An automated blood gas injection device and its positioning method based on vision and pressure sensing

Abstract

This invention relates to an automated blood gas sampling device and its positioning method based on vision and pressure sensing, belonging to the field of medical device technology, and solves the problems of low efficiency and poor accuracy in arterial blood gas collection in existing technologies. This invention provides an automated blood gas sampling device based on vision and pressure sensing, including a pressure-sensitive probe, a pressure-sensitive puncture needle assembly, a camera, and a needle insertion / retraction mechanism. The pressure-sensitive probe is used to sense the pulse to determine the location of the artery, the camera is used to monitor the blood return status of the pressure-sensitive puncture needle assembly, and the needle insertion / retraction mechanism performs needle insertion or withdrawal operations according to the blood return status and the location of the artery. This invention has pulse sensing capabilities in multiple directions, allowing the pressure-sensitive probe to sense pulses in multiple locations, improving the accuracy of arterial vessel positioning. Furthermore, by amplifying the signal from the pressure-sensitive unit, the precise positioning of the vessel is further achieved, improving the success rate of arterial blood gas puncture.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an automatic blood gas puncture device and its positioning method based on vision and pressure sensing. Background Technology

[0002] Arterial blood gas analysis is frequently required in clinical diagnosis and treatment. This test is used to determine whether a patient has acid-base imbalance, electrolyte disturbance, respiratory failure, etc., and is of great significance for clinical diagnosis, especially for the rescue of critically ill patients. In clinical practice, medical staff need to perform a large number of arterial blood gas collection procedures. Currently, the method of arterial blood gas collection mainly relies on the clinical experience of medical staff. The medical staff manually palpates the patient's arterial pulse at the point where it is most prominent, which is designated as the arterial puncture point. Then, the syringe is held at a 45-60 degree angle or perpendicular to the skin and inserted. When red liquid is seen splashing into the needle tip, the puncture is considered successful. About 1-2 ml of arterial blood is drawn and then connected to an arterial blood gas analyzer for measurement and analysis.

[0003] However, due to objective factors such as low blood volume and weak arterial pulsation in critically ill patients; poor vascular conditions, arteriosclerosis and stenosis in patients with chronic cardiovascular diseases; and insufficient operating experience of some medical staff, this procedure has a low success rate or incidents of accidental puncture into veins. This not only increases the cost of skills training for medical staff, but also easily leads to unnecessary doctor-patient conflicts in clinical practice. At the same time, the accuracy of arterial positioning is also poor. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide an automatic blood gas collection device and its positioning method based on vision and pressure sensing, in order to solve the problems of low efficiency and poor accuracy of existing arterial blood gas collection.

[0005] On one hand, the present invention provides an automatic blood gas injection device based on vision and pressure sensing, including a pressure-sensitive probe, a pressure-sensitive puncture needle assembly, a camera, and a needle insertion / retraction mechanism. The pressure-sensitive probe is used to sense the pulse to determine the location of the artery, the camera is used to monitor the blood return status of the pressure-sensitive puncture needle assembly, and the needle insertion / retraction mechanism performs needle withdrawal or needle insertion operations according to the blood return status and the location of the artery.

[0006] Furthermore, the pressure-sensitive probe includes a housing and a plurality of first pressure-sensitive sensors, the plurality of first pressure-sensitive sensors being disposed at the bottom of the housing.

[0007] Furthermore, the pressure-sensitive puncture needle assembly includes a puncture needle and a puncture needle clamp, with the upper end of the puncture needle fixedly connected to the lower part of the puncture needle clamp.

[0008] Furthermore, it also includes a first height adjustment mechanism for adjusting the height of the pressure-sensitive puncture needle assembly.

[0009] Furthermore, the first height adjustment mechanism includes a second mounting base, a second motor, a second lead screw, and a second slider. The second lead screw is rotatably connected to the second mounting base, the second slider is threadedly connected to the second lead screw, and the second motor drives the second lead screw to rotate.

[0010] Furthermore, the second mounting base is located on the back of the mounting box, and the pressure-sensitive puncture needle assembly is connected to the second slider.

[0011] Furthermore, it also includes a second height adjustment mechanism for adjusting the height of the pressure-sensitive probe.

[0012] Furthermore, the needle advance / retreat mechanism is connected to the pressure-sensitive puncture needle assembly and drives the puncture needle to advance or retract.

[0013] Furthermore, the tip of the puncture needle faces the center of the bottom of the placement box.

[0014] On the other hand, the present invention provides a positioning method for the above-mentioned automatic blood gas puncture device based on vision and pressure sensing, characterized in that the steps include:

[0015] Step S1: Depress the pressure-sensitive probe into contact with the skin, and ensure that the signal strength of K consecutive probes is greater than a given threshold N. thd1 ;

[0016] Step S2: After reaching the given threshold, stop the pressure probe from descending and start continuous signal acquisition.

[0017] Step S3: Perform generalized Laplace amplification processing on the signal to obtain the artery location.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] (1) The bottom of the pressure-sensitive probe of the present invention is provided with both a fixed first pressure-sensitive sensor and a movable sensing element. The movable sensing element has pulse sensing function in at least two directions, so that the pressure-sensitive probe can sense pulse in multiple directions, thereby improving the accuracy of arterial blood vessel positioning.

[0020] (2) The pressure-sensitive puncture needle assembly of the present invention includes a puncture needle and a puncture needle clamp. A third pressure-sensitive sensor is provided on the upper part of the puncture needle clamp, which can transmit the resistance encountered when inserting the needle at any time, thereby determining whether the needle has successfully entered the artery.

[0021] (3) The present invention is provided with an angle adjustment mechanism, an arc track on the roller shaft, a connecting column on the swing arm frame, the connecting column cooperates with the arc track and can move within the arc track, the roller shaft rotates, drives the swing arm frame to swing, and then drives the pressure-sensitive puncture needle assembly connected to the swing arm frame to swing, thereby realizing the adjustment of the tilt angle of the puncture needle.

[0022] (4) By amplifying the signal of the pressure-sensitive unit of the pressure-sensitive probe, the present invention achieves precise positioning of blood vessels, which can improve the success rate of arterial blood gas puncture, reduce unsatisfactory puncture results caused by factors such as poor vascular conditions of patients and lack of clinical experience of medical staff, and reduce manpower training and operation costs.

[0023] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from the description and drawings, which are particularly pointed out. Attached Figure Description

[0024] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0025] Figure 1 A schematic diagram of the overall structure of the automatic blood gas ligation device in a specific embodiment (I);

[0026] Figure 2 A schematic diagram (II) of the overall structure of the automatic blood gas ligation device according to a specific embodiment;

[0027] Figure 3 This is a schematic diagram of the structure of a pressure-sensitive probe without a cover plate according to a specific embodiment (I);

[0028] Figure 4 This is a schematic diagram (II) of the structure of a pressure-sensitive probe without a cover plate according to a specific embodiment;

[0029] Figure 5 A schematic diagram of the movable sensing element in a specific embodiment (I);

[0030] Figure 6 A schematic diagram (II) of the movable sensing element in a specific embodiment;

[0031] Figure 7 This is a schematic diagram of the structure of the first slider in a specific embodiment;

[0032] Figure 8 This is a schematic diagram of the connecting block in a specific embodiment;

[0033] Figure 9 A schematic diagram (I) of the connection structure between the puncture needle clamp and the first mounting base in a specific embodiment;

[0034] Figure 10 Schematic diagram (II) of the connection structure between the puncture needle clamp and the first mounting base in a specific embodiment;

[0035] Figure 11 This is a schematic diagram of the puncture needle in a specific embodiment;

[0036] Figure 12 This is a schematic diagram of the connection structure of the pressure-sensitive puncture needle assembly, the first height adjustment mechanism, the angle adjustment mechanism, and the needle advance / retract mechanism in a specific embodiment.

[0037] Figure 13 This is a schematic diagram of the structure of the second slider in a specific embodiment;

[0038] Figure 14 This is a schematic diagram of the swing frame in a specific embodiment;

[0039] Figure 15 This is a schematic diagram of the roller shaft in a specific embodiment;

[0040] Figure 16 This is a schematic diagram of the connecting rod in a specific embodiment;

[0041] Figure 17 This is a schematic diagram illustrating the acquisition of a 3-second signal in a specific embodiment.

[0042] Figure 18 This is a magnified schematic diagram of the signal in a specific embodiment.

[0043] Figure label:

[0044] 100-Pressure sensor; 101-Placement box; 102-Upper cover plate; 103-Lower cover plate; 104-First pressure sensor; 105-Modible sensing element; 106-Second pressure sensor; 107-Sliding seat; 108-First lead screw; 109-First motor; 110-Connecting rod; 111-First slider; 112-First partition; 113-Second partition; 114-Third partition; 115-Blind hole; 116-First threaded hole; 117-First slide groove; 118-First slide rail; 119-Connecting block; 120-Third threaded hole; 121-Third slide groove;

[0045] 200-Pressure-sensitive puncture needle assembly; 201-Puncture needle; 202-Puncture needle clamp; 203-First mounting base; 204-Third pressure-sensitive sensor;

[0046] 300-camera;

[0047] 400-First height adjustment mechanism; 401-Second mounting base; 402-Second motor; 403-Second lead screw; 404-Second slider; 405-Second slide rail; 406-Second slide groove; 407-Second threaded hole; 408-First connecting plate; 409-Second connecting plate; 410-Through hole;

[0048] 500 - Angle adjustment mechanism; 501 - Roller shaft; 502 - Third motor; 503 - Swing rod frame; 504 - Connecting rod; 505 - Support rod; 506 - Third connecting plate; 507 - Fourth connecting plate; 508 - Connecting column; 509 - Arc track;

[0049] 600 - Second height adjustment mechanism; 601 - Third mounting base; 602 - Fourth motor; 603 - Third lead screw; 604 - Third slide rail; 605 - Guide rod;

[0050] 700 - Needle advance / retract mechanism; 701 - Fourth mounting base; 702 - Fifth motor; 703 - Fourth lead screw; 704 - Third slider. Detailed Implementation

[0051] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0052] Example 1

[0053] A specific embodiment of the present invention, such as Figures 1-16 As shown, an automatic blood gas injection device based on vision and pressure sensing (hereinafter referred to as the automatic blood gas injection device) is disclosed. Figure 1 and Figure 2 As shown, the automatic blood gas puncture device includes a pressure-sensitive probe 100, a pressure-sensitive puncture needle assembly 200, a camera 300, a needle insertion / retraction mechanism 700, and a control unit. The pressure-sensitive probe 100 is used to sense the pulse to determine the location of the artery. The needle insertion / retraction mechanism 700 performs a needle insertion operation based on the artery location sensed by the pressure-sensitive probe 100. The camera 300 is used to monitor the blood return status of the pressure-sensitive puncture needle assembly 200 and feed back the blood return status to the control unit. The control unit issues a needle withdrawal or insertion command to the needle insertion / retraction mechanism 700 based on the blood return status and the artery location.

[0054] The pressure-sensitive probe 100 includes a housing 101, an upper cover 102, and a lower cover 103. Both the upper cover 102 and the lower cover 103 cover the housing 101. One side of the upper cover 102 is hinged to the housing 101, and the other side (opposite to the hinged side) is snapped onto or locked to the housing 101. The upper cover 102 can be opened. The lower cover 103 is made of transparent material. For example, the lower cover 103 is made of acrylic sheet and is connected to the housing 101 by screws. Generally, the lower cover 103 is not opened, and the lower area inside the housing 101 can be observed through the transparent lower cover 103.

[0055] In order to sense the pulse, such as Figure 3 and Figure 4 As shown, the pressure-sensitive probe 100 also includes a plurality of first pressure-sensitive sensors 104, which are disposed at the bottom of the housing 101 and used to contact human skin to sense pulse. Preferably, the first pressure-sensitive sensors 104 are arranged in two rows, with a plurality of first pressure-sensitive sensors 104 in each row. In this embodiment, the first pressure-sensitive sensors 104 are arranged in two rows, with nine sensors in each row.

[0056] To achieve multi-directional pulse perception and ensure accuracy, combined with Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the pressure probe 100 also includes multiple movable sensing elements 105. Each movable sensing element 105 includes a second pressure sensor 106 and a sliding base 107. The second pressure sensor 106 is disposed on the sliding base 107, and a second pressure sensor 106 is provided on both the bottom and one side of the sliding base 107. The second pressure sensor 106 on the side faces the center of the bottom of the mounting box 101. Preferably, there are four movable sensing elements 105.

[0057] In this embodiment, a first pressure sensor 104 and a second pressure sensor 106 are provided at the bottom of the housing 101. The second pressure sensor 106 can measure pulses in directions different from those of the first pressure sensor 104, so that the pressure probe 100 can obtain multiple directional pulses and thus accurately determine the location of the artery.

[0058] To achieve the extension and retraction of the movable sensing element 105, such as Figure 3 and Figure 4 As shown, the pressure sensor 100 also includes a first lead screw 108, a first motor 109, a connecting rod 110, and a first slider 111. Each movable sensing element 105 corresponds to a set of the first lead screw 108, first motor 109, connecting rod 110, and first slider 111. The mounting box 101 has three partitions parallel to the bottom of the mounting box 101, namely the first partition 112, the second partition 113, and the third partition 114.

[0059] Combination Figure 3 , Figure 4 and Figure 7 As shown, the first slider 111 has a blind hole 115, a first threaded hole 116, and a first groove 117. The side wall of the mounting box 101 has a first slide rail 118 that mates with the first groove 117. The first slide rail 118 is located between the second partition 113 and the third partition 114, and is perpendicular to the second partition 113. Figures 3-7 As shown, one end of the connecting rod 110 is connected to the top of the sliding seat 107, and the other end passes through the first partition 112 and the second partition 113 and is connected to the blind hole 115 of the first slider 111. The first lead screw 108 is connected to the first threaded hole 116 of the first slider 111. The two ends of the first lead screw 108 are rotatably connected to the second partition 113 and the third partition 114 respectively. The first motor 109 is placed on the third partition 114 and connected to the first lead screw 108 to provide power to the first lead screw 108.

[0060] In this embodiment, the first motor 109 drives the first lead screw 108 to rotate. Since the first slider 111 is threadedly connected to the first lead screw 108 and cooperates with the side wall slide rail of the mounting box 101, the rotational freedom of the first slider 111 is restricted. The first slider 111 moves along the first slide rail 118 between the second partition 113 and the third partition 114, thereby driving the extension and retraction of the sliding seat 107.

[0061] It should be noted that the extension and retraction of the movable sensing element 105 can also be achieved through hydraulic or pneumatic transmission.

[0062] like Figure 12 As shown, the pressure-sensitive puncture needle assembly 200 includes a puncture needle 201, a puncture needle holder 202, and a first mounting base 203, combined with... Figure 9 , Figure 10 and Figure 11 As shown, the upper end of the puncture needle 201 is connected to the lower part of the puncture needle clamp 202. The upper part of the puncture needle clamp 202 is provided with a third pressure sensor 204, which is located between the first mounting base 203 and the puncture needle clamp 202.

[0063] In this embodiment, when the puncture needle 201 pierces the skin, the third pressure sensor 204 can transmit the resistance encountered when the needle is inserted at any time. During normal puncture, the pressure will not change suddenly. When it enters the artery, there will be an impact response where the pressure suddenly decreases significantly. This can be used to determine whether the needle has successfully entered the artery.

[0064] Considering that the position of the pressure-sensitive puncture needle assembly 200 may need adjustment, the automatic blood gas puncture device also includes a first height adjustment mechanism 400, such as... Figure 12 and Figure 13As shown, the first height adjustment mechanism 400 includes a second mounting base 401, a second motor 402, a second lead screw 403, and a second slider 404. The second mounting base 401 is located on the rear side of the mounting box 101. A second slide rail 405 is provided on the second mounting base 401, parallel to the first slide rail 118. The second slider 404 has a second sliding groove 406 that mates with the second slide rail 405. Preferably, two second slide rails 405 are provided. The second slider 404 has a second threaded hole 407 that mates with the second lead screw 403. The second lead screw 403 is rotatably connected to the second mounting base 401. The second motor 402 is connected to the second lead screw 403, providing power for its rotation. The pressure-sensitive puncture needle assembly 200 is connected to the second slider 404.

[0065] In this embodiment, the second motor 402 drives the second lead screw 403 to rotate. Since the second slider 404 is threadedly connected to the second lead screw 403 and cooperates with the slide rail groove of the second mounting base 401, the second lead screw 403 drives the second slider 404 to slide along the second slide rail 405, thereby driving the pressure-sensitive puncture needle assembly 200 to move up and down.

[0066] The puncture needle 201 can be inserted vertically or at an angle, with an angled insertion being preferred. To allow for fine adjustment of the insertion angle of the puncture needle 201, the automatic blood gas puncture device also includes an angle adjustment mechanism 500. It should be noted that vertical insertion means that the puncture needle 201 is inserted perpendicular to the horizontal plane when the arm is flat.

[0067] like Figure 12 and Figure 16 As shown, the angle adjustment mechanism 500 includes a roller shaft 501, a third motor 502, a swing arm frame 503, and a connecting rod 504. The second slider 404 is provided with a first connecting plate 408 and a second connecting plate 409. The first connecting plate 408 and the second connecting plate 409 are parallel and perpendicular to the second slide rail 405. The two ends of the roller shaft 501 are rotatably connected to the first connecting plate 408 and the second connecting plate 409, respectively. The third motor 502 is connected to one end of the roller shaft 501 to provide power to the roller shaft 501.

[0068] like Figure 14 , Figure 15 and Figure 16As shown, the swing arm frame 503 includes a support rod 505, a third connecting plate 506, and a fourth connecting plate 507. One end of the support rod 505 is connected to the third connecting plate 506, and the other end of the support rod 505 is provided with a connecting post 508. The other end of the third connecting plate 506 is perpendicularly connected to one end of the fourth connecting plate 507. The connecting end of the support rod 505 and the third connecting plate 506 is hinged to one end of the connecting rod 504. The other end of the connecting rod 504 is fixed to the second slider 404. The roller shaft 501 is provided with an arc-shaped track 509. The connecting post 508 cooperates with the arc-shaped track 509 and can move within the arc-shaped track 509.

[0069] When the third motor 502 drives the roller 501 to rotate, the connecting column 508 cooperates with the arc track 509, which will drive the swing arm frame 503 to rotate in the vertical plane. The fourth connecting plate 507 is used to connect the pressure-sensitive puncture needle assembly 200, thereby realizing the adjustment of the angle of the puncture needle 201.

[0070] It is worth noting that the hinge position between the swing arm frame 503 and the connecting rod 504 has sufficient damping to ensure that the swing arm frame 503 will not rotate due to the weight of the components mounted on it when the roller shaft 501 is not rotating. Understandably, the components mounted on the fourth connecting plate 507 of the swing arm frame 503 are made of lightweight materials to reduce the weight of the components connected by the fourth connecting plate 507 and prevent the swing arm frame 503 from rotating when the roller shaft 501 is not rotating.

[0071] To facilitate confirmation of successful blood return, the camera 300 is mounted on the first mounting base 203 and faces the upper part of the puncture needle clamp 202 to capture images. Since the tubing connected to the upper end of the puncture needle 201 passes through the hole connecting the upper and lower parts of the puncture needle clamp 202, the camera 300 can capture images of the blood return status in the tubing.

[0072] To achieve vertical movement of the pressure-sensitive probe 100 while ensuring the stability of the connection of the pressure-sensitive puncture needle assembly 200, such as Figure 1 and Figure 2 As shown, the automatic blood-gas ligation device also includes a second height adjustment mechanism 600. The second height adjustment mechanism 600 includes a third mounting base 601, a fourth motor 602, and a third lead screw 603. The third mounting base 601 is provided with a third slide rail 604, such as... Figure 8 As shown, the side of the mounting box 101 is provided with a connecting block 119. The connecting block 119 is provided with a third threaded hole 120 that mates with the third lead screw 603, and a third sliding groove 121 that mates with the third slide rail 604. The axes of the third sliding groove 121 and the third threaded hole 120 are both parallel to the first slide rail 118. Driven by the fourth motor 602, the third lead screw 603 rotates on the third mounting base 601, thereby driving the pressure sensor 100 to move up and down.

[0073] To facilitate the insertion of the puncture needle 201, the automatic blood gas ligation device also includes a needle advance / retract mechanism 700, such as... Figure 12 As shown, the needle advance / retreat mechanism 700 includes a fourth mounting base 701, a fifth motor 702, a fourth lead screw 703, and a third slider 704. The fourth mounting base 701 is connected to the fourth connecting plate 507, the third slider 704 is threadedly connected to the fourth mounting base 701, and the first mounting base 203 is connected to the third slider 704. The fifth motor 702 drives the fourth lead screw 703 to rotate, thereby driving the first mounting base 203 to move along the direction of the fourth lead screw 703, and further driving the puncture needle 201 to advance or retreat.

[0074] It should be noted that the fourth connecting plate 507 is tilted, so that after the pressure-sensitive puncture needle assembly 200 is connected to the needle advance and retraction mechanism 700 mounted on it, the puncture needle 201 is also tilted and points to the center of the bottom of the placement box 101, that is, the puncture needle 201 points to the position of the artery blood vessel sensed by the pressure-sensitive sensor.

[0075] Considering that the first height adjustment mechanism 400, the angle adjustment mechanism 500, and the pressure-sensitive puncture needle assembly 200 are all located on the rear side of the mounting box 101, in order to ensure the stability of the structure, such as Figure 1 and Figure 2 As shown, the second height adjustment mechanism 600 also includes a guide rod 605, which is parallel to the third lead screw 603, and both ends are connected to the third mounting base 601, as shown. Figure 13 As shown, the second slider 404 is provided with a through hole 410 that mates with the guide rod 605.

[0076] Example 2

[0077] Because arteries have relatively strong pulses, they exhibit periodic fluctuations in pressure signals when detected by pressure sensors. Therefore, the location of arteries can be confirmed by collecting these periodic fluctuations in pressure signals, achieving precise localization.

[0078] Another specific embodiment of the present invention, such as Figures 1-18 As shown, a positioning method for an automatic blood gas puncture device based on vision and pressure sensing is disclosed. The automatic blood gas puncture device based on vision and pressure sensing from Example 1 is used for precise positioning. For ease of explanation, the pressure-sensitive unit at the bottom of the pressure-sensitive probe 100 is encoded as shown in the table below:

[0079] a1 a2 a3 a4 <![CDATA[a5(L1)]]> a6 <![CDATA[a7(R1)]]> a8 a9 a10 a11 b1 b2 b3 b4 <![CDATA[b5(L2)]]> b6 <![CDATA[b7(R2)]]> b8 b9 b10 b11

[0080] The steps for precise positioning using an automatic blood gas puncture device include:

[0081] Step S1: The pressure-sensitive probe 100 is lowered to contact the skin, and it is ensured that the signal strength of K consecutive probes is greater than the given threshold N. thd1 .

[0082] Step S2: After reaching the given threshold, stop the pressure probe 100 downward probe operation and start continuous signal acquisition.

[0083] Step S3: Process and analyze the signal to obtain a preliminary estimate of the artery location.

[0084] Step S3.1: Acquire a 3s signal, the signal is as follows: Figure 17 As shown.

[0085] Step S3.2: Perform generalized Laplace amplification on the signal.

[0086] Step S3.2.1: Taking a sampling frequency of 50Hz as an example, there are a total of 150 signal points in 3 seconds.

[0087] Step S3.2.2: Let the input data be x and the output data be y. Then y = [data from the first second to the first half second] + x [data from the second half second to the second second] - x [data from the first half second to the second half second]. Amplify the signal in x with a period around 1 second. The amplified signal is as follows: Figure 18 As shown.

[0088] Step S3.2.3: Take the difference between the maximum and minimum values ​​of the amplified signal as the signal strength at that point.

[0089] Step S3.3: After calculating the signal strength of all pressure-sensitive units (the pressure-sensitive sensors arranged in rows and columns at the bottom of the sensing probe 100), perform a comprehensive position determination.

[0090] Step S3.3.1: Take the maximum value of the amplified signal value calculated by the generalized Laplace in step S3.2 and denote it as V. max If the amplified signal at the maximum value position (i.e., along the length of the bottom of the placement box 101, directly opposite the front of the placement box 101, with left and right sides corresponding to the left and right sides of a person) is greater than V max If the value is 2, then the corresponding position is included in the calculation; otherwise, the coarse location of the blood vessel in that row is recorded as the pressure-sensitive unit position corresponding to the maximum value.

[0091] Step S3.3.2: If adjacent pressure-sensitive units are involved in the calculation, the coarsely located blood vessel position is:

[0092]

[0093] Where Loc indicates that the location of the blood vessel deviates from V. max The distance to the right of the corresponding pressure-sensitive unit, V RThis indicates the pressure value of the pressure-sensitive unit on the right, V. L This indicates the pressure value of the pressure-sensitive unit on the left.

[0094] Step S3.3.3: Calculate the position Loc of the two rows of pressure-sensitive units respectively. a Loc b To determine the location and vector of the blood vessel, the following steps are performed.

[0095] Step S3.4: Move the pressure probe 100 upward to reduce the pressure on the pressure probe 100, ensuring that the artery position will not be changed due to excessive force in the following actions.

[0096] Step S3.5: Align the designated center point of the pressure-sensitive probe 100 (the center of the bottom of the mounting box 101) with the initially detected artery location, and press down on the pressure-sensitive probe 100 to ensure that the center point pressure is greater than the given threshold N. thd2 .

[0097] Step S3.6: The pressure-sensitive units (i.e., the four movable sensing elements 105) on both sides of the center point of the pressure-sensitive probe 100 are denoted as L1, L2, R1, and R2, respectively. The four movable sensing elements 105 continue to move downward to ensure that the pressure they sense is greater than the given threshold N. thd3 It serves to clamp and fix the artery.

[0098] Step S3.6.1: Analyze the periodic change intensity relationship of the signals of the two motion units (the second pressure-sensitive sensors 106 set on the side of the four movable sensing elements 105) to determine the force on the two motion units. This periodic analysis is the same as step S3.2.

[0099] Step S3.6.2: Combining the difference in force on both sides (i.e., the force on the second pressure-sensitive sensors 106 installed on the sides of the four movable sensors 105) and the force on the central probe (the second pressure-sensitive sensor 106 installed at the bottom of the four movable sensors 105), the final artery location is obtained. The specific determination formula is as follows:

[0100]

[0101] Where Loc represents the distance to the right of the blood vessel from the center, and V L1 V R1 V represents the axial force (i.e., vertical force) on the movable sensing element 105. L2 V R2 This indicates the radial force (i.e., the force perpendicular to the axial direction) on the movable sensing element 105.

[0102] In this embodiment, the precise location of blood vessels is achieved by amplifying the signal of the pressure-sensitive unit of the pressure-sensitive probe 100.

[0103] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic blood gas ligation device based on vision and pressure sensing, characterized in that, It includes a pressure-sensitive probe (100), a pressure-sensitive puncture needle assembly (200), a camera (300), and a needle insertion / retraction mechanism (700). The pressure-sensitive probe (100) is used to sense the pulse to determine the location of the artery. The camera (300) is used to monitor the blood return status of the pressure-sensitive puncture needle assembly (200). The needle insertion / retraction mechanism (700) performs needle insertion or withdrawal operations according to the blood return status and the location of the artery. The pressure-sensitive probe (100) includes a housing (101), a plurality of first pressure-sensitive sensors (104), and a plurality of movable sensing elements (105); the plurality of first pressure-sensitive sensors (104) are disposed at the bottom of the housing (101), and the first pressure-sensitive sensors (104) are used to contact human skin to sense pulse; the movable sensing element (105) includes a second pressure-sensitive sensor (106) and a sliding seat (107), the second pressure-sensitive sensor (106) is disposed on the sliding seat (107), and a second pressure-sensitive sensor (106) is provided on the bottom and one side of the sliding seat (107), the second pressure-sensitive sensor (106) on the side of the sliding seat (107) facing the middle of the bottom of the housing (101); by amplifying the signal of the pressure-sensitive unit of the pressure-sensitive probe (100), the precise determination of the blood vessel position is achieved.

2. The automatic blood gas ligation device based on vision and pressure sensing according to claim 1, characterized in that, The pressure-sensitive puncture needle assembly (200) includes a puncture needle (201) and a puncture needle clamp (202), with the upper end of the puncture needle (201) fixedly connected to the lower part of the puncture needle clamp (202).

3. The automatic blood gas ligation device based on vision and pressure sensing according to claim 1, characterized in that, It also includes a first height adjustment mechanism (400) for adjusting the height of the pressure-sensitive puncture needle assembly (200).

4. The automatic blood gas ligation device based on vision and pressure sensing according to claim 3, characterized in that, The first height adjustment mechanism (400) includes a second mounting base (401), a second motor (402), a second lead screw (403), and a second slider (404). The second lead screw (403) is rotatably connected to the second mounting base (401), and the second slider (404) is threadedly connected to the second lead screw (403). The second motor (402) drives the second lead screw (403) to rotate.

5. The automatic blood gas ligation device based on vision and pressure sensing according to claim 4, characterized in that, The second mounting base (401) is located on the back of the mounting box (101), and the pressure-sensitive puncture needle assembly (200) is connected to the second slider (404).

6. The automatic blood gas dispensing device based on vision and pressure sensing according to any one of claims 1-5, characterized in that, It also includes a second height adjustment mechanism (600) for adjusting the height of the pressure sensor (100).

7. The automatic blood gas ligation device based on vision and pressure sensing according to claim 2, characterized in that, The needle advance / retreat mechanism (700) is connected to the pressure-sensitive puncture needle assembly (200) and drives the puncture needle (201) to advance or retreat.

8. The automatic blood gas ligation device based on vision and pressure sensing according to claim 2, characterized in that, The tip of the puncture needle (201) faces the center of the bottom of the placement box (101).

9. A positioning method for an automatic blood gas puncture device based on vision and pressure sensing as described in any one of claims 1-8, characterized in that the steps include... include: Step S1: The pressure-sensitive probe (100) is lowered into contact with the skin, and it is ensured that the signal strength of K consecutive probes is greater than the given threshold N. thd1 ; Step S2: After reaching the given threshold, stop the downward probe operation of the pressure sensor (100) and perform continuous signal acquisition. Step S3: Perform generalized Laplace amplification processing on the signal to obtain the artery location.

Images