Vascular function evaluation system and method based on three-dimensional mechanical perception

Abstract

The invention relates to a vascular function evaluation system and method based on three-dimensional mechanical perception. The system comprises a capacitive sensing array used for detecting a generated capacitance field; the miniature probe is used for receiving a control signal of the driving and control module so as to generate three-dimensional motion and detecting capacitance field change generated by blood vessel fluctuation through the capacitive sensing array; the driving and control module is used for driving the miniature probe to perform three-dimensional motion; the signal processing and calculating module is used for calculating the real-time three-dimensional position of the miniature probe relative to the blood vessel according to the capacitance field data and feeding back and controlling the miniature probe to move to correct the real-time three-dimensional position of the miniature probe relative to the blood vessel; and the miniature probe moves and is kept at a target measurement position, receives and processes a target signal acquired by the capacitive sensing array in the measurement process, and completes vascular function evaluation based on the target signal. Vascular function evaluation can be promoted to be converted from indirect speculation to direct measurement, and the precision and practicability of vascular function evaluation are improved.

Description

Technical Field

[0001] This invention relates to the field of bioengineering technology, and in particular to a vascular function assessment system and method based on three-dimensional mechanical sensing. Background Technology

[0002] Cardiovascular disease is the leading cause of sudden death worldwide. Its core pathological basis includes atherosclerosis, arteriosclerosis, and diabetic vascular complications, all of which begin in the early stages of vascular dysfunction. Before identifiable structural changes such as plaques and stenosis are detected, functional disorders such as endothelial dysfunction, decreased vascular wall elasticity, and abnormal blood rheology have already occurred. Therefore, early, non-invasive, and accurate assessment of vascular function is a crucial prerequisite for halting the progression of cardiovascular disease and implementing effective prevention and intervention. Current clinical vascular assessment methods are mainly divided into structural and functional assessments. Structural assessment methods, including ultrasound imaging, CT angiography, and magnetic resonance angiography, can clearly present the anatomical structure of blood vessels, providing direct evidence for diagnosing mid-to-late-stage structural vascular lesions, but lack sensitivity to early functional changes. Functional assessment methods, including flow-mediated vasodilation measurement, brachial pulse wave velocity testing, and pulse wave analysis, focus on acquiring vascular function parameters, but generally suffer from complex procedures, high requirements, and poor repeatability of test results.

[0003] In addition, there are systems that acquire and analyze pulse waves using high-resolution pressure sensors based on single points or one-dimensional arrays. These systems employ one or more highly sensitive piezoelectric, piezoresistive, or capacitive pressure sensors, placed on superficial arteries such as the radial artery in the form of a linear array or a single probe. The sensors measure the temporal changes in the normal (Z-axis) pressure on the skin surface caused by arterial pulsation, i.e., the one-dimensional pulse wave waveform. By analyzing the one-dimensional waveform, macroscopic physiological parameters such as arterial stiffness and cardiac output can be indirectly estimated.

[0004] However, when traditional high-resolution pressure sensors are used for pulse wave acquisition and analysis in vascular function assessment, the sensors can only measure normal pressure, resulting in a significant lack of sensing dimension. Furthermore, micro-vibrations from different parts of the blood vessel and the influence of adjacent tissues are mixed in a single signal, creating information coupling and making it difficult to distinguish the signal source. Existing pressure sensors are optimized for macroscopic pulse wave measurement, resulting in limitations in accuracy and dynamic range, and vascular function assessment suffers from indirectness and lag. Therefore, traditional vascular function assessment methods often suffer from low accuracy and limited practicality due to missing sensing dimensions, insufficient spatial resolution and information coupling, limited accuracy and dynamic range, and indirectness and lag. Summary of the Invention

[0005] Therefore, in order to solve the above-mentioned technical problems, a vascular function assessment system and method based on three-dimensional mechanical perception is provided, which can promote the transformation of vascular function assessment from indirect inference to direct measurement, and improve the accuracy and practicality of vascular function assessment.

[0006] A vascular function assessment system based on three-dimensional biomechanical sensing, the system comprising an interconnected capacitive sensor array, a three-dimensionally movable miniature probe, a drive and control module, and a signal processing and computation module, wherein:

[0007] The capacitive sensing array is arranged in a two-dimensional matrix on a flexible substrate to detect the distribution and changes of the capacitive field caused by fluctuations in blood vessels on the body surface.

[0008] The micro probe is positioned above the capacitive sensing array and connected to the drive and control module. It is used to receive control signals from the drive and control module and generate three-dimensional motion in directions parallel and perpendicular to the plane of the capacitive sensing array according to the control signals.

[0009] The signal processing and calculation module is electrically connected to both the capacitive sensing array and the driving and control module, and is used for:

[0010] Based on the capacitance field distribution and changes detected by the capacitive sensing array, the real-time three-dimensional position of the micro probe relative to the target blood vessel is calculated.

[0011] The control signal is generated based on the real-time three-dimensional position, and the micro probe is driven to move through the drive and control module to correct the position and contact state of the micro probe relative to the target blood vessel.

[0012] After the miniature probe arrives at and remains at the target measurement position according to the control signal, it receives and processes the target signal collected by the capacitive sensing array during the measurement process to complete the vascular function assessment.

[0013] In one embodiment, the capacitive sensing array is a flexible capacitive sensing array, comprising MEMS capacitive sensing units arranged in a matrix on a flexible substrate, each of the MEMS capacitive sensing units comprising:

[0014] Flexible dielectric material layer;

[0015] A rolled metal foil layer is disposed on the upper surface of the flexible dielectric material layer as a bottom electrode, and the bottom electrode provides mechanical support;

[0016] A flexible metal thin film layer is disposed on the lower surface of the flexible dielectric material layer as a movable electrode. The movable electrode is patterned through microfabrication technology to form the force-sensitive structure of the MEMS capacitive sensing unit.

[0017] The flexible dielectric material layer, the rolled metal foil layer, and the flexible metal thin film layer together constitute the sensitive structure of the MEMS capacitive sensing unit and are integrated on the flexible substrate.

[0018] In one embodiment, the drive and control module uses one or more combinations of electromagnetic drive, piezoelectric drive, or electrostatic drive to drive the micro probe to perform three-dimensional motion.

[0019] In one embodiment, the signal processing and calculation module is configured to execute an automatic blood vessel tracing and position maintenance program, the automatic blood vessel tracing and position maintenance program including:

[0020] Based on the change in capacitance field of the capacitive sensing array, the course and the point of strongest pulsation of the target blood vessel are identified;

[0021] The microprobe is controlled to move above the target measurement position, and the position of the microprobe is dynamically adjusted based on continuous capacitive field feedback to track the movement of the blood vessel and maintain a preset contact force.

[0022] In one embodiment, the target measurement action of the microprobe includes one or more of the following:

[0023] Periodic micro-oscillations are performed in a direction perpendicular to the body surface to apply the main dynamic excitation;

[0024] Maintain static contact to enable the capacitive sensing array to perform passive signal acquisition;

[0025] The sensor performs scanning motion within the plane of the capacitive sensing array to cooperate with the capacitive sensing array in acquiring spatial distribution information.

[0026] In one embodiment, the system further includes a readout integrated circuit electrically connected to the capacitive sensing array, used to cyclically scan each sensing unit in the array in a time-division multiplexed manner, read the capacitance change signals of each sensing unit in three axes, and convert them into voltage signals for processing by the signal processing and calculation module.

[0027] A vascular function assessment method based on three-dimensional biomechanical sensing, applied to a vascular function assessment system based on three-dimensional biomechanical sensing, the method comprising:

[0028] The distribution and changes of the capacitive field caused by blood vessel fluctuations are detected by a capacitive sensing array.

[0029] Based on the capacitance field distribution and changes, the real-time position of the three-dimensionally movable miniature probe relative to the target blood vessel is calculated.

[0030] The microprobe is driven to move according to the generated control signal, and the position and contact force of the microprobe relative to the target blood vessel are corrected to reach and stabilize at the optimal measurement site.

[0031] After the miniature probe stabilizes, the target capacitance field signal is acquired through the capacitive sensing array.

[0032] The target capacitance field signal is processed to extract characteristic parameters related to vascular wall elasticity, hemodynamics, or endothelial function, and vascular function is assessed based on these characteristic parameters.

[0033] In one embodiment, the target capacitance field signal is processed, including:

[0034] The output signal of the capacitive sensing array is represented as a data stream containing time, spatial coordinates, and three-dimensional axial components;

[0035] Different mechanical components corresponding to radial pulsation of blood vessels, shear motion of the vessel wall, and blood flow eddies are separated from the data stream;

[0036] Based on the separated mechanical components, vascular function assessment parameters were calculated.

[0037] In one embodiment, after the microprobe stabilizes, the microprobe is controlled to vibrate at a frequency adjustable amplitude in a direction perpendicular to the body surface, while the frequency response of the active excitation is measured by the capacitive sensing array to obtain the dynamic viscoelastic properties of the tissue in the blood vessel.

[0038] The aforementioned vascular function assessment system and method based on three-dimensional mechanical sensing detects capacitance field data through a capacitance sensing array, enabling non-contact mapping of the body surface's mechanical field. By utilizing capacitance changes detected by the sensing array itself, the position and trajectory of the execution probe in three-dimensional space are located in real time and with precision, forming a closed-loop control system. The miniature probe can track the minute movements of blood vessels in real time, ensuring continuous signal stability during the measurement process. This can promote the transformation of vascular function assessment from indirect inference to direct measurement, improving the accuracy and practicality of vascular function assessment. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of a vascular function assessment system based on three-dimensional mechanical sensing in one embodiment;

[0040] Figure 2 This is a schematic diagram of a two-dimensional matrix form of a capacitive sensing array in one embodiment;

[0041] Figure 3 This is a schematic diagram of the cross-sectional structure of a MEMS capacitive sensing unit in one embodiment of a capacitive sensing array.

[0042] Figure 4 This is a flowchart illustrating a vascular function assessment method based on three-dimensional mechanical sensing in one embodiment. Detailed Implementation

[0043] 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 specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0044] In one embodiment, such as Figure 1 As shown, a vascular function assessment system based on three-dimensional biomechanical sensing is provided, including an interconnected capacitive sensor array 110, a three-dimensionally movable miniature probe 120, a drive and control module 130, and a signal processing and calculation module 140, wherein:

[0045] The capacitive sensing array 110 is arranged in a two-dimensional matrix on a flexible substrate to detect the distribution and changes of the capacitive field caused by fluctuations in blood vessels on the body surface.

[0046] The miniature probe 120 is positioned above the capacitive sensor array 110 and connected to the drive and control module 130. It is used to receive control signals from the drive and control module 130 and generate three-dimensional motion in directions parallel and perpendicular to the plane of the capacitive sensor array 110 according to the control signals.

[0047] The signal processing and calculation module 140 is electrically connected to the capacitive sensor array 110 and the drive and control module 130, respectively, and is used for:

[0048] Based on the distribution and changes in capacitance field detected by the capacitive sensing array 110, the real-time three-dimensional position of the miniature probe 120 relative to the target blood vessel is calculated.

[0049] Based on the real-time three-dimensional position, a control signal is generated, and the micro probe 120 is driven to move through the drive and control module 130 to correct the position and contact state of the micro probe 120 relative to the target blood vessel.

[0050] After the miniature probe 120 arrives at and remains at the target measurement position according to the control signal, it receives and processes the target signal collected by the capacitive sensing array 110 during the measurement process to complete the vascular function assessment.

[0051] In this embodiment, as Figure 2As shown, in the capacitive sensing array, each arrayed top electrode unit 201 is arranged in a two-dimensional matrix on a flexible substrate. The flexible substrate 202 is made of polyimide or elastomer material, combining wearing comfort and skin adhesion, and can be encapsulated as a wearable patch or wristband to suit surface blood vessel detection scenarios. A top electrode encapsulation layer is also provided on the capacitive sensing array. Alternatively, a piezoresistive material can be fabricated on a microstructure (such as a crossbeam or diaphragm) capable of sensing triaxial strain, sensing stress through resistance changes, and then deducing acceleration; this can also form an array. The core function of the capacitive sensing array is to detect the distribution and changes in the capacitive field caused by fluctuations in surface blood vessels. That is, when vascular pulsation, blood flow, or vascular wall vibration causes three-dimensional micro-displacement on the body surface, the MEMS capacitive sensing unit undergoes micrometer-level displacement, triggering changes in the spacing or effective overlap area of ​​the sensing capacitor, thereby producing a precise change in capacitance. Through differential capacitors or decoupling circuits in the capacitive sensing array, the capacitance change signal can be converted into mechanical signals corresponding to the X, Y, and Z axes, providing raw data for vascular localization and functional parameter extraction. In one embodiment, an array composed of integrated waveguides, gratings, or micro-interferometer units can be used to non-contactly measure the three-dimensional micro-displacement of the skin surface by detecting changes in the phase and intensity of reflected or transmitted light.

[0052] In one embodiment, such as Figure 3 As shown, the capacitive sensing array is a flexible capacitive sensing array, including MEMS capacitive sensing units arranged in a matrix on a flexible substrate. Each MEMS capacitive sensing unit includes: a flexible dielectric material layer 301; a rolled metal foil layer 302 disposed on the upper surface of the flexible dielectric material layer as a bottom electrode, which provides mechanical support; and a flexible metal thin film layer 303 disposed on the lower surface of the flexible dielectric material layer as a movable electrode. The movable electrode is patterned using microfabrication technology to form the force-sensitive structure of the MEMS capacitive sensing unit. The flexible dielectric material layer, the rolled metal foil layer, and the flexible metal thin film layer together constitute the sensitive structure of the MEMS capacitive sensing unit and are integrated on the flexible substrate 304.

[0053] The capacitive sensing array consists of multiple MEMS capacitive sensing units arranged in a regular matrix. The unit side length ranges from 100µm to 250µm, and the center-to-center spacing ranges from 100µm to 250µm to meet the size requirements of blood vessels at different locations. Its spatial resolution is far higher than the artery diameter, enabling complete coverage of the target blood vessel and surrounding tissue area, depicting the mechanical contour of the artery. The electrodes of each MEMS capacitive sensing unit are led out via micron-scale metal wires (such as copper or gold) and connected to a multiplexing and readout integrated circuit (ASIC) located at the edge of the array. Different types of sensing units can also be integrated on the same flexible substrate; for example, some units can be high-sensitivity Z-axis sensors, while others can be XY-axis shear force sensors, optimizing performance and power consumption. Alternatively, a smaller number of higher-precision sensing units can be used, with software-controlled dynamic selection of activation areas or mechanical movement of a small, dense array for scanning, to synthesize high-resolution mechanical field images, reducing system complexity and cost.

[0054] Specifically, in this embodiment, each MEMS capacitive sensing unit includes a bottom electrode plate, a movable probe-cantilever beam system, and a top cover plate. The movable probe is connected to the anchor point through four L-shaped or folded beam cantilever arms and is suspended above the bottom electrode plate, allowing it to move freely in the X, Y, and Z directions. The bottom electrode plate and the movable probe together form a detection capacitor. The top cover plate has a cavity for sealing and forming a protective environment to avoid external interference.

[0055] The miniature probe is positioned above the capacitive sensing array and connected to the drive and control module. The size of the miniature probe is designed to allow it to be precisely positioned in the electric field of the capacitive sensing array, and its motion trajectory can be tracked in real time by the capacitance changes detected by the array.

[0056] In one embodiment, the target measurement action of the microprobe includes one or more of the following: periodic micro-oscillation in a direction perpendicular to the body surface to apply main dynamic excitation; maintaining static contact to enable passive signal acquisition by the capacitive sensing array; and performing scanning motion in the plane of the capacitive sensing array to cooperate with the capacitive sensing array to acquire spatial distribution information.

[0057] The core function of the miniature probe is to receive control signals from the drive and control module, and generate three-dimensional motion in the plane parallel to the capacitive sensing array (XY direction) and perpendicular to the array plane (Z direction) according to the control signals, so as to realize the tracking of the target blood vessel, the approximation and stable contact of the measurement site, and provide mechanical support for accurate measurement.

[0058] In one embodiment, the drive and control module employs one or more combinations of electromagnetic drive, piezoelectric drive, or electrostatic drive to drive the micro probe in three-dimensional motion. The core function of the drive and control module is to receive control signals output from the signal processing and calculation module, convert electrical signals into mechanical driving force, and precisely control the three-dimensional motion trajectory, speed, and contact force of the micro probe.

[0059] In this embodiment, through the precise driving of the drive and control module, the miniature probe can automatically track along the blood vessel direction, smoothly approach the skin surface, and stably stay at the target measurement position, ensuring that the contact state between the probe and the body surface during the measurement process meets the preset requirements, and avoiding signal distortion caused by improper contact pressure or positional deviation.

[0060] In one embodiment, the signal processing and computing module is configured to execute an automatic blood vessel tracking and position maintenance program, which includes: identifying the direction and strongest pulsation point of the target blood vessel based on the capacitance field change of the capacitive sensing array; controlling the micro probe to move above the target measurement position, and dynamically adjusting the position of the micro probe to track the movement of the blood vessel based on continuous capacitance field feedback, and maintaining a preset contact force.

[0061] The signal processing and computation module is electrically connected to both the capacitive sensing array and the drive and control module. It is the core control and data processing unit of the system, integrating functions such as signal amplification, filtering, analog-to-digital conversion, data processing, and control logic generation. Specifically, the signal processing and computation module can include functions such as signal acquisition, data output, feature extraction, and visualization.

[0062] After amplification, filtering, and analog-to-digital conversion, the system outputs a four-dimensional data stream: Data = f(x, y, t, axis), where (x, y) are the spatial coordinates of the sensing unit, t is time, and axis represents the three axes X, Y, and Z, forming a complete three-dimensional spatiotemporal digital image of the body surface micro-vibration. The high-dimensional raw data acquired by the signal processing and calculation module can be directly used for radial-ulnar artery pulse sign measurement, ultimately generating a dynamic three-dimensional motion vector diagram of the skin surface during vascular pulsation.

[0063] During feature extraction, the signal processing and computation module analyzes the amplitude, phase, spectrum, and coherence of signals at different spatial points and along different axes to separate components from different physical vector sources, such as radial pulsation, shear fluctuations, and high-frequency turbulence. For example, the Z-axis signal array diagram can reflect the spatial propagation of the main pulsation wave; the spatial distribution of specific high-frequency components along the X / Y axes is related to blood flow shear force. The data acquired and processed by the signal processing and computation module is ideal input for developing subsequent algorithms for quantitatively inverting the elastic distribution of the vessel wall, endothelial function index, and estimating blood flow viscosity.

[0064] In this embodiment, the signal processing and calculation module receives the capacitance field distribution and change signals output by the capacitive sensing array, analyzes the spatial distribution characteristics of the capacitance change through a preset positioning algorithm, and identifies the surface projection position of the target blood vessel. At the same time, based on the capacitance field change around the micro probe detected by the capacitive sensing array, the real-time three-dimensional coordinates of the micro probe are calculated, and a positional relationship model between the micro probe and the target blood vessel is established.

[0065] Next, the signal processing and calculation module generates targeted control signals based on real-time 3D position information. These signals, transmitted through the drive and control module, move the miniature probe in the XY directions to automatically track the target blood vessel. In the Z direction, the distance between the probe and the skin is adjusted, ensuring the probe tip approaches and stably contacts the skin surface with a preset contact force. This corrects the probe's positional and contact deviations relative to the target blood vessel, ensuring the probe is in the optimal measurement position. Throughout this process, the signal processing and calculation module continuously adjusts the control commands by receiving real-time capacitance change signals from the array, forming a closed-loop control system to guarantee the accuracy and stability of the position correction.

[0066] After the miniature probe arrives at and remains at the target measurement position, the signal processing and calculation module receives the target signal collected by the capacitive sensing array during the measurement process, performs preprocessing such as amplification, filtering, and analog-to-digital conversion on the signal to remove environmental noise and interference signals; then, through feature extraction algorithms, it extracts feature parameters related to vascular wall elasticity, hemodynamics, and endothelial function from the preprocessed signal; finally, it analyzes the feature parameters and outputs the vascular function assessment results, completing the entire process from signal acquisition to functional assessment.

[0067] In one embodiment, a vascular function assessment system based on three-dimensional mechanical sensing further includes a readout integrated circuit (ASIC) electrically connected to a capacitive sensing array for cyclically scanning each sensing unit in the array in a time-division multiplexed manner, reading the capacitance change signals of each sensing unit in three axes, and converting them into voltage signals for processing by the signal processing and calculation module.

[0068] The readout integrated circuit is electrically connected to the capacitive sensing array and is integrated into the edge region of the capacitive sensing array. It is the core unit for efficient acquisition of three-dimensional capacitance change signals. Its core function is to cyclically scan each sensing unit in the array in a time-division multiplexing manner, read the capacitance change signals of each sensing unit in the X, Y, and Z axes, and convert them into voltage signals for processing by the signal processing and calculation module.

[0069] Specifically, the readout integrated circuit incorporates a multiplexer that uses time-division multiplexing technology to select each sensing unit in the array sequentially or in parallel according to a preset timing sequence, achieving full coverage scanning of the entire sensing array. The scanning frequency is adapted to the dynamic response range of the sensing units, ensuring that no microscopic vibration signals are missed. For each selected sensing unit, the readout integrated circuit synchronously or rapidly reads the capacitance changes along its corresponding X, Y, and Z axes. Through a built-in capacitance-to-voltage conversion circuit, the weak capacitance change signal is converted into a voltage signal that is easy to amplify and transmit. During the conversion process, low-noise design suppresses environmental interference, ensuring signal integrity. The readout integrated circuit integrates preliminary signal buffering and noise reduction circuitry to perform preliminary filtering on the converted voltage signal, removing high-frequency noise and power supply interference, providing a high-quality raw signal for accurate analysis by subsequent signal processing and calculation modules.

[0070] In one embodiment, the vascular function assessment system based on three-dimensional biomechanical sensing may further include a data interface and a power supply for outputting digitized high-dimensional data streams to a host computer or mobile device for subsequent analysis and for providing system power management. In this embodiment, each sensing unit integrates an LC resonant circuit whose resonant frequency varies with capacitance (i.e., mechanical input); by wirelessly scanning the resonant frequency spectrum of the entire array with an external RF reader, the mechanical state at each point can be retrieved, achieving a completely wireless wearable experience. A simple CMOS switching circuit can also be integrated next to each sensing unit to directly convert analog capacitance changes into pulse width modulation (PWM) or frequency modulation signals for digital output, enhancing anti-interference capabilities.

[0071] This application provides a vascular function assessment system based on three-dimensional mechanical sensing. By employing a time-division multiplexing method with a readout integrated circuit to cyclically scan the sensor array, it achieves high-speed, parallel acquisition of triaxial capacitance change signals from each sensor unit. This avoids signal delay and distortion caused by traditional serial reading, ensuring the synchronization and integrity of the three-dimensional mechanical signals. Simultaneously, the integration of capacitance-to-voltage conversion and preliminary noise reduction shortens the signal transmission path, reduces the impact of external interference on weak capacitance signals, and guarantees signal quality. The capacitive sensor array, combined with the precise reading of the readout integrated circuit, can simultaneously capture mechanical signals along the X, Y, and Z axes, comprehensively acquiring key information such as vascular shear stress, blood flow eddies, and lateral vascular wall vibration. This avoids the loss of mechanical information caused by traditional single-axis normal pressure measurement, providing a complete data foundation for multi-dimensional assessment of vascular function. The micron-level sensor unit size and spacing design, combined with the high-sensitivity signal conversion capability of the readout integrated circuit, enables… The system can capture micro-Newton level mechanical signals and microscopic vibrations at frequencies of hundreds of hertz, accurately identifying early subclinical functional changes in blood vessels and solving the problem of insufficient sensitivity of traditional technologies to early lesions. Through the closed-loop linkage of signal processing and computing modules, drive and control modules, and readout integrated circuits, it achieves automatic positioning of target blood vessels, automatic probe tracking, and automatic correction of measurement sites, eliminating reliance on operator experience, lowering the operational threshold, and ensuring the consistency and repeatability of each measurement, thus improving the reliability of clinical applications. The output three-dimensional spatiotemporal mechanical field data is a four-dimensional data stream, which can directly map multi-dimensional functional information such as vascular wall compliance and blood flow characteristics, facilitating the development of quantitative inversion algorithms to achieve accurate differentiation of vascular functional abnormalities in different dimensions and improve the specificity and directness of assessment results. The flexible substrate and wearable packaging design, combined with the miniaturized integration characteristics of the readout integrated circuit, enable the system to balance wearable comfort, signal stability, and device portability.

[0072] In one embodiment, such as Figure 4 As shown, a method for assessing vascular function based on three-dimensional biomechanical sensing is provided, including the following steps:

[0073] Step 402: Detect the distribution and changes of the capacitance field caused by blood vessel fluctuations using a capacitive sensing array;

[0074] Step 404: Calculate the real-time position of the three-dimensionally movable miniature probe relative to the target blood vessel based on the distribution and changes of the capacitance field.

[0075] Step 406: Drive the micro probe to move according to the generated control signal, correct the position and contact force of the micro probe relative to the target blood vessel, and reach and stabilize at the optimal measurement site;

[0076] Step 408: After the miniature probe stabilizes, the target capacitance field signal is acquired through a capacitive sensing array.

[0077] Step 410: Process the target capacitance field signal, extract feature parameters related to vascular wall elasticity, hemodynamics, or endothelial function, and complete vascular function assessment based on the feature parameters.

[0078] In one embodiment, a vascular function assessment method based on three-dimensional mechanical sensing may further include a process of processing the target capacitive field signal. The specific process includes: representing the output signal of the capacitive sensing array as a data stream containing time, spatial coordinates, and three-dimensional axial components; separating different mechanical components corresponding to radial pulsation, shear motion of the vessel wall, and blood flow eddies from the data stream; and calculating vascular function assessment parameters based on the separated mechanical components.

[0079] In one embodiment, after the microprobe stabilizes, the microprobe is controlled to vibrate at a frequency adjustable amplitude in a direction perpendicular to the body surface, while the frequency response of the active excitation is measured by a capacitive sensing array to obtain the dynamic viscoelastic properties of the tissue in the blood vessel.

[0080] Those skilled in the art will understand that all or part of the processes in the systems and methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0082] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A three-dimensional mechanical perception-based vascular function assessment system, characterized in that, The system comprises a capacitive sensing array, a three-dimensionally movable micro-probe, a driving and control module, a signal processing and calculation module, wherein: The capacitive sensing array is arranged in a two-dimensional matrix form on a flexible substrate, and is used for detecting the distribution and change of the capacitive field caused by the fluctuation of the body surface blood vessels; The micro-probe is arranged above the capacitive sensing array, and is connected with the driving and control module, and is used for receiving the control signal sent by the driving and control module, and generating three-dimensional motion in the directions parallel and perpendicular to the plane of the capacitive sensing array according to the control signal; The signal processing and calculation module is electrically connected with the capacitive sensing array and the driving and control module respectively, and is used for: calculating the real-time three-dimensional position of the micro-probe relative to the target blood vessel according to the distribution and change of the capacitive field detected by the capacitive sensing array; generating the control signal based on the real-time three-dimensional position, and driving the micro-probe to move through the driving and control module, so as to correct the position and contact state of the micro-probe relative to the target blood vessel; after the micro-probe reaches and remains at the target measurement position according to the control signal, receiving and processing the target signal collected by the capacitive sensing array during the measurement process, and completing the blood vessel function evaluation.

2. The three-dimensional mechanics sensing based vascular function assessment system according to claim 1, wherein, The capacitive sensing array is a flexible capacitive sensing array, comprising a plurality of MEMS capacitive sensing units arranged in a matrix form on a flexible substrate, each of the MEMS capacitive sensing units comprising: a flexible dielectric material layer; a rolled metal foil layer arranged on the upper surface of the flexible dielectric material layer as a bottom electrode, the bottom electrode providing mechanical support; a flexible metal film layer arranged on the lower surface of the flexible dielectric material layer as a movable electrode, the movable electrode being patterned to form a force sensing structure of the MEMS capacitive sensing unit through a micro-processing process; wherein the flexible dielectric material layer, the rolled metal foil layer and the flexible metal film layer jointly constitute a sensitive structure of the MEMS capacitive sensing unit and are integrated on the flexible substrate.

3. The three-dimensional mechanics sensing based vascular function assessment system according to claim 1, wherein, The driving and control module adopts one or a combination of electromagnetic driving, piezoelectric driving or electrostatic driving to drive the micro-probe to move in three dimensions.

4. The three-dimensional mechanics sensing based vascular function assessment system according to claim 1, wherein, The signal processing and calculation module is configured with a blood vessel automatic tracking and position maintenance program, which comprises: identifying the direction and the point of strongest pulsation of the target blood vessel based on the change of the capacitive field of the capacitive sensing array; controlling the micro-probe to move above the target measurement position, and dynamically adjusting the position of the micro-probe to track the movement of the blood vessel and maintain the preset contact force based on the continuous capacitive field feedback.

5. The three-dimensional mechanics sensing based vascular function assessment system according to claim 1, wherein, The target measurement action of the micro-probe comprises one or more of the following: periodic micro-oscillation in the direction perpendicular to the body surface to apply active dynamic excitation; maintaining static contact to enable passive signal acquisition of the capacitive sensing array; scanning motion in the plane of the capacitive sensing array to cooperate with the capacitive sensing array to obtain spatial distribution information.

6. The three-dimensional mechanics sensing based vascular function assessment system according to claim 1, wherein, The system further comprises a readout integrated circuit electrically connected to the capacitive sensing array, for cyclically scanning each sensing unit in the array in a time-division multiplexing manner, reading the capacitive change signals of each sensing unit in three axial directions, and converting the signals into voltage signals for processing by the signal processing and calculation module.

7. A method for evaluating vascular function based on three-dimensional mechanical perception, applied to the system for evaluating vascular function based on three-dimensional mechanical perception according to any one of claims 1-6, characterized in that, The method comprises: detecting the capacitive field distribution and change caused by blood vessel fluctuation through a capacitive sensing array; calculating the real-time position of a three-dimensionally movable micro-probe relative to a target blood vessel based on the capacitive field distribution and change; driving the micro-probe to move according to the generated control signal, correcting the position and contact force of the micro-probe relative to the target blood vessel, and reaching and stabilizing at an optimal measurement site; after the micro-probe is stabilized, collecting a target capacitive field signal through the capacitive sensing array; processing the target capacitive field signal, extracting feature parameters related to blood vessel wall elasticity, hemodynamics or endothelial function, and completing blood vessel function evaluation based on the feature parameters.

8. The method for assessing vascular function based on three-dimensional mechanoperception according to claim 7, characterized in that, Processing the target capacitive field signal comprises: representing the output signal of the capacitive sensing array as a data stream containing time, spatial coordinates and three-dimensional axial components; separating different mechanical components corresponding to blood vessel radial pulsation, tube wall shear motion and blood flow vortex from the data stream; calculating blood vessel function evaluation parameters based on the separated mechanical components.

9. The method for vascular function assessment based on three-dimensional mechanoperception according to claim 7, characterized in that, After the micro-probe is stabilized, controlling the micro-probe to perform frequency-adjustable micro-amplitude vibration in a direction perpendicular to the body surface, and simultaneously measuring the frequency response of the active excitation through the capacitive sensing array to obtain the dynamic viscoelastic properties of the tissue in the blood vessel.

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