A compressed oxygen respirator residual time length real-time monitoring system and method

Abstract

This invention discloses a system and method for monitoring the remaining duration of a compressed oxygen respirator. It constructs a dynamic oxygen consumption calculation model by real-time collection of physiological parameters such as firefighters' breathing rate, expiratory volume, inspiratory volume, and exhaled carbon dioxide content, combined with equipment operating parameters such as cylinder replenishment pressure changes, replenishment rate, airbag capacity, and replenishment time. This method calculates real-time oxygen consumption based on the oxygen consumption per breath and breathing rate, and calculates the remaining protection time of the compressed oxygen respirator by comparing the relationship between replenishment rate and real-time oxygen consumption, categorized by mode. Furthermore, this invention provides a monitoring system integrating physiological data collection, environmental monitoring, core processing, and early warning feedback. By integrating multi-source information, dynamically adapting to changes in firefighters' workload, and conforming to the actual workflow of the compressed oxygen respirator, this invention significantly improves the accuracy and real-time performance of remaining duration prediction, providing reliable data support for safe operations and command decisions by firefighters.

Description

Technical Field

[0001] This invention relates to the field of fire rescue equipment monitoring technology, specifically to a real-time monitoring system and method for the remaining time of a compressed oxygen respirator, which is particularly suitable for firefighters to accurately and dynamically monitor the remaining usage time of oxygen respirators in complex rescue environments. Background Technology

[0002] During rescue operations, harsh environments severely threaten the lives of rescue personnel. To avoid inhaling toxic and harmful gases, rescuers must wear respirators. However, due to the uncertainty of the disaster site environment and the intensity of personnel's work, the actual usage time of respirators often differs significantly from the theoretically calculated time, which seriously affects the operational efficiency and safety of fire and rescue personnel.

[0003] Currently, the monitoring of the remaining time of oxygen respirators mostly relies on estimation based on cylinder pressure decay. This involves using the ratio of the current cylinder pressure to the initial pressure, combined with the cylinder volume, to estimate the remaining oxygen supply and usable time. However, existing technologies have the following significant drawbacks: The dynamic changes in work intensity were not taken into account: the existing technology cannot adapt to the situation where the oxygen consumption increases significantly due to the increase in heart rate and respiratory rate caused by high-intensity rescue, resulting in prediction bias.

[0004] The technology is not adapted to the working principle of compressed oxygen respirators: Compressed oxygen respirators have a special working process, including the absorption of carbon dioxide by the reagents and the circulation of oxygen replenishment by the air bags. Existing technology does not connect the oxygen replenishment logic to the air bags, ignores the real-time respiratory demand reflected by the exhalation and inhalation volumes, and does not consider the impact of reagent consumption on the system state.

[0005] The monitoring relies on a single source: Existing technical solutions, such as those disclosed in patent documents with publication numbers CN223183932U and CN110465013B, primarily use cylinder pressure as the sole basis for monitoring and calculation, failing to integrate multi-source information such as the user's physiological state and changes in drug weight, resulting in limited accuracy in calculating remaining time. While patent document with publication number CN120242355B mentions linking firefighters' physiological parameters, it lacks a clear and complete calculation process and formula, making it less feasible.

[0006] In summary, existing technologies urgently need improvement to address issues such as low accuracy in predicting remaining time of compressed oxygen respirators, inability to dynamically adapt to work intensity, and disconnection from the actual working principle of the equipment. Summary of the Invention

[0007] The purpose of this invention is to provide a system and method for monitoring the remaining time of a compressed oxygen respirator, so as to solve the technical problems of low prediction accuracy, poor dynamic adaptability, and insufficient consideration of the working principle of the compressed oxygen respirator in the prior art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for real-time monitoring of the remaining time of a compressed oxygen respirator, comprising the following steps: 1. Real-time acquisition of multi-source data Get the following parameters: Firefighter physiological parameters: respiratory rate f (breaths / minute), expiratory volume (L) 呼 (mL / time), inspiratory volume (L) 吸 (mL / time), and satisfying the inspiratory volume L 吸 > expiratory volume (L) 呼 ; Exhaled gas composition parameters: oxygen content in exhaled gas is α%, and carbon dioxide content is β%; Chemical parameters: Current chemical weight m1 (g) of the compressed oxygen respirator, previous chemical weight m0 (g), and when m1≤m0, a chemical leakage alarm is triggered; Equipment operating parameters: Cylinder pressure P1 (MPa) when the automatic replenishment valve of the compressed oxygen respirator's air bag is currently open, cylinder pressure P0 (MPa) when the automatic replenishment valve of the compressed oxygen respirator's air bag was last opened, replenishment valve opening time T (min), and the rate at which the compressed oxygen cylinder continuously replenishes air to the air bag V. 补气 (mL / min); Airbag status parameters: Gas volume (L) in the airbag when the automatic replenishment valve of the compressed oxygen respirator airbag is open. 实 (mL), the rated oxygen capacity (L) when the airbag is fully inflated. 额 (mL); Time parameter: Sensor signal acquisition time interval Δt (min); Preferably, in the "real-time acquisition of multi-source data", a sliding window filtering method is used to filter the respiratory parameters and remove instantaneous abnormal values ​​caused by coughing and deep breathing; 2. Real-time oxygen consumption calculation Compressed oxygen breathing apparatus regulations require a sufficient supply of agents; therefore, it is assumed that the compressed oxygen cylinder of the apparatus will run out of gas first. The compressed oxygen breathing apparatus will then release L of the firefighter's exhaled gas. 呼 Carbon dioxide in (1- β %)×L 呼 The remaining gas is absorbed and enters the airbag, whereupon the firefighters inhale L of the gas. 吸 At this point, the amount of gas in the airbag decreases due to the firefighter's breathing. 吸 -(1- β %)×L 呼 ,Right now Under the condition that the compressed oxygen breathing apparatus is working properly and the oxygen supply is sufficient, the formula for calculating the amount of oxygen consumed by a firefighter in one breath is: O单次 = L 吸 -(1- β %)×L 呼 ; Real-time oxygen consumption V of firefighters 耗氧 =[L 吸 -(1- β %)×L 呼 ]× f ; 3. Calculation of Remaining Protection Time for Compressed Oxygen Breathing Apparatus The oxygen content when the airbag is fully inflated is L 额 When the amount of gas inside the airbag drops to L 实 At that time, the automatic replenishment valve of the compressed oxygen respirator's air bag opens, replenishing the air volume in the air bag to L. 额 The airbag automatic replenishment valve replenishes air in L each time it opens. 额 -L 实 ; The pressure of the compressed oxygen respirator cylinder before and after filling the air bag with air was monitored by a pressure sensor, and the pressures were P respectively. i (MPa) and P i+1 (MPa) i This represents the number of times the oxygen cylinder of the compressed oxygen respirator replenishes air into the inflator, with a replenishment time of T. Calculate... And round down to get , which is the maximum number of times N can be replenished to the air bag from the current compressed oxygen respirator cylinder; Based on the comparison between gas supply rate and real-time oxygen consumption, the remaining time is calculated in the following two cases: Case (1): When V 补气 ≥V 耗氧 At this time, the airbag is always fully inflated. Excess gas is discharged through the pressure relief valve. When the pressure relief valve of the airbag is opened, the excess gas will be discharged.

[0009] At this point, the oxygen respirator is similar to a non-breathing device, with the remaining protection time t. 剩余 The calculation formula is: t 剩余 = + ,in, f 1 represents the sampling frequency of the pressure sensor; Case (2): When V 补气 <V 耗氧 At that time, the gas in the airbag will slowly descend, and the rate of change of the gas in the airbag is V. 变化 =V 耗氧 -V 补气 ; Opening interval t of the automatic airbag replenishment valve 间隔 = ; Remaining protection time t of compressed oxygen breathing apparatus cylinder 剩余 = .

[0010] On the other hand, the present invention also proposes a monitoring and alarm system for the remaining time of a compressed oxygen respirator, the system comprising: The physiological data acquisition module is used to collect firefighters' heart rate, blood oxygen, respiratory rate, and rescue operation posture in real time. An environmental parameter acquisition module is connected in series at the outlet of the compressed oxygen cylinder to collect cylinder pressure and ambient temperature changes in real time and perform temperature compensation. The drug monitoring module is used to collect the current weight and previous weight of the drug in real time and monitor the drug consumption rate. The core processing module establishes a data connection with each signal acquisition module, has a built-in real-time oxygen consumption fusion model and dynamic iterative correction algorithm, is used to execute the steps of any of the above methods, output the remaining duration prediction value and warning signal, and has data storage function. The feedback and early warning module issues alarm information of corresponding levels based on the analysis results (such as triggering a level 2 warning when the remaining time is less than 20 minutes). The human-computer interaction module is used to display information such as remaining time, cylinder pressure, and physiological parameters, and to receive warning signals and activate corresponding alarm levels. Data transmission module: Used for data interaction with the rear command platform.

[0011] Compared with the prior art, the present invention has the following significant advantages: High prediction accuracy: It integrates multiple parameters such as physiology, equipment, environment, and drugs, breaks through the limitations of single pressure monitoring, and constructs an oxygen supply model that fits the working principle of compressed oxygen respirators, which greatly improves the prediction accuracy of remaining time.

[0012] Highly adaptable to dynamic conditions: It can collect physiological parameters such as respiratory rate and volume in real time and dynamically calculate real-time oxygen consumption. When the workload of firefighters increases sharply, the system can respond quickly and recalculate, ensuring the real-time nature and accuracy of monitoring.

[0013] High equipment compatibility: The algorithm fully considers and integrates the oxygen replenishment logic of the airbag, the change in gas cylinder replenishment pressure, and the replenishment time, making the algorithm highly compatible with the actual oxygen supply process of the equipment.

[0014] Strong anti-interference capability: The system uses a sliding window filtering method to remove instantaneous abnormal values ​​of respiratory parameters and uses temperature compensation to eliminate the error of ambient temperature on pressure monitoring, ensuring the stability and reliability of the system in complex rescue environments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the working process of the compressed oxygen respirator in this invention. Figure 2 This is a schematic diagram of the overall execution flow of the monitoring method of the present invention. Detailed Implementation To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] (I) Calculation and Implementation of Remaining Oxygen Supply Time This embodiment selects a certain model of compressed oxygen respirator, whose rated oxygen storage capacity in the airbag is L. 额 =800mL, airbag replenishment valve opening threshold L 实 =200mL, the cylinder's rated working pressure is 30Mpa. One firefighter will be selected to conduct a rescue mission under a simulated disaster scenario. The specific implementation steps are as follows: Step 1: Multi-source data acquisition and preprocessing The following real-time data is collected through each module: Physiological parameters: Respiratory rate is collected via a physiological acquisition module. f =20 breaths / minute, expiratory volume (L) 呼 =1000mL / time, inspiratory volume L 吸 =1050mL / time; Gas composition: Exhaled gas contains β%=5% carbon dioxide and α%=16% oxygen; Equipment pressure: The pressure after the gas cylinder supplies air to the airbag is currently P1=25Mpa, the pressure after the last air supply is P0=24.9Mpa, and the air supply time is T=2s, which is collected by the environmental parameter acquisition module. Air supply rate: The compressed air cylinder continuously supplies air to the airbag at a rate of 1.6 L / min; Drug weight: The current drug weight m1 = 805g and the previous weight m0 = 800g are collected by the drug monitoring module; After compensation for ambient temperature, the pressure parameters showed no deviation; after using a sliding window filter with 5 acquisition cycles, the physiological parameters showed no abnormal values.

[0017] Step 2: Real-time oxygen consumption calculation 1. Calculate the amount of oxygen consumed in one breath: O 单次 = L 吸 -(1-β%)×L 呼 =1050-(1-7%)×1000=120mL / time; 2. Calculate real-time oxygen consumption: V 耗氧 =120mL / time × 20 times / minute = 2400mL / min.

[0018] Step 3: Calculation and determination of remaining protection time 1. Determine the gas supply mode: V 补气 (1600 mL / min) < V 耗氧 (2400 mL / min), which meets the judgment condition of condition (2); 2. Calculate the rate of change of gas in the airbag and the replenishment interval: The net rate of airbag gas consumption is: [L] 吸 -(1- β %)×L 呼 ]× f -V 补气 =2400-1600=800mL / min.

[0019] Supply valve opening interval 45 seconds later, the airbag automatic replenishment valve opened, and the air cylinder replenished the airbag.

[0020] 3. Calculate the remaining number of fill operations N. calculate Rounding down gives 250; 4. Calculate the final remaining protection time: The remaining protection time is 250 × (0.75 + 2 / 60) ≈ 250 × 0.783 = 195.75 minutes.

[0021] Step 4: Early Warning Feedback The system's core processing module calculates the remaining time to be 195.75 minutes. When the model calculates that the remaining oxygen supply time of the compressed oxygen respirator is less than 20 minutes, the feedback warning module will trigger a level two warning, issuing a continuous beeping sound and a constantly lit red light signal via an audible and visual alarm.

[0022] This invention fully integrates multiple dimensions of parameters, including physiology, equipment, environment, and pharmaceuticals, breaking through the limitations of existing technologies that rely solely on cylinder pressure. It combines the core working principle of compressed oxygen breathing apparatus to build a model that dynamically adapts to changes in firefighters' work intensity, significantly improving prediction accuracy.

[0023] By collecting real-time physiological parameters such as firefighters' breathing rate, breathing volume, and heart rate, the system accurately calculates real-time oxygen consumption. When firefighters engage in high-intensity operations that cause a sudden increase in oxygen consumption, the system can dynamically adapt to the intensity of the operation and quickly recalculate the remaining time, realizing dynamic iteration of the oxygen consumption model and ensuring the real-time and accuracy of remaining time monitoring.

[0024] By fully considering the workflow of the compressed oxygen respirator, the oxygen replenishment logic of the air bag, the change of gas cylinder replenishment pressure and replenishment time are linked to ensure that the remaining time calculation process is highly consistent with the actual oxygen supply process of the equipment.

[0025] A sliding window filtering method is used to filter respiratory parameters, effectively eliminating the impact of instantaneous abnormal values ​​such as coughing and deep breathing on the monitoring results. At the same time, the environmental parameter acquisition module performs temperature compensation on pressure parameters to eliminate the error of pressure monitoring caused by changes in ambient temperature, ensuring the monitoring stability and data accuracy of the system in complex rescue environments.

[0026] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for real-time monitoring of the remaining time of a compressed oxygen respirator, comprising the following steps: Real-time acquisition of multi-source data: Obtain the firefighter's breathing rate f (breaths / minute), expiratory volume (L) 呼 (mL / time), inspiratory volume (L) 吸 (mL / time), and satisfying the inspiratory volume L 吸 > expiratory volume (L) 呼 ; Exhaled gas composition parameters: oxygen content α% and carbon dioxide content β% in exhaled gas. Equipment operating parameters: Cylinder pressure P1 (MPa) when the automatic replenishment valve of the compressed oxygen respirator's air bag is currently open, cylinder pressure P0 (MPa) when the automatic replenishment valve of the compressed oxygen respirator's air bag was last opened, replenishment valve opening time T (min), and the rate at which the compressed oxygen cylinder continuously replenishes air to the air bag V. 补气 (mL / min); Airbag status parameters: Gas volume (L) in the airbag when the automatic replenishment valve of the compressed oxygen respirator airbag is open. 实 (mL), the rated oxygen capacity (L) when the airbag is fully inflated. 额 (mL); Time parameter: Sensor signal acquisition time interval Δt (min); Calculate real-time oxygen consumption: based on the amount of oxygen consumed from the airbag during a firefighter's single breath. 单次 = L 吸 -(1- β %)×L 呼 ; And respiratory rate f, to calculate the firefighter's real-time oxygen consumption V. 耗氧 =[L 吸 -(1- β %)×L 呼 ]× f ; Determine the number of refill cycles: Monitor the pressure value P of the oxygen cylinder in the compressed oxygen respirator before and after refilling the air bag using a pressure sensor. i (MPa) and P i+1 (MPa), calculate the maximum number of times N can be replenished to the air bag from the current compressed oxygen respirator cylinder. ,in, i This indicates the number of times the oxygen cylinder of the compressed oxygen respirator replenishes the air bag; Calculate the remaining protection time: When V 补气 ≥V 耗氧 At that time, the remaining protection time t 剩余 The calculation formula is: t 剩余 = + ,in, f 1 represents the sampling frequency of the pressure sensor; When V 补气 <V 耗氧 At that time, the remaining protection time t 剩余 The calculation formula is: t 剩余 = 。 2. The method for real-time monitoring of the remaining time of a compressed oxygen respirator according to claim 1, characterized in that: The multi-source data also includes the current weight m1 (g) of the agent in the compressed oxygen respirator and the previous weight m0 (g). When m1 ≤ m0, an agent leakage alarm signal is triggered.

3. The method for real-time monitoring of the remaining time of a compressed oxygen respirator according to claim 1, characterized in that: The collected respiratory rate, expiratory volume, and inspiratory volume parameters were filtered using a sliding window filtering method to remove transient abnormal values ​​caused by coughing and deep breathing.

4. The method for real-time monitoring of the remaining time of a compressed oxygen respirator according to claim 1, characterized in that: The steps of obtaining the carbon dioxide and oxygen content in exhaled gas further include real-time monitoring of gas sensor data to help verify the accuracy of the oxygen consumption model.

5. A real-time monitoring and alarm system for the remaining time of a compressed oxygen respirator, characterized in that, include: The physiological data acquisition module is used to collect firefighters' heart rate, blood oxygen, respiratory rate, and rescue operation posture in real time. An environmental parameter acquisition module is connected in series at the outlet of the compressed oxygen cylinder to collect cylinder pressure and ambient temperature changes in real time and perform temperature compensation. The drug monitoring module is used to collect the current weight and previous weight of the drug in real time and monitor the drug consumption rate. The core processing module establishes a data connection with each signal acquisition module, has a built-in real-time oxygen consumption fusion model and dynamic iterative correction algorithm, is used to execute the steps of any of the above methods, output the remaining duration prediction value and warning signal, and has data storage function. The feedback and early warning module issues alarm information of corresponding levels based on the analysis results; The human-computer interaction module is used to display information such as remaining time, cylinder pressure, and physiological parameters, and to receive warning signals and activate corresponding alarm levels. Data transmission module: Used for data interaction with the rear command platform.

6. The real-time monitoring and alarm system for the remaining time of a compressed oxygen respirator according to claim 5, characterized in that: The physiological acquisition module further includes a heart rate sensor and a blood oxygen sensor, and the environmental parameter acquisition module further includes an algorithm unit for temperature compensation of pressure parameters.

7. The real-time monitoring and alarm system for the remaining time of a compressed oxygen respirator according to claim 5, characterized in that: The feedback warning module is configured to trigger a tiered warning, including audible and visual alarms, when the calculated remaining protection time is lower than a preset threshold.

8. The real-time monitoring and alarm system for the remaining time of a compressed oxygen respirator according to claim 5, characterized in that: The core processing module has a data storage function, which is used to record historical monitoring data and operation process information.

9. The application of the method according to any one of claims 1 to 4 in a positive pressure compressed oxygen respirator, the compressed oxygen respirator comprising a cyclic working circuit in which a reagent absorbs carbon dioxide and replenishes oxygen to an air bag through a compressed gas cylinder.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1 to 4.

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