Breathing parameter measuring device and method

Abstract

The invention relates to a breathing parameter measuring device and method based on multi-parameter characteristics, and aims to realize accurate measurement of breathing frequency, breathing amplitude and breathing intensity at the same time. The device comprises a servo motor driving system, a double-shaft double-acting air cylinder system and a control system. According to the device, through cooperative work of the servo motor driving system and the double-shaft double-acting air cylinder system and precise control of the PLC and the proportional valve, the problems that a traditional respiration measuring device is low in precision and single in function are solved, and high calibration precision and adaptability are achieved. The breathing characteristics of different crowds can be adapted by adjusting the rotating radius of the L-shaped connecting rod and the stroke of the air cylinder.

Description

Technical Field

[0001] The present invention relates to the technical field of medical measurement, and particularly to a respiratory parameter measurement device and a measurement method. Background Art

[0002] Respiration is a key physiological process for human beings to maintain life, involving gas exchange to ensure oxygen supply and carbon dioxide excretion. The frequency, amplitude, and intensity of respiration are important parameters for evaluating respiratory function, and these parameters can be used as important reference indicators for the diagnosis of related diseases. For example, the condition of lung cancer patients can be analyzed through respiratory frequency and respiratory amplitude, and respiratory intensity is an important reference basis for airway obstruction and respiratory muscle fatigue.

[0003] In recent years, chronic respiratory diseases represented by chronic obstructive pulmonary disease, bronchial asthma, and lung cancer have become the fourth leading cause of death. The respiratory process will undergo various changes due to different physiological states, and various influencing factors can directly or indirectly affect the motor function of the respiratory system by acting on receptors such as the respiratory center and pulmonary stretch reflex. Therefore, respiratory system lesions are often accompanied by abnormal respiration, usually manifested as abnormalities in aspects such as respiratory frequency, amplitude, and intensity. The combination of these abnormal conditions may further form more complex respiratory abnormalities, leading to changes in the human respiratory state. For this reason, it is of great clinical significance to evaluate and measure the respiratory state through information such as respiratory frequency.

[0004] Currently, contact measurement techniques are mainly used clinically, and common methods include respiratory airflow detection, photoplethysmography, impedance respiratory monitoring, and transformer detection methods. The contact measurement method requires fixing or inserting specific equipment into the corresponding part of the body, resulting in low patient comfort and restrictions on the measurement population and the range of activities of the measured person. To improve the above drawbacks, related research is exploring non-contact respiratory measurement techniques, which can remotely monitor the respiratory condition without directly contacting the patient. The main techniques involved include: bio-radar method, face feature recognition-based method, infrared imaging technology, and radio microwave method, etc. The non-contact measurement method indicates the development direction of future respiratory measurement technology, but it has not been widely applied clinically due to defects in robustness and accuracy.

[0005] In addition, the above-mentioned techniques only measure the respiratory frequency and do not measure the respiratory amplitude and intensity. The respiratory amplitude is usually measured by the change in the circumference of the human chest wall with respiratory movement, or the change in the position of the diaphragm with respiratory movement can be obtained by calculating medical ultrasound images. Although the respiratory amplitude to a certain extent characterizes the respiratory intensity, it is not comprehensive. The strength of respiratory muscles such as the abdominal muscles, intercostal muscles, and diaphragm also reflects the respiratory intensity. So far, there has not been a device in this field that can comprehensively measure the respiratory state. Summary of the Invention

[0006] In view of the above deficiencies of the prior art, the present invention provides a respiratory parameter measurement device and a measurement method based on multi-parameter features, aiming to accurately measure respiratory frequency, respiratory amplitude, and respiratory intensity simultaneously. Through the collaborative work of the servo motor drive system and the double-acting double-axis cylinder system, combined with the precise control of the PLC controller and the proportional valve, the device solves the problems of low accuracy and single function of traditional respiratory measurement devices, and has high calibration accuracy and adaptability.

[0007] To achieve the above technical objectives, a first aspect of the present invention proposes a respiratory parameter measurement device, which includes a servo motor drive system, a double-acting double-axis cylinder system, and a control system. The servo motor drive system includes a motor driver, a servo motor, an L-shaped connecting rod, a push rod, and a chute mechanism connected in sequence; the double-acting double-axis cylinder system includes a double-acting double-axis adjustable stroke cylinder, a proportional valve, a solenoid valve, and a pressure sensor; the control system includes a PLC controller and a communication card. Among them,

[0008] One output end of the double-acting double-axis adjustable stroke cylinder is rigidly connected to the pressure sensor, and the other output end is rigidly connected to the slider in the chute mechanism; the front inlet and the return port of the double-acting double-axis adjustable stroke cylinder are connected to the proportional valve, and the solenoid valve is connected to the double-acting double-axis adjustable stroke cylinder to adjust the cylinder stroke; the proportional valve, the solenoid valve, the pressure sensor, the motor driver, and the communication card are all connected to the PLC controller.

[0009] Further, the pressure sensor contacts the human chest to collect pressure data; the communication card exchanges data with the outside of the measurement device. The communication card can realize the communication between the PLC controller and the outside world.

[0010] Further, the PLC controller and the communication card are also connected to a display, and both the motor driver and the communication card are connected to a power supply.

[0011] Further, the output shaft of the servo motor is vertically and rigidly connected to one branch of the L-shaped connecting rod, the other branch of the L-shaped connecting rod is rotatably connected to one end of the push rod, and the other end of the push rod is swingably connected to the slider. Through the connection of the L-shaped connecting rod, the push rod, and the chute slider, the rotational motion of the output shaft of the servo motor can be converted into a linear reciprocating motion of the slider in the chute. The rotational connection between the other branch and one end of the push rod includes, but is not limited to, coupling connection, ball joint connection, etc., and the swing connection between the other end of the push rod and the slider includes, but is not limited to, U-shaped hook connection, hinge connection, etc. Those skilled in the art can select appropriate connection methods according to needs.

[0012] Furthermore, the rotation radius of the L-shaped connecting rod connected to the output shaft of the servo motor is adjustable. The rotation radius can be adjusted by changing the position of the support rod connected to the push rod on the support rod connected to the output shaft of the servo motor. For example, the two support rods of the L-shaped connecting rod can be separated, and the rotation radius can be changed by means of pins, fastening nuts or plug-in structures, etc.

[0013] Furthermore, the PLC controller adjusts the rotation speed of the servo motor according to the breathing frequency; the proportional valve adjusts the intake and exhaust air pressures of the cylinder according to the instructions of the PLC controller to achieve dynamic calibration of the breathing intensity.

[0014] The second aspect of the present invention proposes a breathing parameter measurement method using the above-mentioned breathing parameter measurement device, and the method is used to measure the breathing frequency, breathing amplitude and / or breathing intensity.

[0015] Furthermore, the measurement of the breathing frequency includes: adjusting the rotation speed of the servo motor so that the rotation frequency of the servo motor is consistent with the human breathing frequency; the PLC controller controls the corresponding pause of the servo motor according to the pause time in the breathing cycle.

[0016] The pause time in the breathing cycle varies from person to person. For example, a normal person will pause for 1-2 seconds at the end of each inhalation and exhalation, but it is not limited thereto. Thus, the PLC controller controls the servo motor to make corresponding pauses during the breathing pause (for example, when the slider is at both ends of the stroke of the sliding groove).

[0017] Furthermore, the measurement of the breathing amplitude includes: adjusting the stroke of the double-acting adjustable stroke cylinder so that the cylinder stroke is consistent with the contraction amplitude of the human chest cavity.

[0018] The breathing amplitude is determined by the stroke of the cylinder, and the calculation formula is:

[0019] A = S exhale -S inhale (1)

[0020] where A is the breathing amplitude, S exhale is the cylinder position at the end of exhalation, and S inhale is the cylinder position at the end of inhalation.

[0021] Furthermore, the measurement of the breathing intensity includes: controlling the return force of the double-acting adjustable stroke cylinder through a pressure sensor and a proportional valve so that the return force is equal to the outward thrust of the human chest cavity during inhalation.

[0022] The calculation formula for the breathing intensity is:

[0023] F = (P 2 -P 1 ) × S + F sensor = Fcylinder +F sensor (2)

[0024] Among them, F is the breathing intensity, P 1 is the air pressure on one side of the cylinder connecting the slider (process air pressure (Pa)), P 2 is the air pressure on the side of the cylinder close to the human chest cavity (return air pressure (Pa)), S is the effective area of the piston (m 2 ), F cylinder is the return force of the cylinder (N), F sensor is the measured value of the pressure sensor.

[0025] In the technical solution of the present invention, the measurement of respiratory parameters based on multi-parameter characteristics is realized by the coordinated use of a proportional valve, a pressure sensor and a PLC controller. The proportional valve can be used to adjust the pressure or flow rate in the air chamber of the cylinder to achieve precise control; the pressure sensor can be used to monitor the motion state and load condition of the cylinder in real time; the PLC controller can be used to adjust the output of the proportional valve according to the sensor feedback signal to achieve closed-loop control.

[0026] In the technical solution of the present invention, the coordinated work of the proportional valve and the PLC controller is one of the core innovation points of the technical solution of the present invention. The control accuracy of the proportional valve can reach ±0.01 MPa, and it can realize the fine adjustment and precise control of the cylinder thrust. The specific control process is as follows:

[0027] Air pressure regulation: The PLC controller adjusts the air pressure of the proportional valve in real time according to the feedback of the pressure sensor, so that the return force of the cylinder is equal to the thrust of the chest cavity outward during human inspiration.

[0028] Dynamic calibration: During the measurement process, the PLC controller continuously adjusts the air pressure of the proportional valve to ensure that the measured value of the pressure sensor is close to 0, so as to realize the dynamic calibration of the breathing intensity.

[0029] Error compensation: Through the closed-loop control of the high-precision proportional valve and the PLC controller, the error in the measurement process can be effectively compensated, and the accuracy of the measurement result can be improved.

[0030] The measurement device and measurement method of the present invention have the following advantages compared with the prior art:

[0031] 1. Integrated design: Combining the servo motor drive system with the double-axis double-acting cylinder system realizes the synchronous measurement of respiratory frequency, respiratory amplitude and breathing intensity, overcoming the singularity of the existing measurement methods.

[0032] 2. High-precision calibration: Through the precise control of the PLC controller and the proportional valve, the dynamic calibration of respiratory parameters is realized.

[0033] 3. Wide adaptability: By adjusting the rotation radius of the L-shaped connecting rod and the stroke of the cylinder, it can adapt to the breathing characteristics of different people. Brief Description of the Drawings

[0034] Figure 1 It is a composition structure diagram of the breathing parameter measurement device described in an embodiment of the present invention.

[0035]

Description of the Reference Numerals

[0036] 1 - Servo motor; 2 - Motor driver; 3 - PLC controller; 4 - Communication card; 5 - Display; 6 - Power supply; 7 - Double-acting adjustable stroke cylinder; 71 - Front inlet; 72 - Return port; 8 - Proportional valve; 9 - Solenoid valve; 10 - Pressure sensor; 11 - L-shaped connecting rod; 12 - Push rod; 13 - Slide groove mechanism. Detailed Embodiment

[0037] In order to better understand the above technical solution, the exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

[0038] Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more clear and thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0039] In the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", "fixation" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In the description of this specification, the description of terms such as "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0041] Example 1

[0042] As Figure 1 shown, the composition structure diagram of the breathing parameter measurement device in an embodiment of the present invention is shown. The double-axis double-acting adjustable stroke cylinder used therein adopts the CMAJ series compact double-axis double-acting cylinder of SMC Corporation of Japan, with a cylinder diameter of 12 mm, which can be used for applications of stroke adjustment.

[0043] The measurement device includes a servo motor drive system (motor driver 2, servo motor 1, L-shaped connecting rod 11, push rod 12, and chute mechanism 13 connected in sequence), a double-axis double-acting cylinder system (including double-axis double-acting adjustable stroke cylinder 7, proportional valve 8, solenoid valve 9, and pressure sensor 10), and a control system (including PLC controller 3 and communication card 4).

[0044] The output end of the double-axis double-acting adjustable stroke cylinder 7 close to the human body is rigidly connected to the pressure sensor 10, and the other output end is rigidly connected to the slider in the chute mechanism 13; the front inlet 71 and the return port 72 of the double-axis double-acting adjustable stroke cylinder 7 are connected to the proportional valve 8, and the rate and amount of air intake and exhaust can be controlled through the proportional valve 8. The solenoid valve 9 is connected to the double-axis double-acting adjustable stroke cylinder 7 to cooperate with the adjustable rotation radius of the L-shaped connecting rod 11 to adjust the stroke of the cylinder 7; the proportional valve 8, solenoid valve 9, pressure sensor 10, motor driver 2, and communication card 4 are all connected to the PLC controller 3.

[0045] The PLC controller 3 and the communication card 4 are also connected to a display 5 for outputting the input and output instructions and data of the PLC controller 3 and the communication card 4; the motor driver 1 and the communication card 4 are both connected to the power supply 5.

[0046] Example 2

[0047] On the basis of Example 1, the output shaft of the servo motor 2 is vertically and rigidly connected (at the middle of the horizontal support rod) to a support rod (horizontal support rod) of the L-shaped connecting rod 11. The other support rod (vertical support rod) of the L-shaped connecting rod is rotatably connected (ball hinge connection) to one end of the push rod, and the other end of the push rod is swingably connected (U-shaped hook connection) to the slider in the chute mechanism 13. Through the connection of the L-shaped connecting rod 11, push rod 12, and chute mechanism 13, the rotational motion of the output shaft of the servo motor 2 can be converted into a linear reciprocating motion of the slider in the chute.

[0048] The rotation radius of the L-shaped connecting rod 11 connected to the output shaft of the servo motor 2 is adjustable. The two support rods of the L-shaped connecting rod 11 can be separated, and the rotation radius is adjusted by changing the position of the vertical support rod on the horizontal support rod. The position of the adjusted vertical support rod is fixed by a fastening nut to change the rotation radius of the L-shaped connecting rod 11, and the cylinder stroke is adjusted in cooperation with the solenoid valve 9.

[0049] The PLC controller 3 adjusts the rotational speed of the servo motor 1 according to the breathing frequency; the proportional valve 8 adjusts the intake and exhaust air pressures of the cylinder 7 according to the instructions of the PLC controller 3 to achieve dynamic calibration of the breathing intensity.

[0050] Embodiment 3

[0051] Based on Embodiment 2, the implementation steps of the breathing parameter measurement method are as follows.

[0052] Step 1: Device initialization

[0053] Start the servo motor drive system and the double-acting cylinder system with double shafts for initialization settings. Set the initial parameters of the PLC controller, including the motor rotational speed, the cylinder stroke, and the proportional valve air pressure.

[0054] Step 2: Respiratory rate measurement

[0055] Detect the breathing frequency of the human body through the pressure sensor 10 and transmit the data to the PLC controller 3. The PLC controller 3 adjusts the rotational speed of the servo motor 2 to be consistent with the breathing frequency (for example, keep the value of the pressure sensor at 0). During the pause time (1 - 2 seconds) of the breathing cycle, control the motor 2 to pause at the near rotation position and the far rotation position.

[0056] Step 3: Respiratory amplitude measurement

[0057] Connect the L-shaped connecting rod and the rigid push rod to convert the rotational motion of the output shaft of the servo motor 1 into a linear motion, and push the piston shaft of the cylinder 7 to reciprocate. By adjusting the stroke of the cylinder 7 and the rotation radius of the L-shaped connecting rod, make the stroke of the piston shaft consistent with the contraction amplitude of the human chest cavity.

[0058] Read the position data of the cylinder 7 through the PLC controller 3 and calculate the breathing amplitude:

[0059] A = S exhale - S inhale (1)

[0060] Where, A is the breathing amplitude, S exhale is the cylinder position at the end of exhalation, S inhale is the cylinder position at the end of inhalation.

[0061] Step 4: Respiratory intensity measurement

[0062] Fix the pressure sensor 10 at the end of the piston shaft on the side where the cylinder 7 contacts the human chest cavity, and detect the outward thrust of the chest cavity during human inhalation through the pressure sensor 10. The PLC controller 3 adjusts the air pressure of the proportional valve 8 according to the feedback of the pressure sensor 10, so that the return force of the cylinder 7 is equal to the chest cavity thrust. When the measured value of the pressure sensor is close to 0, record the return force of the cylinder at this time and calculate the breathing intensity:

[0063] F = F cylinder + F sensor (3)

[0064] where F is the breathing intensity, F cylinder is the return force of the cylinder (N), and F sensor is the measured value of the pressure sensor (for example, according to experience, F sensor is usually 0.1 N).

[0065] Step 5: Data display and storage

[0066] Display the measurement results (breathing frequency, breathing amplitude, and breathing intensity) on the screen of the display 5 and store them in the database for subsequent analysis.

[0067] Example 4

[0068] Based on Example 3, give the control program of the PLC controller. The following provides a pseudo-code implementation of the PLC controller by way of example:

[0069]

[0070]

[0071]

[0072]

[0073] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A respiratory parameter measuring device, characterized in that: The device includes a servo motor drive system, a double-axis double-acting cylinder system and a control system. The servo motor drive system includes a motor driver, a servo motor, an L-shaped connecting rod, a push rod and a slide mechanism connected in sequence; the double-axis double-acting cylinder system includes a double-axis double-acting adjustable range cylinder, a proportional valve, a solenoid valve and a pressure sensor; the control system includes a PLC controller and a communication card, wherein, One output end of the double-axis double-acting adjustable-range cylinder is rigidly connected to the pressure sensor, and the other output end is rigidly connected to the slider in the slide mechanism; the front inlet and return port of the double-axis double-acting adjustable-range cylinder are connected to the proportional valve, and the solenoid valve is connected to the double-axis double-acting adjustable-range cylinder to adjust the cylinder stroke; the proportional valve, solenoid valve, pressure sensor, motor driver and communication card are all connected to the PLC controller.

2. The respiratory parameter measurement device according to claim 1, characterized in that: The pressure sensor contacts the human chest to collect pressure data; the communication card exchanges data with the outside of the measuring device.

3. The respiratory parameter measurement device according to claim 1, characterized in that: The PLC controller and the communication card are also connected to a display, and the motor driver and the communication card are both connected to a power supply.

4. The respiratory parameter measurement device according to any one of claims 1 to 3, characterized in that: The output shaft of the servo motor is vertically rigidly connected to a support rod of the L-shaped connecting rod, the other support rod of the L-shaped connecting rod is rotationally connected to one end of the push rod, and the other end of the push rod is swingably connected to the slider.

5. The respiratory parameter measurement device according to any one of claims 1 to 3, characterized in that: The rotation radius of the L-shaped connecting rod connected to the output shaft of the servo motor is adjustable.

6. The respiratory parameter measurement device according to claim 1, characterized in that: The PLC controller adjusts the servo motor speed according to the breathing frequency; the proportional valve adjusts the intake and exhaust pressure of the cylinder according to the instructions of the PLC controller to achieve dynamic calibration of the breathing intensity.

7. A method for measuring breathing parameters using the breathing parameter measuring device according to any one of claims 1 to 6, characterized in that: The method is used to measure respiratory rate, respiratory amplitude and / or respiratory intensity.

8. The respiratory parameter measurement method according to claim 7, characterized in that: The measurement of the respiratory frequency includes: adjusting the rotation speed of the servo motor so that the rotation frequency of the servo motor is consistent with the respiratory frequency of the human body; and the PLC controller controls the servo motor to pause accordingly according to the pause time in the respiratory cycle.

9. The respiratory parameter measurement method according to claim 7, characterized in that: The measurement of the respiratory amplitude includes: adjusting the stroke of the double-axis double-acting adjustable-range cylinder so that the cylinder stroke is consistent with the contraction amplitude of the human chest cavity, The breathing amplitude is determined by the stroke of the cylinder and is calculated as: A=S exhale -S inhale (1) Where A is the respiratory amplitude, S exhale is the cylinder position at the end of exhalation, S inhale is the cylinder position at the end of inspiration.

10. The respiratory parameter measurement method according to claim 7, characterized in that: The measurement of the breathing intensity includes: controlling the return force of the double-axis double-acting adjustable-range cylinder through a pressure sensor and a proportional valve, so that the return force is equal to the outward thrust of the chest cavity when the human body inhales, The formula for calculating breathing intensity is: F=(P2-P1)×S+F sensor =F cylinder +F sensor (2) Among them, F is the breathing intensity, P1 is the process air pressure on the side of the cylinder connected to the slider, P2 is the return air pressure on the side of the cylinder close to the human chest cavity, S is the effective area of ​​the piston, and F cylinder is the cylinder return force, F sensor is the measured value of the pressure sensor.

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