Nerve monitoring trachea cannula and monitoring system

Abstract

The utility model discloses a nerve monitoring trachea cannula and a monitoring system, which comprise a trachea cannula body, an inflation cuff, an inflatable cuff inflation tube, an indication balloon and a trachea cannula joint, an electromyographic signal detection unit is arranged at a set distance of the inflation cuff far away from an insertion port end, and a contact electrode is used for indirectly transmitting nerve stimulation signals. Real-time monitoring of recurrent laryngeal nerves in a thyroid surgery is achieved, and nerve injury is avoided while the accuracy rate of a monitoring result is high; the curvature sensor is arranged in the trachea cannula body between the inflatable cuff and the electromyographic signal detection unit, so that the bending degree of the trachea cannula is monitored in real time, a doctor is assisted in catheter placement, and soft tissue injury is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of active medical equipment, and in particular relates to a nerve monitoring tracheal intubation and monitoring system. Background Art

[0002] In existing technologies, recurrent laryngeal nerve (RLN) injury is one of the most common and serious complications after thyroid surgery. Unilateral injury can cause hoarseness and voice weakness, while bilateral injury can cause aphonia, difficulty breathing, and even suffocation. Thyroid IONM (intraoperative neuromonitoring) technology has the ability to quickly locate the recurrent laryngeal nerve and identify anatomical variations. It can indicate risky operations, reduce the rate of nerve injury, and has become an effective auxiliary means of protecting the recurrent laryngeal nerve, especially in complex thyroid surgery. This technology mainly stimulates the recurrent laryngeal nerve to generate an action potential in the vocal cords it controls. When the surface electrode on the endotracheal tube contacts this potential, the signal is transmitted to the back-end monitoring equipment, which uses electromyography and prompt sounds to assist doctors in determining whether the recurrent laryngeal nerve is damaged.

[0003] The types of surface electrodes on the market can be divided into three categories: 1. Pairs of exposed metal wires are used as surface electrodes, embedded in the endotracheal tube body, and the electrode wires are connected at the entrance hole, and then connected to the monitoring equipment at the back end. The metal wires used in this technology are exposed in the vocal cord area, which poses a risk of injuring the patient's vocal cord tissue; in addition, because the material is relatively hard, the surface electrodes and the tube body or vocal cords may not fit properly during the bending process of the tube body, which may lead to erroneous signals, unstable signals, or no signals. 2. A conductive coating with a certain width and length is directly coated on the outer wall of the tube body, which serves as the surface electrode and electrode wire, and an insulating layer is coated on the surface of the electrode wire. It is connected to the electrode connecting wire with a snap-fit ​​positioning connection, and then the electrode connecting wire is connected to the back-end monitoring equipment to form a loop to receive signals. This technology reduces the possibility of damaging the vocal cords to a certain extent, but because the conductive coating is at risk of falling off during contact with the throat and changing position, it will reduce the sensitivity of signal transmission and cause certain damage to the human body. 3. Adhesive laryngeal regurgitation patch electrodes consist of an adhesive layer and a membrane layer. The membrane layer has contact electrodes, connecting wires, and a connecting terminal. When in use, the adhesive layer is peeled off and the electrodes are attached to the endotracheal tube body. No structural modification of the tube body is required. However, the connecting wires are exposed outside the tube body, which can cause vocal cord contusion and the risk of detachment, posing a high risk of injury to the body.

[0004] During thyroid surgery, poor glottic exposure or misalignment of the glottis with the endotracheal tube (ET) during intubation is a common problem. A narrow bend angle prevents the endotracheal tube from entering the glottis, leading to intubation failure. A wide bend angle can easily cause the endotracheal tube to hit the dorsal epiglottis, preventing glottis entry or hindering tube advancement, resulting in soft tissue damage or intubation failure. Currently, visualization techniques can be used to enhance intubation visualization. However, if the glottis is too high, too low, or misaligned, the surgeon must constantly adjust the endotracheal tube's tip to achieve the correct position, which can cause a certain degree of bending and deformation. Current solutions involve clamping the endotracheal tube with a tube clamp or inflating the endotracheal tube cuff to tilt the tip of the endotracheal tube to facilitate glottic entry. Both methods require the operator and assistant to collaborate, are time-consuming, difficult to control, and can easily lead to soft tissue damage. Therefore, constant monitoring of the endotracheal tube's bend is essential.

[0005] Therefore, in order to solve the above problems, reduce the probability of recurrent laryngeal nerve injury during thyroid surgery and assist doctors in intubation smoothly, a multifunctional neuro-monitoring endotracheal intubation is needed. Summary of the Invention

[0006] The utility model aims to provide a neurological monitoring endotracheal cannula, which is used to solve the technical problems in the prior art of inaccurate recurrent laryngeal nerve collection results, high risk factor in the collection process and unpredictable bending degree of the endotracheal cannula.

[0007] The purpose of the present invention is also to provide a nerve monitoring system.

[0008] The technical solution of the utility model to solve the technical problem is:

[0009] A neurological monitoring endotracheal tube comprises an endotracheal tube body, an inflatable cuff, an inflatable cuff inflation tube, an indicator balloon, and an endotracheal tube connector. The inflatable cuff is provided with an electromyographic signal detection unit at a set distance away from the insertion port end. The electromyographic signal detection unit comprises a contact electrode, an internal signal transmission circuit of the contact electrode, and an external connection line of the contact electrode; the contact electrode is provided on the outer surface of the endotracheal tube body for contacting the vocal cords; the signal output end of the contact electrode is connected to one end of the internal signal transmission circuit of the contact electrode; the other end of the internal signal transmission circuit of the contact electrode is connected to one end of the external connection line of the contact electrode; the connection line The other end of the contact electrode external connection line is used to connect to the monitor; a curvature sensor is arranged inside the tracheal tube body between the inflatable cuff and the electromyographic signal detection unit, the curvature sensor is connected to one end of the curvature sensor internal transmission line, the other end of the curvature sensor internal transmission line is connected to one end of the curvature sensor connection line, and the other end of the curvature sensor connection line is used to connect to the monitor; the contact electrode internal signal transmission line and the curvature sensor internal transmission line are arranged on the outer surface of the tracheal tube body and are provided with an insulating layer; the contact electrode external connection line and the curvature sensor connection line are arranged outside the tracheal tube body.

[0010] Preferably, the contact electrodes include: a first contact electrode, a second contact electrode, a third contact electrode, and a fourth contact electrode; the signal transmission lines inside the contact electrodes include: a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line; that is, the first contact electrode is connected to the first transmission line, the second contact electrode is connected to the second transmission line, the third contact electrode is connected to the third transmission line, and the fourth contact electrode is connected to the fourth transmission line.

[0011] Preferably, the signal transmission circuit inside the contact electrode is a printed circuit.

[0012] Preferably, the connection between the internal signal transmission line of the contact electrode and the external connection line of the contact electrode is a snap-fit ​​positioning connection.

[0013] Preferably, the set distance is 3 cm to 5 cm away from the inflatable cuff to the insertion port.

[0014] Preferably, the curvature sensor is arranged 1.5 cm away from the insertion port end of the inflation cuff.

[0015] Preferably, the curvature sensor has a sandwich structure, and the structure from top to bottom is: an upper packaging layer, an upper sensitive gate, an intermediate base layer, a lower sensitive gate, and a lower packaging layer; it also includes: a first upper sensitive gate transmission line, a second upper sensitive gate transmission line, a first lower sensitive gate transmission line, and a second lower sensitive gate transmission line; the first upper sensitive gate transmission line, the second upper sensitive gate transmission line, the first lower sensitive gate transmission line, and the second lower sensitive gate transmission line are connected to the curvature sensor connecting line by welding.

[0016] Preferably, the electromyographic signal detection unit further includes a stimulation electrode, wherein the positive electrode and the negative electrode of the stimulation electrode are used to contact the vagus nerve or the recurrent laryngeal nerve.

[0017] A neurological monitoring system comprises a neurological monitoring tracheal cannula and a monitor.

[0018] The monitor includes: a power supply module, an amplifier, a filter, an analog-to-digital converter, a sensor driver, and a signal display and alarm system; the amplifier input end is respectively connected to the contact electrode external connection line and the curvature sensor connection line; the amplifier output end is connected to the filter input end; the filter output end is connected to the analog-to-digital converter input end; the analog-to-digital converter output end is connected to the sensor driver input end; and the sensor driver output end is connected to the signal display and alarm system.

[0019] The beneficial effects of the present invention are as follows: an electromyographic signal detection unit is arranged at a set distance away from the insertion port end of the inflatable cuff, and a contact electrode in the electromyographic signal detection unit is arranged on the outer surface of the endotracheal tube body to contact the vocal cords; the contact electrode is used to indirectly transmit nerve stimulation signals to achieve real-time monitoring of the recurrent laryngeal nerve during thyroid surgery, and human body damage is avoided while the monitoring results are highly accurate; a curvature sensor is arranged inside the endotracheal tube body between the inflatable cuff and the electromyographic signal detection unit, so that the degree of bending of the endotracheal tube can be measured, and the bending strain signal during the bending process of the front end of the endotracheal tube is read out by the rear-end instrument to monitor the degree of bending of the endotracheal tube in real time, assist the doctor in placing the tube, and further avoid soft tissue damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of the endotracheal cannula of the utility model;

[0021] Figure 2 It is a schematic diagram of the connection between the contact electrode, the internal transmission line of the contact electrode and the external connection line of the contact electrode in the myoelectric detection unit of the present invention;

[0022] Figure 3 This is a cross-sectional view of the endotracheal tube at the contact electrode in the present invention;

[0023] Figure 4 This is a cross-sectional view of the endotracheal tube at the transmission line inside the contact electrode of the present invention;

[0024] Figure 5 It is an enlarged schematic diagram of the connection between the contact electrode and the transmission line inside the contact electrode in the present invention;

[0025] Figure 6 This is a schematic diagram of the specific structure of the curvature sensor in the utility model;

[0026] Figure 7 It is a schematic diagram of the monitoring principle of the endotracheal intubation of the present utility model.

[0027] Description of the drawings: endotracheal tube body 1, inflatable cuff 2, inflatable cuff inflation tube 3, indicator balloon 31, curvature sensor connecting wire 4, contact electrode external connecting wire 5, endotracheal tube connector 6, electromyographic signal detection unit 7, first contact electrode 71, second contact electrode 72, third contact electrode 73, fourth contact electrode 74, curvature sensor 8, upper packaging layer 81, upper sensitive grid 801, middle base layer 83, lower sensitive grid 802, lower packaging layer 82, first upper sensitive grid Transmission line 803, second upper sensitive grid transmission line 804, first lower sensitive grid transmission line 805, second lower sensitive grid transmission line 806; monitor 9, contact electrode internal transmission line 10, curvature sensor internal transmission line 11, insulation layer 12, power supply module 14, amplifier 15, filter 16, analog-to-digital converter 17, sensor driver 18, signal display and alarm system 19, stimulation electrode 20, stimulation electrode positive electrode 201, stimulation electrode negative electrode 202. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0029] like Figure 1As shown, the utility model discloses a neurological monitoring endotracheal tube, comprising an endotracheal tube body 1, an inflatable cuff 2, an inflatable cuff inflation tube 3, an indicator balloon 31, and an endotracheal tube connector 6. The tip of the endotracheal tube body 1 is an insertion port; the inflatable cuff 2 is provided on the insertion port; the inflatable cuff inflation tube 3 is passed through the inner cavity of the endotracheal tube, one end of the inflatable cuff inflation tube 3 is located outside the endotracheal tube and communicates with the indicator balloon 31 with a one-way valve, and the other end passes through the inner cavity of the endotracheal tube and communicates with the inflatable cuff 2. An electromyographic signal detection unit 7 is provided at a set distance from the inflatable cuff 2 to the insertion port end. Preferably, the set distance is 3 cm to 5 cm away from the inflatable cuff to the insertion port end. A curvature sensor 8 is provided inside the endotracheal tube body between the inflatable cuff 2 and the electromyographic signal detection unit 7. Preferably, the curvature sensor 8 is provided 1.5 cm away from the insertion port end of the inflatable cuff.

[0030] like Figure 2 As shown, the electromyographic signal detection unit 7 includes a contact electrode, a signal transmission line 10 inside the contact electrode, and an external connection line 5 of the contact electrode. Figure 2 The connection mode of the contact electrode, the internal signal transmission line 10 of the contact electrode and the external connection line 5 of the contact electrode in the electromyographic signal detection unit is shown. The specific structure in the actual production process is only shown in FIG. Figure 2 For reference. Figure 3 As shown, the contact electrodes include: a first contact electrode 71, a second contact electrode 72, a third contact electrode 73, and a fourth contact electrode 74. Figure 3 A cross-sectional view of the endotracheal tube at the contact electrode is shown. The contact electrode is arranged on the outer surface of the endotracheal tube body 1 for contacting the vocal cords. The contact electrode is used to indirectly transmit nerve stimulation signals to achieve real-time monitoring of the recurrent laryngeal nerve during thyroid surgery to avoid damage. Generally, the main component of the contact electrode is conductive silver paste (or other conductive substances), and the shape is wavy. It can be attached to the endotracheal tube body by coating, spraying or printing. The thickness is 20μm, the length is 3cm, and the width is 0.2-0.4cm. The signal output end of the contact electrode is connected to one end of the internal signal transmission circuit 10 of the contact electrode; the internal signal transmission circuit 10 of the contact electrode is a printed circuit, such as Figure 4 As shown, the contact electrode internal signal transmission line 10 includes: a first transmission line 101, a second transmission line 102, a third transmission line 103, and a fourth transmission line 104; Figure 4 The cross-section of the endotracheal tube at the contact electrode internal signal transmission line is shown. The contact electrode internal signal transmission line is arranged on the outer surface of the endotracheal tube body and is provided with an insulating layer 12; the outside is covered with an insulating rubber layer to prevent external signal interference. Compared with the built-in wire circuit, the development of a porous cavity mold is avoided. Figure 5As shown, the first contact electrode 71 is connected to the first transmission line 101, the second contact electrode 72 is connected to the second transmission line 102, the third contact electrode 73 is connected to the third transmission line 103, and the fourth contact electrode 74 is connected to the fourth transmission line 104. The internal signal transmission line of the contact electrode is provided on the outer surface of the endotracheal tube and is provided with an insulating layer; the other end of the internal signal transmission line 10 of the contact electrode is connected to one end of the external connection line 5 of the contact electrode by a snap-fit ​​method; the external connection line of the contact electrode is provided outside the endotracheal tube, and the other end of the external connection line 5 of the contact electrode is connected to the monitor.

[0031] like Figure 1 As shown, the curvature sensor 8 is connected to one end of the curvature sensor internal transmission line 11, the other end of the curvature sensor internal transmission line 11 is connected to one end of the curvature sensor connection line 4, the other end of the curvature sensor connection line 4 is connected to the monitor, and the curvature sensor connection line is arranged outside the endotracheal tube body. The curvature sensor internal transmission line is arranged on the outer surface of the endotracheal tube body and is provided with an insulating layer 12; it is used to monitor the degree of bending deformation of the endotracheal tube. The curvature sensor 8 is a sandwich structure, such as Figure 6 As shown, the structure from top to bottom is: upper packaging layer 81, upper sensitive gate 801, middle base layer 83, lower sensitive gate 802, lower packaging layer 82; and also includes: first upper sensitive gate transmission line 803, second upper sensitive gate transmission line 804, first lower sensitive gate transmission line 805, and second lower sensitive gate transmission line 806.

[0032] Among them, the upper packaging layer 81 and the lower packaging layer 82 are used to protect the sensitive gate, and the material can be polyimide, polydimethylsiloxane (PDMS), etc.; the upper sensitive gate 801 and the lower sensitive gate 802 are the main sensing materials, and the sensitive gate pattern can be directly obtained using conductive copper foil or a photolithography machine. After degumming, a layer of metal platinum or carbon material is coated on the pattern as a conductive material by sputtering. The sensitive gates are located on both sides of the middle base layer, and their relative sizes and positions completely overlap. At their endpoints, they are soldered to the first upper sensitive gate transmission line 803, the second upper sensitive gate transmission line 804, the first lower sensitive gate transmission line 805, and the second lower sensitive gate transmission line 806; the material of the middle base layer 83 is one of polyimide (PI) or PP, which makes it easier to capture bending signals during the monitoring process and has higher sensitivity. The first upper sensitive gate transmission line 803, the second upper sensitive gate transmission line 804, the first lower sensitive gate transmission line 805, and the second lower sensitive gate transmission line 806 are connected to the curvature sensor connection line 4 by welding. Specifically, the length and width of the upper and lower packaging layers 81 and 82 can be set to 2 cm, the length of the upper and lower sensitive gates 801 and 802 can be set to between 0.5 and 1.5 cm, the total width can be set to 0.5 cm, and the thickness can be set to between 0.3 and 0.5 mm. The first upper sensitive gate transmission line 803, the second upper sensitive gate transmission line 804, the first lower sensitive gate transmission line 805, and the second lower sensitive gate transmission line 806 can all pass through one or both sides of the upper and lower sensitive gates 801 and 802.

[0033] like Figure 7As shown, a neurological monitoring system includes a neurological monitoring endotracheal tube and a monitor. The monitor includes: a power supply module 14, an amplifier 15, a filter 16, an analog-to-digital converter 17, a sensor driver 18, and a signal display and alarm system 19. The input end of the amplifier 15 is respectively connected to the contact electrode external connection line 5 and the curvature sensor connection line 4; the output end of the amplifier 15 is connected to the input end of the filter 16; the output end of the filter 16 is connected to the input end of the analog-to-digital converter 17; the output end of the analog-to-digital converter 17 is connected to the input end of the sensor driver 18; and the output end of the sensor driver 18 is connected to the signal display and alarm system 19. The monitor processes the signals transmitted by the stimulation electrode 20 and the curvature sensor 8 in the electromyographic signal detection unit 7 through functional circuits such as amplification and filtering. Specifically, the stimulation signal provided by the stimulation electrode is as follows: the positive electrode 201 and the negative electrode 202 of the stimulation electrode contact the vagus nerve or the recurrent laryngeal nerve, inducing nerve impulses to control the movement of the laryngeal muscles and vocal cords and generating action potentials. The analog-to-digital converter 17 converts the electromyographic voltage signal and the curvature voltage signal conditioned at the front end into digital signals that can be used by the chip. The sensor driver 18 calibrates and conditions the collected electromyographic signal and curvature signal through the standard data of the sensor, and then transmits the digital signal to the signal display and alarm system 19, which displays the bending angle of the tracheal tube in real time to remind the doctor to adjust the position of the tracheal tube in time; the electromyographic wave and the audio alarm sound are used to assist the doctor in determining whether the recurrent laryngeal nerve is damaged.

[0034] The electromyographic signal measurement process is as follows: a stimulation signal is applied to the vagus nerve through the positive electrode 201 and the negative electrode 202 of the stimulation electrode. The stimulation signal is an alternating current signal. The alternating current signal is 1-3 mA and the current frequency is 4 Hz. The stimulation electrode induces nerve impulses to control the laryngeal muscles and vocal cord movement and generates an action potential. Then, the contact electrode on the tracheal tube that contacts the vocal cords receives the action potential and transmits the electrical signal to the monitor 9 through the internal signal transmission line 10 of the contact electrode and the external connection line 5 of the contact electrode. The monitor 9 receives the electrical signal and amplifies, filters, and performs analog-to-digital conversion on the electrical signal monitored by the contact electrode in sequence through the amplifier 15, filter 16, analog-to-digital converter 17, and sensor driver 18, and displays and alarms in the form of electromyographic waves and audio through the signal display and alarm module 19.

[0035] The curvature signal measurement process is as follows: during the operation, as the endotracheal tube is inserted, the curvature sensor 8 causes the middle base layer 83 to bend, thereby driving the sensitive grids on both sides to produce tensile and compressive deformation. After bending, the concave side (lower sensitive grid 802) is compressed to produce compressive strain, and the convex side (upper sensitive grid 801) is stretched to produce tensile strain. The curvature sensor 8 transmits the curvature signal of the monitored endotracheal tube through the curvature sensor internal transmission line 11 and the curvature sensor connecting line 4 to the monitor 9. The monitor 9 receives the feedback signal and amplifies, filters, and performs analog-to-digital conversion on the electrical signal monitored by the curvature sensor 8 in sequence through the amplifier 15, filter 16, analog-to-digital converter 17, and sensor driver 18, and displays it in the form of a bending angle through the signal display and alarm module 19, reminding the doctor to adjust the curvature of the endotracheal tube in real time.

[0036] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

Claims

1. A neurological monitoring endotracheal tube, comprising an endotracheal tube body, an inflatable cuff, an inflatable cuff inflation tube, an indicator balloon, and an endotracheal tube connector, characterized in that: An electromyographic signal detection unit is provided at a set distance away from the insertion port end of the inflatable cuff, and the electromyographic signal detection unit includes a contact electrode, an internal signal transmission circuit of the contact electrode, and an external connecting wire of the contact electrode; the contact electrode is provided on the outer surface of the endotracheal tube body for contacting the vocal cords; the signal output end of the contact electrode is connected to one end of the internal signal transmission circuit of the contact electrode; the other end of the internal signal transmission circuit of the contact electrode is connected to one end of the external connecting wire of the contact electrode; the other end of the external connecting wire of the contact electrode is used to be connected to a monitor; a curvature sensor is provided inside the endotracheal tube body between the inflatable cuff and the electromyographic signal detection unit, the curvature sensor is connected to one end of the internal transmission circuit of the curvature sensor, the other end of the internal transmission circuit of the curvature sensor is connected to one end of the curvature sensor connecting wire, and the other end of the curvature sensor connecting wire is used to be connected to the monitor; the internal signal transmission circuit of the contact electrode and the internal transmission circuit of the curvature sensor are provided on the outer surface of the endotracheal tube body and are provided with an insulating layer; the external connecting wire of the contact electrode and the curvature sensor connecting wire are provided outside the endotracheal tube body.

2. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The electromyographic signal detection unit further includes a stimulation electrode, wherein the positive electrode and the negative electrode of the stimulation electrode are used to contact the vagus nerve or the recurrent laryngeal nerve.

3. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The contact electrodes include: a first contact electrode, a second contact electrode, a third contact electrode, and a fourth contact electrode; the internal signal transmission lines of the contact electrodes include: a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line; that is, the first contact electrode is connected to the first transmission line, the second contact electrode is connected to the second transmission line, the third contact electrode is connected to the third transmission line, and the fourth contact electrode is connected to the fourth transmission line.

4. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The signal transmission circuit inside the contact electrode is a printed circuit.

5. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The connection mode between the internal signal transmission line of the contact electrode and the external connection line of the contact electrode is a snap-fit ​​positioning connection.

6. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The set distance is 3 cm to 5 cm away from the inflatable cuff to the insertion port.

7. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The curvature sensor is arranged 1.5 cm away from the insertion port end of the inflation cuff.

8. The neurological monitoring endotracheal intubation according to claim 1, characterized in that: The curvature sensor has a sandwich structure, and the structure from top to bottom is: an upper packaging layer, an upper sensitive gate, an intermediate base layer, a lower sensitive gate, and a lower packaging layer; it also includes: a first upper sensitive gate transmission line, a second upper sensitive gate transmission line, a first lower sensitive gate transmission line, and a second lower sensitive gate transmission line; the first upper sensitive gate transmission line, the second upper sensitive gate transmission line, the first lower sensitive gate transmission line, and the second lower sensitive gate transmission line are connected to the curvature sensor connecting line by welding.

9. A neural monitoring system, characterized in that: include: The neurological monitoring endotracheal intubation and monitor according to any one of claims 1 to 8.

10. The nerve monitoring system according to claim 9, characterized in that: The monitor includes: a power supply module, an amplifier, a filter, an analog-to-digital converter, a sensor driver, and a signal display and alarm system; the amplifier input end is respectively connected to the contact electrode external connection line and the curvature sensor connection line; the amplifier output end is connected to the filter input end; the filter output end is connected to the analog-to-digital converter input end; the analog-to-digital converter output end is connected to the sensor driver input end; and the sensor driver output end is connected to the signal display and alarm system.

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