Navigation positioning method, device, system and computer program product

Abstract

The invention provides a navigation positioning method, device and system and a computer program product. The method comprises the following steps: acquiring a CT image of a first skin area; acquiring first position data of the plurality of markers under the first coordinate system; determining a second conversion relation between the second coordinate system and the third coordinate system according to the CT image, the first position data and the first conversion relation; the second coordinate system comprises a coordinate system of the mechanical arm, the third coordinate system comprises a coordinate system of the CT image, and the first conversion relation comprises a conversion relation between the first coordinate system and the second coordinate system; determining third position data of the target puncture position under the second coordinate system according to second position data of the target puncture position under the third coordinate system and the second conversion relation; the third position data is used for determining a control instruction of the mechanical arm so as to control the mechanical arm to move to the target puncture position. According to the scheme, the mechanical arm can be accurately navigated and positioned, and the efficiency of a puncture operation is improved.

Description

Technical Field

[0001] The present application relates to the field of medical device technology, and in particular to a navigation and positioning method, device, system and computer program product. Background Art

[0002] Percutaneous puncture surgery is a surgical technique that inserts a puncture needle into the patient's skin to reach the lesion (or target point). Percutaneous puncture surgery is usually performed with the assistance of imaging technology (such as ultrasound, CT, etc.) to ensure accurate positioning of the target point. At present, a robotic arm can be combined to assist in puncture. The movement process of the robotic arm can be displayed in real time under the CT image. During the puncture process, the doctor can view the CT image to determine the location of the target point and control the robotic arm to move toward the target point.

[0003] However, the appearance of the robotic arm is wrapped in metal, which will produce metal artifacts in the CT image, affecting the accuracy of the robotic arm's navigation and positioning. In addition, every time the robotic arm moves a certain distance, a new CT scan is required to determine whether the needle insertion point and direction are consistent with the surgical plan. This process greatly increases the operation time and reduces the efficiency of the puncture surgery. Summary of the invention

[0004] The embodiments of the present application provide a navigation and positioning method, device, system and computer program product to improve the accuracy of navigation and positioning of a robotic arm and improve the efficiency of puncture surgery.

[0005] In a first aspect, a navigation and positioning method is provided, which is applied to a robotic arm, wherein the robotic arm is used for a puncture process of a first skin area of ​​a patient, wherein the first skin area includes a target puncture position, and a plurality of markers are arranged on the first skin area, and the method comprises:

[0006] acquiring a CT image of a first skin area;

[0007] Acquiring first position data of a plurality of markers in a first coordinate system; the navigation device is used to locate the plurality of markers;

[0008] Determine a second conversion relationship between the second coordinate system and the third coordinate system according to the CT image, the first position data, and the first conversion relationship; the second coordinate system includes a coordinate system of the robot arm, the third coordinate system includes a coordinate system of the CT image, and the first conversion relationship includes a conversion relationship between the first coordinate system and the second coordinate system;

[0009] According to the second position data of the target puncture position in the third coordinate system and the second conversion relationship, the third position data of the target puncture position in the second coordinate system is determined; the third position data is used to determine the control instruction for controlling the robot arm to move to the target puncture position.

[0010] In one implementation, determining a second transformation relationship between the second coordinate system and the third coordinate system according to the CT image, the first position data, and the first transformation relationship includes:

[0011] Determining fourth position data of the plurality of markers in a third coordinate system according to the CT image;

[0012] determining a third conversion relationship between the first coordinate system and the third coordinate system according to the fourth position data and the first position data;

[0013] A second conversion relationship is determined according to the first conversion relationship and the third conversion relationship.

[0014] In one implementation, determining a second conversion relationship between the first coordinate system and the third coordinate system according to the fourth position data and the first position data includes:

[0015] Decentralizing the fourth position data to determine fifth position data;

[0016] Decentralizing the first position data to determine sixth position data;

[0017] Determine a covariance matrix according to the fifth position data and the sixth position data;

[0018] A second conversion relationship is determined according to the covariance matrix, the fifth position data, and the sixth position data.

[0019] In one implementation, determining the second conversion relationship according to the covariance matrix, the fifth position data, and the sixth position data includes:

[0020] Determine a first eigenvalue matrix and a second eigenvalue matrix according to the covariance matrix;

[0021] Determine a rotation matrix between the first coordinate system and the third coordinate system according to the first eigenvalue matrix and the second eigenvalue matrix;

[0022] an offset between the first coordinate system and the third coordinate system according to the rotation matrix, the fifth position data, and the sixth position data;

[0023] A second transformation relationship is determined according to the rotation matrix and the offset.

[0024] In one implementation, the rotation matrix is ​​determined according to the following formula:

[0025]

[0026] Where R represents the rotation matrix, λ L represents the first characteristic matrix, λ R represents the second characteristic matrix, T represents matrix transpose;

[0027] The offset is determined according to the following formula:

[0028] t=P′ N -P′ P *R;

[0029] Wherein, t represents the offset, P' P Represents the fifth position data, P' N Represents the sixth position data.

[0030] In one implementation, the number of the multiple markers is greater than or equal to 3, and the multiple markers are asymmetrically arranged around the target puncture position.

[0031] In one implementation, the plurality of markers include a first marker and a second marker, and a distance between the first marker and the second marker is greater than or equal to a preset distance.

[0032] In a second aspect, a navigation and positioning device is provided, which is applied to a robotic arm, and the robotic arm is used for a puncture process of a first skin area of ​​a patient, the first skin area includes a target puncture position, and a plurality of markers are arranged on the first skin area, and the device includes:

[0033] A first interface, coupled to the navigation device, configured to receive first location data sent by the navigation device;

[0034] A second interface, coupled to the scanning device, is configured to receive the CT image sent by the scanning device;

[0035] The processor is coupled to the first interface and the second interface, and is configured to execute the above first aspect or any one of the methods implemented in the first aspect.

[0036] In a third aspect, a navigation and positioning system is provided, which is applied to a robotic arm, the robotic arm including a positioning device, the robotic arm being used for a puncture process of a first skin area of ​​a patient, the first skin area including a target puncture position, and a plurality of markers being arranged on the first skin area, the navigation and positioning system including:

[0037] a navigation device configured to locate a plurality of markers and a positioning device;

[0038] A terminal comprises the device of the second aspect above.

[0039] According to a fourth aspect, a computer program product is provided, comprising instructions, wherein when the instructions are called by a processor, the above first aspect or any one of the methods implemented in the first aspect is executed.

[0040] Compared with the prior art, the beneficial effects of this application are:

[0041] (1) The solution of the present application sets a marker in the patient's skin area to reduce the appearance of metal artifacts of the robotic arm in the CT image. The position data of the marker can be used to establish a coordinate system joint relationship between the CT image, the navigation device, and the robotic arm, so that the position data of the robotic arm relative to the target puncture point can be determined. In this way, even if the robotic arm is not displayed in real time (for example, the robotic arm is outside the scanning field of view of the scanning device), the robotic arm can be accurately positioned, and the metal artifacts in the CT image can be reduced to improve the quality of the CT image.

[0042] (2) The solution of the present application can also be used to automatically plan the movement path of the robotic arm. The robotic arm can automatically move to the appropriate position according to the control instructions. There is no need for repeated CT scans, and the doctor does not need to manually adjust the robotic arm, which saves operation time and improves the efficiency of puncture surgery. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The following is a brief introduction to the drawings used in describing the embodiments of this application:

[0044] Figure 1 A schematic diagram of the structure of a navigation and positioning system provided in some embodiments of the present application;

[0045] Figure 2 A flowchart of a navigation and positioning method provided in some embodiments of the present application;

[0046] Figure 3 A schematic diagram of the structure of a navigation device provided in some embodiments of the present application;

[0047] Figure 4 A schematic diagram of the structure of a navigation and positioning device provided in some embodiments of the present application. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. The accompanying drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other accompanying drawings and other embodiments can be obtained based on these accompanying drawings without creative work. Adjustments and improvements made without departing from the concept of the present application are all within the scope of protection of the present application.

[0049] In order to simplify the drawings, each of the drawings schematically shows only the parts related to the corresponding embodiments, and they do not represent the actual structure of the product, and there may be more or fewer structures or components in reality. In addition, in order to simplify the drawings and facilitate understanding, for the structures or components shown in the drawings, there may be more or fewer similar structures or components in reality.

[0050] In this application, unless otherwise clearly specified and limited, ordinal numbers, such as "first", "second", etc., are only used to distinguish and describe associated objects, and cannot be understood as indicating or implying the relative importance or order between associated objects. For example, the first position data may include one position data or multiple position data. In addition, ordinal numbers do not represent the number of associated objects. "Multiple" includes two or more, and other quantifiers are similar. " / " is used to describe the relationship between associated objects, which represents the "or" relationship between associated objects. "And / or" is used to describe the relationship between associated objects, which includes any combination relationship between associated objects, such as "a and / or b" includes: "alone a", "alone b", or "a and b". "One or more" or "at least one" in multiple objects refers to any object or any combination of multiple objects, such as "one or more of a1, a2, a3" or "at least one of a1, a2, a3" includes: "alone a1", "alone a2", "alone a3", "a1 and a2", "a1 and a3", "a2 and a3", or "a1, a2 and a3".

[0051] In the embodiments of the present application, "connection" includes direct or indirect connection between objects, which may be directly connected through a medium (e.g., a wire, a trace, etc.), or indirectly connected through other elements, or internally connected. Similarly, "coupling" includes signal connection between objects, which may be directly connected through a medium (e.g., a wire, a trace, etc.), or may be connected through other elements, etc.

[0052] Percutaneous puncture surgery is a surgical technique that inserts a puncture needle into the patient's skin to reach the lesion (or target point). It is widely used in a variety of medical procedures (such as cardiovascular angiography, tumor ablation, etc.). Percutaneous puncture surgery is usually performed with the assistance of imaging technology (such as ultrasound, CT, etc.) to ensure accurate positioning of the target point. Currently, a robotic arm can be combined to assist in puncture.

[0053] Please refer to Figure 1 , which is a structural diagram of a navigation and positioning system provided in an embodiment of the present application. Figure 1As shown, the navigation and positioning system 100 includes a navigation device 110 and a terminal 120. The navigation device 110 can track and locate the mechanical arm 20 and obtain the position data of the mechanical arm 20 relative to the navigation device 110. The navigation device 110 and the terminal 120 are coupled, and the position data of the mechanical arm 20 can be sent to the terminal 120. The terminal 120 is also coupled to the scanning device 10. The scanning device 10 can perform a computed tomography (CT) scan on the patient and collect the CT image of the patient (for example, a CT image of the skin area). The terminal 120 can receive the CT image sent by the scanning device 10 and display the CT image. In one implementation, the movement process of the mechanical arm can be displayed in real time under the CT image, for example, the mechanical arm is located in the scanning field of view of the scanning device, and the CT scan can be performed simultaneously with the skin area. The terminal 120 can use the position data and the CT image sent by the navigation device 110 to perform coordinate system registration on the CT image and the mechanical arm, so as to achieve accurate correspondence between the display of the mechanical arm in the CT image and the actual mechanical arm. In this way, the doctor can plan the puncture surgery path based on the CT image, and manually control the movement of the robotic arm 20 through the terminal 120 so that the final posture position of the robotic arm is consistent with the surgical plan.

[0054] However, in order to ensure the rigidity of the robotic arm, the appearance of the robotic arm is wrapped in metal, which will produce metal artifacts in the CT image. Metal artifacts will interfere with the recognition of CT images, affect the doctor's positioning judgment of the robotic arm, and reduce the accuracy of the robotic arm's navigation positioning. In addition, the control process of the robotic arm is relatively complicated and requires a high level of operation from the doctor; and every time the robotic arm moves a certain distance, a CT scan needs to be performed again to determine whether the needle insertion point and direction are consistent with the surgical plan. This process greatly increases the operation time and reduces the efficiency of the puncture surgery.

[0055] Based on this, the embodiments of the present application provide a method, device, system and other solutions for navigation and positioning, which can reduce the metal artifacts of the robotic arm in the CT image by setting a marker in the patient's skin area, and use the position data of the marker to establish a coordinate system joint relationship between the CT image, the navigation device and the robotic arm, so as to determine the position data of the robotic arm relative to the target puncture point. In this way, even if the robotic arm is not developed in real time (for example, the robotic arm is outside the scanning field of view of the scanning device), the robotic arm can be accurately positioned, and the metal artifacts in the CT image can be reduced to improve the quality of the CT image.

[0056] The following is a description with reference to the accompanying drawings.

[0057] Please refer to Figure 2 , which is a flowchart of a navigation positioning method provided in an embodiment of the present application. Figure 2As shown, the navigation positioning method at least includes the following steps:

[0058] S210: Acquire a CT image of a first skin area;

[0059] S220: Acquire first position data of a plurality of markers in a first coordinate system; the navigation device is used to locate the plurality of markers;

[0060] S230: determining a second conversion relationship between a second coordinate system and a third coordinate system according to the CT image, the first position data, and the first conversion relationship; the second coordinate system includes a coordinate system of the robot arm, the third coordinate system includes a coordinate system of the CT image, and the first conversion relationship includes a conversion relationship between the first coordinate system and the second coordinate system;

[0061] S240: Determine third position data of the target puncture position in the second coordinate system according to the second position data of the target puncture position in the third coordinate system and the second conversion relationship; the third position data is used to determine a control instruction for controlling the robot arm to move to the target puncture position.

[0062] Please continue to refer to Figure 1 , Figure 1 The marker 30 can be set on the patient's skin area to be scanned so that the marker 30 falls into the scanning field of view of the scanning device. For the sake of distinction, the skin area to be scanned can be referred to as the first skin area, and the first skin area includes the target puncture position (such as the lesion point). The robotic arm 20 can be used for the puncture process of the patient's first skin area. The navigation device 110 can locate the robotic arm 20 and the marker 30. In one implementation, the navigation device includes an electromagnetic navigation device. The marker includes an electromagnetic sensor, such as an electromagnetic induction coil. For example, the marker is a circular patch that contains an electromagnetic induction coil. Please refer to Figure 3 , which is a schematic diagram of the structure of a navigation device provided in an embodiment of the present application. Figure 3As shown, the navigation device 300 includes a magnetic field generator 310 and a control unit 320. When the marker 30 is located in the magnetic field generated by the magnetic field generator 310, the electromagnetic induction coil inside the marker 30 generates an induced voltage. The marker 30 is coupled to the control unit 320, and the marker 30 can convert the induced voltage into a digital signal and send it to the control unit 320. The control unit 320 can parse the received digital signal to obtain the position data of the marker 30. In one implementation, the marker 30 may include a plurality of markers. Each marker may include an electromagnetic sensor and is located by the navigation device 300 through the above process. For example, the plurality of markers are asymmetrically arranged around the target puncture position. For example, the number of the plurality of markers is greater than or equal to 3. For example, the plurality of markers include a first marker and a second marker. The distance between the first marker and the second marker is greater than or equal to a preset distance. For example, the spacing distance between any two markers in the plurality of markers is greater than or equal to a preset distance (e.g., 2 mm).

[0063] For ease of distinction, the coordinate system of the navigation device may be referred to as the first coordinate system, the coordinate system of the robotic arm may be referred to as the second coordinate system, and the coordinate system of the CT image may be referred to as the third coordinate system.

[0064] Multiple markers can be located by the navigation device, and the navigation device can generate position data (which may be referred to as first position data) of the multiple markers in a first coordinate system. The position data includes, for example, position coordinates. In one implementation, the conversion relationship R1 (which may be referred to as the first conversion relationship) between the navigation device coordinate system and the manipulator coordinate system is known, then based on the CT image, the first position data and the first conversion relationship, the navigation device coordinate system, the manipulator coordinate system and the CT image coordinate system can be combined to determine the conversion relationship R2 (which may be referred to as the second conversion relationship) between the manipulator coordinate system and the CT image coordinate system.

[0065] Through the conversion relationship R2, the position data of the target puncture position in the CT image coordinate system (which may be referred to as the second position data) can be converted into the position data of the target puncture position in the robotic arm coordinate system (which may be referred to as the third position data). The conversion relationship may include one or more of the rotation matrix and the offset between any two coordinate systems. The third position data can be used to determine the path of the robotic arm to move to the target puncture position. For example, the third position data includes the position coordinates and direction vector of the target puncture position in the robotic arm coordinate system. Based on the third position data, the relative distance and rotation relationship between the robotic arm and the target puncture position can be determined. Based on the relative distance and rotation relationship, combined with the kinematic model of the robotic arm, the moving path of the robotic arm can be determined. Based on the moving path, a control instruction can be generated, and after receiving the control instruction, the robotic arm can move to the target puncture position and the posture is consistent with the surgical plan.

[0066] In this way, by setting a marker that can be located by the navigation device in the patient's skin area, the position data of the marker is used to establish a joint relationship between the coordinate systems of the CT image, the navigation device and the robotic arm. Even if the robotic arm does not enter the scanning field of view of the scanning device, the CT image can be accurately aligned with the robotic arm, and the metal artifacts in the CT image can be reduced, thereby improving the quality of the CT image. Furthermore, the solution provided in the present application can also be used to automatically plan the movement path of the robotic arm. The robotic arm can automatically move to the appropriate position according to the control instructions, without the need for repeated CT scans and the need for the doctor to manually adjust the robotic arm, thereby saving operation time and improving the efficiency of puncture surgery.

[0067] In one implementation, the first conversion relationship R1 can be predetermined and stored in the terminal so that it can be directly called during the puncture process to further improve efficiency. Figure 3 As shown, the mechanical arm 20 may be provided with a positioning device 21, and the navigation device 300 may also be used to position the positioning device 21. The first conversion relationship R1 may be determined by using the positioning device provided on the mechanical arm, for example: obtaining position data of the positioning device in a first coordinate system; obtaining position data of the positioning device in a second coordinate system; and determining the first conversion relationship based on the two position data. For example, the positioning device may be provided at the end of the mechanical arm.

[0068] The process of determining the second conversion relationship is described below.

[0069] exist Figure 2 Based on the embodiments thereof, determining the second transformation relationship between the second coordinate system and the third coordinate system according to the CT image, the first position data, and the first transformation relationship includes:

[0070] S231: determining fourth position data of a plurality of markers in a third coordinate system according to the CT image;

[0071] S232: determining a third conversion relationship between the first coordinate system and the third coordinate system according to the fourth position data and the first position data;

[0072] S233: Determine a second conversion relationship according to the first conversion relationship and the third conversion relationship.

[0073] The plurality of markers are arranged on the first skin area and can be developed on the CT image of the first skin area. The position data P of the plurality of markers in the CT image coordinate system can be determined by the CT image. P (may be referred to as fourth position data). According to the position data P P And the position data P of the marker in the navigation device coordinate system N, the conversion relationship R3 (which can be called the third conversion relationship) between the navigation device coordinate system and the CT image coordinate system can be determined. In addition, the conversion relationship R1 between the navigation device coordinate system and the manipulator coordinate system is determined. In this way, according to the conversion relationship R1 and the conversion relationship R3, the joint relationship between the navigation device coordinate system, the CT image coordinate system, and the manipulator coordinate system can be established, thereby determining the second conversion relationship.

[0074] The following is the above position data P P and position data P N , the process of determining the conversion relationship R3 is described. Position data P P The position data P includes a set of position coordinates of multiple markers in the CT image coordinate system. N A collection of position coordinates of multiple markers in the navigation device coordinate system. For example, the position data can be represented in the form of a matrix:

[0075]

[0076] Wherein, x, y, z represent the coordinate values ​​of each coordinate axis of the marker in the coordinate system, and n represents the number of markers (n≥3). The embodiment of the present application does not limit the coordinate axes of each coordinate system. For example, the positive direction of the x-axis of the robot end coordinate system is directly in front of the robot base, the positive direction of the y-axis is vertically downward, and the positive direction of the z-axis is to the right of the robot base. The positive direction of the x-axis of the navigation device coordinate system is vertically downward, the y-axis is the same as the direction of the magnetic field, and the z-axis is perpendicular to the direction of the magnetic field. The positive direction of the x-axis of the CT image coordinate system is to the right, the positive direction of the y-axis is downward, and the z-axis is the slice direction of the image. The positive direction of the x-axis of the patient coordinate system is the left side of the patient, the positive direction of the y-axis is vertically downward, and the z-axis is parallel to the patient's body.

[0077] In one implementation, based on the position data P P and position data P N , determine the conversion relationship R3, including: P Decentralize the processing to determine the fifth position data; N Decentralization is performed to determine the sixth position data; a covariance matrix is ​​determined based on the fifth position data and the sixth position data; and a third conversion relationship is determined based on the covariance matrix, the fifth position data and the sixth position data. The specific process is as follows:

[0078] The following formula can be used to determine the position coordinates C of the geometric centers of multiple markers:

[0079]

[0080] According to the location data P P, the position coordinates of the geometric centers of multiple markers in the CT image coordinate system can be determined, denoted as C P According to the position data P N , the position coordinates of the geometric centers of multiple markers in the navigation device coordinate system can be determined, denoted as C N . Position data P P and position data P N After decentralization, the location data P' can be obtained P (may be referred to as the fifth position data) and position data P' N (may be called the sixth position data):

[0081] P′ P =P P -C P ;

[0082] P′ N =P N -C N ;

[0083] According to the position data P' P and position data P' N The covariance matrix cov of these two sets of coordinate points can be calculated NP :

[0084]

[0085] Where T represents the matrix transpose.

[0086] For example, according to the covariance matrix cov NP , fifth position data P' P and the sixth position data P' N , the third transformation relationship can be determined. For example, according to the covariance matrix, the first eigenvalue matrix and the second eigenvalue matrix are determined; according to the first eigenvalue matrix and the second eigenvalue matrix, the rotation matrix between the first coordinate system and the third coordinate system is determined; according to the rotation matrix, the fifth position data, and the sixth position data, the offset between the first coordinate system and the third coordinate system is determined; according to the rotation matrix and the offset, the third transformation relationship is determined. The specific process is as follows:

[0087]

[0088] |A-λ L *I|=0;

[0089] |A-λ R *I|=0;

[0090] Among them, λ L represents the left eigenvalue matrix of the difference matrix (which can be called the first eigenvalue matrix), λR represents the right eigenvalue matrix of the covariance matrix (which may be called the second eigenvalue matrix), and I represents the identity matrix.

[0091] According to the eigenvalue matrix λ L and the eigenvalue matrix λ R , the rotation matrix R between the navigation device coordinate system and the CT image coordinate system can be determined:

[0092]

[0093] Among them, the first row of the rotation matrix R represents the parameters of the rotation of the CT image coordinate system around its own x-axis, the second row represents the parameters of the rotation of the CT image around its own y-axis, and the third row represents the parameters of the rotation of the CT image around its own z-axis.

[0094] According to the rotation matrix R, position data P' R , position data P' N , the offset t between the navigation device coordinate system and the CT image coordinate system can be determined:

[0095]

[0096] Among them, t x1 is the offset of the CT image on the x-axis, t y1 is the offset of the CT image on the y axis, t z1 is the offset of the CT image on the z-axis.

[0097] According to the above rotation matrix R and offset T, the conversion relationship R3 (denoted as Rt PN ):

[0098]

[0099] Since both coordinate systems are rigid transformations, the last row of the matrix is ​​[0 0 0 1].

[0100] The position data may also include a direction vector. The position data of the target puncture position in the CT image coordinate system (ie, the second position data) includes the position coordinate P Nd and direction vector V Nd The second conversion relationship is R2 = R3*R1, let R2 = Rt PR In this way, the position coordinates P Nd and direction vector V Nd Convert to the robot arm coordinate system to obtain the position data of the target puncture position in the robot arm coordinate system (i.e. the third position data mentioned above):

[0101] P' Nd =PNd *R PR =[t x2 t y2 t z2 1];

[0102] V' Nd =V Nd *R PR =[v x2 v y2 v z2 1];

[0103] Among them, P' Nd t in x2 ,t y2 ,t z2 V' is the distance the robot needs to move on the x, y, and z axes. Nd v x2 、v y2 、v z2 is the target direction vector of the robot arm. For example, P' Nd It can include the position coordinates of any point or position on the robot arm, such as the position coordinates of the end of the robot arm. Nd P' Nd The corresponding direction vector, V' Nd It can include the target direction vector of any point or position on the robot arm, such as the target direction vector of the end of the robot arm. Nd and V' Nd It can be used to determine the control instructions for controlling the robot arm to move to the target puncture position. After receiving the control instructions, the robot arm can move to the target puncture position and the posture is consistent with the surgical plan.

[0104] The following is an explanation of the above navigation and positioning process with specific data:

[0105] (1) Obtain the coordinate set of the marker in the CT image and the coordinate set in the navigation device coordinate system. The input is as follows:

[0106]

[0107] (2) Calculate P P and P N The result of the collection center is as follows:

[0108] C P =[124.3 47.9 41.9];

[0109] C N =[6.6 -19.0 58.7];

[0110] (3) PP and P N After decentralization, the results are as follows:

[0111]

[0112] (4) Calculate the covariance matrix of the two sets of points, and the result is as follows:

[0113]

[0114] (5) Calculate the left eigenvalue matrix, the result is as follows:

[0115]

[0116] (6) Calculate the right eigenvalue matrix, the result is as follows:

[0117]

[0118] (7) Calculate the rotation relationship between the CT image coordinate system and the navigation device coordinate system. The result is as follows:

[0119]

[0120] (8) Calculate the coordinate offset between the CT image coordinate system and the navigation device coordinate system. The result is as follows:

[0121]

[0122] (9) Through the calculations in the previous two steps, the mapping relationship between the CT image coordinate system and the navigation device coordinate system is established. The results are as follows:

[0123]

[0124] (10) Establish the mapping relationship between the coordinate system of the robot arm and the navigation device. The result is as follows:

[0125]

[0126] (11) Establish the mapping relationship between the CT image coordinate system and the robotic arm coordinate system. The results are as follows:

[0127]

[0128] (12) Obtain the target point and target direction vector of the robot arm motion under the CT image. The results are as follows:

[0129] P Nd =[3.8 13.0 43.2];

[0130] V Nd=[0.7466 0.3937 -0.5363];

[0131] (13) The sum in the CT image coordinate system is converted to the robotic arm coordinate system, and the result is as follows:

[0132] P′ Nd =[105.1 154.9 97.0 1];

[0133] V′ Nd =[0.3333 0.7957 0.5057 1];

[0134] In one implementation, the terminal may further include a mechanical arm control unit. The mechanical arm control unit may be configured to generate a plurality of mechanical arm control units based on the third position data (eg, the position coordinate P' Nd and direction vector V' Nd ) generates control instructions. Figure 1 As shown, the terminal 120 can send a control instruction to the robotic arm 20 to control the robotic arm 20 to automatically move to the target puncture position and the posture of the robotic arm 20 is consistent with the surgical plan. During the movement of the robotic arm, there is no need to repeatedly scan to determine the real-time position of the robotic arm, nor does the doctor need to manually adjust the posture or position of the robotic arm, which shortens the operation time and improves the efficiency of the puncture operation.

[0135] Based on the same technical concept, the present application also provides a navigation and positioning device. Figure 4 , which is a schematic diagram of the structure of a navigation and positioning device provided in an embodiment of the present application. The device 400 is applied to a robotic arm, and the robotic arm is used for the puncture process of a first skin area of ​​a patient. The first skin area includes a target puncture position, and a plurality of markers are set on the first skin area. Figure 4The navigation and positioning device 400 includes a first interface 410, a second interface 420 and a processor 430. The first interface 410 is coupled to a navigation device and is configured to receive first position data sent by the navigation device; the second interface 420 is coupled to a scanning device and is configured to receive a CT image sent by the scanning device; the processor 430 is coupled to the first interface 410 and the second interface 420 and is configured to execute the navigation and positioning method in any of the above embodiments. For relevant contents such as markers and first position data, reference may be made to the description of the aforementioned embodiments. In one implementation, the processor 430 is a circuit with signal processing capabilities. For example, a central processing unit (CPU), a microcontroller (MCU), a microprocessor unit (MPU), a graphics processing unit (GPU), or a digital signal processor (DSP). The present application is not limited to the type of processor.

[0136] The present application also provides a navigation and positioning system. Figure 1 The system 100 shown, the navigation and positioning system 100 is applied to a robot arm 20, the robot arm 20 includes a positioning device, and the robot arm 20 is used for the puncture process of the first skin area of ​​the patient. The first skin area includes a plurality of markers. The system 100 includes a navigation device 110 and a terminal 120. The navigation device 110 is used to locate a plurality of markers and the positioning device. For the positioning process of the navigation device, reference can be made to the description of the aforementioned embodiment. The terminal 120 includes the navigation and positioning device in the aforementioned embodiment. By way of example, the terminal 120 is a workstation.

[0137] An embodiment of the present application further provides a computer program product, comprising instructions, and when the instructions are called by a processor, the navigation and positioning method of any of the above embodiments is executed.

[0138] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. In addition, the above embodiments can be freely combined as needed.

Claims

1. A navigation positioning method, characterized in that: Applied to a robotic arm, the robotic arm is used for a puncture process of a first skin area of ​​a patient, the first skin area includes a target puncture position, and a plurality of markers are arranged on the first skin area, the method comprising: acquiring a CT image of the first skin area; Acquiring first position data of the multiple markers in a first coordinate system; the navigation device is used to locate the multiple markers; Determine a second conversion relationship between a second coordinate system and a third coordinate system according to the CT image, the first position data, and the first conversion relationship; the second coordinate system includes a coordinate system of the robot arm, the third coordinate system includes a coordinate system of the CT image, and the first conversion relationship includes a conversion relationship between the first coordinate system and the second coordinate system; According to the second position data of the target puncture position in the third coordinate system and the second conversion relationship, the third position data of the target puncture position in the second coordinate system is determined; the third position data is used to determine the control instruction for controlling the robot arm to move to the target puncture position.

2. The method according to claim 1, characterized in that The determining of the second conversion relationship between the second coordinate system and the third coordinate system according to the CT image, the first position data, and the first conversion relationship includes: Determining fourth position data of the plurality of markers in the third coordinate system according to the CT image; determining a third conversion relationship between the first coordinate system and the third coordinate system according to the fourth position data and the first position data; The second conversion relationship is determined according to the first conversion relationship and the third conversion relationship.

3. The method according to claim 2, characterized in that The determining, according to the fourth position data and the first position data, a third conversion relationship between the first coordinate system and the third coordinate system comprises: Decentralizing the fourth position data to determine fifth position data; Decentralizing the first position data to determine sixth position data; Determining a covariance matrix according to the fifth position data and the sixth position data; The third conversion relationship is determined according to the covariance matrix, the fifth position data and the sixth position data.

4. The method according to claim 3, characterized in that: The determining of the third conversion relationship according to the covariance matrix, the fifth position data and the sixth position data comprises: Determine a first eigenvalue matrix and a second eigenvalue matrix according to the covariance matrix; Determine a rotation matrix between the first coordinate system and the third coordinate system according to the first eigenvalue matrix and the second eigenvalue matrix; determining an offset between the first coordinate system and the third coordinate system according to the rotation matrix, the fifth position data, and the sixth position data; The third conversion relationship is determined according to the rotation matrix and the offset.

5. The method according to claim 4, characterized in that The rotation matrix is ​​determined according to the following formula: Where R represents the rotation matrix, λ L represents the first characteristic matrix, λ R represents the second characteristic matrix, T represents matrix transpose; The offset is determined according to the following formula: t=P’ N -P’ P *R; Wherein, t represents the offset, P' P Represents the fifth position data, P' N Represents the sixth position data.

6. The method according to any one of claims 1 to 5, characterized in that: The number of the multiple markers is greater than or equal to 3, and the multiple markers are asymmetrically arranged around the target puncture position.

7. The method according to claim 6, characterized in that The plurality of markers include a first marker and a second marker, and a distance between the first marker and the second marker is greater than or equal to a preset distance.

8. A navigation and positioning device, characterized in that: Applied to a robotic arm, the robotic arm is used for a puncture process of a first skin area of ​​a patient, the first skin area includes a target puncture position, and a plurality of markers are arranged on the first skin area, the device comprises: A first interface, coupled to the navigation device, configured to receive first position data sent by the navigation device; A second interface, coupled to the scanning device, is configured to receive the CT image sent by the scanning device; A processor, coupled to the first interface and the second interface, is configured to execute the method according to any one of claims 1 to 7.

9. A navigation and positioning system, characterized in that: Applied to a robotic arm, the robotic arm includes a positioning device, the robotic arm is used for a puncture process of a first skin area of ​​a patient, the first skin area includes a target puncture position, and a plurality of markers are arranged on the first skin area, the navigation and positioning system includes: a navigation device configured to locate the plurality of markers and the positioning device; A terminal comprising the device as claimed in claim 8.

10. A computer program product, characterized in that The method comprises instructions, and when the instructions are called by a processor, the method according to claims 1-7 is executed.

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