CN-122004829-A - Bidirectional sensing airflow sensing device and method capable of adjusting and controlling sensitivity

CN122004829ACN 122004829 ACN122004829 ACN 122004829ACN-122004829-A

Abstract

The invention discloses a bidirectional sensing airflow sensing device and a bidirectional sensing airflow sensing method capable of regulating and controlling sensitivity, which relate to the technical field of wearable respiration monitoring and airflow sensing, and comprise an oral-nasal mask, wherein an airflow duct is arranged on the oral-nasal mask, a baffle type sensing component is arranged in the airflow duct, the baffle type sensing component is connected with an adjusting component, and the adjusting component is arranged outside the airflow duct; the sensing sensitivity of the baffle type sensing assembly is regulated and controlled by regulating the size of the baffle type sensing assembly through the regulating assembly. The bidirectional sensing airflow sensing device and the bidirectional sensing airflow sensing method with adjustable sensitivity have the advantages of high precision, bidirectional integrated monitoring, adjustable sensitivity and compact structure, and are suitable for various scenes such as clinical diagnosis, postoperative rehabilitation, home monitoring and motion evaluation.

Inventors

YANG BAO
CHEN JIANHUI
ZHOU LICHENG
LIU YIPING
LIU ZEJIA
JIANG ZHENYU
TANG LIQUN

Assignees

华南理工大学

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (10)

1. The bidirectional sensing airflow sensing device capable of adjusting and controlling sensitivity is characterized by comprising an oral-nasal mask, wherein an airflow duct is arranged on the oral-nasal mask, a baffle type sensing component is arranged in the airflow duct, the baffle type sensing component is connected with an adjusting component, and the adjusting component is arranged outside the airflow duct; and the sensing sensitivity of the baffle type sensing assembly is regulated and controlled by changing the size of the baffle type sensing assembly through the regulating assembly.
2. The device of claim 1, wherein the flow conduit is a single continuous flow path for both inspiration and expiration gases to flow through the detection section of the baffle sensing assembly.
3. The bidirectional sensing airflow sensing device with adjustable sensitivity according to claim 2, wherein the baffle sensing assembly comprises a baffle body arranged inside the airflow duct, a signal processing circuit and a sensing unit are integrated on the baffle body, and the sensing unit is connected with a signal acquisition and processing module and performs data transmission; The baffle body comprises a central shaft, a plurality of fan blades are circumferentially distributed on the outer side of the central shaft, each fan blade is connected with the central shaft through a connecting piece, the relative position between the fan blades and the central shaft is changed under the driving action of the adjusting component, the relative position is changed from the midpoint of the edge of each fan blade to the edge endpoint of each fan blade, the baffle body is unfolded or folded, radial amplification and shrinkage of the baffle body are achieved, the size of the baffle body is changed to enable the flow area in the air flow duct to be changed, and then the pressure difference response amplitude in the air flow duct is adjusted to adjust the sensing sensitivity of the baffle type sensing component.
4. The device of claim 3, wherein the sensing unit is a piezoresistive/pressure-capacitive pressure sensing unit for collecting pressure changes in the air flow conduit and outputting an electrical signal; the sensing unit is of a waterproof packaging structure.
5. The device of claim 4, wherein the adjusting assembly comprises a knob disposed outside the air flow conduit, the lower portion of the knob is connected with one end of a transmission member, and the other end of the transmission member is connected with the baffle body; rotating the knob increases or decreases the size of the baffle body, changes the gap size of the annular channel between the baffle body and the inner wall of the air flow conduit, and further changes the flow area.
6. A method of applying a sensitivity-controllable, bi-directional sensing air flow sensing device according to any of the preceding claims 1-5, comprising the steps of: s1, wearing an oral-nasal mask to enable inspiration and expiration gases to flow through a detection section in an airflow duct; s2, changing the size of the baffle body through the adjusting component so as to change the flow area A, and setting the sensing sensitivity and the air resistance level, wherein the following formula is shown: ; In the formula, Indicating the flow area in the air flow conduit as When the baffle plate senses the air flow resistance at the component, Indicating the flow area within the air flow conduit, And Representing the flow area The scaling factor of the effect of the variation on the resistance to the air flow, And Representing the flow area The index parameter of the influence on the air flow resistance is changed, The instantaneous airflow flow of the airflow conduit is represented, and the positive and negative correspond to the exhalation and inhalation directions respectively; S3, collecting pressure change signals in the airflow guide tube, outputting electric signals, and performing signal processing and data collection on the electric signals; s4, performing zero compensation and direction discrimination on the acquired electric signals, and reconstructing the inspiration/expiration bidirectional air flow; and S5, calculating and outputting respiratory parameters based on the reconstructed air flow.
7. The method of a sensitivity adjustable bi-directional sensing airflow sensing device according to claim 6, wherein S2 comprises: s21, selecting a target size of the baffle plate according to the use scene; s22, rotating the knob to adjust the size of the baffle body to the target size through transmission of the transmission piece; S23, keeping the baffle body in a target size state, and recording corresponding adjusting gears or size parameters for subsequent calibration and calculation.
8. The method of a sensitivity adjustable bi-directional sensing airflow sensing device according to claim 7, wherein S3 comprises: s31, the sensing unit collects pressure changes caused by bidirectional airflow in the detection section and outputs an electric signal; S32, the signal processing circuit amplifies and filters the electric signal, performs analog-to-digital conversion to obtain a pressure related signal, and transmits the pressure related signal to the signal acquisition and processing module for display and storage through an interface; And S33, performing time synchronous sampling and time sequence storage on the pressure related signals, wherein the sampling frequency is set according to the breathing signal bandwidth so as to ensure the integrity of inspiration/expiration waveforms.
9. The method of a sensitivity adjustable bi-directional sensing airflow sensing device according to claim 8, wherein S4 comprises: S41, carrying out baseline estimation and zero compensation on the acquired electric signals to obtain pressure related signals after zero compensation; s42, judging an inspiration phase and an expiration phase based on the signal polarity or the threshold value; s43, converting the pressure related signals into corresponding bidirectional air flow according to a pre-established calibration relation; The calibration relation is a pressure-air flow mapping relation under different adjusting gears or different baffle sizes, and is respectively established in two directions of inspiration and expiration or is established by adopting a unified parameterized model.
10. The method of a sensitivity-controllable, bi-directional, sensored flow sensor apparatus of claim 9 wherein said respiratory parameters of S5 include tidal volume, minute ventilation, and respiratory rate, wherein tidal volume and minute ventilation are obtained by time integration of reconstructed flow and respiratory rate is obtained by identification of respiratory cycle.

Description

Bidirectional sensing airflow sensing device and method capable of adjusting and controlling sensitivity Technical Field The invention relates to the technical field of wearable respiration monitoring and airflow sensing, in particular to a bidirectional sensing airflow sensing device and method with adjustable sensitivity. Background The human breathing process can generate bidirectional airflow changes of inspiration and expiration, and the airflow changes contain rich physiological information such as ventilation volume, breathing rhythm and the like of an individual. Capturing and analyzing such information for breath detection is of great importance. Continuous and accurate perception and quantitative analysis of respiratory airflow are particularly critical in the scenes of clinical diagnosis, early respiratory disease identification and rehabilitation therapy, postoperative function recovery evaluation, home health monitoring, exercise evaluation and the like. There are significant limitations to the currently common wearable respiratory monitoring technology. The integrated gas pressure sensor of the mask provided by the related invention is characterized in that sensing elements are arranged in a local area of a cavity of the mask, the overall ventilation is deduced through local pressure change, in practice, the nasal/oral respiratory contribution changes along with the position and the strength, and the respiratory flow field in the mask is uneven, so that the corresponding relation between local signals and the global ventilation is difficult to stabilize, and accurate reconstruction of parameters such as tidal volume, minute ventilation and the like cannot be supported. In addition, the structural parameters of the existing scheme are fixed, the sensitivity is difficult to regulate and control according to different people and scenes, and larger air resistance is easily introduced when the detection sensitivity is improved, so that wearing comfort and natural breathing state are affected, and the monitoring requirements of the oral-nasal mask for high sensitivity and low air resistance under multiple scenes cannot be met. Meanwhile, part of the scheme is driven by the expiration, so that bidirectional integrated monitoring and stable output of inspiration and expiration under a compact structure are difficult to realize. Although the equipment such as a medical respiration monitor, a respirator, an anesthesia machine and the like can acquire respiratory gas flow and volume change parameters such as respiratory volume, vital capacity, minute ventilation volume and the like, the measurement accuracy is higher, but the equipment usually depends on a special gas circuit and a standardized operation flow, a part of scenes also need an invasive or semi-invasive connection mode, the comfort is poor, and the operation and maintenance requirements are higher, so continuous and effective long-term monitoring is difficult to realize in daily activities such as sleeping, resting and movement and the like, and the miniature integration and multi-scene deployment of a wearable form are not supported. The chest and abdomen belt strain sensor has the advantages of simple structure, comfort in wearing and the like, but indirectly deduces breathing through chest or abdomen wall deformation, is easily influenced by body position change, motion artifacts and individual body type differences, is difficult to realize accurate estimation of quantitative ventilation parameters such as tidal volume, minute ventilation volume and the like, and the temperature/humidity type breathing sensing scheme has the characteristics of easy integration, clear waveform and the like, is suitable for breathing pattern recognition and rhythm assessment, but has signals influenced by environmental baseline drift, material lag and response speed limitation, is difficult to cover the full-flow range of breathing, and cannot accurately reconstruct instantaneous airflow or volume. Therefore, the air flow sensing device and the air flow sensing method which can realize the bidirectional integrated monitoring of inspiration and expiration in a single flow channel under the wearing condition of the oral-nasal mask, can regulate and control the sensing sensitivity so as to realize the compromise of air resistance and wearing comfort in multiple scenes and reconstruct the breathing air flow and ventilation parameters accurately in real time are lacking at present. In particular in wearable respiratory flow quantitative bidirectional monitoring, the prior art has obvious limitations from the aspects of precision, sensitivity and comfort. Disclosure of Invention The invention aims to provide a bidirectional sensing airflow sensing device and method capable of adjusting and controlling sensitivity, and solves the problems in the background technology. In order to achieve the above purpose, the invention provides a bidirectional sensing airflow sens