A method for overall kinematic spatial positioning of a surgical robot

Abstract

This invention proposes a method for overall kinematic spatial positioning of a surgical robot, comprising the following steps: Step 1, constructing the kinematics from the base to the end effector of the front robotic arm; Step 2, constructing the kinematics from the initial position of the end-effector arm (i.e., the end effector of the front robotic arm) to the fixed point; Step 3, constructing the spatial point mapping from the fixed point to the end effector arm; Step 4, constructing the overall kinematics from the base to the end effector arm. This method for overall kinematic spatial positioning of a surgical robot can solve the alignment and positioning problem between existing medical instruments and the operating table, enabling the endoscope lens to observe the lesion area from the optimal angle and optimal positioning distance along the desired posture. This ensures that the surgeon can perform safe and efficient surgical manipulation of the lesion area under the support of the lens's motion spatial positioning angle field.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a method for overall kinematic spatial positioning of a surgical robot. Background Technology

[0002] Currently, precision intelligent surgical systems such as surgical robots and intraoperative medical imaging equipment are weak links in my country's medical equipment industry. With the expanding indications for robot-assisted surgery and increased clinical acceptance of emerging technologies, the surgical robot market is entering a phase of rapid development. Among high-end medical equipment, surgical robots are widely recognized both domestically and internationally as the future trend of surgery, possessing enormous development potential.

[0003] However, most existing minimally invasive medical devices often require a lot of time and effort to adjust their position during preoperative setup. The assembly process requires repeated positioning in order to ensure that the surgical robot and the surgical table are in the most ideal position and that the surgical operation can be performed in the best collaborative space. Summary of the Invention

[0004] To address the problems existing in the prior art, this application proposes a method for overall kinematic spatial positioning of surgical robots, which solves the problem of alignment and positioning between existing medical devices and the operating table. This allows the endoscope lens to observe the lesion area from the optimal angle and optimal positioning distance along the desired posture, ensuring that the surgeon can perform safe and efficient surgical manipulation of the lesion area with the support of the lens's motion spatial positioning angle field.

[0005] To achieve the above objectives, this application proposes a method for overall kinematic spatial positioning of a surgical robot. The surgical robot includes a base, a central column mounted on the base, a first rotating structure mounted on the central column, a boom connected to the first rotating structure, a second rotating structure connected to the boom, a passive positioning device connected to the second rotating structure, and an endoscope-holding arm connected to the end of the passive positioning device. The endoscope-holding arm includes a first joint connected to the end of the passive positioning device, a second joint connected to the first joint, a parallelogram joint connected to the second joint, and a telescopic link connected to the parallelogram joint. The position near the end of the telescopic link is designated as a fixed point, which is a position with a fixed distance constraint from the passive positioning device. The end position of the telescopic link is designated as the end of the endoscope-holding arm, and an endoscope is connected to this position via a lens connecting rod. The base, central column, first rotating structure, boom, second rotating structure, and passive positioning device are designated as the front-end robotic arm, and the end position of the front-end robotic arm refers to the end of the passive positioning device. The method includes the following steps:

[0006] Step 1: Construct the kinematics from the base to the end effector of the front robotic arm;

[0007] Step 2: Construct the initial position of the lens-holding arm, that is, the kinematics from the end of the front robotic arm to the fixed point;

[0008] Step 3: Construct a spatial point mapping from the fixed point to the end of the lens holder;

[0009] Step 4: Construct the overall kinematics from the base to the end of the lens-holding arm.

[0010] In some embodiments, step 1 utilizes the DH method to model and analyze the front-end robotic arm, calculates the spatial transformation and positional transfer relationships between each joint and the end effector, and obtains the end-effector output information of the surgical robot's front-end robotic arm; specifically, step 1 includes the following steps:

[0011] Step 101: Describe the pose of the rigid body using the homogeneous transformation method;

[0012] Step 102: Input the initial parameter values ​​of the front-end robotic arm and construct a coordinate system from the base to the end of the front-end robotic arm;

[0013] Step 103: Construct the DH parameter table for the front-end robotic arm;

[0014] Step 104: Establish the kinematics of the base and the end effector of the front robotic arm.

[0015] In some embodiments, step 104 includes the following steps:

[0016] Step 1041: Combining the DH parameter table of the front-end robotic arm constructed in step 103, the general formula for solving the kinematics of the base and the end effector of the front-end robotic arm is obtained.

[0017] Step 1042: Calculate the end position and normal direction from the base to the front end of the surgical robot's robotic arm.

[0018] In some embodiments, the lens-holding arm includes four characteristic movement modes, namely:

[0019] Pitch motion: Rotating the controlled angle of the second joint of the endoscope arm allows adjustment of the pitch angle of the lens, enabling doctors to observe the lesion area;

[0020] Yaw motion: The controlled angle of the parallelogram joint of the rotating arm can be adjusted to change the yaw angle of the lens, allowing doctors to observe the lesion area.

[0021] Rotation motion: Adjust the lens connection rod mounted at the end of the lens holding arm to rotate the angle along the direction of the lens connection rod, so that the doctor can adjust the field of view angle;

[0022] Feeding motion: Adjust the retraction distance of the lens connecting rod in the feeding direction. When the preset length is extended or retracted along the lens connecting rod, and the field of view angle is set, the doctor can observe the lesion at the optimal distance and position by controlling the arm holding the endoscope during the operation.

[0023] In some embodiments, step 2 includes the following steps:

[0024] Step 201: Construct a coordinate system with fixed fixed points;

[0025] Step 202: Construct the DH parameter table with fixed fixed points;

[0026] Step 203: Construct the initial position of the lens-holding arm, that is, the mapping relationship from the end of the front robotic arm to the fixed point.

[0027] In some embodiments, in step 3, the spatial point mapping of the lens end is calculated using a spatial projection method, taking into account the spatial geometric constraints of the endoscope lens structure; the size of the lens connecting rod and the range of motion of the rotation joint are adjusted; and the spatial motion range of the lens end posture is calculated so that the field of view of the endoscope lens covers the collaborative workspace at the end of the endoscope arm.

[0028] In some embodiments, in step 4, a base coordinate system is constructed with the center of the base as the origin; under the unified base coordinate system, an overall kinematic model of the posture from the base to the end of the lens-holding arm is established.

[0029] The beneficial effect of the solution in this application is that the above-mentioned overall kinematic spatial positioning method of the surgical robot can solve the problem of alignment and positioning between existing medical devices and the operating table, so that the endoscope lens can observe the lesion area from the best angle and the best positioning distance along the desired posture, thereby ensuring that the doctor can perform safe and efficient surgical manipulation of the lesion area under the support of the lens motion spatial positioning angle field. Attached Figure Description

[0030] Figure 1 A schematic diagram of the structure of a surgical robot in the prior art is shown.

[0031] Figure 2 A diagram of the kinematic joint space coordinate system of the front-end robotic arm in the embodiment is shown.

[0032] Figure 3 A diagram of the joint coordinate system of the fixed-point parallelogram mechanism in the embodiment is shown.

[0033] Figure 4 A diagram showing the mapping relationship of the endoscope's field of view on the endoscope arm in an embodiment is provided.

[0034] Figure 5The diagram shows the motion workspace of the endoscope arm under the endoscopic field of view, in mm.

[0035] Reference numerals: 1-base, 2-central column, 3-first rotating structure, 4-suspending rod, 5-second rotating structure, 6-passive positioning device, 61-center of the starting end of the passive positioning device, 62-center of the ending end of the passive positioning device, 7-eyepiece holding arm, 71-first joint, 72-second joint, 73-parallelogram joint, 74-telescopic link, 75-fixed point, 76-end of the eyepiece holding arm. Detailed Implementation

[0036] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0037] In the description of this application, it should be understood that the terms "first," "second," etc., are used to distinguish similar objects, rather than to describe or indicate a specific order or sequence. The terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0038] Currently, surgical robots are characterized by multiple joints and modular features. For example... Figure 1 As shown, the surgical robot includes:

[0039] Base 1: Includes surgical platform device for positioning and transportation, patient surgical platform electronics and connector panel;

[0040] Central column 2: The central column 2 moves the hanger 4 up or down;

[0041] Hanging rod 4: Hanging rod 4 is an adjustable rotating support structure for the lens holding arm 7;

[0042] First rotating structure 3 and second rotating structure 5: wherein the first rotating structure 3 is connected between the central column 2 and the hanger 4, and the second rotating structure 5 is connected between the hanger 4 and the passive positioning device 6;

[0043] Passive positioning device 6: During preoperative positioning, the fixed point 75 at the end of the traction arm is positioned to the puncture point feature area.

[0044] The endoscope arm 7 includes a first joint 71 connected to the end of the passive positioning device, a second joint 72 connected to the first joint 71, a parallelogram joint 73 connected to the second joint 72, and a telescopic link 74 connected to the parallelogram joint 73. The position near the end of the telescopic link 74 is designated as a fixed point 75, which is a position with a fixed distance constraint from the passive positioning device 6. The end position of the telescopic link 74 is designated as the end of the endoscope arm 76, at which an endoscope is connected via a lens connecting rod.

[0045] Specifically, the base 1, central column 2, first rotating structure 3, hanging rod 4, second rotating structure 5 and passive positioning device 6 are referred to as the front-end robotic arm, and the end position of the front-end robotic arm refers to the end of the passive positioning device 6.

[0046] The description of the four characteristic movement modes of the lens-holding arm 7 involved in this application is as follows: Figure 2 As shown:

[0047] 1) Pitch motion: The controlled angle of the second joint 72 of the rotating arm 7. The adjustable tilt angle of the lens allows doctors to observe the lesion area;

[0048] 2) Yaw motion: The controlled angle of the parallelogram joint 73 of the rotating arm 7. The adjustable yaw angle at the lens end allows doctors to observe the lesion area;

[0049] 3) Rotation motion: Adjust the lens connecting rod mounted at the end 76 of the lens holding arm, and rotate it by an angle ψ along the direction of the lens connecting rod. z This makes it easier for doctors to adjust the angle of their field of vision;

[0050] 4) Feed motion: Adjust the retraction distance of the lens connecting rod in the feed direction. If the length S along the lens connecting rod direction is extended or retracted... dist With the field of view angle set, the doctor can accurately position and observe the lesion at the optimal distance by manipulating the arm holding the endoscope during the operation.

[0051] Once the preoperative positioning of the surgical robot is completed (positioning from the base 1 to the end of the front robotic arm), the intraoperative control of the endoscope arm 7 is a reproduction of the autonomous control of the endoscope arm based on the above four motion modes.

[0052] In view of the structure of the surgical robot described above, this application proposes a method for overall kinematic spatial localization of the surgical robot. This method employs the DH method to study the kinematic mapping relationships of each joint of the robotic arm, and calculates the spatial transformation and position transfer relationships between each joint and the end effector. The process of modeling the robotic arm's kinematics using the DH method is described below:

[0053] (1) Input initial values ​​and construct a coordinate system;

[0054] (2) Establish the DH parameter table;

[0055] (3) Establish the kinematic mapping relationship between the beginning and the end;

[0056] (4) Establish positive kinematics and output the end position and direction.

[0057] The overall kinematic space positioning method for surgical robots involved in this application includes the following steps:

[0058] Step 1: Construct the kinematics from base 1 to the end of the front robotic arm.

[0059] Step 2: Construct the kinematics from the initial position of the lens-holding arm 7 (i.e. the end of the front robotic arm) to the fixed point 75.

[0060] Step 3: Construct a spatial point mapping from fixed point 75 to the end of the lens arm 76.

[0061] Step 4: Construct the overall kinematics from base 1 to the end of the lens arm 76.

[0062] Specifically, in step 1, (1) the forward kinematics of the surgical robot's front end arm (i.e., from the base 1 to the end of the front end arm) is established using the DH parameter method.

[0063] (2) Adjust the size of the movable links and the range of motion of the joints of the front robotic arm;

[0064] (3) Calculate the position of the end of the front robotic arm to complete the preoperative adjustment of the front robotic arm.

[0065] The core idea of ​​step 1 is as follows: use the DH method to model and analyze the front-end robotic arm, calculate the spatial transformation and position transfer relationship between each joint and the end effector, and obtain the end-effector output information of the surgical robot's front-end robotic arm.

[0066] The specific process of step 1 is as follows:

[0067] Step 101: Use the homogeneous transformation method to describe the pose of the rigid body.

[0068] Using the homogeneous transformation method to describe the pose of a rigid body allows the kinematic relationships between links to be transformed into mathematical calculations. In a Cartesian coordinate system {A}, the position vector of any point P in space is described by a 3×1 vector. A P is:

[0069]

[0070] In the formula: P xThis represents the x-component of point P along the x-axis; P y This represents the component of point P along the y-axis; P z This represents the component of point P along the z-axis. A In P, A represents the coordinate system {A}.

[0071] To represent the orientation of any rigid body B in three-dimensional space, a coordinate system {B} is established, corresponding to the unit direction vector x. B y B z B The relationship with coordinate system {A} is as follows:

[0072]

[0073] In the formula: In this context, A represents coordinate system {A}, and B represents coordinate system {B}.

[0074] because A x B , A y B , A z B Both are unit vectors and are perpendicular to each other, {r ij} represents the column element corresponding to the unit vector, i,j=1,2,3, such as A x B Corresponding to {r i1 The column vector of} A y B Corresponding to {r i2 The column vector of} A z B Corresponding to {r i3 The column vectors of}, so for the rotation matrix There is a relation:

[0075]

[0076] in, T is the transpose of the matrix, and · represents the determinant.

[0077] use This indicates the position of the origin of coordinate system {B} within coordinate system {A}. Let {B} represent the orientation of the coordinate axes in coordinate system {A}. Then:

[0078]

[0079] in, Indicates the position of an object. Indicates the posture of an object.

[0080] The general formula for representing rigid body pose using homogeneous matrices is:

[0081]

[0082] Step 102: Input the initial parameter values ​​of the front-end robotic arm and construct a coordinate system from the base 1 to the end of the front-end robotic arm.

[0083] DH parametric coordinate system construction criteria: such as Figure 2 As shown, a base coordinate system is constructed with the center of the bottom end of base 1 as the origin.

[0084] (1) The z-axis is vertically upward, and the first coordinate system is determined by translating it by a distance d1 along the z-axis;

[0085] (2) Rotate counterclockwise around the z-axis by an angle θ2, then rotate clockwise by 90° to determine the second coordinate system;

[0086] (3) Rotate the x-axis clockwise by 90° and translate the z-axis by a distance d3 to determine the third coordinate system;

[0087] (4) Rotate counterclockwise around the x-axis by 90°, then rotate counterclockwise around the z-axis by θ4, then rotate counterclockwise around the z-axis by 90° to determine the fourth coordinate system;

[0088] (5) Rotate 90° clockwise around the z-axis and then translate a distance d5 along the negative z-axis to determine the fifth coordinate system;

[0089] (6) Rotate 90° clockwise around the x-axis, then rotate 90° clockwise around the z-axis, and then translate d6 along the z-axis to determine the 6th coordinate system.

[0090] Step 103: Construct the DH parameter table for the front-end robotic arm.

[0091] Table 1. DH Parameter Table for the Front-End Robotic Arm

[0092] Serial Number <![CDATA[α i-1 ]]> <![CDATA[a i-1 ]]> <![CDATA[θ i ]]> <![CDATA[d i ]]> 1 0 0 0 <![CDATA[d1]]> 2 0 0 <![CDATA[θ2-90°]]> 0 3 -90° 0 0 <![CDATA[d3]]> 4 90° 0 <![CDATA[θ4+90°]]> 0 5 0 0 -90° <![CDATA[-d5]]> 6 -90° 0 -90° <![CDATA[d6]]>

[0093] Where, for any link i, a i Indicates the use of link length (from z) i-1 To z i Along x i (axis offset distance), α i Indicates the linkage rotation angle (around x). i By z i-1 Go to z i (angle of rotation of the axis), d i Indicates the offset distance of the link (from x) i-1 To x i Along z i-1 (distance between axes), θ i Indicates the joint angle of the link (around z). iBy x i-1 Go to x i (The rotation angle of the shaft), combined with the actual measured values, determine the DH parameters in Table 1, and set d1∈[1950,2681], d3∈[850,1269], d5∈[0,466], d6∈[0,403], θ2∈[0,117.6°], θ4∈[0,341.9°].

[0094] Step 104: Establish the kinematics of base 1 and end effector of the front robotic arm.

[0095] Specifically, step 104 includes the following steps:

[0096] Step 1041: Combining the DH parameter table of the front-end robotic arm constructed in step 103, the general formula for solving the kinematics of the base 1 and the end effector of the front-end robotic arm is obtained.

[0097] Under the DH transformation concept, if the transformation of adjacent links can be expressed relative to coordinate system {i-1}, then the transformation matrix represented by coordinate system {i} is... Then the general formula for link transformation is:

[0098]

[0099] Among them, T z,d Relative to parameter d i Transformation, T z,θ Represents relative to parameter θ i Transformation, T x,a Relative to parameter a i Transformation, T x,α Represents relative to parameter α i The transformation.

[0100] Based on the DH parameter table, the transition matrices for each connected joint are obtained:

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107] The mathematical expression of the homogeneous transformation matrix from base 1 to the end effector of the robotic arm is:

[0108]

[0109] Where, s² = sin(θ²), c² = cos(θ²), s 24 =sin(θ2+θ4), c 24 =cos(θ2+θ4),

[0110] n represents the normal vector, n = o × a;

[0111] o represents the orientation vector, which is the direction of the line connecting the end effector of the surgical robot's forearm and the axis of the first joint 71.

[0112] 'a' represents the proximity vector, which is the direction of the line connecting the end-effector normal direction of the surgical robot's fore-end robotic arm and the end-effector normal direction of the first joint 71.

[0113] p represents the position vector, relative to the origin of the base coordinate system, and the position of the end effector of the surgical robot's forearm.

[0114] Determine the position of the end effector of the robotic arm:

[0115]

[0116] Furthermore, since the normal direction of the end effector of the surgical robot's forearm can be expressed as n = o × a, we can further obtain:

[0117]

[0118]

[0119]

[0120] Here, det(·) represents the determinant of the matrix. express The matrix formed by the intersection of the elements in rows 2 and 3 and columns 2 and 3. express The matrix formed by the intersection of the elements in rows 1 and 3 and columns 1 and 3. express The matrix formed by the intersection of the first and second rows and the first and second columns.

[0121] Determine the normal direction of the end effector of the robotic arm:

[0122]

[0123] Step 1042: Calculate the end position and normal direction from the base 1 to the front end of the surgical robot's robotic arm.

[0124] To obtain the end position and normal direction of the surgical robot's forearm from base 1, after the aforementioned DH transformation, it is necessary to rotate the robot clockwise around the y-axis by an angle α.s =45°, then translate T along the origin of the coordinate system. s0 The 7th coordinate system is determined by units; where T s0 Based on actual measurements:

[0125]

[0126] in, R y This represents a rotation of θ around the y-axis.

[0127] T Rc =Rot(-45,y), (9-2)

[0128] Among them, T Rc This indicates a rotation of -45 degrees around the y-axis.

[0129] Combining (8-1) to (9-2), the end effector kinematic equations from base 1 to the front end of the robotic arm are:

[0130]

[0131] Using the kinematics (10) of the front-end robotic arm, the position from the base 1 to the end of the front-end robotic arm is calculated as follows:

[0132]

[0133] The normal direction from base 1 to the end effector of the robotic arm is calculated as follows:

[0134]

[0135] In step 2, (1) the kinematic mapping relationship dependent on the fixed point position is established using the DH parameter method;

[0136] (2) Adjust the size of the movable link and the range of motion of the joint of the lens-holding arm 7;

[0137] (3) Calculate the spatial position of the fixed point to complete the pitch and yaw motion of the fixed point.

[0138] The specific process of step 2 is as follows:

[0139] Step 201: Construct a coordinate system with fixed fixed points.

[0140] During intraoperative manipulation, since the distal end of the surgical robot's robotic arm has a relatively fixed positional relationship with the fixed point (RCM), it is reasonable to establish a coordinate system centered on the RCM. For example... Figure 3 As shown, the DH parametric coordinate system construction criterion is: utilizing the fixed point position transformation relationship, in Figure 3Under the action of two rotary joints 1 and 2, the surgical robot's endoscope arm rotates around the RCM. This means that the DH parameter coordinate system is established with the RCM as the origin, establishing coordinate systems 1 and 2; the origin of coordinate system 3 is at the end joint of the endoscope arm.

[0141] Step 202: Construct the DH parameter table with fixed fixed points.

[0142] a) Rotate counterclockwise around the z-axis by an angle Establish the first coordinate system;

[0143] b) Rotate 90° clockwise around the x-axis and 90° counterclockwise around the z-axis. Then rotate clockwise around the z-axis by an angle α r The second coordinate system was determined;

[0144] c) Rotate counterclockwise 90° around the x-axis, then translate along the z-axis by a distance d3 to determine the third coordinate system.

[0145] Table 2 Kinematic DH Parameters for Fixed Points

[0146]

[0147] The mathematical expression for the homogeneous transformation matrix from the end effector of the robotic arm to the fixed coordinate system is:

[0148]

[0149] The kinematic equations of the fixed point relative to the end effector of the robotic arm are derived as follows:

[0150]

[0151] Where, α r =28°,

[0152] n represents the normal vector, n = o × a;

[0153] o represents the azimuth vector, the direction of the line connecting the fixed point and the axis of the lens connecting rod;

[0154] 'a' represents the approximation vector, the direction of the line connecting the fixed point and the normal direction at the end of the lens arm;

[0155] p represents the position vector, and the fixed point is relative to the origin of the base coordinate system.

[0156] Step 203: Construct the mapping relationship between the initial position of the lens-holding arm 7 and the fixed point.

[0157] Based on the kinematic principle of a fixed point, the motion mapping from the end of the front robotic arm (i.e., the initial position of the lens-holding arm 7) to the fixed point is as follows:

[0158]

[0159] The direction of the fixed-point method is determined as follows:

[0160]

[0161] In step 3, (1) the spatial point mapping at the end of the lens is calculated by combining the spatial geometric constraints of the endoscope lens structure with the spatial projection method.

[0162] (2) Adjust the size of the lens connecting rod and the range of motion of the rotation joint;

[0163] (3) Calculate the spatial movement range of the lens end posture so that the field of view of the endoscope lens accurately covers the collaborative work space (enveloping the lesion area) at the end of the endoscope arm, so as to complete the rotation and feeding movement of the endoscope lens field of view.

[0164] Specifically, in step 3, from Figure 4 It can be seen that ∠PDH I =60° is based on the given angle ∠PAH B =30° is obtained from the property of a spatial dihedral angle. Based on the parameters of the lens arm, ∠PH p H I =45°, then the position of the field of view of the arm holding the glasses determines the angle of view of H. p Coordinate positioning. A simple calculation method can be provided based on the actual situation, simply by calculating the vector... distance H can then be further calculated using the DH method. p The location.

[0165] H I The spatial projection of the center point of the mirror, i.e., the orthocenter. The axis of the graphic arm is RCM, and the triangle △APH p It is a mirror. The value is between 20 and 80 mm. Therefore, in the right triangle Rt△PDH... I middle,

[0166]

[0167] In right triangle Rt△PH I H p middle,

[0168]

[0169] Substituting (16) into equation (17-1), we can calculate...

[0170]

[0171] Considering the mapping relationship of the endoscopic field of view of the lens, a new field of view mapping distance is derived:

[0172]

[0173] in,

[0174] Therefore, in equation (14), the value of d3 is changed, that is, the lens is translated along the axis of the end of the lens holder by d. 3,new Replacing d3, the position of the lens's field of view at the end of the lens-holding arm relative to the end of the front robotic arm is obtained:

[0175]

[0176] In step 4, (1) a base coordinate system is constructed with the center of the base as the origin;

[0177] (2) Under a unified base coordinate system, an overall kinematic model can be established from the base 1 to the end posture of the lens arm.

[0178] Specifically, in step 4, after the above kinematic transformations, combined with equations (11) and (19), the position of the lens field of view at the end of the arm relative to the base is obtained as follows:

[0179]

[0180] The direction of the lens field of view at the end of the lens arm is determined as follows:

[0181]

[0182] Finally, by solving the entire forward kinematics from base 1 to end of lens arm 76, the position and orientation of end of lens arm are calculated.

[0183] This application, based on the modular structural design of the surgical robot, enables the decoupling of its overall kinematics solution. Within the DH parameter framework, firstly, a Cartesian coordinate system is constructed to establish the forward kinematics of the front-end robotic arm. The dimensions of its movable links and the range of motion of its joints are adjusted to determine the end-effector position, completing the preoperative adjustment of the front-end robotic arm. Secondly, during intraoperative manipulation, using the end-effector position as a reference point, a kinematic spatial point mapping relationship dependent on the fixed-point position is established. The dimensions of the movable links and the range of motion of the endoscope-holding arm are adjusted to calculate the spatial position of the fixed point, enabling pitch and yaw motions. Thirdly, a spatial point mapping from the fixed point to the end-effector position is constructed. Finally, combining the above solutions, the entire kinematic solution process from the base to the end-effector position is calculated, such as... Figure 5 As shown.

[0184] The overall kinematic spatial positioning method for surgical robots involved in this application can calculate the overall kinematics of the endoscope arm through steps 1 to 4, thereby obtaining the working space of the endoscope lens's field of view. Therefore, the method involved in this invention effectively solves the alignment and positioning problem between existing medical devices and the operating table to a certain extent. This method enables the endoscope lens to observe the lesion area at the optimal angle and optimal positioning distance along the desired posture, so as to ensure that the doctor can perform safe and efficient surgical manipulation of the lesion area under the support of the lens motion spatial positioning angle field.

[0185] This invention focuses on the precise localization technology of surgical robots for lesion areas, proposing a method for overall kinematic spatial localization of the surgical robot. This method allows for arbitrary extension of the robot's configuration when sending operational commands containing key joint parameters, ensuring that the end of the end-effector—the lens—extending along the fixed point direction can observe the lesion area from the optimal viewing angle and distance, thus "commanding" the related instrument arms to complete the surgical procedure. The overall kinematic spatial localization method for the surgical robot involved in this invention not only utilizes modular design to decouple the solution of the overall kinematics of the surgical robot, but also uses the DH method and spatial point mapping relationship to calculate the fixed point pose and the end-effector pose, achieving precise localization and observation of the optimal viewing angle and distance for intraoperative manipulation, which is beneficial for surgeons to complete operations efficiently. The DH method and spatial point mapping localization method involved in this invention are widely used in high-tech fields such as medical robots, industrial robots, and space robots, contributing to the improvement of my country's research and development and manufacturing capabilities of high-end medical equipment and promoting the continuous development of medical-related scientific research and applications in my country.

[0186] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and concept of this application, should be included within the scope of protection of this application.

Claims

1. A method for overall kinematic spatial positioning of a surgical robot, wherein the surgical robot includes a base, a central column disposed on the base, a first rotating structure disposed on the central column, a boom connected to the first rotating structure, a second rotating structure connected to the boom, a passive positioning device connected to the second rotating structure, and an endoscope-holding arm connected to the end of the passive positioning device. The endoscope-holding arm includes a first joint connected to the end of the passive positioning device, a second joint connected to the first joint, a parallelogram joint connected to the second joint, and a telescopic link connected to the parallelogram joint. A fixed point is designated near the end of the telescopic link, which is a position with a fixed distance constraint from the passive positioning device. The end of the telescopic link is designated as the end of the endoscope-holding arm, and an endoscope is connected to this position via a lens connecting rod. The base, central column, first rotating structure, boom, second rotating structure, and passive positioning device are designated as the front-end robotic arm, and the end position of the front-end robotic arm refers to the end of the passive positioning device. The method is characterized in that: The method includes the following steps: Step 1: Construct the kinematics from the base to the end effector of the front robotic arm; Step 2: Construct the initial position of the lens-holding arm, that is, the kinematics from the end of the front robotic arm to the fixed point; Step 3: Construct a spatial point mapping from the fixed point to the end of the lens holder; Step 4: Construct the overall kinematics from the base to the end of the lens-holding arm; In step 1, the DH method is used to model and analyze the front-end robotic arm, calculate the spatial transformation and position transfer relationships between each joint and the end effector, and obtain the end-effector output information of the surgical robot's front-end robotic arm. Specifically, step 1 includes the following steps: Step 101: Describe the pose of the rigid body using the homogeneous transformation method; Step 102: Input the initial parameter values ​​of the front-end robotic arm and construct a coordinate system from the base to the end of the front-end robotic arm; Step 103: Construct the DH parameter table for the front-end robotic arm; Step 104: Establish the kinematics of the base and the end effector of the front robotic arm; Step 104 includes the following steps: Step 1041: Combining the DH parameter table of the front-end robotic arm constructed in step 103, the general formula for solving the kinematics of the base and the end effector of the front-end robotic arm is obtained. Step 1042: Calculate the end position and normal direction from the base to the front end of the surgical robot's robotic arm; Step 2 includes the following steps: Step 201: Construct a coordinate system with fixed fixed points; Step 202: Construct the DH parameter table with fixed fixed points; Step 203: Construct the initial position of the lens-holding arm, i.e., the mapping relationship from the end of the front robotic arm to the fixed point; In step 3, the spatial point mapping of the endoscope lens is calculated using the spatial projection method, taking into account the spatial geometric constraints of the endoscope lens structure; the size of the lens connecting rod and the range of motion of the rotation joint are adjusted; and the spatial motion range of the endoscope lens posture is calculated so that the field of view of the endoscope lens covers the collaborative workspace of the endoscope arm.

2. The overall kinematic spatial positioning method for a surgical robot according to claim 1, characterized in that: The lens-holding arm includes four characteristic movement modes, namely: Pitch motion: Rotating the controlled angle of the second joint of the endoscope arm allows adjustment of the pitch angle of the lens, enabling doctors to observe the lesion area; Yaw motion: The controlled angle of the parallelogram joint of the rotating arm can be adjusted to change the yaw angle of the lens, allowing doctors to observe the lesion area. Rotation motion: Adjust the lens connection rod mounted at the end of the lens holding arm to rotate the angle along the direction of the lens connection rod, so that the doctor can adjust the field of view angle; Feeding motion: Adjust the retraction distance of the lens connecting rod in the feeding direction. When the preset length is extended or retracted along the lens connecting rod, and the field of view angle is set, the doctor can observe the lesion at the optimal distance and position by controlling the arm holding the endoscope during the operation.

3. The overall kinematic spatial positioning method for a surgical robot according to claim 2, characterized in that: In step 4, a base coordinate system is constructed with the center of the base as the origin; under the unified base coordinate system, an overall kinematic model of the posture from the base to the end of the lens arm is established.

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