An axial calibration block and calibration method for an optical navigation positioning system

Abstract

The application relates to the technical field of medical treatment and discloses an axial calibration block for an optical navigation positioning system and a calibration method. The axial calibration block for the optical navigation positioning system comprises a calibration block, wherein a plurality of front-end hole positions with consistent hole depths are arranged on one side of the calibration block and are used for inserting front ends of surgical instruments; the number of the front-end hole positions is 10, and the front-end hole positions are numbered as No. 1-10; the diameters of the front-end hole positions from No. 1 to No. 10 are sequentially reduced; a sharp-end calibration hole is arranged on the calibration block and is used for placing a sharp-end point of a surgical instrument; and a plurality of infrared reflective balls are assembled on the calibration block and are used for positioning of an optical positioning system. The axial calibration block for the optical navigation positioning system and the calibration method provided by the application solve the problem that the cognitive axial direction of a surgical instrument with different axial directions of a front end and a clamping end does not conform to the actual axial direction, and the surgical navigation sense of a doctor is avoided from being affected.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to an axial calibration block and a calibration method for an optical navigation and positioning system. Background Art

[0002] During the use of optical navigation, in addition to using standard tools provided by the manufacturer, there is often a need to track the position and axial direction of the tips of different surgical instruments.

[0003] Currently, most navigation and tracking methods for surgical instruments on the market track only the tip, assuming its axis is aligned with the axis specified by the universal optical navigation tool holder (hereinafter referred to as the universal adapter). This method works well for coaxial surgical instruments (such as some endoscopes), but for surgical instruments with different axes between the tip and the clamping end (such as bone forceps used in orthopedic surgery), there is a discrepancy between the perceived axis and the actual axis, which affects the surgeon's experience of surgical navigation.

[0004] Therefore, it is necessary to provide an axial calibration block and calibration method for an optical navigation and positioning system to solve the above technical problems. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides an axial calibration block and a calibration method for an optical navigation and positioning system.

[0006] The axial calibration block for the optical navigation and positioning system provided by the present invention includes a calibration block, wherein: one side of the calibration block is provided with multiple front end holes with consistent hole depth, which are used to insert the front end of the surgical instrument; the calibration block is provided with a tip calibration hole for placing the tip point of the surgical instrument; the calibration block is equipped with multiple infrared reflective balls for positioning the optical positioning system.

[0007] Preferably, there are 10 front end holes, numbered 1-10, and the diameters of the front end holes No. 1-10 decrease sequentially.

[0008] Preferably, there are four infrared reflective balls, numbered A, B, C, and D, which are respectively located at the four corners of the calibration block.

[0009] The present invention proposes an axial calibration method for an optical navigation and positioning system, including the axial calibration block for the optical navigation and positioning system as described above. The calibration method includes the following steps:

[0010] S1. Obtain calibration block and universal adapter parameters through configuration files;

[0011] S2. Obtain the calibration block and universal adapter rotation matrix through the optical positioner

[0012] S3. Clamp the universal adapter to the end of the surgical instrument to be tracked and fix it, and insert the front end of the surgical instrument into the appropriate front end hole of the calibration block until it contacts the bottom plane of the hole;

[0013] S4. Rotating the axial vector of the universal adapter to the axial direction of the surgical instrument through a rotation calibration algorithm;

[0014] S5. Place the tip of the surgical instrument in the tip calibration hole to perform tip calibration, thereby completing the calibration process for the surgical instrument.

[0015] Preferably, the rotation calibration algorithm comprises the following steps:

[0016] P1, obtain the quaternions Q0, Q between the calibration block coordinate system, the optical positioner coordinate system and the universal adapter coordinate system through the optical positioning system. x , Q y , Q z , and the offset vector τ(t x ,t y ,t z );

[0017] P2. Calculate the corresponding rotation matrix and homogeneous matrix:

[0018] Rotation Matrix

[0019]

[0020] Homogeneous matrix

[0021] P3. Assume that the axial vector of the surgical instrument tip in the surgical instrument tip coordinate system is The tip coordinate is t0; the axial vector of the calibration hole position i in the calibration block coordinate system is (determined by the engineering drawing of the calibration block), the coordinates of the center point at the bottom of the hole are t1(x1,y1,z1);

[0022] P4. Based on the above two axial vectors and coordinate points, calculate the rotation matrix from the surgical instrument tip coordinate system to the calibration block coordinate system according to the rotation transformation The value of

[0023] P5. The rotation matrix from the calibration block to the surgical instrument to be calibrated is obtained by calculation, thereby completing the axial calibration of the surgical instrument to be calibrated.

[0024] Compared with related technologies, the axial calibration block and calibration method for an optical navigation and positioning system provided by the present invention have the following beneficial effects:

[0025] The axial calibration block and calibration method of the present invention can accurately calibrate the axial direction of the surgical instrument, avoiding the error caused by the discrepancy between the perceived axial direction and the actual axial direction in traditional methods, thereby improving the accuracy of surgical navigation.

[0026] Since the calibrated axis of the surgical instrument is consistent with the actual one, the doctor can more intuitively understand the position and direction of the surgical instrument during the operation, thereby improving the physical perception of surgical navigation;

[0027] The calibration method of the present invention is not only applicable to coaxial surgical instruments, but also to surgical instruments with different axial directions between the front end and the clamping end (such as bone forceps used in orthopedic surgery), and has broad application prospects.

[0028] The calibration method of the present invention is relatively simple to operate. It only requires inserting the surgical instrument into the appropriate hole of the calibration block and completing the calibration through the rotation calibration algorithm. It is easy to promote and use in clinical practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic structural diagram of an axial calibration block for an optical navigation and positioning system provided by the present invention;

[0030] Figure 2 A flowchart of an axial calibration method for an optical navigation and positioning system provided by the present invention;

[0031] Figure 3 A schematic diagram of coordinate system transformation in an axial calibration method for an optical navigation and positioning system provided by the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] The present invention provides an axial calibration block for an optical navigation and positioning system, comprising a calibration block (such as Figure 1 As shown), wherein: a plurality of front end holes with the same hole depth are provided on one side of the calibration block for inserting the front end of the surgical instrument, and the number of the front end holes is 10, numbered 1-10, and the diameters of the front end holes No. 1-10 decrease successively; a tip calibration hole is provided on the calibration block for placing the tip point of the surgical instrument; the calibration block is equipped with a plurality of infrared reflective balls for positioning the optical positioning system, and the number of the infrared reflective balls is 4, numbered A, B, C, and D, which are respectively located at the four corners of the calibration block.

[0034] The present invention proposes an axial calibration method for an optical navigation and positioning system (such as Figure 2 As shown), including the axial calibration block for the optical navigation and positioning system as described above, the calibration method includes the following steps:

[0035] S1. Obtain calibration block and universal adapter parameters through configuration files;

[0036] S2. Obtain the calibration block and universal adapter rotation matrix through the optical positioner

[0037] S3. Clamp the universal adapter to the end of the surgical instrument to be tracked and fix it, and insert the front end of the surgical instrument into the appropriate front end hole of the calibration block until it contacts the bottom plane of the hole;

[0038] S4. Rotating the axial vector of the universal adapter to the axial direction of the surgical instrument through a rotation calibration algorithm;

[0039] S5. Place the tip of the surgical instrument in the tip calibration hole to perform tip calibration, thereby completing the calibration process for the surgical instrument.

[0040] The rotation calibration algorithm includes the following steps:

[0041] P1, obtain the quaternions Q0, Q between the calibration block coordinate system, the optical positioner coordinate system and the universal adapter coordinate system through the optical positioning system. x , Q y , Q z , and the offset vector τ(t x ,t y ,t z );

[0042] P2. Calculate the corresponding rotation matrix and homogeneous matrix:

[0043] Rotation Matrix

[0044]

[0045] Homogeneous matrix

[0046] P3. Assume that the axial vector of the surgical instrument tip in the surgical instrument tip coordinate system is The tip coordinate is t0; the axial vector of the calibration hole position i in the calibration block coordinate system is (determined by the engineering drawing of the calibration block), the coordinates of the center point at the bottom of the hole are t1(x1,y1,z1);

[0047] P4. Based on the above two axial vectors and coordinate points, calculate the rotation matrix from the surgical instrument tip coordinate system to the calibration block coordinate system according to the rotation transformation The value of

[0048] P5. The rotation matrix from the calibration block to the surgical instrument to be calibrated is obtained by calculation, thereby completing the axial calibration of the surgical instrument to be calibrated, namely:

[0049] because in is the rotation matrix from the calibration block to the surgical instrument to be calibrated, is the rotation matrix from the universal adapter to the surgical instrument to be calibrated, is the rotation matrix from the world coordinate system (navigation device) to the universal adapter, is the rotation matrix from the calibration block to the world coordinate system, so we can get

[0050] Then its rotation matrix

[0051]

[0052] All of these can be obtained through the configuration files of the optical locator, calibration device, and universal adapter, and will not be described in detail here.

[0053] The above steps complete the axial calibration of the surgical instrument to be calibrated.

[0054] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An axial calibration method for an optical navigation and positioning system, characterized in that: The invention comprises an axial calibration block for an optical navigation and positioning system, and the calibration method comprises the following steps: S1. Obtain the calibration block and universal adapter parameters from the configuration file. One side of the calibration block is provided with multiple front-end holes of uniform depth for inserting the front end of a surgical instrument. The calibration block is provided with a tip calibration hole for accommodating the tip of the surgical instrument. The calibration block is equipped with multiple infrared reflective balls for positioning by the optical positioning system. There are 10 front-end holes, numbered 1-10, with the diameters of the front-end holes decreasing in sequence. There are four infrared reflective balls, numbered A, B, C, and D, located at the four corners of the calibration block, respectively. S2. Obtain the calibration block and universal adapter rotation matrix through the optical positioner S3. Clamp the universal adapter to the end of the surgical instrument to be tracked and fix it, and insert the front end of the surgical instrument into the appropriate front end hole of the calibration block until it contacts the bottom plane of the hole; S4. Rotating the axial vector of the universal adapter to the axial direction of the surgical instrument through a rotation calibration algorithm; S5. Place the tip of the surgical instrument in the tip calibration hole to perform tip calibration, completing the calibration process for the surgical instrument; The rotation calibration algorithm includes the following steps: P1, obtain the quaternions Q0, Q between the calibration block coordinate system, the optical positioner coordinate system and the universal adapter coordinate system through the optical positioning system. x , Q y , Q z , and the offset vector τ(t x , t y , t z ); P2. Calculate the corresponding rotation matrix and homogeneous matrix: Rotation Matrix ， Homogeneous matrix , P3. Assume that the axial vector of the surgical instrument tip in the surgical instrument tip coordinate system is , the tip coordinate is t0; the axial vector of the calibration hole position i in the calibration block coordinate system is , the coordinates of the center point of the bottom of the hole are t1(x1, y1, z1); P4. Based on the above two axial vectors and coordinate points, calculate the rotation matrix from the surgical instrument tip coordinate system to the calibration block coordinate system according to the rotation transformation The value of P5. The rotation matrix from the calibration block to the surgical instrument to be calibrated is obtained by calculation, thereby completing the axial calibration of the surgical instrument to be calibrated, namely: because ,in is the rotation matrix from the calibration block to the surgical instrument to be calibrated, is the rotation matrix from the universal adapter to the surgical instrument to be calibrated, is the rotation matrix from the world coordinate system to the universal adapter, is the rotation matrix from the calibration block to the world coordinate system, so we can get ; Then its rotation matrix , = .

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