CN114947813A

CN114947813A - Weak magnetic detection method and endoscope detector

Info

Publication number: CN114947813A
Application number: CN202210749814.XA
Authority: CN
Inventors: 杨戴天杙; 明繁华
Original assignee: Ankon Technologies Co Ltd
Current assignee: Ankon Technologies Co Ltd
Priority date: 2022-06-28
Filing date: 2022-06-28
Publication date: 2022-08-30
Also published as: WO2024002083A1

Abstract

The invention discloses a weak magnetic detection method and an endoscope detection device, wherein the weak magnetic detection method is used for detecting weak magnetic medical equipment in a non-magnetic cavity and comprises the following steps: acquiring a magnetic field observation vector formed by at least one observation point after the magnetic field changes on the reference sphere model; wherein the reference sphere model represents a geomagnetic field condition and has a first geomagnetic radius; and if the mode of the magnetic field observation vector and the first geomagnetic radius meet a preset number relation, judging that a weak magnetic source exists in the non-magnetic cavity, and outputting a presence signal. According to the weak magnetic detection method provided by the invention, only a weak magnetic field needs to be received, so that high-intensity radiation cannot be generated to damage a non-magnetic cavity, and meanwhile, due to the implementation of a fitting sphere model and simple vector judgment, the technical effects of high detection speed, simple process and low false triggering probability can be achieved.

Description

Weak magnetic detection method and endoscope detector

Technical Field

The invention relates to the technical field of medical treatment, in particular to a weak magnetic detection method and an endoscope detector.

Background

At present, the endoscope discharge detection method provided in the medical technical field mainly focuses on outputting an acoustic signal or an optical signal when the endoscope is discharged from the body by itself so as to remind a patient to recover the endoscope by himself, but the experience feeling brought by the scheme is poor, and the phenomenon that the endoscope is triggered by mistake in the body of the patient or the phenomenon that the endoscope cannot trigger an alarm through a photosensitive element due to the shielding of excrement after being discharged from the body cannot be avoided. The prior art also provides a technical scheme for detecting the internal condition of the digestive tract of a patient through X-ray and further judging whether an endoscope still exists in the body of the patient, and although the position of the endoscope can be accurately detected, the X-ray shooting process is complex, the time consumption is long, and the endoscope has damage to the human body. Therefore, how to provide a weak magnetic detection method which has low false triggering probability, no damage to human body, and convenient and rapid detection process, and can be applied to the medical technical field, becomes a technical problem to be solved urgently.

Disclosure of Invention

The invention aims to provide a weak magnetic detection method to solve the technical problems of poor detection effect and low detection speed on weak magnetic medical equipment, harm to a human body in the detection process and high false triggering probability in the prior art.

It is an object of the present invention to provide an endoscopic probe.

In order to achieve one of the above objects, an embodiment of the present invention provides a weak magnetic detection method for detecting weak magnetic medical equipment in a non-magnetic cavity, including: acquiring a magnetic field observation vector formed by at least one observation point on the reference sphere model after the magnetic field changes; wherein the reference sphere model represents a geomagnetic field condition and has a first geomagnetic radius; and if the mode of the magnetic field observation vector and the first geomagnetic radius meet a preset number relation, judging that a weak magnetic source exists in the non-magnetic cavity, and outputting a presence signal.

As a further improvement of an embodiment of the present invention, the method specifically includes: if the modulus of the magnetic field observation vector is smaller than a first criterion value or the modulus of the magnetic field observation vector is larger than a second criterion value, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal; wherein the first criterion value is equal to a difference between the first geomagnetic radius and a first tolerance, and the second criterion value is equal to a sum of the first geomagnetic radius and a first tolerance, the first tolerance characterizing a difference between modes of different magnetic field vectors in the reference sphere model.

As a further improvement of an embodiment of the present invention, the method further comprises: receiving the presence signals, and acquiring the number and/or average duration of the presence signals; and if the number and/or the average duration of the existing signals are/is greater than a preset value, outputting an alarm signal.

As a further improvement of an embodiment of the present invention, the method further comprises: receiving the existence signal, and acquiring the modes of a plurality of magnetic field observation vectors within a preset time range; calculating the standard deviation of the modes of a plurality of magnetic field observation vectors to obtain a magnetic observation standard deviation; and when the magnetic observation standard deviation is less than or equal to a preset dynamic magnetic field threshold value, outputting an alarm signal.

As a further improvement of an embodiment of the present invention, the method specifically includes: acquiring a magnetic field observation vector formed by at least one observation point after the magnetic field changes on a reference sphere model and acceleration and rotation angular velocity change signals in the magnetic field change process to obtain mode, acceleration data and gyro data of the magnetic field observation vector; the method further comprises the following steps: receiving the existence signal, and calculating the standard deviation of the acceleration data and/or the average value of the gyro data to obtain the speed standard deviation and/or the gyro average value; and if the speed standard deviation is less than or equal to a preset dynamic speed threshold value and/or when the gyro mean value is less than or equal to a preset dynamic rotation threshold value, outputting an alarm signal.

As a further improvement of an embodiment of the present invention, the method specifically includes: acquiring multi-azimuth geomagnetic field data, and fitting in a three-dimensional coordinate system to obtain the reference sphere model; calculating to obtain a multi-azimuth geomagnetic field vector according to the geomagnetic field data; calculating to obtain a first tolerance in the preset quantity relation according to the modulus of the geomagnetic field vector; wherein the first tolerance characterizes a difference between modes of different magnetic field vectors in the reference sphere model, the geomagnetic field vectors being configured as directed line segments pointing from a center of sphere of the reference sphere model to a location of the geomagnetic field data in the three-dimensional coordinate system; the first tolerance is configured as an integer multiple of a standard deviation of a modulus of the earth-magnetic field vector.

As a further improvement of an embodiment of the present invention, the method further comprises: acquiring geomagnetic field data of a plurality of magnetic sensors in multiple directions, and fitting a plurality of sphere models in a three-dimensional coordinate system to obtain a plurality of calibration sphere models; calculating the center of the calibration sphere model and the vector from the center of the reference sphere model to the calibration point to obtain a plurality of calibration centers and calibration vectors; calibrating a plurality of calibration vector models by using a calibration vector of one of the plurality of calibration sphere models to obtain a plurality of data vectors; calculating to obtain a plurality of data points according to the data vectors and the corresponding calibration sphere centers, and fitting a reference sphere model in a three-dimensional coordinate system according to the data points; distributing the magnetic field data on the calibration sphere model to form a plurality of calibration points; the calibration vector is a calibration vector of one of the calibration sphere models in a preset direction; the method specifically comprises the following steps: obtaining a vector corresponding to the observation point in a first state to obtain a first observation vector; acquiring a vector corresponding to the observation point in a second state, and calibrating by using the calibration vector to obtain a second observation vector; and if the modulus of the second observation vector and the first geomagnetic radius meet a preset quantity relationship, judging that the weak magnetic source exists in the nonmagnetic cavity, and outputting the existence signal.

As a further improvement of an embodiment of the present invention, the calibration sphere model is an ellipsoid, and the preset direction is a long axis direction of the ellipsoid, and the method specifically includes: calculating to obtain a plurality of calibration parameters according to the calibration vectors and the models of the plurality of calibration vectors; wherein the calibration parameter is a quotient of a modulus of the calibration vector and a modulus of the calibration vector; respectively calibrating the modes of the calibration vectors according to the calibration parameters to obtain a plurality of data vectors; the method specifically comprises the following steps: acquiring calibration parameters corresponding to the first observation vector to obtain observation calibration parameters; and acquiring a vector corresponding to the observation point in the second state, and calibrating by using the observation calibration parameters to obtain a second observation vector.

As a further improvement of an embodiment of the present invention, the method further comprises: if the mode of the magnetic field observation vector does not meet the preset quantitative relation with the first geomagnetic radius, tracking the condition that the distance between at least two observation points on the reference sphere model changes along with the magnetic field to obtain a distance change value; and if the distance change value and a preset distance change threshold value meet a preset quantity relationship, judging that a weak magnetic source exists in the non-magnetic cavity.

As a further improvement of an embodiment of the present invention, the method further comprises: tracking the dispersion conditions of at least two groups of observation point sets on the reference sphere model to obtain first dispersion data and second dispersion data, and tracking the integral dispersion conditions of the at least two groups of observation points to obtain global dispersion data which are respectively used for representing the condition that the distance between the observation points changes along with the magnetic field; and if the global dispersion data and the preset interval change threshold value, the first dispersion data and the second dispersion data meet the preset quantity relationship, judging that a weak magnetic source exists in the non-magnetic cavity.

In order to achieve one of the above objects, an embodiment of the present invention provides an endoscope probe for probing an endoscope in a human body, the endoscope being configured to have weak magnetism, the endoscope probe comprising a probing panel and a handle connected to the probing panel, the probing panel comprising a display surface and a sensing surface which are oppositely disposed, the endoscope probe being configured to implement the weak magnetism probing method according to claims 1 to 8.

As a further improvement of an embodiment of the present invention, the display surface is provided with an alarm lamp and a status lamp which are configured in a ring shape, the sensing surface is uniformly distributed with at least four sensing units, the sensing units comprise at least two magnetic sensors, one of the magnetic sensors is arranged on one side close to a geometric center of the sensing surface, and the other of the magnetic sensors is arranged on one side far from the geometric center.

Compared with the prior art, the invention utilizes weak magnetism carried by medical equipment to detect the medical equipment in the nonmagnetic cavity, and tracks the vector change condition of a certain data point in the reference sphere model in different states by fitting the reference sphere model representing the intensity of the geomagnetic field, thereby carrying out comparison and judgment according to a certain preset quantity relation.

Drawings

FIG. 1 is a schematic view of a first side of an endoscopic detection device in accordance with an embodiment of the present invention;

FIG. 2 is a schematic view of a second side of an endoscopic probe in accordance with an embodiment of the present invention;

FIG. 3 is a schematic view of a third side of an endoscopic detection apparatus in accordance with another embodiment of the present invention;

FIG. 4 is a schematic view of a fourth side of an endoscopic detection device in accordance with another embodiment of the present invention;

FIG. 5 is a schematic view of the arrangement of the endoscopic probe device in cooperation with a human body in accordance with an embodiment of the present invention;

FIG. 6 is a schematic diagram of the scanning trajectory of the endoscopic detection device in accordance with an embodiment of the present invention;

FIG. 7 is a schematic view of the scanning trajectory of an endoscopic detection device in accordance with another embodiment of the present invention;

FIG. 8 is a schematic diagram of the steps of a weak magnetic detection method according to an embodiment of the present invention;

FIG. 9 is a schematic view of a magnetic field distribution in a specific application scenario of the weak magnetic detection method according to an embodiment of the present invention;

FIG. 10 is a schematic diagram of the steps of a weak magnetic detection method according to another embodiment of the present invention;

FIG. 11 is a schematic step diagram of a weak magnetic detection method according to a first embodiment of the present invention;

FIG. 12 is a schematic diagram illustrating signal changes of a first example of a weak magnetic detection method according to an embodiment of the present invention;

FIG. 13 is a schematic diagram illustrating the steps of a second embodiment of a weak magnetic detection method according to an embodiment of the present invention;

FIG. 14 is a schematic step diagram of a weak magnetic detection method according to a third embodiment of the present invention;

FIG. 15 is a schematic illustration of the steps of a weak magnetic detection method according to yet another embodiment of the present invention;

FIG. 16 is a schematic diagram illustrating steps of a specific example of a weak magnetic detection method according to still another embodiment of the present invention;

FIG. 17 is a schematic distribution diagram of a sphere model in a specific application scenario of the weak magnetic detection method according to still another embodiment of the present invention;

FIG. 18 is a schematic distribution diagram of a sphere model in another specific application scenario of the weak magnetic detection method according to still another embodiment of the present invention;

FIG. 19 is a schematic distribution diagram of a reference sphere model in a specific application scenario of the weak magnetic detection method according to still another embodiment of the present invention;

FIG. 20 is a schematic step diagram showing a first example of a specific example of a weak magnetic detection method according to still another embodiment of the present invention;

FIG. 21 is a schematic step diagram showing a second example of a specific example of a weak magnetic detection method according to still another embodiment of the present invention;

FIG. 22 is a schematic view of a magnetic field distribution in a specific application scenario of a weak magnetic detection method according to another embodiment of the present invention;

fig. 23 is a distribution diagram of a change process of observation points in a specific application scenario of the weak magnetic detection method according to another embodiment of the present invention;

fig. 24 is schematic diagrams of two possible distributions of observation points after change in a specific application scenario of the weak magnetic detection method according to another embodiment of the present invention.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.

It should be noted that the term "comprises/comprising" or any other variation thereof is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," "seventh," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The weak magnetic detection tool is often configured to carry a weak magnetic detection method for detecting weak magnetic equipment in the nonmagnetic cavity, and due to the fact that the magnetism of the weak magnetic equipment is weak, the weak magnetic equipment is usually difficult to accurately measure after being superimposed with external geomagnetic fields and other interferences, an operator cannot accurately know whether the weak magnetic equipment and the current state condition of the weak magnetic equipment are still reserved in the nonmagnetic cavity.

In the medical field, the above problem is generally reflected in that it is difficult for medical workers to determine whether or not an endoscope that can be regarded as the weak magnetic device is still included in a human body that can be regarded as a non-magnetic cavity. If the endoscope (particularly, capsule endoscope) is not smoothly discharged from the human body, the endoscope is left for a long time, which makes the subsequent medical treatment difficult, and there is a high possibility of causing secondary damage to the human body.

In view of this, the present invention provides an endoscopic probe apparatus for probing an endoscope in a human body, the endoscope being configured to have weak magnetism. Of course, the endoscope detection device can be further applied to other technical fields under the condition of meeting similar precision requirements, so that any weak magnetic equipment existing in the nonmagnetic cavity can be detected.

In an embodiment of the present invention, the endoscopic detecting device 1 is structured as shown in fig. 1 and fig. 2, and includes a detecting panel 11, and a handle 12 pivotally connected to the detecting panel 11, the detecting panel 11 further includes a display surface 111 and a sensing surface 112 disposed opposite to each other, wherein the display surface 111 may be disposed on a first side surface of the endoscopic detecting device 1 (or the detecting panel 11), and the sensing surface 112 may be disposed on a second side surface of the endoscopic detecting device 1 (or the detecting panel 11). Preferably, the endoscopic detection device 1 is configured to implement a weak magnetic detection method to achieve an endoscopic detection function.

Further, the handle 12 may be configured in an elongated block shape and may be arranged in a first plane along a length extension direction thereof, the first plane may be configured to be perpendicular to a plane in which the detection panel 11 is located, and further, the handle 12 may preferably be configured to be rotated in the first plane about a pivotal connection portion thereof with the detection panel 11 to adjust a relative positional relationship of the handle 12 and the detection panel 11. In actual use, an operator holds the handle 12 and arranges the detection panel 11 close to the nonmagnetic cavity, and based on the above structural configuration, the operator can easily adjust the posture of the detection panel 11 by adjusting the relative positional relationship between the two. Of course, in other embodiments, the detecting panel 11 and the handle 12 may also be configured as a fixed connection with fixed relative positions, the handle 12 and the detecting panel 11 may extend along the same horizontal plane, or the handle 12 and the detecting panel 11 may be disposed at an angle, so as to facilitate the detecting panel 11 to be close to the non-magnetic cavity to be detected.

In the present embodiment, the handle 12 may further be provided with an indicator light 121 for indicating the power supply status and/or the fault status of the endoscopic detection apparatus 1, for example, in a case, the indicator light 121 is configured to emit a first color light in a charging status, a second color light in a using status, and/or a third color light in an insufficient power status; for another example, in another case, the indicator lamps 121 are configured to be at least two to show the current power supply state by how many the number of the indicator lamps 121 are lighted; for example, in another case, the indicator light 121 is configured to emit a strobe light or a continuous light to indicate when an operation abnormality of the internal components of the endoscopic detection apparatus 1 is detected.

The handle 12 may further include a receiving chamber 122, and the receiving chamber 122 may be configured as a battery chamber for receiving a power supply battery, and may also be configured as a control chamber for receiving components for implementing the weak magnetic detection function. In consideration of beauty and convenience in use, the indicator lamp 121 is disposed on one side of the handle 12 close to the detection panel 11, and the accommodating cavity 122 is disposed on one side of the handle 12 far away from the detection panel 11, so that after the operator holds the endoscope, the palm is enough to cover the accommodating cavity 122 to protect internal components, and the indicator lamp 121 is not easily shielded to facilitate checking the state of the current endoscope detection device 1. For the same reason, at least the indicator light 121 may be disposed on the same side (may be the first side) of the display surface 111.

Of course, the exposed cover plate of the receiving chamber 122 can be configured to be in the same plane with other parts of the handle 12 to improve the integrity of the handle 12. In view of the advantages of grip stability, it is of course possible to configure the cover plate to protrude from other parts of the handle 12 and form an ergonomic shape, so as to increase the friction force between the palm and the handle 12 and enhance the grip effect.

Preferably, the display surface 111 may further include a warning lamp 1111 and a status lamp 1112 configured in a ring shape, although the warning lamp 1111 and the status lamp 1112 may also be configured in an arc shape or other shapes, such as a semicircular arc where the warning lamp 1111 is configured to be located at a position on the display surface 111 away from or close to the handle 12, and a semicircular arc where the status lamp 1112 is configured to be located at a position on the display surface 111 close to or away from the handle 12.

Specifically, the warning lamp 1111 and the status lamp 1112 may be configured as an integrated lamp strip, and may be lit at a preset brightness as a whole or at different levels of brightness as a whole after the occurrence of a preset warning condition or the reception of a preset status indication signal. The warning lamp 1111 may also be configured to be partially arc-lighted at a preset brightness, or partially arc-lighted at different levels of brightness, particularly in an embodiment where a plurality of magnetic sensors are disposed on the sensing surface 112, a plurality of portions of the warning lamp 1111 may be directly or indirectly connected to the plurality of magnetic sensors, respectively, so that when data detected by one or more magnetic sensors corresponds to a preset warning condition, the portions of the warning lamp 1111 may be reflected to issue a warning indication. In one embodiment, the preset alarm condition may be that the magnetic sensor detects a weak magnetic device (which may be a capsule endoscope in a human body) or a weak magnetic signal in the non-magnetic cavity, and based on this, for example, when the weak magnetic device or the weak magnetic signal is located at the upper left of the detection panel 11, at least a part of the arc of the upper left corner of the alarm lamp 1111 may be lit, so as to display the detected weak magnetic condition, and instruct the operator to hold the endoscope detection apparatus 1 to move closer to the upper left, so as to further and quickly determine the location of the weak magnetic device, and perform the function of guiding the scanning path.

In addition, the status light 1112 may be used to indicate the current operating status of the endoscopic detection device 1, such as in a sensing state, a calibration state, or an initialization state. The above states can be distinguished by taking the description of the operation of the warning light 1111 into consideration, or by using different colored lights and flashing manners different from the above, for example, the state light 1112 is configured to be normally on when the endoscopic detection device 1 is in the sensing state, the state light 1112 is configured to be stroboscopic when the endoscopic detection device 1 is in the calibration state, and the state light 1112 is configured to have the effect of a "horse race light" when the endoscopic detection device 1 is in the initialization state.

Fig. 2 shows the second side of the endoscopic probe 1 in a configuration in which at least four sensing units 1120 are evenly distributed on the sensing surface 112. In the case where the handle 12 extends in the vertical direction as shown in fig. 2, the at least four sensing units 1120 may be arranged to intersect in the cross direction, the sensing units 1120 located at the left and right sides may be configured to extend in the horizontal direction, and the sensing units 1120 located at the upper and lower sides may be configured to extend in the vertical direction; of course, in the same case, the at least four sensing units 1120 may also be disposed crosswise along the "X" direction, and are mutually centrosymmetric and axisymmetric.

Further, the sensing units 1120 may respectively include at least two magnetic sensors, and one of the magnetic sensors is disposed on a side close to the geometric center of the sensing surface 112, and the other of the magnetic sensors is disposed on a side far from the geometric center. In the embodiment shown in fig. 2, the sensing unit 1120 may include a first magnetic sensor 1120A and a second magnetic sensor 1120B, the first magnetic sensor 1120A and the second magnetic sensor 1120B are disposed at intervals along a longitudinal extending direction of the sensing unit 1120, the first magnetic sensor 1120A is disposed at a side close to a geometric center of the sensing surface 112, and the second magnetic sensor 1120B is disposed at a side far from the geometric center of the sensing surface 112. The other magnetic sensors may have the same configuration as described above, and may have other magnetic sensor configurations.

It is understood that the sensing units 1120 on the sensing surface 112 may be configured as eight units, which are respectively disposed along the "cross" direction and the "X" direction, and the arrangement of the sensing units 1120 in the present invention is not limited to the specific examples provided above. Meanwhile, the two magnetic sensors arranged in the single sensing unit 1120 have the effect of improving the anti-interference capability of the endoscopic detection apparatus 1, and based on this, the number of the magnetic sensors in the single sensing unit 1120 can be increased or decreased according to the needs and the consideration of cost control.

In one embodiment of the endoscopic probe device 1 provided above, as shown in fig. 1 and 2, the probe panel 11 is configured to have a circular extension, thereby accommodating more sensing units 1120 in a smaller space and forming a more aesthetic appearance. Of course, as shown in fig. 3 and 4, in another embodiment, the detection panel 11 may also be configured to have an extension surface with a shape of a rectangle, a rounded rectangle, or the like, so that the endoscopic detection device 1 is configured to have a larger length component enough to extend into a narrower space, and the extended device is applicable to a scene and is more convenient to store.

In this other embodiment, as shown in fig. 3 and 4, the endoscopic detection device 1 may also include a detection panel 11 and a handle 12 connected to the detection panel 11, the detection panel 11 may also include a display surface 111 and a sensing surface 112 disposed opposite to each other, and the endoscopic detection device 1 may also be configured to implement a weak magnetic detection method to detect an endoscope with weak magnetism in a human body.

In an embodiment where the detection panel 11 is configured to have a rounded rectangular extension, the alarm lamp 1111 and the status lamp 1112 in the display surface 111 may also be configured to have a bar shape with the same rounded rectangle to maintain the consistency of the design language. As in the former embodiment, the warning lamp 1111 may be provided outside the status lamp 1112 and arranged along an edge of the detection panel 11. Meanwhile, in order to maintain the portability of the endoscopic probe device 1 as much as possible without losing the sensing accuracy thereof, the sensing element 1120 may be provided in plural, preferably 5, at intervals in the longitudinal extending direction of the probe panel 11 so as to achieve the detection effect at different positions in the longitudinal extending direction. Of course, in this configuration, the alarm lamp 1111 and the sensing element 1120 may be configured to have the above-mentioned connection relationship and function, so as to achieve the technical effect of the endoscope tracking navigation.

Since it is necessary to leave sufficient space for the sensing element 1120, resulting in a long configuration of the probe panel 11, in this embodiment, the length of the handle 12 can be shortened adaptively to keep the balance of the overall size of the endoscopic probe device 1. Meanwhile, the connection relationship between the handle 12 and the detection panel 11 may also be configured as a pure fixed connection, so as to facilitate the operator to hold the handle 12 and control the position and orientation of the detection panel 11. Likewise, the handle 12 may also be provided with an indicator light 121 and a housing chamber 122, with reference to the functional arrangement provided by the previous embodiment.

The rounded rectangular probe panel 11 shape configuration allows for greater coverage of the sensing surface 112, making the scanning process faster. Of course, the present invention is not limited to the above two configurations, and many other configurations with fixed shapes or configurations with variable shapes may be derived based on the above configuration; meanwhile, although the sensing elements 1120 are configured to be uniformly distributed on the sensing surface 112 with a fixed relative position relationship in the foregoing, the embodiment of configuring the sensing elements 1120 to be flexibly detachable and/or adjustable in relative position is not excluded, and those skilled in the art may replace the sensing elements 1120 as needed. Notably, in an optional aspect, the magnetic sensor may be configured as an AMR (Anisotropic magnetoresistive) sensor or a TMR (Tunneling magnetoresistive) sensor.

Fig. 5 shows a state of fitting the endoscopic probe 1 to the human body 2, and since the detection depth of the endoscopic probe 1 is greatly affected by the intensity of the magnetic source, when the magnet provided in the endoscope is detected and the magnetic sensor faces the north-south pole of the magnet, it can reach 20cm to 30cm, based on which the endoscopic probe 1 can be scanned in close proximity to the surface of the human abdomen 21 so that the detection range 100 of the endoscopic probe 1 is enough to cover the portion between the surface of the human abdomen 21 and the human spine 22.

In addition, although a ferromagnetic material such as metal may interfere with the detection process of the endoscopic detection device 1, the detection process can be performed normally when the surface of the abdomen 21 of the human body (for example, on clothes) is not provided with a significant ferromagnetic substance. Meanwhile, when the detection panel 11 of the endoscope detection device 1 is close to the surface of the human abdomen 21, an angle can be formed between the detection panel 11 and the handle 12, so that the detection panel is convenient for an operator to hold, and the detection panel 11 can be always kept close to the human abdomen 21 in the process of moving the endoscope detection device 1.

The endoscopic detection apparatuses 1 provided in the above two embodiments may have different scanning steps, respectively. As shown in fig. 6, which shows the scanning step of the endoscopic detection device 1 provided in the former embodiment, based on the above-mentioned structural configuration, the detection range 100 formed by the endoscopic detection device 1 can be the same circle, and when facing the rectangular-like region to be measured 200 on the human body, because it is relatively small and light, it can scan in a polygonal line trajectory, such as an S-shape or a "hex" shape. As shown in fig. 7, in the scanning step of the endoscopic detection device 1 provided in the latter embodiment, based on the above-mentioned structural configuration, the detection range 100 formed by the endoscopic detection device 1 is in the same strip shape, and when facing the region to be measured 200, it can perform linear scanning, for example, back and forth scanning along the diagonal of the region to be measured 200, by taking advantage of the larger coverage area. Of course, any of the above scanning modes can be performed by holding the handle 12 pivotally or fixedly connected to the detection panel 11.

As shown in fig. 8, an embodiment of the present invention provides a weak magnetic detection method, which can be used to detect weak magnetic medical devices in a non-magnetic cavity, such as the endoscope for detecting the inside of a human body. The weak magnetic detection method specifically comprises the following steps:

step 31, acquiring a magnetic field observation vector formed by at least one observation point on the reference sphere model after the magnetic field changes;

and step 32, if the mode of the magnetic field observation vector and the first geomagnetic radius meet a preset number relationship, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal.

The reference sphere model represents the geomagnetic field condition and has a first geomagnetic radius.

Fig. 9 shows (part of) a magnetic field distribution diagram formed after the weak magnetic detection method is carried out in a specific application scenario. Specifically, the magnetic field distribution is mainly constituted by the reference sphere model 4, and the reference sphere model 4 is shaped like a "spherical shell" (the area of the arc-shaped solid line and the two arc-shaped dashed lines in the figure) and is constituted by fitting end points of a plurality of magnetic field vectors whose starting points are the spherical centers 40 of the reference sphere model 4.

With the first observation point 41 on the reference sphere model as the observation point, there is a possibility that a relative position change with respect to the reference sphere model 4 may occur differently at different times (at any time before or after the previous time) or in different states (which may be a change in the posture of the probe device or magnetic sensor mounted thereon or a change in the operating state of the probe device mounted thereon). For example, in one case, the first viewpoint 41 is moved to the position of the second viewpoint 42 and out of the coverage of the reference sphere model 4; for example, in another case, the first viewpoint 41 is moved to the position of the third viewpoint 43 so as to be out of the coverage of the reference sphere model 4; for example, in still another case, the first viewpoint 41 is moved to the position where the fourth viewpoint 44 is located and the relative positional movement occurs within the coverage of the reference sphere model 4.

The first geomagnetic radius may be a distance length from the center of sphere 40 to an arc-shaped solid line, i.e., R shown in the figure, where the arc-shaped solid line is located between two arc-shaped dashed lines and has a more balanced distance length with respect to the center of sphere 40. Therefore, at the moment, whether the observation point has larger fluctuation amplitude or not can be judged by judging the quantity relation between the modulus of the magnetic field observation vector formed after the observation point passes through the magnetic field change and the first geomagnetic radius, so that the observation point is separated from the spherical shell formed by the two arc-shaped dotted lines.

For example, in the initial state, the first observation point 41 forms a first observation vector 410 with the center of sphere 40, when the first observation point 41 moves to the position of the second observation point 42 under the influence of the magnetic field change, the second observation vector 420 with the center of sphere 40, when the first observation point 41 moves to the position of the third observation point 43 under the influence of another magnetic field change, the third observation vector 430 with the center of sphere 40, and when the first observation point 41 moves to the position of the fourth observation point 44 under the influence of another magnetic field change, the fourth observation vector 440 with the center of sphere 40. Therefore, the magnitude relation between the modulus of the second observation vector 420 and the first geomagnetic radius R can be compared, and the movement of the observation point due to the change of the magnetic field can be further determined.

For example, in one embodiment, it may be determined that there is a weak magnetic source outside the observation point that causes the observation point to deviate from the reference sphere model 4 when the first observation point 41 is moved to the position where the second observation point 42 is located, or when the third observation point 43 is moved to the position where the fourth observation point 44 is located, that there is no weak magnetic source outside the observation point that causes the observation point to deviate from the reference sphere model 4 when the first observation point 41 is moved to the position where the fourth observation point 44 is located.

As shown in fig. 10, another embodiment of the present invention provides a weak magnetic detection method, which specifically defines the content of the preset quantitative relationship of the previous embodiment, and specifically includes:

step 31, acquiring a magnetic field observation vector formed by at least one observation point after the magnetic field changes on the reference sphere model;

and step 32', if the modulus of the magnetic field observation vector is smaller than the first criterion value or the modulus of the magnetic field observation vector is larger than the second criterion value, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a existence signal.

The reference sphere model represents the geomagnetic field condition and has a first geomagnetic radius. The first criterion value is equal to a difference between the first geomagnetic radius and a first tolerance, and the second criterion value is equal to a sum of the first geomagnetic radius and a first tolerance, the first tolerance characterizing a difference between modes of different magnetic field vectors in the reference sphere model.

The step 32' of refining may be applied in any of the above-mentioned solutions, in particular in any of the above-mentioned definitions of the predetermined quantitative relationship. On the basis of this, the magnetic field observation vector before the magnetic field change is defined as B' _s Defining a first geomagnetic radius R ═ B _e Defining a first tolerance r _T If the above determination process is: if | B' _s |<|B _e |-r _T Or | B' _s |>|B _e |+r _T And judging that a weak magnetic source exists in the nonmagnetic cavity and outputting a presence signal. In this way, the characteristic that the observation points are generally uniformly distributed in the sphere shell of the reference sphere model 4 is utilized, so that the above judgment step can sufficiently cover most of the cases of observation point selection, and the output result is more accurate.

Wherein, B _e The earth-magnetic field vector detected in the space not containing the weak magnetic source can be characterized, and is preferably a calibrated earth-magnetic field vector, and in some embodiments, the modulus of the earth-magnetic field vector, or the intensity of the earth-magnetic field, can be the result of the square sum of the orthogonal components in the three directions of the earth-magnetic field, i.e., the square sum is the square sum of the components in the three directions of the earth-magnetic field

The first tolerance r _T Which may be estimated by actual measurements, the noise level of different magnetic sensors may be based on inherent differences in their hardware construction, and thus different magnetic sensors may have different first tolerances r _T Whether or not the magnetic sensor is subjected to uniform correction of sensitivity and bias.

As shown in fig. 11, a first example of a weak magnetic detection method in an embodiment of the present invention is provided, which specifically includes:

step 32, if the mode of the magnetic field observation vector and the first geomagnetic radius meet a preset number relationship, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal;

step 331, receiving the presence signals, and obtaining the number and/or average duration of the presence signals;

and step 332, if the number and/or the average duration of the signals are larger than a preset value, outputting an alarm signal.

In embodiments where

steps

31 and 32 are configured to be performed continuously, the output of the presence signal is not sufficient to be directly sufficient evidence for determining the presence of a weak magnetic source within the non-magnetic cavity, under high accuracy requirements, and therefore in this first embodiment, at least one of the number of presence signals and the duration of the output of the presence signal is determined.

Further, the number of the presence signals is preferably defined as the number of the magnetic sensors outputting the presence signals, so that the presence of the weak magnetic source can be comprehensively judged by combining the outputs of the plurality of magnetic sensors, the robustness of the detection process is improved, and the probability of false triggering is reduced. Meanwhile, the duration is preferably defined as an average duration, and may be an arithmetic average of a plurality of durations output by a single magnetic sensor in different detection periods, or an arithmetic average or weighted average of a plurality of durations output by a plurality of magnetic sensors in the same detection period, so that accidental alarms caused by excessive motion or other interference can be avoided. Preferably, the preset value for the number of presence signals may be 2 and the preset value for the duration may be 0.5 s. Notably, the above steps can be adaptively configured by the joint determination and the window monitoring determination described above.

Fig. 12 shows the signal variation output by the sensing unit 1120 and the alarm lamp 1111, wherein the sensing unit 1120 may be used to output a high level present signal sig (e) and a low level non-present signal sig (n), and the alarm lamp 1111 or its front end component may be used to receive or output a high level alarm signal sig (w) and a low level non-alarm signal sig (r), respectively. Thus, in fig. 12, the dashed box represents the average duration (or the monitoring window for detecting the average duration), and when the presence signal sig (e) is always and only included in the monitoring window, it is determined that the weak magnetic source is present, and after the duration of the monitoring window is over, an alarm signal is output, and the alarm lamp 1111 is triggered to form an alarm indication.

Certainly, in order to increase the response speed, the sampling rate of the detection apparatus may also be adaptively increased, the time length of the monitoring window is shortened (that is, the preset value for the average duration is shortened), and a compromise and appropriate preset value is selected on the basis of stabilizing the filtering noise, which may be adaptively configured as required. Also, the presence signal does not necessarily trigger any indication effect, and in one embodiment the detecting means is arranged to form a pre-alarm in response to said presence signal to prompt the operator to perform a detailed scan at the current location, and may be similarly arranged to perform a normal alarm operation.

As shown in fig. 13, a second example of the weak magnetic detection method in an embodiment of the present invention is provided, which specifically includes:

step 341, receiving the existing signal, and acquiring the modes of a plurality of magnetic field observation vectors within a preset time range;

step 342, calculating the standard deviation of the modulus of the plurality of magnetic field observation vectors to obtain a magnetic observation standard deviation;

and 343, outputting an alarm signal when the standard deviation of the magnetic observation is less than or equal to the preset dynamic magnetic field threshold.

In this second embodiment, a dynamic determination is provided that can correspond to the foregoingThe standard deviation is obtained to judge whether the detection device is in rapid and strong motion, thereby eliminating false alarm and other interference caused by the magnetic field change. The modes of the magnetic field observation vectors may be modes of a plurality of magnetic field observation vectors formed by a single magnetic sensor in a preset time range. Defining data length as L _m Or a plurality of magnetic field observation vectors formed in a preset time range, the mode defining the magnetic field observation vector corresponds to the sensing axis of the magnetic sensor to be j, wherein the sensing axis j can be any one of an x axis, a y axis or a z axis, and then the standard deviation std of magnetic observation is obtained _mag At least can be configured to satisfy:

std _mag ＝std(mag(L _m ,j))；

here, mag () represents data detected by any one of the magnetic sensors, and std () represents a standard deviation of the data sequence calculated. Thus, when the standard deviation std is observed magnetically _mag Satisfies std _mag >std _mTh When the detection device is judged to be in a violent movement or a rapidly changing magnetic field, the weak magnetic source cannot be judged to exist according to the current result, and an operator can be instructed to close the detection device to protect the detection device; standard deviation std when magnetically observed _mag Satisfies std _mag ≤std _mTh When the current detection device works normally, an alarm signal can be output corresponding to the existence signal output in the previous step; wherein std is _mTh Is the dynamic magnetic field threshold.

As shown in fig. 14, a third example of the weak magnetic detection method in an embodiment of the present invention is provided, which specifically includes:

step 31', obtaining a magnetic field observation vector formed by at least one observation point after the magnetic field changes on the reference sphere model, and acceleration and rotation angular velocity change signals in the magnetic field change process to obtain mode and acceleration data and gyro data of the magnetic field observation vector;

step 351, receiving the existing signal, calculating the standard deviation of the acceleration data and/or the average value of the gyro data, and obtaining the speed standard deviation and/or the gyro average value;

and 352, outputting an alarm signal if the speed standard deviation is less than or equal to a preset dynamic speed threshold value and/or when the gyro mean value is less than or equal to a preset dynamic rotation threshold value.

In the third embodiment, another solution corresponding to the above dynamic determination is provided, in which at least one of the acceleration data and the gyro data (or specifically, the standard deviation of the acceleration data and the average value of the gyro data) is received and obtained to determine whether the detecting device is in rapid and strong motion, so as to eliminate the false alarm and other interference caused by the magnetic field change. In this case, the detection device or other devices equipped with the weak magnetic detection method according to this embodiment may further include an acceleration sensor and/or a gyroscope, and of course, the above-mentioned components may be provided in one detection device, or may be integrated into each sensing element and integrally arranged in plural.

Defining data length as L _m (or acceleration data formed in a preset time range), defining the sensing axis of the magnetic sensor corresponding to the acceleration data as j, wherein the sensing axis j can be any one of an x axis, a y axis or a z axis, and then the standard deviation std of the speed _acc At least can be configured to satisfy:

std _acc ＝std(acc(L _m ,j))；

where acc () represents the data detected by any one of the acceleration sensors and std () represents the standard deviation of the data sequence calculated. Thus, when the standard deviation std of the speed is reached _acc Satisfies std _acc >std _aTh When the detection device is in a violent movement or a rapidly changing magnetic field, the existence of a weak magnetic source cannot be judged according to the current result, and an operator can be instructed to close the detection device to protect the detection device; when standard deviation std of speed _acc Satisfies std _acc ≤std _aTh When the current detection device works normally, an alarm signal can be output corresponding to the existence signal output in the previous step; wherein std is _aTh Is a stand forThe dynamic speed threshold.

Correspondingly, the data length is defined as L _m (or gyroscope data formed in a preset time range), defining a sensing axis j of the gyroscope data corresponding to the magnetic sensor, wherein the sensing axis j can be any one of an x axis, a y axis or a z axis, and then, defining a gyroscope mean value A _gyr At least can be configured to satisfy:

A _gyr ＝mean(gyr(L _m ,j))；

where gyr () represents data detected by any of the gyroscopes and mean () represents the average value of the data sequence. Thus, when the gyro mean value A _gyr Satisfies A _gyr >A _gTh When the detection device is in a violent movement or a rapidly changing magnetic field, the existence of a weak magnetic source cannot be judged according to the current result, and an operator can be instructed to close the detection device to protect the detection device; mean value of gyro A _gyr Satisfies A _gyr ≤A _gTh When the current detection device works normally, an alarm signal can be output corresponding to the existence signal output in the previous step; wherein, A _gTh Is the dynamic rotation threshold.

The reason for respectively calculating the standard deviation and the average value is that acceleration also exists in the normal use process of the detection device, so the acceleration change condition can be known by calculating the standard deviation, and the angle change is usually not obvious or even 0 in the normal use process of the detection device, so the current change condition can be rapidly known by calculating the average value. Those skilled in the art can derive further embodiments in light of this teaching.

It should be noted that the above three embodiments, although providing different steps for determining whether to alarm or not, are not necessarily isolated from each other. In order to avoid redundant description, the combination of the above three embodiments is not described too much, but it can be understood that in other embodiments, the output of the alarm signal may be configured to be achieved when any two, three or more of the number requirement, the duration requirement, the standard deviation requirement, the acceleration requirement and the gyro data requirement are met, so that mechanisms such as joint judgment, window monitoring, dynamic judgment and the like are introduced, and the probability of false triggering is further reduced. In one implementation, the third embodiment may be executed first and then the first embodiment, the second embodiment may be executed first and then the first embodiment may be executed, or the second embodiment and then the first embodiment may be executed simultaneously and then the first embodiment may be executed in order. Thus, a judgment logic of 'data receiving-data correcting-dynamic judgment-data analyzing-joint judgment-window monitoring judgment' can be formed.

As shown in fig. 15, another embodiment of the present invention provides a weak magnetic detection method, in which a plurality of pre-steps are added before weak magnetic detection, and the method specifically includes:

301, acquiring multi-azimuth geomagnetic field data, and fitting in a three-dimensional coordinate system to obtain a reference sphere model;

step 302, calculating to obtain a multi-azimuth geomagnetic field vector according to the geomagnetic field data;

step 303, calculating to obtain a first tolerance according to a modulus of the earth magnetic field vector;

The reference sphere model represents the geomagnetic field condition and has a first geomagnetic radius. The first tolerance characterizes a difference between modes of different magnetic field vectors in the reference sphere model. The geomagnetic field vector may be configured as a directed line segment pointing from a center of sphere of the reference sphere model to a location of the geomagnetic field data in the three-dimensional coordinate system. And the first tolerance may be configured to be equal to an integer multiple of a standard deviation of a modulus of the earth-magnetic field vector.

The tracking of the observation point and the acquisition and judgment of the model of the magnetic field observation vector need to be based on a reference sphere model, the reference sphere model can be preset before detection, and usually should be formed by fitting geomagnetic field data completely under the environment without including a weak magnetic source, and naturally can be formed by fitting under the combined action of an external magnetic field and a geomagnetic field under other special working conditions, such as the working condition that the detection environment requires the external constant magnetic field.

The fitting of the reference sphere model relies on multi-directional geomagnetic field data, and since the geomagnetic field data is relative to the terrestrial coordinate system, such raw geomagnetic field data (or geomagnetic field vector, as described above) can be defined as B _e (which may have a value range of 50-60 μ T) and which needs to be converted into a representation in a three-dimensional coordinate system fitted to the detection device, such detected geomagnetic field data may be defined as B _s Based on this, the earth magnetic field data B is detected _s At least can be configured to satisfy:

B _s ＝R _es B _e ；

wherein R is _es Is a transformation matrix. Based on that the geomagnetic field is uniform and stable, the posture of the detection device can be adjusted, so that the projection of the geomagnetic field on each axis at each part of the detection device (or called at each magnetic sensor) is changed, and under a working condition, the geomagnetic field can rotate in an open environment without extra magnetic field interference to obtain multi-azimuth geomagnetic field data, and the geomagnetic field data is measured according to each time t:

B _s (t)＝[B _x (t),B _y (t),B _z (t)]，

and drawing the detected geomagnetic field data into a three-dimensional coordinate system to form a reference sphere model in a fitting manner. Of course, the fitting of the geomagnetic field data to the reference sphere model can also have various embodiments, and the present invention is not limited to the vector fitting according to the geomagnetic field data. In one case, the geomagnetic data may also be defined as the coordinates of the corresponding geomagnetic field vector, and the technical effect expected in step 301 can also be achieved.

The present embodiment further provides a technical solution for calculating the first tolerance of the reference sphere model according to the model of the geomagnetic field vector, which may be calculating the maximum and minimum of the models of the multi-azimuth geomagnetic field vectorThe difference value of (2) is used as the first tolerance, but it may also be calculated as the standard deviation of the modulus of all geomagnetic field vectors, and directly using the standard deviation as the first tolerance, or using the standard deviation as the first tolerance after performing multiple operation (increasing the tolerance and improving the fault-tolerant rate of the model). In one embodiment, the first tolerance is defined as r _T Then at least configured to satisfy:

r _Ti ＝n·std({|B _si |} _1,2,...,M )；

wherein std () is a standard deviation operation function, { | B _si |} _1,2,...,M For the modulus of the M geomagnetic field vectors measured by the ith magnetic sensor, n is an empirical multiple, and the value range of n can be 1-3.

Further, in another embodiment, step 303 may further specifically include: and analyzing the model of the geomagnetic field vector, screening outliers, and calculating to obtain a first tolerance of the reference sphere model according to the screened model of the geomagnetic field vector. Thus, the accuracy of model fitting is further improved.

As shown in fig. 16, a specific example of a weak magnetic detection method according to still another embodiment of the present invention is provided, which specifically includes:

step 3011, acquiring geomagnetic field data of a plurality of magnetic sensors in multiple directions, fitting a plurality of sphere models in a three-dimensional coordinate system, and obtaining a plurality of calibration sphere models;

step 3012, calculating the center of the calibration sphere model and the vectors from the center of the sphere to the calibration points to obtain a plurality of calibration vectors for calibrating the center of the sphere;

step 3013, calibrating a plurality of calibration vector models with a calibration vector of one of the plurality of calibration sphere models to obtain a plurality of data vectors;

step 3014, calculating to obtain a plurality of data points according to the data vectors and the corresponding calibration sphere centers, and fitting a reference sphere model in a three-dimensional coordinate system according to the data points;

and step 32, if the modulus of the magnetic field observation vector and the first geomagnetic radius meet a preset quantitative relation, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a existence signal.

Distributing the magnetic field data on the calibration sphere model to form a plurality of calibration points; the calibration vector is a calibration vector of one of the calibration sphere models in a preset direction.

Since practical magnetic sensors often have a certain inconsistency, in order to further improve the detection accuracy and the quality of the reference sphere model, the present specific example provides a refinement step for step 301. It should be noted that, although step 302 and step 303 are omitted in this embodiment, this does not mean that this embodiment cannot combine the above steps to form a new technical solution.

Defining the magnetic field value measured on the j axis by the ith sensor in the detection device as B _ij It may be configured to at least satisfy:

wherein,

is a unit vector in the positive direction of the j axis,

a projection value representing geomagnetism on a j-axis of the sensor; k _ij For the conversion coefficient of sensor i on the j axis, the ideal value is 1, i.e. the output equals the input; d _ij Is a Bias (Bias).

The magnetic sensor is influenced by circuit design, manufacturing process and temperature variation, and the conversion coefficient K _ij May deviate from 1 by an offset D _ij It may not be 0, so that the magnetic sensor outputs a magnetic field value having an error, and the output in the absence of an applied magnetic field is not 0. The ellipsoid model with the center of sphere not at the origin as shown in fig. 17 is formed by reflection on the three-dimensional coordinate system, and can be defined as the calibration sphere model 4'.

The intensity of the geomagnetic field data acquired by the same magnetic sensor in different postures is different (also is the reason for calibrating the shape of the sphere model 4' like an ellipsoid). Based on the method, the multi-azimuth geomagnetic field data can be acquired by changing the posture of the magnetic sensor, and after an ellipsoid model is formed by fitting, the calibration center of the current ellipsoid model is defined as delta B _i Then, there may be:

ΔB _i ＝[ΔB _ix ,ΔB _iy ,ΔB _iz ]；

therefore, the offset of the calibration center of the ellipsoid model relative to the origin at least along the x-axis, the y-axis and the z-axis can be calculated, and the offset is as follows:

thus, the offset D can be obtained _ij And can further calibrate the spherical center coordinate [ Delta B [ ] _ix ,ΔB _iy ,ΔB _iz ]The dimensions of the calibration sphere model 4' in the respective directions (for example, the major and minor axes of the ellipsoid) are determined. Continuously, different calibration vectors can be calculated according to the calibration center and the dimensions in each direction, one of the different calibration vectors is selected as a calibration vector, and calibration processing (which may be scaling up or projection processing for a mold) is performed on the other calibration vectors, so as to finally generate a reference sphere model of the quasi-orthosphere corresponding to the magnetic sensor. Therefore, the problem that a sphere model is not standard due to the error of the magnetic sensor can be solved, and whether a weak magnetic source exists or not can be judged conveniently by using the mode of a magnetic field observation vector.

The above describes the fitting and processing procedure of geomagnetic field data of a single sensor in multiple directions, and it can be seen that the above steps 3011 to 3014 of the present invention are not limited to the case of multiple magnetic sensors, but may be: acquiring geomagnetic field data of the magnetic sensor in multiple directions, and fitting a sphere model in a three-dimensional coordinate system to obtain a calibration sphere model; calculating the center of the calibration sphere model and the vector from the center of the sphere to the calibration point to obtain a calibration center of the sphere and a calibration vector; calibrating the modes of a plurality of calibration vectors by taking one of the calibration vectors of the calibration sphere model as a calibration vector to obtain a plurality of data vectors; and calculating to obtain a plurality of data points according to the data vectors and the calibration sphere center, and fitting a reference sphere model in a three-dimensional coordinate system according to the data points.

Since the major axis and the minor axis of the ellipsoid do not necessarily extend along the x-axis, the y-axis or the z-axis, the weak magnetic detection method may further include: and determining a long axis and/or a short axis of the calibration sphere model, taking a vector of at least one of the long axis or the short axis as a calibration vector, and calibrating the modes of other calibration vectors to obtain a plurality of data vectors.

The degree of deviation of different magnetic sensors may be different, which may cause the output results of the magnetic sensors to have differences (e.g., different vector components, different total intensities, etc.), and a plurality of calibration sphere models 4' as shown in fig. 18 may be fitted. Based on this, the calibration sphere models may be generated by fitting the geomagnetic field data corresponding to the magnetic sensors, respectively, to the first calibration sphere model 4A ', the second calibration sphere model 4B', the third calibration sphere model 4C ', the fourth calibration sphere model 4D', the fifth calibration sphere model 4E ', the sixth calibration sphere model 4F', and the seventh calibration sphere model 4G 'in the calibration sphere model 4'.

Defining a first calibration sphere model 4A' formed by fitting the geomagnetic data obtained by the first magnetic sensor, assuming that a vector extending in the positive direction along the x-axis is taken as a calibration vector, the norm of the calibration vector is r _1x The modulus of the calibration vector corresponding to the ith magnetic sensor on the j axis is r _ij . Further, the norm r of the calibration vector may be scaled _1x Modulo r from other calibration vectors _ij And executing scalar operation to realize the calibration of other calibration vectors and correspondingly form a calibrated data vector.

The above process converts a plurality of calibration spherical models, which are ellipsoid-shaped, at different positions into a plurality of spherical models, which are true-sphere-like, at different positions, and because the calibration process may also include an offset D _ij To unify the calibration centers of the calibrated different calibration spheres as the origin of the three-dimensional coordinate system (calibration vector minus the corresponding offset D) _ij Or called Δ B _ij ) Therefore, after the plurality of calibration sphere models in fig. 18 are subjected to traversal processing, the reference sphere model 4 shown in fig. 19 is finally formed by uniform fitting, and geomagnetic field data detected by different magnetic sensors are distributed on the reference sphere model, so that the geomagnetic field data are sufficiently adapted to the subsequent steps of the weak magnetic detection method provided in the foregoing, and the magnetic field change of the observation point is used as an index for judging whether weak magnetic exists.

The steps improve the consistency of the detection data of different magnetic sensors in the detection device and the consistency of the detection data of different shafts of the same magnetic sensor.

As shown in fig. 20, a first example of a specific example of a weak magnetic detection method according to still another embodiment of the present invention specifically includes:

step 3011, acquiring geomagnetic field data of a plurality of magnetic sensors in multiple directions, and fitting a plurality of sphere models in a three-dimensional coordinate system to obtain a plurality of calibration sphere models;

step 3012, calculating the center of the calibration sphere model and the vectors from the center of the sphere to the calibration points to obtain a plurality of calibration centers and calibration vectors;

step 311, obtaining a vector corresponding to the observation point in the first state to obtain a first observation vector;

step 312, obtaining a corresponding vector of the observation point in the second state, and calibrating with the calibration vector to obtain a second observation vector;

and step 32', if the mode of the second observation vector and the first geomagnetic radius meet a preset number relation, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal.

The first embodiment provides a step 31 of refining and a corresponding step 32 ″ matching the above steps, wherein the first observation vector may correspond to the first observation vector 410 in fig. 9, the second observation vector may correspond to the second observation vector 420, the third observation vector 430 and the fourth observation vector 440 in fig. 9, or any other observation vector with changed state relative to the first observation vector 410.

In the present embodiment, step 301 and step 31 are configured in a refined manner in synchronization, but there is only a relationship between the two that step 31 depends on the calibration parameter generated in step 301. It is understood that step 301 can be implemented independently of step 31 to generate a more accurate reference sphere model, and the corresponding technical effects of the specific implementation provided in step 31 can be implemented in the alternative of the foregoing embodiments.

As shown in fig. 21, a second example of a specific example of a weak magnetic detection method according to still another embodiment of the present invention specifically includes:

30131, calculating a plurality of calibration parameters according to the calibration vectors and the models of the plurality of calibration vectors;

step 30132, calibrating the models of the plurality of calibration vectors according to the plurality of calibration parameters, respectively, to obtain a plurality of data vectors;

3121, acquiring calibration parameters corresponding to the first observation vector to obtain observation calibration parameters;

3122, obtaining a vector corresponding to the observation point in the second state to observe calibration parameter calibration, and obtaining a second observation vector;

and step 32', if the mode of the second magnetic field observation vector and the first geomagnetic radius meet a preset number relation, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal.

Wherein the calibration parameter is a quotient of a modulus of the calibration vector and a modulus of the calibration vector.

Define the norm of the calibration vector as r _1x The modulus of the calibration vector of the ith sensor on the j axis is r _ij Then the calibration parameter s corresponding to the calibration vector _ij-1x At least configured to satisfy:

therefore, the scaling coefficient required for correcting the modulus of the calibration vector into the calibration vector is obtained through calculation, so that different conversion coefficients are unified, and the calibration vector can be finally fitted into a reference sphere model similar to a regular sphere. Corresponding to the conversion coefficient K of the sensor i on the j axis _ij Then, there are:

K′ _ij ＝s _ij-1x K _ij ≈K _1x ；

wherein, K' _ij For the data vector corresponding to the calibration vector, K _1x The conversion coefficient corresponding to the calibration vector (in the present embodiment, the conversion coefficient corresponding to the calibration vector of the first magnetic sensor in the x-axis direction).

In this respect, in embodiments in which a plurality of magnetic sensors are arranged in the detection device, the calibration parameter s can be used _ij-1x Calibrating calibration vectors for all magnetic sensors in all axial directions to generate a data vector B' _ij Of which is a data vector B' _ij Is at least configured to satisfy:

B′ _ij ＝s _ij-1x (B _ij -ΔB _ij )；

wherein, B _ij For the i-th magnetic sensor to correspond to the output on the j-axis, Δ B _ij The offset on the j-axis is corresponding to the ith magnetic sensor.

In this embodiment, although step 3013 and step 312 are configured in a refined manner in synchronization, there is only a relationship between them that step 312 depends on the calibration parameters generated in step 3013. It is understood that step 3013 can be implemented independently of step 312 to generate a more accurate reference sphere model, and the corresponding technical effects of the specific implementation provided in step 31 can be implemented in the alternative of the foregoing embodiments.

The calibration process described above may be implemented in any process of detection.

For example, during the use process, the detection device may calculate the strength of the magnetic field in real time and determine the weak magnetic source, and in this case, when it is detected that the measurement value of a certain magnetic sensor is close to its measurement range, the operator may be indicated by a status light to express that other strong magnetic field interference (magnetic control system, large magnet, etc.) exists around, so that the use of the detection device is affected. At this moment, the alarm lamp can be configured to normally go out, avoids the wrong report to police, and the operator can avoid demarcating detecting device again behind the magnetic field interference, waits to demarcate to accomplish and detects that the magnetic field interference has got rid of the back, and alarm lamp and detection process can be restarted.

For another example, when the probe is started and initialized, or when the probe is restarted and re-calibrated after receiving a strong magnetic field, the operator may stand the probe in an environment without a significant magnetic field, or randomly shake the probe in the environment (either along the 8-letter circle or by rotating the probe) until all the calibration points are located within the corresponding spherical shell. Experimentally, the above initialization process usually requires 1-3 s.

Of course, the present invention may also provide another embodiment as shown in fig. 22 to 24, which specifically includes: tracking the condition that the distance between at least two observation points on the reference sphere model changes along with the magnetic field to obtain a distance change value; and if the distance change value and a preset distance change threshold value meet a preset quantity relationship, judging that a weak magnetic source exists in the non-magnetic cavity. Therefore, the condition of missed detection or omission caused by the fact that the size of the magnetic field generated by the weak magnetic source is not enough to enable the observation point to be arranged away from the geomagnetic field spherical shell can be prevented.

As shown in fig. 22, a fifth observation point 45 and a sixth observation point 46 may be included on the reference sphere model, and have a first interval Δ x in an initial state ₁ And form a fifth observation vector 450 and a sixth observation vector 460 corresponding to the sphere center 40, respectively. After the external magnetic field of the detecting device changes, the fifth observation point 45 moves to the first position 45 'and forms a new observation vector 450' with the center of the sphere 40 again, the sixth observation point 46 correspondingly moves to the second position 46 'and forms another new observation vector 460' with the center of the sphere 40, and the first position 45 'and the sixth position 46' have a second distance Δ x ₂ 。

Based on the above, the difference value between the first distance and the second distance can be calculated to obtain a distance change value, and the number relation between the distance change value and the corresponding distance change threshold value is judged, so that whether the weak magnetic source exists in the non-magnetic cavity or not is judged. The above technical solution can be used as a technical solution for judging whether the weak magnetic source exists alone, or can be used as a complement of the technical solution for judging whether the weak magnetic source exists by using a mode of a magnetic field observation vector. That is, if the magnitude of the magnetic field observation vector does not satisfy the predetermined magnitude relationship with the first geomagnetic radius, the above steps are further verified and determined.

Further, in another embodiment, the weak magnetic detection method may further include: tracking the dispersion conditions of at least two groups of observation point sets on the reference sphere model to obtain first dispersion data and second dispersion data, and tracking the integral dispersion conditions of the at least two groups of observation points to obtain global dispersion data which are respectively used for representing the condition that the distance between the observation points changes along with the magnetic field; and if the global dispersion data and the interval change threshold value, the first dispersion data and the second dispersion data meet a preset number relation, judging that a weak magnetic source exists in the non-magnetic cavity.

Preferably, the first dispersion data is defined as s (gro)up ₁ ) Defining the second dispersion data as s (group) ₂ ) Defining the pitch variation threshold (or dispersion tolerance) as s _th Defining the global dispersion data as s (group) ₁ ,group ₂ ,..), the global dispersion data is configured to satisfy at least:

s(group ₁ ,group ₂ ,...)>max(s(group ₁ ),s(group ₁ ),...)+s _th 。

that is, if the global dispersion data is larger than the sum of the maximum value of all the dispersion data such as the first dispersion data and the second dispersion data and the dispersion tolerance, it is determined that the entire magnetic field is disturbed by an external magnetic field (weak magnetic source or the like), and thus it is determined that the weak magnetic source exists in the nonmagnetic cavity. In such an embodiment, even if an error occurs and an outlier exists inside, the above condition is not triggered to cause a system misjudgment. The dispersion tolerance has the function of adjusting the sensitivity and the anti-interference capability of operation and judgment.

And if the global discrete data is approximately equal to or slightly smaller than the sum of the maximum value and the dispersion tolerance, judging that the whole magnetic field is not interfered by the external magnetic field. In the presence of outliers, the above conditions are still fulfilled.

Similar to the above technical solutions, the above preferred technical solutions provided by the present invention can be used as supplementary verification steps of any of the above embodiments. As an independent weak magnetic source determination method, it is possible to replace the above-described technical means for determining the presence or absence of a weak magnetic source by a modulus of a magnetic field observation vector, and it is preferable to combine any of the additional features and embodiments described above.

Specifically, as shown in fig. 23, for a single set of observation points, the observation point sets before the magnetic field change are defined to be distributed in the first region 47, and the first region 47 has a dispersion. When the set of observation points increases in the dispersion data after the magnetic field changes, the original set of observation points forms a first subset 471 and a second subset 472, which are reflected in the expansion of the first region 47 to the second region 47'. Thus, the existence of a weak magnetic source in the non-magnetic cavity can be judged.

As shown in fig. 24, for the two sets of viewpoint sets, the third region 48A shows the global distribution of the first viewpoint set 481A and the second viewpoint set 482A under the influence of the weak magnetic source, the global distribution having the global dispersion data, the first viewpoint set 481A having the first dispersion data, and the second viewpoint set 482A having the second dispersion data. At this time, the global dispersion data is larger than the sum of the maximum value in the first dispersion data and the second dispersion data and the dispersion tolerance.

The fourth region 48B shows the global distribution of the first and second sets of viewpoints 481B and 482B for another case, which has another global degree of dispersion-the distribution of the second set of viewpoints 482B is substantially unchanged, the first set of viewpoints 481B appears outliers, but because of the global degree of dispersion of the fourth region 48B, which is approximately equal to the sum of the first degree of dispersion and the dispersion tolerance of the first set of viewpoints 481B, it can be determined that there is no weak magnetic source or other external magnetic field influence at this time, and thus the influence of outliers can be better excluded.

Of course, the method provided by this embodiment may further include: and screening outliers in the at least two observation points after the change, and calculating the dispersion data according to the screened observation points.

In summary, the invention utilizes weak magnetism carried by medical equipment to detect the medical equipment in the non-magnetic cavity, and tracks the vector change condition of a certain data point in the reference sphere model under different states by fitting the reference sphere model representing the intensity of the geomagnetic field, so as to perform comparison and judgment according to a certain preset quantity relation.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.

Claims

1. A weak magnetic detection method for detecting weak magnetic medical equipment in a non-magnetic cavity is characterized by comprising the following steps:

acquiring a magnetic field observation vector formed by at least one observation point on the reference sphere model after the magnetic field changes; wherein the reference sphere model represents a geomagnetic field condition and has a first geomagnetic radius;

and if the mode of the magnetic field observation vector and the first geomagnetic radius meet a preset number relation, judging that a weak magnetic source exists in the non-magnetic cavity, and outputting a presence signal.

2. The weak magnetic detection method according to claim 1, characterized by specifically comprising:

if the modulus of the magnetic field observation vector is smaller than a first criterion value or the modulus of the magnetic field observation vector is larger than a second criterion value, judging that a weak magnetic source exists in the nonmagnetic cavity, and outputting a presence signal;

wherein the first criterion value is equal to a difference between the first geomagnetic radius and a first tolerance, and the second criterion value is equal to a sum of the first geomagnetic radius and a first tolerance, the first tolerance characterizing a difference between modes of different magnetic field vectors in the reference sphere model.

3. The weak magnetic detection method according to claim 1, further comprising:

receiving the presence signals, and acquiring the number and/or average duration of the presence signals;

and if the number and/or the average duration of the existing signals are/is greater than a preset value, outputting an alarm signal.

4. The weak magnetic detection method according to claim 1, further comprising:

receiving the existence signal, and acquiring the modes of a plurality of magnetic field observation vectors within a preset time range;

calculating the standard deviation of the modes of a plurality of magnetic field observation vectors to obtain a magnetic observation standard deviation;

and when the magnetic observation standard deviation is less than or equal to a preset dynamic magnetic field threshold value, outputting an alarm signal.

5. The weak magnetic detection method according to claim 1, characterized by specifically comprising:

acquiring a magnetic field observation vector formed by at least one observation point after the magnetic field changes on a reference sphere model and acceleration and rotation angular velocity change signals in the magnetic field change process to obtain mode, acceleration data and gyro data of the magnetic field observation vector;

the method further comprises the following steps:

receiving the existence signal, and calculating the standard deviation of the acceleration data and/or the average value of the gyro data to obtain the speed standard deviation and/or the gyro average value;

and if the speed standard deviation is less than or equal to a preset dynamic speed threshold value and/or when the gyro mean value is less than or equal to a preset dynamic rotation threshold value, outputting an alarm signal.

6. The weak magnetic detection method according to claim 1, characterized by specifically comprising:

acquiring multi-azimuth geomagnetic field data, and fitting in a three-dimensional coordinate system to obtain the reference sphere model;

calculating to obtain a multi-azimuth geomagnetic field vector according to the geomagnetic field data;

calculating to obtain a first tolerance in the preset quantity relation according to the modulus of the geomagnetic field vector;

wherein the first tolerance characterizes a difference between modes of different magnetic field vectors in the reference sphere model, the geomagnetic field vectors being configured as directed line segments pointing from a center of sphere of the reference sphere model to a location of the geomagnetic field data in the three-dimensional coordinate system; the first tolerance is configured as an integer multiple of a standard deviation of a modulus of the earth-magnetic field vector.

7. The weak magnetic detection method according to claim 1, further comprising:

acquiring geomagnetic field data of a plurality of magnetic sensors in multiple directions, and fitting a plurality of sphere models in a three-dimensional coordinate system to obtain a plurality of calibration sphere models;

calculating the center of the calibration sphere model and the vector from the center of the reference sphere model to the calibration point to obtain a plurality of calibration centers and calibration vectors;

calibrating a plurality of calibration vector models by using a calibration vector of one of the plurality of calibration sphere models to obtain a plurality of data vectors;

calculating to obtain a plurality of data points according to the data vectors and the corresponding calibration sphere centers, and fitting a reference sphere model in a three-dimensional coordinate system according to the data points;

distributing the magnetic field data on the calibration sphere model to form a plurality of calibration points; the calibration vector is a calibration vector of one of the calibration sphere models in a preset direction;

the method specifically comprises the following steps:

obtaining a vector corresponding to the observation point in a first state to obtain a first observation vector;

acquiring a vector corresponding to the observation point in a second state, and calibrating by using the calibration vector to obtain a second observation vector;

and if the modulus of the second observation vector and the first geomagnetic radius meet a preset quantitative relation, judging that the weak magnetic source exists in the non-magnetic cavity, and outputting the existence signal.

8. The weak magnetic detection method according to claim 7, wherein the calibration sphere model is an ellipsoid, the preset direction is a long axis direction of the ellipsoid, and the method specifically comprises:

calculating to obtain a plurality of calibration parameters according to the calibration vectors and the models of the plurality of calibration vectors; wherein the calibration parameter is a quotient of a modulus of the calibration vector and a modulus of the calibration vector;

respectively calibrating the modes of the calibration vectors according to the calibration parameters to obtain a plurality of data vectors;

the method specifically comprises the following steps:

acquiring calibration parameters corresponding to the first observation vector to obtain observation calibration parameters;

and acquiring a vector corresponding to the observation point in the second state, and calibrating by using the observation calibration parameters to obtain a second observation vector.

9. The weak magnetic detection method according to claim 1, further comprising:

if the mode of the magnetic field observation vector does not meet the preset quantitative relation with the first geomagnetic radius, tracking the condition that the distance between at least two observation points on the reference sphere model changes along with the magnetic field to obtain a distance change value;

and if the distance change value and a preset distance change threshold value meet a preset quantity relationship, judging that a weak magnetic source exists in the nonmagnetic cavity.

10. The weak magnetic detection method according to claim 9, further comprising:

tracking the dispersion conditions of at least two groups of observation point sets on the reference sphere model to obtain first dispersion data and second dispersion data, and tracking the integral dispersion conditions of the at least two groups of observation points to obtain global dispersion data which are respectively used for representing the condition that the distance between the observation points changes along with the magnetic field;

if the global dispersion data and the preset interval change threshold value, the first dispersion data and the second dispersion data meet the preset quantity relationship, the weak magnetic source in the non-magnetic cavity is judged.

11. An endoscopic probe for probing an endoscope within a human body, the endoscope configured to have weak magnetic properties, the endoscopic probe comprising a probing panel comprising a display surface and a sensing surface disposed opposite each other, and a handle connected to the probing panel, the endoscopic probe configured to implement the weak magnetic probing method of claims 1-10.

12. The endoscopic probe according to claim 11, wherein said display surface is provided with an alarm light and a status light configured in a ring shape, said sensing surface having at least four sensing units distributed uniformly thereon, said sensing units comprising at least two magnetic sensors, one of said magnetic sensors being disposed on a side close to a geometric center of said sensing surface, and the other of said magnetic sensors being disposed on a side away from said geometric center.