Surgical navigation equipment precision test system

Abstract

The invention discloses a precision test system for surgical navigation equipment. The precision measurement of the navigation equipment is realized mainly based on a laser tracker and a target ball matched with the laser tracker. The measuring method comprises the following steps: acquiring a transformation matrix from a scanning image coordinate system to a mechanical arm coordinate system; controlling the mechanical arm to move according to the starting point and the ending point on the scanning image and the conversion matrix; and calculating coordinates of a starting point and an end point actually reached by the mechanical arm under the laser tracker coordinate system based on the target ball at the tail end of the mechanical arm, and obtaining the equipment precision by combining the coordinates of the starting point and the end point in the precision test tool actually measured by the laser tracker. The method does not depend on specific optical measurement equipment, and provides the possibility of precision test for a surgical navigation system without the optical measurement equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical navigation robots, and more particularly to a surgical navigation equipment accuracy testing system. Background Art

[0002] Surgical navigation equipment plays an increasingly important role in the medical field, especially in puncture surgery. The equipment can assist doctors in accurate surgical planning and guide surgical tools to the target position through actuators such as robotic arms, thereby improving the accuracy and safety of the surgery.

[0003] System accuracy is one of the key indicators for evaluating the performance of surgical navigation equipment, which directly affects the success rate and safety of the operation. At present, the system accuracy test of surgical navigation equipment mainly adopts the method based on optical measurement equipment.

[0004] This method uses an optical measurement device to measure the actual position of the robot arm, and uses the entry point and target point of the surgical path as the actual puncture measurement value. At the same time, the optical measurement device is used to measure the test entry point and target point on the test fixture as the theoretical value measurement value. Finally, the system accuracy of the surgical navigation device is evaluated by calculating the distance deviation and angle deviation between the actual entry point target and the theoretical entry point target.

[0005] However, not all surgical navigation systems are equipped with optical measurement devices. For systems that do not include optical measurement devices, the spatial position of the needle tip cannot be directly measured, so the above method cannot be used to test the system accuracy. This limits the scope of application of such surgical navigation systems and brings difficulties to their accuracy evaluation. Summary of the invention

[0006] In view of this, in order to at least partially solve the above technical problems, the present invention discloses a surgical navigation equipment accuracy testing system, which aims to break through the limitations of optical measurement equipment and provide a surgical navigation equipment accuracy testing method based on laser tracking.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] In one aspect, the present invention provides a surgical navigation device accuracy testing system, the system comprising:

[0009] Precision testing tooling, image scanning equipment, laser tracker and robotic arm, wherein the precision testing tooling and the end of the robotic arm are provided with a target ball matching the laser tracker;

[0010] Measurement methods include:

[0011] Get the transformation matrix from the scanned image coordinate system to the robot arm coordinate system;

[0012] Controlling the movement of the robot arm according to the transformation matrix based on the starting point and the end point on the scanned image;

[0013] The starting and ending coordinates of the robot arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robot arm, and the coordinates of the starting and ending points in the precision test tooling actually measured by the laser tracker are combined to obtain the equipment accuracy.

[0014] Preferably, obtaining a transformation matrix from a scanning image coordinate system to a robotic arm coordinate system includes:

[0015] Determine a first transformation relationship from a scanning image coordinate system to a laser tracker coordinate system based on a reference point on the precision test fixture;

[0016] Determine a second conversion relationship between the laser scanner coordinate system and the robotic arm coordinate system based on a test point at the end of the robotic arm;

[0017] And a conversion relationship from the scanning image coordinate system to the robot arm coordinate system is obtained according to the first conversion relationship and the second conversion relationship.

[0018] Preferably, determining a first conversion relationship from a scanning image coordinate system to a laser tracker coordinate system based on a reference point on the precision test fixture includes:

[0019] Determine the first coordinate of the reference point on the precision test fixture;

[0020] Scanning the reference point using an image scanning device to obtain a second coordinate of the reference point in the scanned image;

[0021] Use a laser tracker to measure the reference point on the precision test fixture to obtain the third coordinate of the reference point;

[0022] The first conversion relationship is determined according to the first coordinate and the second coordinate, and the first coordinate and the third coordinate in sequence.

[0023] Preferably, determining a second conversion relationship between the laser scanner coordinate system and the robotic arm coordinate system based on the robotic arm end test point includes:

[0024] Determine the coordinates of the test point in the robot arm coordinate system, and simultaneously measure the test point in the laser tracker coordinate system using a laser tracker;

[0025] A second conversion relationship is obtained according to the coordinates of the test point in the robot arm coordinate system and the coordinates of the test point in the laser tracker coordinate system.

[0026] Preferably, the starting point and end point coordinates actually reached by the robotic arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robotic arm, including:

[0027] Construct a target ball coordinate system based on the target ball at the end of the robotic arm, and determine the coordinates of the actual starting point and end point in the target ball coordinate system;

[0028] The conversion matrix from the target sphere coordinate system to the laser tracker coordinate system is obtained, and the coordinates of the actual starting point and end point in the laser tracker coordinate system are obtained according to the conversion matrix.

[0029] Preferably, a target sphere coordinate system is constructed based on the target sphere at the end of the manipulator, including:

[0030] S1. There are three target balls at the end of the robotic arm, with defined coordinates as R1 (x1, y1, z1), R2 (x2, y2, z2), and R3 (x3, y3, z3);

[0031] S2, taking the target ball R2 as the origin of the coordinate system, we get:

[0032] x-axis direction vector for:

[0033] ;

[0034] y-axis direction vector for:

[0035] ;

[0036] z-axis direction vector for:

[0037] ;

[0038] S3. Normalize the x, y and z axis direction vectors respectively to obtain:

[0039]

[0040] In the formula, , , are the normalized x, y and z axis direction vectors respectively.

[0041] Preferably, determining the coordinates of the starting point and the end point actually reached in the target sphere coordinate system includes:

[0042] According to the calibration positioning tool size, get the starting point in the target sphere coordinate system The coordinates are:

[0043]

[0044] in, is the starting point coordinate.

[0045] The end point in the target sphere coordinate system is obtained according to the following formula The coordinates are:

[0046]

[0047] In the formula, is the path length between the starting point and the end point in the target sphere coordinate system.

[0048] Preferably, the transformation matrix from the target sphere coordinate system to the laser tracker coordinate system is:

[0049]

[0050] In the formula, is the coordinate of the origin R2 in the laser tracker coordinate system.

[0051] Preferably, the device accuracy includes angle deviation and distance deviation;

[0052] Define the path formed by the starting point and end point coordinates actually reached by the robot arm in the laser tracker coordinate system as the first path, and the path formed by the starting point and end point coordinates actually measured by the laser tracker in the precision test fixture as the second path;

[0053] Angular deviation, which is the angle between the first path and the second path;

[0054] The distance deviation includes the distance from the starting point coordinates in the precision test fixture actually measured by the laser tracker to the first path, the distance from the end point coordinates in the precision test fixture actually measured by the laser tracker to the first path, and the Euclidean distance between the end point coordinates actually reached by the robot arm in the laser tracker coordinate system and the end point coordinates in the precision test fixture actually measured by the laser tracker.

[0055] It can be seen from the above technical solutions that the present invention discloses a surgical navigation device accuracy testing system which is universal, and not only provides the possibility of accuracy testing for surgical navigation systems without optical measurement equipment, but also because the present invention does not rely on specific optical measurement equipment, it can be implemented on more types of surgical navigation systems, thereby expanding the application scope of surgical navigation systems.

[0056] In addition, the present application can accurately obtain the transformation matrix from the scanned image coordinate system to the robotic arm coordinate system, ensuring that the surgical navigation system can be accurately mapped and positioned in actual operation;

[0057] In addition, by calculating the deviation between the actual position and the theoretical position of the target ball at the end of the robotic arm, the system accuracy of the surgical navigation device can be accurately evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0059] Figure 1 A schematic diagram of the structure of the surgical navigation equipment accuracy testing system provided by the present invention;

[0060] Figure 2 The present invention provides a method for obtaining the actual starting point of the robot arm. and end point Schematic diagram of coordinates in the target sphere coordinate system. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] Embodiment 1:

[0063] The present invention provides a surgical navigation equipment accuracy testing system, which provides a new and effective method for the field of surgical navigation equipment accuracy testing. It not only solves the problem that some systems are difficult to perform accuracy testing due to the lack of optical measurement equipment, but also improves the accuracy and convenience of the test, which is of great significance to improving the overall level of medical surgical navigation technology.

[0064] In this embodiment, the test system includes:

[0065] The precision test tool is used to provide test points for precision testing. In this embodiment, the reference points or test points on the precision test tool are made of materials with clear imaging in medical images;

[0066] Image scanning equipment, used to scan the precision test tooling to obtain a scanned image containing the test points;

[0067] A robotic arm, used to move according to target points in the scanned image;

[0068] The laser tracker is used to measure the test points on the precision test fixture and the target position of the robot arm movement, wherein the precision test fixture and the end of the robot arm are provided with a target ball matching the laser tracker.

[0069] This application uses a laser tracker measurement tool to perform system accuracy testing on a system that does not include an optical measurement device. In this embodiment, the measurement method includes:

[0070] Get the transformation matrix from the scanned image coordinate system to the robot arm coordinate system;

[0071] Controlling the movement of the robot arm according to the transformation matrix based on the starting point and the end point on the scanned image;

[0072] The starting and ending coordinates of the robot arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robot arm, and the coordinates of the starting and ending points in the precision test tooling actually measured by the laser tracker are combined to obtain the equipment accuracy.

[0073] To facilitate implementation, Figure 1 As shown, in this embodiment, a coordinate conversion unit, a robot arm driving unit, and a precision detection unit are respectively provided for the above steps.

[0074] Further, in one embodiment,

[0075] Get the transformation matrix from the scanned image coordinate system to the robot arm coordinate system, including:

[0076] (1) Determine the first transformation relationship from the scanning image coordinate system to the laser tracker coordinate system based on the reference point on the precision test fixture; including:

[0077] Determine the first coordinate of the reference point on the precision test fixture;

[0078] In this embodiment, the third-party organization establishes a coordinate system based on the measurement results given after the precision testing tool is calibrated, according to the spatial positions between the points after calibration, so as to obtain the first coordinate of the reference point on the precision testing tool in the coordinate system.

[0079] Use image scanning equipment to scan the reference point and obtain the second coordinate of the reference point in the scanned image; Note: the coordinates of the reference point can be read directly on the image.

[0080] Then, the transformation matrix from the precision test fixture to the scanned image is obtained based on the first coordinate and the second coordinate:

[0081]

[0082] Further, a laser tracker is used to measure the reference point on the test fixture to obtain the third coordinate of the reference point;

[0083] The laser tracker in the present invention is matched with corresponding software, and the reference point coordinates of the point can be directly read from the software.

[0084] Combine the first coordinate and the third coordinate and use the existing registration algorithm to determine the transformation matrix from the laser tracker to the precision test fixture coordinate system:

[0085]

[0086] Finally, the first conversion relationship from the scanned image to the laser tracker is obtained as follows:

[0087]

[0088] (2) Determine a second transformation relationship between the laser scanner coordinate system and the robotic arm coordinate system based on the test point at the end of the robotic arm;

[0089] A target ball is installed at the end of the robotic arm. When the robot is in the starting position, a laser tracker is used to test the spatial position of the test point at the end of the robotic arm based on the target ball installed at the end of the robotic arm.

[0090] Note: Three target balls can be installed at the same time. If there is only one target ball, the positions of the three target balls can be installed one by one and measured one by one.

[0091] At the same time, the coordinates of the test point in the robot arm coordinate system are determined;

[0092] This application uses the commonly used forward kinematics method to determine the coordinate values ​​of the test points in the robot arm coordinate system based on the body parameters and joint angle values ​​of the robot arm.

[0093] It is used to obtain the second transformation relationship according to the coordinates of the test point in the robot coordinate system and the coordinates in the laser tracker coordinate system, that is:

[0094]

[0095] Note: The calculation process refers to patent 202310101952.1.

[0096] (3) According to the first transformation relationship and the second transformation relationship, the transformation relationship from the scanning image coordinate system to the robot arm coordinate system is obtained:

[0097]

[0098] After obtaining the conversion between the image and the robot arm coordinate system, when a point is selected from the tooling image, the robot arm will move to the corresponding position on the precision test tooling.

[0099] In the present invention, this process can be achieved by a robot arm driving unit.

[0100] When the robotic arm reaches the specified target position, the navigation device can be accurately measured.

[0101] In one embodiment,

[0102] Accuracy measurements of surgical navigation equipment, including:

[0103] Firstly, the starting point and end point coordinates of the robot arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robot arm.

[0104] The following is an explanation through a specific embodiment. In this embodiment, the starting point selected in the scan image is A and the end point is B. When the robot arm moves to the corresponding points A and B respectively, the positions of the three target balls R1, R2, and R3 at the end of the robot are measured by a laser tracker;

[0105] Then, through the positions of the three target balls and the calibrated positioning tooling, the robot can calculate the actual needle entry point and lesion point. , .

[0106] The specific steps include:

[0107] 1) Construct the target ball coordinate system based on the three target balls at the end of the robotic arm; refer to Figure 2 In (a), the steps are:

[0108] S1. There are three target balls at the end of the robotic arm, and their positions are R1 (x1, y1, z1), R2 (x2, y2, z2), and R3 (x3, y3, z3) (measured by a laser tracker);

[0109] S2, take target ball R2 as the origin of the coordinate system, and the path of target ball R1 and target ball R2 as the x-axis direction vector:

[0110]

[0111] The path of target ball R2 and target ball R3 is a vector on the XZ plane:

[0112]

[0113] According to the vector and Multiply to get the y-axis direction vector:

[0114]

[0115] Finally, according to the vector and Multiply to get the z-axis direction vector:

[0116]

[0117] S3. Normalize the x, y and z axis direction vectors respectively to obtain:

[0118]

[0119] In the formula, , , are the normalized x, y and z axis direction vectors respectively.

[0120] Get the transformation matrix from the target sphere coordinate system to the laser tracker coordinate system:

[0121]

[0122] In the formula, is the coordinate of the origin R2 in the laser tracker coordinate system.

[0123] 2) Determine the starting point where the robot actually reaches and end point Coordinates in the target sphere coordinate system;

[0124] In this embodiment, refer to Figure 2 In (b), according to the calibrated size of the calibration positioning fixture, the position of the needle entry point relative to the target sphere coordinate system can be known, and the expression of the needle entry point in the target sphere coordinate system is obtained as:

[0125]

[0126] Because the direction of the needle entry point and the lesion point designed by the tooling is parallel to the direction from R2 to R3 of the target ball, the direction of the needle entry point and the lesion point is the z-axis direction of the target ball coordinate system. , the lesion point is expressed in the target sphere coordinate system:

[0127]

[0128] 4) And according to the transformation matrix, the coordinates of the actual starting point and end point in the laser tracker coordinate system are obtained:

[0129]

[0130] P 入针点 , P 病灶点 That is, the position of the needle entry point and the lesion point in the laser tracker coordinate system.

[0131] Furthermore, the coordinates of the starting point and the end point in the tooling are tested by combining the actual measurement accuracy of the laser tracker to obtain the equipment accuracy. In the present invention, the theoretical path is measured by the laser tracker to measure the position of the target ball at point AB on the tooling, and the position of point A and point B of the tooling , According to,A,B, , The accuracy of navigation equipment can be calculated.

[0132] In one embodiment,

[0133] Equipment accuracy includes angle deviation and distance deviation;

[0134] Define the path formed by the starting point and end point coordinates actually reached by the robot arm in the laser tracker coordinate system as the first path, and the path formed by the starting point and end point coordinates actually measured by the laser tracker in the precision test fixture as the second path;

[0135] Angular deviation, which is the angle between the first path and the second path;

[0136] The distance deviation includes the distance from the starting point coordinates in the precision test fixture actually measured by the laser tracker to the first path, the distance from the end point coordinates in the precision test fixture actually measured by the laser tracker to the first path, and the Euclidean distance between the end point coordinates actually reached by the robot arm in the laser tracker coordinate system and the end point coordinates in the precision test fixture actually measured by the laser tracker.

[0137] According to an embodiment of the present invention,

[0138] The angle deviation is:

[0139]

[0140] Points A, B and the line Distance , :

[0141]

[0142] Where:

[0143] ----Point A to straight line distance;

[0144] ----Coordinate A and coordinate The vector composed of

[0145] ----Point B to straight line distance;

[0146] ---Coordinate B and coordinate The vector composed of

[0147] Distance deviation of lesion point :

[0148]

[0149] in, The actual end point reached by the robot arm in the laser tracker coordinate system The coordinates of The coordinates of the end point B in the accuracy test fixture actually measured by the laser tracker.

[0150] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0151] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A surgical navigation equipment accuracy testing system, characterized in that: include: Precision testing tooling, image scanning equipment, laser tracker and robotic arm, wherein the precision testing tooling and the end of the robotic arm are provided with a target ball matching the laser tracker; Measurement methods include: Get the transformation matrix from the scanned image coordinate system to the robot arm coordinate system; Controlling the movement of the robot arm according to the transformation matrix based on the starting point and the end point on the scanned image; The starting and ending coordinates of the robot arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robot arm, and the coordinates of the starting and ending points in the precision test tooling actually measured by the laser tracker are combined to obtain the equipment accuracy.

2. The accuracy testing system according to claim 1, characterized in that: Get the transformation matrix from the scanned image coordinate system to the robot arm coordinate system, including: Determine a first transformation relationship from a scanning image coordinate system to a laser tracker coordinate system based on a reference point on the precision test fixture; Determine a second conversion relationship between the laser scanner coordinate system and the robotic arm coordinate system based on a test point at the end of the robotic arm; And a conversion relationship from the scanning image coordinate system to the robot arm coordinate system is obtained according to the first conversion relationship and the second conversion relationship.

3. The accuracy testing system according to claim 2, characterized in that: Determine the first transformation relationship from the scanning image coordinate system to the laser tracker coordinate system based on the reference point on the precision test fixture, including: Determine the first coordinate of the reference point on the precision test fixture; Scanning the reference point using an image scanning device to obtain a second coordinate of the reference point in the scanned image; Use a laser tracker to measure the reference point on the precision test fixture to obtain the third coordinate of the reference point; The first conversion relationship is determined according to the first coordinate and the second coordinate, and the first coordinate and the third coordinate in sequence.

4. The accuracy testing system according to claim 2, characterized in that: Determining a second transformation relationship between the laser scanner coordinate system and the robotic arm coordinate system based on the robotic arm end test point includes: Determine the coordinates of the test point in the robot arm coordinate system, and simultaneously measure the test point in the laser tracker coordinate system using a laser tracker; A second conversion relationship is obtained according to the coordinates of the test point in the robot arm coordinate system and the coordinates of the test point in the laser tracker coordinate system.

5. The accuracy testing system according to claim 1, characterized in that: The actual starting and ending coordinates of the robot arm in the laser tracker coordinate system are calculated based on the target ball at the end of the robot arm, including: Construct a target ball coordinate system based on the target ball at the end of the robotic arm, and determine the coordinates of the actual starting point and end point in the target ball coordinate system; The conversion matrix from the target sphere coordinate system to the laser tracker coordinate system is obtained, and the coordinates of the actual starting point and end point in the laser tracker coordinate system are obtained according to the conversion matrix from the target sphere coordinate system to the laser tracker coordinate system.

6. The accuracy testing system according to claim 5, characterized in that: The target ball coordinate system is constructed based on the target ball at the end of the robotic arm, including: S1. There are three target balls at the end of the robotic arm, with defined coordinates as R1 (x1, y1, z1), R2 (x2, y2, z2), and R3 (x3, y3, z3); S2, taking the target ball R2 as the origin of the coordinate system, we get: x-axis direction vector for: ； y-axis direction vector for: ； z-axis direction vector for: ； S3. Normalize the x, y and z axis direction vectors respectively to obtain: ； In the formula, , , are the normalized x, y and z axis direction vectors respectively.

7. The accuracy testing system according to claim 5, characterized in that: Determine the coordinates of the actual starting point and end point in the target sphere coordinate system, including: According to the calibration positioning tool size, get the starting point in the target sphere coordinate system The coordinates are: ； in, is the starting point coordinate; The end point in the target sphere coordinate system is obtained according to the following formula The coordinates are: ； In the formula, is the path length between the starting point and the end point in the target sphere coordinate system.

8. The accuracy testing system according to claim 5, characterized in that: The transformation matrix from the target sphere coordinate system to the laser tracker coordinate system is: ； In the formula, is the coordinate of the origin R2 in the laser tracker coordinate system.

9. The accuracy testing system according to claim 1, characterized in that: Equipment accuracy includes angle deviation and distance deviation; Define the path formed by the starting point and end point coordinates actually reached by the robot arm in the laser tracker coordinate system as the first path, and the path formed by the starting point and end point coordinates actually measured by the laser tracker in the precision test fixture as the second path; Angular deviation, which is the angle between the first path and the second path; The distance deviation includes the distance from the starting point coordinates in the precision test fixture actually measured by the laser tracker to the first path, the distance from the end point coordinates in the precision test fixture actually measured by the laser tracker to the first path, and the Euclidean distance between the end point coordinates actually reached by the robot arm in the laser tracker coordinate system and the end point coordinates in the precision test fixture actually measured by the laser tracker.

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