precise spatial coordinates of each magnetic sensing unit are calculated to fit the normal vector of the patient's current thoracic plane (locking the true deformation Z-axis), and the initial reference distance is recorded. Angle with the initial reference .

[0136] Step S3 primarily involves real-time dynamic compensation of the second magnetic field parameter based on the first magnetic field parameter, calculating the real-time distance of each magnetic sensing unit; simultaneously monitoring the real-time angle of each magnetic sensing unit relative to the Z-axis direction, extracting the effective deformation component along the Z-axis direction to determine the final true compression depth. Specifically, when the rescuer begins applying compressions, the dynamic compensation unit 103 continuously uses the first magnetic field parameter to perform real-time compensation of the second magnetic field parameter, calculating the real-time absolute distance, while the angle tracking unit 105 records the real-time angle of each magnetic sensing unit relative to the Z-axis at this time. Subsequently, the depth calculation unit 106 utilizes the spatial geometric difference algorithm, through the formula... After eliminating errors caused by the patient's overall body tilt or slippage, the effective deformation component along the Z-axis (anteroposterior diameter of the thoracic cavity) is extracted. The depth calculation unit 106 performs weighted fusion of each component (for example, the back is weighted at 0.5, the shoulder at 0.15, and the armpit at 0.175) to obtain the final true compression depth.

[0137] In other words, whether the patient is on the swaying chassis of an ambulance or on an extremely soft home mattress, this method can provide the rescuer with the most realistic feedback on the depth of compression by dynamically compensating for interference from the stripped support surface in real time.

[0138] In one embodiment of this application, an electronic device is also disclosed, including a memory and a processor. The memory stores a computer program that can run on the processor, and the processor executes the program to implement the method described above.

[0139] In this embodiment, the processor's control core uses an STM32 microcontroller with a main frequency of over 168MHz and a built-in 12-bit ADC. Specifically, the device provides feedback to the rescuer through a feedback unit (including a display screen 401 and a light bar indicator 402), which can accurately display the current depth, frequency, CCF, and chest recoil in real time.

[0140] In another embodiment of this application, an alternative based on a permanent magnet is provided for the magnetic field generating unit 201. Specifically, a neodymium iron boron (NdFeB) permanent magnet with a thickness of 1.0 mm to 1.5 mm with high remanence is used to replace the electromagnetic coil 2011. In this static magnetic field scheme, the driving circuit 2012 is omitted, and the data processing module 100 captures the gradient changes of the static magnetic field. To compensate for geomagnetic field and environmental interference, the reference magnetic sensing unit 203 first collects the background static magnetic field of the environment and performs real-time subtraction. The magnetic source unit of this embodiment does not require battery power, which greatly extends the overall battery life, and the reference pad can be made thinner and lighter, with a total thickness of less than 1.8 mm, making it particularly suitable for restricted environments such as long-distance field transport and emergency rescue.

[0141] In actual cardiopulmonary resuscitation (CPR) emergency scenarios, the process by which the chest compression monitoring device of this application acquires and calculates the overall compression depth is as follows:

[0142] first step:

[0143] The rescuer places the magnetic source module 200, which includes the electromagnetic coil 2011, at the patient's sternal compression point, and randomly applies the magnetic sensing module 300 (including the first magnetic sensing unit 301, the second magnetic sensing unit 302, the third magnetic sensing unit 303, and the fourth magnetic sensing unit 304) to the patient's back and lateral chest wall.

[0144] After the device is powered on, the drive circuit 2012 drives the electromagnetic coil 2011 to generate a 5kHz alternating magnetic field. After the signal acquisition unit 101 extracts the signals from each magnetic sensing unit, the unified calibration unit 102 automatically performs approximately 1 second of target frequency signal acquisition using the least squares method before pressing, and calculates the rotation matrix of each magnetic sensing unit. and zero bias vector The originally chaotic orientations of all magnetic sensing units are uniformly mapped to a global coordinate system with the sternum as the origin.

[0145] Step Two:

[0146] In the static state before pressing begins, data is continuously collected for 2 seconds. The dynamic compensation unit 103 uses the first magnetic field parameter to compensate for the second magnetic field parameter, obtaining the initial reference distance of each magnetic sensing unit after interference removal. The Z-axis determining unit 104 combines the spatial components in a unified coordinate system with the aforementioned precise initial distance. The accurate coordinates of each magnetic sensing unit in three-dimensional space are calculated, and the normal vector of the patient's current thoracic plane is fitted accordingly to lock the true deformation Z-axis. Simultaneously, the initial reference distance of each magnetic sensing unit relative to the magnetic source module is recorded. Angle with the initial reference .

[0147] Step 3:

[0148] When the rescuer begins to apply chest compressions, the patient's chest will sink and the supporting surface (such as a soft mattress) may deform. At this time, the electromagnetic coil 2011 may cause fluctuations in magnetic field strength due to heat generation. The reference magnetic sensing unit 203 acquires the current first magnetic field parameter in real time and uses the first magnetic field parameter as a reference.

[0149] The dynamic compensation unit 103 uses the first magnetic field parameter to perform real-time compensation on the second magnetic field parameter collected by the magnetic sensing module 300, and calculates the real-time distance after eliminating environmental and heat interference. Meanwhile, the angle tracking unit 105 monitors the real-time angles between each magnetic sensing unit and the Z-axis. .

[0150] Step 4:

[0151] When the deepest point of a single press is reached, the angle tracking unit 105 records the maximum included angle of each magnetic sensing unit at that moment. and the corresponding real-time distance The depth computing unit 106 utilizes a spatial geometric difference algorithm, through the formula... To eliminate errors caused by the overall tilting or slippage of the patient's body, the effective deformation component along the Z-axis (anteroposterior diameter of the thoracic cavity) is extracted.

[0152] Step 5:

[0153] Since the back sensor best reflects the pressure on the chest, the depth calculation unit 106 performs weighted fusion of each component (for example, the back is weighted at 0.5, the shoulder at 0.15, and the armpit at 0.175) to obtain the final true compression depth.

[0154] Step 6:

[0155] The data processing module 100 sends the actual compression depth to the feedback module 400, which displays the specific value on the display screen 401 and uses the color (green, yellow, red) of the light bar indicator 402 to intuitively indicate to the rescuer whether the compression pressure is up to standard. Thus, a precise closed-loop monitoring of compression depth is completed.

[0156] The above description is merely a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the inventive concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A chest compression monitoring device, characterized in that, include: A magnetic source module is used to generate a magnetic field and acquire a first magnetic field parameter of the magnetic field; wherein, the magnetic source module includes a magnetic field generating unit disposed on the pressing part of the target and used to generate a magnetic field, and a reference magnetic sensing unit fixed at a relative position to the magnetic field generating unit, the reference magnetic sensing unit being used to acquire the first magnetic field parameter. A magnetic sensing module is used to acquire a second magnetic field parameter of the magnetic field. The data processing module is communicatively connected to the magnetic source module and also communicatively connected to the magnetic sensing module; the data processing module further includes: The signal acquisition unit is used to perform analog-to-digital conversion on the electrical signal output by the magnetic sensing module and extract the target frequency signal to obtain effective data of the second magnetic field parameter; A unified calibration unit is used to correct the valid data in order to unify the global coordinate system; The Z-axis determination unit is used to fit the normal vector of the thoracic plane to the spatial components of the magnetic sensing module in the global coordinate system, and to define the normal vector as the Z-axis direction of the target deformation direction. An angle tracking unit is used to monitor the real-time angle between the magnetic sensing module and the Z-axis direction. And record the maximum included angle within each compression cycle. and its corresponding real-time distance ; The depth calculation unit calculates the pressure depth components of each magnetic sensing module and performs weighted fusion to determine the final pressure depth. The formula is as follows: ； in, and These are the initial reference distance and the initial reference angle before pressing; The pressing depth of the magnetic sensing module; The data processing module dynamically compensates the second magnetic field parameter based on the first magnetic field parameter, and calculates the real-time distance and real-time angle between the magnetic sensing module and the magnetic source module based on the spatial component of the compensated second magnetic field parameter, so as to extract the deformation component along the target deformation direction to determine the pressing depth.

2. The chest compression monitoring device as described in claim 1, characterized in that, The magnetic field generating unit includes: An electromagnetic coil, used to generate a magnetic field; The driving circuit has its output terminal electrically connected to the input terminal of the electromagnetic coil, and its input terminal connected to the power supply.

3. The chest compression monitoring device as described in claim 2, characterized in that, The electromagnetic coil has a flat conductor cross-section, and / or the electromagnetic coil has a Z-shaped folded winding structure.

4. The chest compression monitoring device as described in claim 1, characterized in that, The data processing module includes a dynamic compensation unit; The first magnetic field parameter includes the total field strength. and preset reference distance ; The dynamic compensation unit is used to adjust the total field strength of the first magnetic field parameter according to the dynamic compensation unit. and the preset reference distance The total field strength of the second magnetic field parameter Dynamic compensation is performed, and the formula for dynamic compensation is: ； This represents the real-time distance between the magnetic sensing module and the magnetic source module.

5. A method based on the chest compression monitoring device according to any one of claims 1 to 4, characterized in that, include: Acquire the first magnetic field parameters generated by the magnetic source module and the second magnetic field parameters generated by the magnetic sensing module; Based on the first magnetic field parameters, the second magnetic field parameters are dynamically compensated and the real-time distance is calculated; By using the spatial components of multiple magnetic sensing modules, the real-time distance and angle between the magnetic sensing module and the magnetic source module are calculated to determine the pressing depth along the target deformation direction.

6. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program that can run on the processor, and when the processor executes the program, it implements the method as described in claim 5.

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