Real-time correction method, system and surgical robot for end tool pose

Abstract

The embodiment of the application discloses a kind of real-time correction method, system and surgical robot of end tool pose, which comprises: the pose of active follow-up area and the pose of end tool are recorded when detecting record signal;When detecting pose following signal, the corresponding relationship between the latest recorded pose of active follow-up area and the pose of end tool is used as the initial pose corresponding relationship between end tool and corresponding active follow-up area;The initial pose offset corresponding to the initial pose corresponding relationship between end tool and corresponding active follow-up area is obtained;When detecting that the pose of active follow-up area changes, the object pose offset of active follow-up area is obtained;According to initial pose offset and object pose offset, end tool is controlled to move, and the pose corresponding relationship of end tool and active follow-up area is restored to initial pose corresponding relationship.The problem that end tool pose exists lower pose adjustment accuracy when being manually adjusted is solved.

Description

[0001] This application is a divisional application of the invention patent application with application number 202110778767.7, the original application of which was filed on July 9, 2021, and the invention is entitled Real-time Correction Method, System and Surgical Robot for End-Edge Tool Pose. Technical Field

[0002] This invention relates to the field of medical devices, and more particularly to a method, system, and surgical robot for real-time correction of the pose of an end-effector. Background Technology

[0003] The purpose of total hip replacement surgery is to replace the diseased hip joint with a joint prosthesis. The surgery requires that the installation position of the prosthesis be as precise as possible, such as the installation position, abduction angle, and anteversion angle of the joint prosthesis (i.e., acetabular cup). Of course, the actual situation also needs to be determined according to the patient's physiological structure, which is usually determined by the preoperative planning.

[0004] In actual hip replacement surgery, to accurately place the acetabular cup into the acetabular fossa, the central axis of the acetabular cup must be aligned with the central axis of the acetabular fossa during the placement process. However, during the placement procedure, the acetabular cup and acetabular fossa interact, causing the acetabular fossa to change position due to the cup's action, thus preventing it from aligning with the cup's central axis. Therefore, to ensure accuracy, the acetabular cup needs to be repositioned after each placement procedure to realign its central axis with the acetabular fossa's central axis.

[0005] Therefore, in the existing technology, doctors can only rely on clinical experience to manually adjust the position of the end effector to cope with changes in the position of the hip joint. The position adjustment efficiency is low, and the low position adjustment efficiency prolongs the entire operation time of hip replacement surgery. Summary of the Invention

[0006] This invention provides a method, system, and surgical robot for real-time correction of end-effector pose, which solves the problem in the prior art that doctors can only rely on clinical experience to manually adjust the pose of the end-effector to cope with changes in hip joint pose.

[0007] In a first aspect, embodiments of the present invention provide a method for real-time correction of the pose of an end-effector, comprising:

[0008] Obtain the initial pose offset corresponding to the initial pose correspondence between the end effector and the corresponding active follower area;

[0009] When a change in the pose of the active follower region is detected, the object pose offset of the active follower region is obtained, wherein the object pose offset is the pose offset of the current pose of the active follower region relative to the initial object pose of the active follower region in the initial pose correspondence relationship.

[0010] The end effector is controlled to move according to the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence.

[0011] Secondly, embodiments of the present invention also provide a surgical robot, comprising:

[0012] The first pose acquisition device is disposed on the target object and maintains a fixed correspondence with the active follower area of ​​the target object, and is used to acquire the pose of the active follower area;

[0013] A second pose acquisition device is mounted on a robotic arm used to carry the end effector and move it, and is used to acquire the pose of the end effector.

[0014] The controller is configured to acquire the initial pose correspondence between the end effector and the corresponding active follower region; when a change in the pose of the active follower region is detected, acquire the object pose offset of the active follower region; and control the movement of the end effector based on the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower region is restored to the initial pose correspondence, wherein the object pose offset is the pose offset of the current pose of the active follower region relative to the initial object pose of the active follower region in the initial pose correspondence.

[0015] Thirdly, embodiments of the present invention also provide a real-time end-effector pose correction system, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the computer program to perform the real-time end-effector pose correction method described in any embodiment.

[0016] This invention provides a technical solution for real-time correction of end-effector pose. Compared to existing technologies, this method obtains the initial pose offset corresponding to the initial pose correspondence between the end-effector and the corresponding active follower region. When a change in the pose of the active follower region is detected, the object pose offset of the active follower region is obtained. The end-effector movement is controlled based on the initial pose offset and the object pose offset to restore the pose correspondence between the end-effector and the active follower region to the initial pose correspondence. Since the pose adjustment amount of the end-effector can be determined based on the object pose offset and the initial pose offset, controlling the end-effector movement based on this pose adjustment amount allows the end-effector to complete the following movement at the end of the movement, at which point its pose correspondence with the active follower region is restored to the initial pose correspondence. This helps improve the efficiency and accuracy of end-effector pose adjustment, thereby improving the efficiency and success rate of joint replacement surgery. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a real-time correction method for end-effector pose provided in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of a surgical robot provided in one embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of an active follower region provided in one embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram illustrating the relationship between a robotic arm and an end effector according to an embodiment of the present invention;

[0022] Figure 5 This is a structural block diagram of a surgical robot provided in another embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of a surgical robot provided in another embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0025] Figure 1 This is a flowchart illustrating a real-time end-effector pose correction method according to an embodiment of the present invention. The technical solution of this embodiment is applicable to situations where a surgical robot is controlled to correct the end-effector pose in real time based on changes in the hip joint pose, thereby restoring the pose correspondence between the end-effector and the acetabulum to its initial pose correspondence. This method can be executed by the controller of the surgical robot provided in this embodiment of the invention, which can be implemented in software and / or hardware.

[0026] like Figure 2 The diagram shown illustrates a surgical robot according to an embodiment of the present invention. The surgical robot includes a first optical array 11 disposed at the hip joint of the target object 01, a second optical array 12 disposed at a robotic arm 2 for moving an end effector 4, a third optical array 13 disposed at a base 3 for fixing the robotic arm 2, and a controller connecting the first optical array 11, the second optical array 12, and the third optical array 13. The end effector of the robotic arm 2 is used to mount the end effector, and the robotic arm 2 can carry the end effector and move under the control of the controller. The controller can be disposed inside the robot's main structure or can be a processor independent of the robot's main structure, such as a processor, server, or computer device separately disposed outside the robot's main structure.

[0027] The method specifically includes the following steps:

[0028] S101. Obtain the initial pose offset corresponding to the initial pose correspondence between the end effector and the corresponding active follower area.

[0029] The range of the active follow-up zone can be preset by the user according to specific circumstances and / or personal habits. For example, the active follow-up zone 02 can include only... Figure 3 The cone-shaped virtual region 021 in the text can also include... Figure 3 The cone-shaped virtual region 021 and the cylindrical region 022 within the preset range above it, at this time Figure 3The cylindrical region 022 above the dotted line in the diagram can correspond to the skin portion of the surgical object. The posture of the active follower region changes with the pose of the corresponding target surgical area. This embodiment uses the hip joint as an example to illustrate the technical solution. When the target surgical area is the hip joint, Figure 3 The apex of the cone-shaped virtual region coincides with the center of the acetabular fossa 023. Additionally, the active follower region can correspond to other target surgical areas, as long as it needs to maintain a fixed pose correspondence with the end effector.

[0030] The end effector is the surgical tool corresponding to the target surgical area. If the target surgical area is the hip joint, then the end effector is an acetabular cup or acetabular reamer.

[0031] The initial pose correspondence is the pose correspondence between the end effector and the corresponding active follower area that needs to be maintained in this embodiment of the invention, such as the two having their central axes coincide.

[0032] In this embodiment, if the end effector is an acetabular cup, the central axis of the end effector in the initial pose correspondence is preferably coincided with the central axis of the active follower area; if the end effector is an acetabular file, the central axis of the end effector in the initial pose correspondence can coincide with the central axis of the active follower area, or it can be set according to actual needs.

[0033] The method for determining the initial pose correspondence when the end effector is an acetabular cup includes: the controller generates a recording signal when it detects that the central axis of the active follower area coincides with the central axis of the end effector, and records the pose of the active follower area and the pose of the end effector according to the recording signal; when a pose following signal is detected, the latest recorded correspondence between the pose of the active follower area and the pose of the end effector is used as the initial pose correspondence between the end effector and the corresponding active follower area.

[0034] The method for determining the initial pose correspondence when the end effector is an acetabular reamer includes: upon detecting a recording signal, recording the pose of the active follower region and the pose of the end effector, wherein the recording signal is input by the user; upon detecting a pose following signal, using the newly recorded pose of the active follower region and the pose of the end effector as the initial pose correspondence between the end effector and the corresponding active follower region. It is understood that the user can input at least two recording signals at different times until the desired pose correspondence is obtained, and then input a pose following signal. The controller uses the pose correspondence corresponding to the last recorded signal, i.e., the user's desired pose correspondence, as the initial pose correspondence based on this pose following signal. Alternatively, the user can input at least two recording signals at different times, mark the pose correspondence corresponding to one of the recorded signals as the desired pose correspondence, and then input a pose following signal. The controller uses this desired pose correspondence as the initial pose correspondence based on this pose following signal.

[0035] For example, before the cupping procedure in hip replacement surgery, the acetabular cup (end-effector) typically needs to be moved to a preset cupping position in the active follower area. At this preset position, the central axis of the acetabular cup coincides with the central axis of the active follower area. The central axis of the acetabular cup may also have overlapped with the active follower area before reaching the preset position. The controller continuously monitors the pose correspondence between the acetabular cup and the acetabular fossa during the movement of the acetabular cup to the preset position. When the controller detects that the central axis of the acetabular cup coincides with the central axis of the acetabular fossa, it generates a recording signal and automatically records the pose of the active follower area and the end-effector based on this signal. Furthermore, when the controller detects a pose following signal input by the surgeon via a foot pedal, it uses the latest recorded pose of the active follower area and the end-effector as the initial object pose and the initial tool pose, respectively, and the correspondence between these initial object poses and initial tool poses is used as the initial pose correspondence.

[0036] For example, before the cupping procedure in hip replacement surgery, the acetabular fossa needs to be ground down using an acetabular reamer (end-effector tool). Before using the acetabular reamer to grind down the acetabular fossa, the acetabular reamer needs to be dragged into the active follow-up zone 02, for example... Figure 3The cylindrical region 022 is then used; the pose of the acetabular reamer is adjusted to achieve the desired pose correspondence between the acetabular reamer and the acetabular fossa. Preparations for acetabular bone grinding are then performed, such as preparing surgical instruments. To prevent changes in the pose correspondence between the acetabular reamer and the acetabular fossa due to changes in the patient's hip joint pose during this preparation, a user input recording signal is used. When the controller detects this recording signal, it acquires the poses of the acetabular reamer and the acetabular fossa based on the signal, using the acetabular reamer pose as the initial tool pose, the acetabular fossa pose as the initial object pose, and the correspondence between the initial tool pose and the initial corresponding pose as the initial pose correspondence. The user inputs the recording signal by stepping on the robot's foot pedals.

[0037] The initial object pose of the active follower region 02 is acquired by a first pose acquisition device, such as a first optical array 11, located on the target object (patient's hip). The initial tool pose of the end effector 4 is acquired by a second pose acquisition device, such as a second optical array 12, located on the robotic arm 2 used to move the end effector 4. It is understood that the first optical array 11 maintains a fixed pose correspondence with the active follower region 02, and the second optical array 12 maintains a fixed pose correspondence with the robotic arm 2.

[0038] After obtaining the initial object pose and initial tool pose corresponding to the initial pose, the initial pose offset is determined according to the following formula:

[0039] object T tool =Inverse( s T maker1_static )× s T maker2_static

[0040] Among them, Inverse ( s T maker1_static )for s T maker1_static The inverse matrix, s T maker1_static The initial object pose for the active follower region. s T maker2_static This represents the initial tool pose of the end effector. object T tool This is the initial pose offset, which can be understood as the pose offset of the initial tool pose relative to the initial object pose. In practical use, the pose offset of the initial object pose relative to the initial tool pose can also be used as the initial pose offset.

[0041] S102. When a change in the pose of the active follower region is detected, the object pose offset of the active follower region is obtained, wherein the object pose offset is the pose offset of the current pose of the active follower region relative to the initial object pose of the active follower region in the initial pose correspondence.

[0042] When the controller detects a pose following signal and simultaneously detects a change in the current pose of the active follower region compared to the initial object pose, it acquires the current pose of the active follower region 02 through the first optical array 11. In this embodiment, the pose correction frequency of the end effector is greater than or equal to 250 times / s, and correspondingly, the frequency at which the first optical array acquires the current pose of the active follower region is also greater than or equal to 250 times / s.

[0043] The object pose offset of the active follower region relative to its initial object pose is determined by the following formula:

[0044] maker1_static T maker1_dynamic =Inverse( s T maker1_static )× s T maker1_dynamic

[0045] Among them, Inverse ( s T maker1_static )for s T maker1_static The inverse matrix; s T maker1_static The initial object pose for the active follower region. s T maker1_dynamic The current pose of the active follower region. maker1_static T maker1_dynamic This is the object's pose offset.

[0046] S103. Control the movement of the end-effector based on the initial pose offset and the object pose offset, so that the pose correspondence between the end-effector and the active follower area is restored to the initial pose correspondence.

[0047] Once the initial pose offset corresponding to the initial pose correspondence and the object pose offset of the current pose of the active follower area relative to its initial object pose are determined, the pose adjustment amount required to adjust the end effector to the target pose is determined based on these initial pose offsets and object pose offsets. The target pose is the pose of the end effector when it completes the current pose following operation.

[0048] The formula for calculating the pose adjustment amount is as follows:

[0049] tool_static T tool_dynamic =Inverse( objectT tool )× maker1_static T maker1_dynamic × object T tool

[0050] Among them, Inverse ( object T tool )for object T tool The inverse matrix, tool_static T tool_dynamic This is the pose adjustment amount for the end effector.

[0051] It is understandable that the pose adjustment amount corresponds to the motion amount of the end effector, and the motion of the end effector is driven by the robotic arm. Therefore, the controller drives the motion of the end effector by controlling the motion of the robotic arm. To this end, this embodiment transforms the pose adjustment amount to the reference coordinate system based on the transformation relationship between the coordinate system corresponding to the end effector and the reference coordinate system. This determines the pose change amount of the robotic arm used to carry the end effector in the reference coordinate system, and controls the robotic arm to drive the end effector to move according to the pose change amount. This ensures that when the robotic arm completes the motion of the pose change amount, the end effector completes the motion of the pose adjustment amount, and the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence.

[0052] The reference coordinate system corresponds to the third optical array 13, which is set on the base 3 for connecting the robotic arm 2.

[0053] The coordinate system corresponding to the end effector is the same as the coordinate system corresponding to the second optical array. The transformation relationship between this coordinate system and the reference coordinate system can be calculated from the forward kinematics of each joint position of the robotic arm.

[0054] The formula for calculating the change in pose of the robotic arm in the reference coordinate system is as follows:

[0055] B T tool_dynamic = B T Tool_static × Tool_static T tool_dynamic

[0056] in, B T Tool_static This represents the transformation matrix between the coordinate system corresponding to the end effector and the reference coordinate system when the end effector and the active follower region are in their initial pose correspondence. B T tool_dynamic This represents the change in pose of the robotic arm in the reference coordinate system. In fact, including B T tool andtool T marker2 The former refers to the actual control input of the robotic arm, while the latter defines the kinematic correspondence between the robotic arm and the end effector. Since there are multiple ways for the robotic arm to drive the end effector, this kinematic correspondence is needed to uniquely define this movement. This allows for the determination of the end effector's movement by defining the robotic arm's movement, enabling arbitrary pose adjustments to the end effector driven by the robotic arm. It should be noted that this kinematic correspondence needs to be calibrated in advance, and correspondingly, the kinematic correspondence between the base and the robotic arm also needs to be calibrated in advance.

[0057] In some embodiments, the controller outputs a pose follow-up completion signal when it detects that the end-effector has completed a pose adjustment. This pose follow-up completion signal can be output through a flashing light mounted on the robotic arm or through a display device connected to the controller. This embodiment does not limit the specific form of the pose follow-up completion signal.

[0058] In some embodiments, when the controller detects a follow stop signal, it stops detecting and obtains the current pose of the active follow area. At this time, the active follow area becomes a free area, and the pose correspondence between the end tool and the active follow area can be any pose correspondence.

[0059] Exemplary working process: See Figure 4 , Figure 5 and Figure 6 Before the cupping procedure in hip replacement surgery, the end effector (acetabular cup) needs to be moved to the preset cupping location and its pose locked. At this point, the central axis of the acetabular cup at the preset cupping location coincides with the central axis of the active follower area (or acetabular fossa). When the controller detects that the central axis of the acetabular cup coincides with the central axis of the active follower area, it automatically records the pose of the end effector through the second optical array 12 and the pose of the active follower area through the first optical array 11, and uses the pose correspondence between the recorded end effector pose and the active follower area pose as the initial pose correspondence. The surgeon taps... Figure 3The acetabular cup striking handle 42 above the central link 41 performs a striking operation on the acetabular cup. After being struck, the acetabular cup collides with the acetabular fossa, causing a change in the acetabular fossa's pose. Due to this change in acetabular fossa pose, the pose relationship between the end effector and the active follower area is no longer the initial pose correspondence. If the striking operation continues under these conditions, surgical failure is likely. At this point, the surgeon can input a pose-following signal via a preset foot pedal. When the controller detects the pose-following signal, it executes steps S101-S103, thereby adjusting the end effector's pose in a timely manner when the acetabular fossa pose changes. After the end effector's pose adjustment is complete, it automatically performs a pose-locking operation and outputs a prompt signal indicating that pose-following is complete. Understandably, the central axis of the adjusted end effector coincides with the central axis of the acetabular fossa, and the surgeon performs the striking operation again based on this prompt signal. Understandably, after each cupping operation, the acetabular cup collides with the inner wall of the acetabular fossa. This collision changes the pose correspondence between the acetabular cup and the active follower area (acetabular fossa). The controller will perform a pose follow operation when it detects this change. To improve the accuracy of the cupping operation, the user must wait until the controller has completed the pose follow operation before performing the next cupping operation, until the acetabular cup is fully inserted into the acetabular fossa. Understandably, the central axis of the linkage coincides with the central axis of the end effector 4, see [link to documentation]. Figure 4 .

[0060] Another exemplary procedure: When the end effector is an acetabular reamer, the surgeon needs to drag the end effector to... Figure 3The cylindrical region 022 above the dashed line is adjusted to correspond with the pose of the active follower region 02. Preparations for acetabular bone reshaping are then made, such as preparing surgical instruments. To prevent changes in the pose correspondence between the acetabular reamer and the acetabular fossa due to changes in the patient's hip joint pose during preparation, the doctor inputs a recording signal via the first pedal press. This signal allows the controller to acquire the pose of the end effector and the active follower region. Then, a pose following signal is input via the second pedal press. The controller uses this signal to determine the current poses of the acetabular reamer and the acetabular fossa as the initial tool pose and the initial object pose, respectively, and the pose correspondence between them as the initial pose correspondence. The controller also determines the initial pose offset of the initial tool pose relative to the initial object pose. When a change in the pose of the hip joint relative to its initial object pose is detected, the object pose offset of the current pose of the hip joint relative to its initial object pose is obtained, and the pose adjustment amount of the end effector is determined based on the initial pose offset and the object pose offset. The end effector is then controlled to move based on the pose adjustment amount, so that when the end effector completes the movement, a prompt signal indicating that the pose following is completed is output on the display device. At this time, the pose correspondence between the end effector and the hip joint is restored to the initial pose correspondence.

[0061] The technical solution of the real-time pose correction method for end-effectors provided in this invention, compared with the prior art, obtains the initial pose offset corresponding to the initial pose correspondence between the end-effector and the corresponding active follower region; when a change in the pose of the active follower region is detected, the object pose offset of the active follower region is obtained; the end-effector movement is controlled according to the initial pose offset and the object pose offset, so that when the movement ends, the pose correspondence between the end-effector and the active follower region is restored to the initial pose correspondence; since the pose adjustment amount of the end-effector can be determined according to the object pose offset and the initial pose correspondence, and the movement of the end-effector is controlled according to the pose adjustment amount, the end-effector can complete the following movement when the movement ends, and at that time, its pose correspondence with the active follower region is restored to the initial pose correspondence, which helps to improve the efficiency and accuracy of end-effector pose adjustment, thereby improving the efficiency and success rate of joint replacement surgery.

[0062] Figure 5 This is a structural block diagram of a surgical robot provided in another embodiment of the present invention. See also... Figure 5 and Figure 6The surgical robot includes a first pose acquisition device 11, a second pose acquisition device 12, and a controller 14. The first pose acquisition device 11 is disposed on the target object 01 and maintains a fixed correspondence with the active follower area 02 of the target object 01, and is used to acquire the pose of the active follower area. The second pose acquisition device 12 is disposed on the robotic arm 2 for carrying the end effector 4 and is used to acquire the pose of the end effector 4. The controller 14 is used to acquire the initial pose offset corresponding to the initial pose correspondence between the end effector 4 and the corresponding active follower area 02. When a change in the pose of the active follower area is detected, the controller acquires the object pose offset of the active follower area 02. The controller controls the movement of the end effector according to the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence. The object pose offset is the current pose of the active follower area relative to the initial object pose of the active follower area in the initial pose correspondence.

[0063] In one embodiment, the surgical robot further includes a third pose acquisition device 13, which is disposed on a base for fixing the robotic arm and is used to provide a reference coordinate system for the movement of the robotic arm. The first pose acquisition device is a first optical array, the second pose acquisition device is a second optical array, and the third pose acquisition device is a third optical array.

[0064] The range of the active follow-up zone can be preset by the user according to specific circumstances and / or personal habits. For example, the active follow-up zone 02 can include only... Figure 3 The cone-shaped virtual region 021 in the text can also include... Figure 3 The cone-shaped virtual region 021 and the cylindrical region 022 within the preset range above it, at this time Figure 3 The cylindrical region 021 above the dotted line in the diagram corresponds to the skin portion of the surgical subject. The posture of the active follower region changes with the pose of the corresponding target surgical area. This embodiment uses the hip joint as an example to illustrate the technical solution. It should be noted that when the target surgical area is the hip joint, the apex of the cone-shaped virtual region 021 coincides with the center of the acetabulum 023. Alternatively, the active follower region can also correspond to other target surgical areas, as long as it needs to maintain a fixed pose correspondence with the end effector. The target subject is the patient receiving the corresponding surgery.

[0065] The end effector is the surgical tool corresponding to the target surgical area. If the surgical area corresponds to the hip joint, then the end effector is an acetabular cup or acetabular reamer.

[0066] The initial pose correspondence is the fixed pose correspondence between the end effector and the corresponding active follower area that needs to be maintained in this embodiment of the invention, such as the two having their central axes coincide.

[0067] In this embodiment, if the end effector is an acetabular cup, the central axis of the end effector in the initial pose correspondence is preferably coincided with the central axis of the active follower area; if the end effector is an acetabular file, the central axis of the end effector in the initial pose correspondence can coincide with the central axis of the active follower area, or it can be set according to actual needs.

[0068] The method for determining the initial pose correspondence when the end effector is an acetabular cup includes: the controller generates a recording signal when it detects that the central axis of the active follower area coincides with the central axis of the end effector, and records the pose of the active follower area and the pose of the end effector according to the recording signal; when a pose following signal is detected, the latest recorded correspondence between the pose of the active follower area and the pose of the end effector is used as the initial correspondence between the end effector and the corresponding active follower area.

[0069] The method for determining the initial pose correspondence when the end effector is an acetabular reamer includes: upon detecting a recording signal, recording the pose of the active follower region and the pose of the end effector, wherein the recording signal is input by the user; upon detecting a pose following signal, using the newly recorded pose of the active follower region and the pose of the end effector as the initial pose correspondence between the end effector and the corresponding active follower region. It is understood that the user can input at least two recording signals at different times until the desired pose correspondence is obtained, and then input a pose following signal. The controller uses the pose correspondence corresponding to the last recorded signal, i.e., the user's desired pose correspondence, as the initial pose correspondence based on this pose following signal. Alternatively, the user can input at least two recording signals at different times, mark the pose correspondence corresponding to one of the recorded signals as the desired pose correspondence, and then input a pose following signal. The controller uses this desired pose correspondence as the initial pose correspondence based on this pose following signal.

[0070] For example, before the cupping procedure in hip replacement surgery, the acetabular cup (end-effector) typically needs to be moved to a preset cupping position in the active follower area. At this preset position, the central axis of the acetabular cup coincides with the central axis of the active follower area. The central axis of the acetabular cup may also have overlapped with the active follower area before reaching the preset position. The controller continuously monitors the pose correspondence between the acetabular cup and the acetabular fossa during the movement of the acetabular cup to the preset position. When the controller detects that the central axis of the acetabular cup coincides with the central axis of the acetabular fossa, it generates a recording signal and automatically records the pose of the active follower area and the end-effector based on this signal. Furthermore, when the controller detects a pose following signal input by the surgeon via a foot pedal, it uses the latest recorded pose of the active follower area and the end-effector as the initial object pose and the initial tool pose, respectively, and the correspondence between these initial object poses and initial tool poses is used as the initial pose correspondence.

[0071] For example, before the cupping procedure in hip replacement surgery, the acetabular fossa needs to be ground down using an acetabular reamer (end-effector tool). Before using the acetabular reamer to grind down the acetabular fossa, the acetabular reamer needs to be dragged into the active follow-up zone 02, for example... Figure 3 The robot operates within a cylindrical region 022. The pose of the acetabular reamer is then adjusted to achieve the desired initial pose correspondence between the acetabular reamer and the acetabular fossa. Final preparations for acetabular bone reshaping are then performed, such as preparing surgical instruments. To prevent changes in the patient's hip joint pose during this preparation period, which could alter the pose correspondence between the acetabular reamer and the acetabular fossa, a user input recording signal is used. Upon detecting this signal, the controller acquires the poses of the acetabular reamer and the acetabular fossa based on it. The acetabular reamer's pose is used as the initial tool pose, the acetabular fossa's pose as the initial object pose, and the correspondence between the initial tool pose and the initial corresponding pose is used as the initial pose correspondence. The user inputs the recording signal by stepping on the robot's foot pedals.

[0072] The initial object pose of the active follower region 02 is obtained through a first optical array 11 set on the target object (patient's hip), and the initial tool pose of the end effector 4 is obtained through a second optical array 12 set on the robotic arm 2 used to move the end effector 4. It is understood that the first optical array 11 maintains a fixed pose correspondence with the active follower region 02, and the second optical array 12 maintains a fixed pose correspondence with the robotic arm 2.

[0073] After obtaining the initial object pose and initial tool pose corresponding to the initial pose, the initial pose offset is determined according to the following formula:

[0074] object T tool =Inverse(s T maker1_static )× s T maker2_static

[0075] Among them, Inverse ( s T maker1_static )for s T maker1_static The inverse matrix, s T maker1_static The initial object pose for the active follower region. s T maker2_static This represents the initial tool pose of the end effector. object T tool This is the initial pose offset, which can be understood as the pose offset of the initial tool pose relative to the initial object pose. In practical use, the pose offset of the initial object pose relative to the initial tool pose can also be used as the initial pose offset.

[0076] When the controller detects the pose following signal and simultaneously detects that the current pose of the active follower area has changed compared to the initial object pose, it acquires the current pose of the active follower area 02 through the first optical array 11.

[0077] The object pose offset of the active follower region relative to its initial object pose is determined by the following formula:

[0078] maker1_static T maker1_dynamic =Inverse( s T maker1_static )× s T maker1_dynamic

[0079] Among them, Inverse ( s T maker1_static )for s T maker1_static The inverse matrix, s T maker1_static The initial object pose for the active follower region. s T maker1_dynamic The current pose of the active follower region. maker1_static T maker1_dynamic This is the object's pose offset.

[0080] Once the initial pose offset corresponding to the initial pose correspondence and the object pose offset of the current pose of the active follower area relative to its initial object pose are determined, the pose adjustment amount required to adjust the end effector to the target pose is determined based on these initial pose offsets and object pose offsets. The target pose is the pose of the end effector when it completes the current pose following operation.

[0081] The formula for calculating the pose adjustment amount is as follows:

[0082] tool_static T tool_dynamic =Inverse( object T tool )× maker1_static T maker1_dynamic × object T tool

[0083] in, tool_static T tool_dynamic This is the pose adjustment amount for the end effector.

[0084] Since the pose adjustment amount of the end-effector determined based on the initial pose offset and the object pose offset is the amount of motion required for the end-effector to adjust from the initial tool pose to the target pose, controlling the movement of the end-effector based on this pose adjustment amount will restore the pose correspondence between the end-effector and the active follower area to the initial pose correspondence when the end-effector completes the pose adjustment.

[0085] It is understandable that the pose adjustment amount corresponds to the motion amount of the end effector, and the motion of the end effector is driven by the robotic arm. Therefore, the controller drives the motion of the end effector by controlling the motion of the robotic arm. To this end, this embodiment transforms the pose adjustment amount to the reference coordinate system based on the transformation relationship between the coordinate system corresponding to the end effector and the reference coordinate system. This determines the pose change amount of the robotic arm used to carry the end effector in the reference coordinate system, and controls the robotic arm to drive the end effector to move according to the pose change amount. This ensures that when the robotic arm completes the motion of the pose change amount, the end effector completes the motion of the pose adjustment amount, and the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence.

[0086] The reference coordinate system corresponds to the third optical array 13, which is set on the base 3 for connecting the robotic arm 2.

[0087] The coordinate system corresponding to the end effector is the same as the coordinate system corresponding to the second optical array. The transformation relationship between this coordinate system and the reference coordinate system can be calculated from the forward kinematics of each joint position of the robotic arm.

[0088] The formula for calculating the change in pose of the robotic arm in the reference coordinate system is as follows:

[0089] B T tool_dynamic = B T Tool_static × Tool_static T tool_dynamic

[0090] in, B T Tool_static This represents the transformation matrix between the coordinate system corresponding to the end effector and the reference coordinate system when the end effector and the active follower region are in their initial pose correspondence. B T tool_dynamic This represents the change in pose of the robotic arm in the reference coordinate system. B T tool_dynamic In fact, including B T tool and tool T marker2 The former refers to the actual control input of the robotic arm, while the latter defines the kinematic correspondence between the robotic arm and the end effector. Since there are multiple ways for the robotic arm to drive the end effector, this kinematic correspondence is needed to uniquely define this movement. This allows for the determination of the end effector's movement by defining the robotic arm's movement, enabling arbitrary pose adjustments to the end effector driven by the robotic arm. It should be noted that this kinematic correspondence needs to be calibrated in advance, and correspondingly, the kinematic correspondence between the base and the robotic arm also needs to be calibrated in advance.

[0091] In some embodiments, when the controller detects that the end-effector has completed a pose adjustment, it outputs a pose follow-up completion signal. This pose follow-up completion signal can be output through a flashing light mounted on the robotic arm or through a display device 6 connected to the controller. This embodiment does not limit the specific form of the pose follow-up completion signal.

[0092] In some embodiments, when the controller detects a follow stop signal, it stops detecting and obtains the current pose of the active follow area. At this time, the active follow area becomes a free area, and the pose correspondence between the end tool and the active follow area can be any pose correspondence.

[0093] In some embodiments, see Figure 4 , Figure 5 and Figure 6 The robotic arm 2 moves the acetabular cup or acetabular reamer via a connecting rod 41, one end of which is fitted with the acetabular cup or acetabular reamer. When the end tool is an acetabular cup, the other end of the connecting rod 41 is equipped with an acetabular cup striking handle 42. The doctor performs a cupping operation on the acetabular cup using this striking handle 42. Figure 5 It can also be seen that the central axis of the acetabular cup coincides with the central axis of the connecting rod 41.

[0094] In some embodiments, see Figure 6 As shown, the surgical robot also includes an optical camera 5, which is used to detect the positions of the first optical array 11 and the second optical array 12, thereby indirectly detecting the pose of the acetabulum and the acetabular cup.

[0095] In some embodiments, the surgical robot further includes a display device 6, which is at least used to display the current pose correspondence between the end effector and the active follower area. Preferably, the display device is also used to output information about the change between the current pose correspondence and the initial pose correspondence. For example, the current pose deviation information of the end effector relative to the initial pose correspondence, i.e., the pose adjustment amount of the end effector. Preferably, the display device 6 is also used to output a pose adjustment completion signal.

[0096] The surgical robot solution provided in this invention, compared to the prior art, involves the controller acquiring the initial pose offset corresponding to the initial pose correspondence between the end effector and the corresponding active follower area; when a change in the pose of the active follower area is detected, the controller acquires the object pose offset of the active follower area; and controls the movement of the end effector based on the initial pose offset and the object pose offset, so that when the movement ends, the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence. Since the pose adjustment amount of the end effector can be determined based on the object pose offset and the initial pose correspondence, controlling the movement of the end effector based on this pose adjustment amount allows the end effector to complete the following movement when the movement ends, at which point its pose correspondence with the active follower area is restored to the initial pose correspondence. This helps improve the efficiency and accuracy of the end effector pose adjustment, thereby improving the efficiency and success rate of joint replacement surgery.

[0097] The controller of the surgical robot provided in this embodiment of the invention can execute the real-time correction method for the end-effector pose provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0098] This invention also provides a system for automatically adjusting the acetabular cup position. The system includes a processor and a memory. The memory stores a computer program, and when the processor executes the computer program, it performs a method for real-time correction of the end-effector position. This method includes:

[0099] Obtain the initial pose offset corresponding to the initial pose correspondence between the end effector and the corresponding active follower area;

[0100] When a change in the pose of the active follower region is detected, the object pose offset of the active follower region is obtained, wherein the object pose offset is the pose offset of the current pose of the active follower region relative to the initial object pose of the active follower region in the initial pose correspondence relationship.

[0101] The end effector is controlled to move according to the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence.

[0102] Of course, the computer program of the system for automatically adjusting the acetabular cup position provided in the embodiments of the present invention is not limited to the method operation described above, and can also perform related operations in the real-time correction method for end-effector position provided in any embodiment of the present invention.

[0103] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute a real-time end-tool pose correction method as described in the various embodiments of the present invention.

[0104] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A surgical robot, characterized in that, include: A first posture acquisition device is disposed on a target object and maintains a fixed correspondence with the active follower area of ​​the target object, and is used to acquire the posture of the active follower area; The second posture acquisition device is mounted on a robotic arm used to carry the end effector and is used to acquire the posture of the end effector. The controller is configured to record the pose of the active follower region and the pose of the end effector when a recording signal is detected; when a pose following signal is detected, the controller uses the latest recorded correspondence between the pose of the active follower region and the pose of the end effector as the initial pose correspondence between the end effector and the corresponding active follower region; obtain the initial pose offset corresponding to the initial pose correspondence between the end effector and the corresponding active follower region; when a change in the pose of the active follower region is detected, the controller obtains the object pose offset of the active follower region; and control the movement of the end effector according to the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower region is restored to the initial pose correspondence.

2. The robot according to claim 1, characterized in that, The end tool is an acetabular cup or an acetabular file; When the end-effector is an acetabular cup, the recording signal is generated by the controller when it detects that the central axis of the active follower area coincides with the central axis of the end-effector; When the end tool is an acetabular file, the recording signal is input by the user.

3. The surgical robot according to claim 1, characterized in that, The controller is used to determine the pose adjustment amount of the end effector based on the initial pose offset and the object pose offset, and to control the movement of the end effector based on the pose adjustment amount.

4. The surgical robot according to claim 1, characterized in that, Also includes: The display device is at least used to display the current pose correspondence between the end effector and the active follower area.

5. The surgical robot according to claim 2, characterized in that, The end effector is the acetabular reamer, and the surgical robot also includes: Foot pedal; The controller is used to detect the pedal being stepped on and generate a recording signal or a pose following signal based on the stepping pattern.

6. The surgical robot according to any one of claims 1-5, characterized in that, The pose correction frequency of the end effector is greater than or equal to 250 times / s.

7. A real-time end-effector pose correction system, comprising a processor and a memory, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it performs the following steps: When a recording signal is detected, the pose of the active servo region and the pose of the end effector are recorded; When a pose following signal is detected, the latest recorded correspondence between the pose of the active follower region and the pose of the end effector is used as the initial pose correspondence between the end effector and the corresponding active follower region. Obtain the initial pose offset corresponding to the initial pose correspondence between the end tool and the corresponding active follower area; when a change in the pose of the active follower area is detected, obtain the object pose offset of the active follower area; The end effector is controlled to move according to the initial pose offset and the object pose offset, so that the pose correspondence between the end effector and the active follower area is restored to the initial pose correspondence.

8. The system according to claim 7, characterized in that, The step of controlling the movement of the end effector based on the initial pose offset and the object pose offset includes: The pose adjustment amount of the end effector is determined based on the initial pose offset and the object pose offset, and the movement of the end effector is controlled based on the pose adjustment amount.

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