Surgical robotic system and method of controlling the same, computer device

Abstract

The application relates to a surgical robot system and a control method thereof and a computer device. The method comprises the following steps: acquiring bone mechanical information of bone to be removed in a bone grinding area; determining friction coefficient information between the bone to be removed and an end effector of the surgical robot system based on the bone mechanical information; and determining expected contact force between the end effector and the bone to be removed in a bone grinding process based on the friction coefficient information, so that the end effector can meet an expected torque in the bone grinding process. The method can ensure that the contact force in the bone grinding process is within a control range, improves the grinding efficiency, and ensures the safety in the surgical process.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a surgical robot system and its control method, and a computer device. Background Technology

[0002] In orthopedic and neurosurgical procedures, bone resection is a crucial step in treating skull base lesions, tumor resection, or laminectomy. Traditional bone resection surgery relies on the surgeon using a hand-held drill. However, due to the complex surgical environment, such as the complex intracranial anatomy, dense distribution of nerves and functional areas, and interference from surrounding soft tissues, and because lesions often lead to abnormal bone morphology or positional variations, freehand bone resection places extremely high demands on the surgeon's spatial awareness and operational precision. During prolonged operations, fatigue or limited field of vision can easily lead to the accumulation of errors, significantly reducing both the efficiency and safety of bone resection. Summary of the Invention

[0003] Therefore, it is necessary to provide a surgical robot system and its control method and computer equipment that can improve grinding efficiency and surgical safety, in order to address the above-mentioned technical problems.

[0004] In a first aspect, this application provides a control method for a surgical robot system, comprising:

[0005] Obtain bone mechanics information of the bone to be removed in the area to be ground down;

[0006] Based on the bone mechanics information, the friction coefficient between the bone to be removed and the end effector of the surgical robot system is determined.

[0007] Based on the friction coefficient information, the desired contact force between the end effector and the bone to be removed during the bone grinding process is determined; the desired contact force is used to ensure that the end effector meets the desired torque during the bone grinding process.

[0008] In one embodiment, determining the coefficient of friction between the bone to be removed and the end effector of the surgical robot system based on the bone mechanics information includes:

[0009] A pre-set first mapping relationship is obtained, and the bone biomechanical information of the bone to be removed is obtained based on the first mapping relationship and the image grayscale information of the bone medical image. The first mapping relationship is used to characterize the correspondence between image grayscale and bone biomechanical information.

[0010] A pre-set second mapping relationship is obtained, and the friction coefficient information between the bone to be removed and the end effector is determined based on the second mapping relationship and the bone mechanics information of the bone to be removed; the second mapping relationship is used to characterize the correspondence between the friction coefficient between the end effector and the bone and the bone mechanics information.

[0011] In one embodiment, determining the desired contact force between the end effector and the bone to be removed during the bone grinding process based on the friction coefficient information includes:

[0012] Based on the desired torque corresponding to the end effector and the structural parameters of the end effector, the desired friction force of the end effector under the desired torque is obtained;

[0013] By combining the desired frictional force and the friction coefficient information, the desired contact force between the end effector and the bone to be removed during the bone grinding process is obtained.

[0014] In one embodiment, the method further includes:

[0015] A first interface and a second interface are defined in the bone-grinding region; the first interface is the upper surface of the bone-grinding region, and the second interface is located above the bone layer boundary corresponding to the bone-grinding region.

[0016] Using the first interface as the grinding start surface and the second interface as the grinding end surface, a planned grinding path corresponding to the bone area to be ground is obtained; the planned grinding path is used to indicate the movement trajectory of the end effector during the bone grinding process in the bone area to be ground.

[0017] The planned grinding path includes at least one two-dimensional curve in the two-dimensional space where each grinding layer is located, and the multiple grinding layers are distributed layer by layer along the direction from the first interface to the second interface.

[0018] In one embodiment, obtaining the planned grinding path corresponding to the bone region to be ground includes:

[0019] Determine the percutaneous fixed point corresponding to the end effector; the percutaneous fixed point is located on the skin surface and is associated with the spatial position of the area to be bone-reduced.

[0020] Using the percutaneous fixed point as the rotation reference point of the end effector, multiple concentric circle paths are obtained;

[0021] The planned grinding path is obtained based on multiple concentric circle paths; the two-dimensional curve in the planned grinding path includes multiple sub-curves, and the multiple sub-curves include the circumferential segments of the multiple concentric circle paths in the bone area to be ground.

[0022] In one embodiment, the radial spacing between the plurality of concentric circular paths is determined based on the image grayscale information of the bone medical image of the bone to be removed; wherein the radial spacing between concentric circular paths in the high grayscale region is smaller than the radial spacing between concentric circular paths in the low grayscale region, and the image grayscale value of the high grayscale region is greater than the image grayscale value of the low grayscale region.

[0023] In one embodiment, the method further includes:

[0024] The current grinding information of the end effector during the bone grinding process of the bone to be removed is obtained, and the current grinding information includes the current position, current feedback force and current speed of the end effector;

[0025] The target position information of the end effector is determined by using the expected grinding information and the current grinding information of the end effector; the expected grinding information includes the expected position of the end effector, the expected contact force corresponding to the expected position, and the preset expected speed; the expected position is determined according to the planned grinding path;

[0026] The robot arm outputs motion commands based on the target position information of the end effector, and the robot arm is used to drive the end effector to perform bone grinding operations; the motion commands are used to indicate multiple sets of joint information that the robot arm needs to move.

[0027] In one embodiment, the method further includes:

[0028] Acquire a three-dimensional image of the target object and the target pose information of the optical marker of the target object in the three-dimensional image;

[0029] The pose relationship between the optical markers of the end effector and the optical markers of the target object is acquired in real time using a vision camera.

[0030] Based on the target pose information and pose relationship of the target object, determine the end-effector pose information in the three-dimensional image of the optical marker of the end effector;

[0031] The three-dimensional model of the end effector is loaded into the three-dimensional image of the target object using the end effector pose information to determine the relative position of the end effector and the target object.

[0032] Secondly, this application also provides a surgical robot system, comprising:

[0033] robotic arm;

[0034] An end effector, connected to the end of the robotic arm, is used to perform bone grinding operations under the drive of the robotic arm;

[0035] A controller, connected to the robotic arm, includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the control method for the surgical robot system provided in the first aspect of this application.

[0036] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the control method for the surgical robot system provided in the first aspect of this application.

[0037] The aforementioned surgical robot system, its control method, and computer equipment acquire bone mechanics information of the bone to be removed in the bone-grinding area; determine the friction coefficient information between the bone to be removed and the end effector of the surgical robot system based on the bone mechanics information; and determine the desired contact force between the end effector and the bone to be removed during the bone-grinding process based on the friction coefficient information. This desired contact force is used to ensure that the end effector meets the desired torque during the bone-grinding process. Before surgery, the controller of this application determines the friction coefficient information between the end tool and the bone surface using the bone mechanics information of the bone to be removed. Combining the friction coefficient and the torque limit of the end effector, it calculates the desired contact force between the end effector and the bone surface. Through friction constraints, torque control is converted into contact force control, allowing the robotic arm to adjust the contact force between the end effector and the bone surface based on this desired contact force during the bone-grinding process. This adjustment of the contact force enables the end effector to achieve higher grinding efficiency, ensuring that the contact force during the bone-grinding process remains within a controllable range, thus improving grinding efficiency and ensuring safety during the surgery. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the surgical robot system in one embodiment;

[0040] Figure 2 This is a flowchart illustrating the control method of a surgical robot system in one embodiment;

[0041] Figure 3This is a flowchart illustrating the control method of a surgical robot system in another embodiment;

[0042] Figure 4 This is a flowchart illustrating the process of determining the desired contact force in another embodiment;

[0043] Figure 5 This is a schematic diagram of the initial bone-grinding area in one embodiment;

[0044] Figure 6 This is a schematic diagram of the initial bone-grinding area in another embodiment;

[0045] Figure 7 This is a schematic diagram of the 3D contour model of the initial bone-grinding area in one embodiment;

[0046] Figure 8 This is a schematic diagram illustrating the final determination of the bone-grinding area in one embodiment;

[0047] Figure 9 This is a schematic diagram illustrating the final determination of the bone-grinding area in another embodiment;

[0048] Figure 10 This is a schematic diagram of the first interface and the second interface in one embodiment;

[0049] Figure 11 This is a schematic diagram of the first and second interfaces in another embodiment;

[0050] Figure 12 This is a schematic diagram of the process for obtaining the planned grinding path in one embodiment;

[0051] Figure 13 This is a schematic diagram illustrating the planned grinding path in one embodiment;

[0052] Figure 14 This is a schematic diagram illustrating the planned grinding path in one embodiment;

[0053] Figure 15 This is a schematic diagram of the process for obtaining the planned grinding path in another embodiment;

[0054] Figure 16 This is a flowchart illustrating the process of determining the relative positions of the end effector and the bone-grinding region in one embodiment;

[0055] Figure 17 This is a schematic diagram of the process of outputting motion commands to a robotic arm in one embodiment;

[0056] Figure 18 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0058] In orthopedic and neurosurgical procedures, bone removal is a crucial step in treating skull base lesions, tumor resection, or laminectomy. For example, unilateral double-channel spinal endoscopy (UBE) has become an important method for treating degenerative spinal diseases. A key procedure involves the surgeon using a high-speed drill to remove bone from the posterior lamina of the spine. The extent and precision of bone removal during the procedure are highly dependent on the surgeon's experience, and the entire process is lengthy, requiring prolonged concentration and drill handling. Therefore, the entire bone removal operation can easily cause hand and mental fatigue. Furthermore, the limited operating space and interference from surrounding muscles and other soft tissues reduce the accuracy, efficiency, and safety of bone removal, increasing the risk of spinal cord and nerve root injury.

[0059] To improve grinding efficiency and surgical safety, this application provides a control method for a surgical robot system. Please refer to... Figure 1 The surgical robot system may include a robotic arm 200, an end effector 400 for connection to the end of the robotic arm 200, and a controller 100 for signal connection to the robotic arm 200. The surgical robot system may also include a sensing device 300, which is fixed to the end of the robotic arm 200 and the end effector 400 is fixedly mounted on the sensing device 300.

[0060] In one exemplary embodiment, such as Figure 2 As shown, a control method for a surgical robot system is provided, which is applied to... Figure 1 Taking controller 100 as an example, the explanation includes the following steps 202 to 206. Wherein:

[0061] Step 202: Obtain the bone mechanics information of the bone to be removed in the bone area to be ground.

[0062] The bone to be ground refers to the area of ​​bone in the target object that needs to be ground down. Bone mechanics information is used to characterize the resistance of the bone to be ground down, and it can include bone mineral density or bone hardness information, etc.

[0063] For example, before the surgery, the target area of ​​the patient is scanned using medical imaging technology such as CT or MRI to obtain three-dimensional image data of the target area. The controller selects the area of ​​bone to be removed from the target area based on the three-dimensional image data and obtains the bone density information or bone hardness information of the bone to be removed based on the three-dimensional image data.

[0064] Step 204: Determine the friction coefficient between the bone to be removed and the end effector of the surgical robot system based on bone mechanics information.

[0065] The friction coefficient information is used to reflect the interaction strength between the end effector and the bone to be removed, and it may include the friction coefficient.

[0066] For example, in the embodiments of this application, a mapping relationship between the friction coefficient between bone and end effector such as high-speed drill and bone with different bone mechanics information can be established in advance. Before the operation, the controller matches or calculates the friction coefficient between the bone to be removed and the drill based on the mapping relationship and the bone mechanics information of the bone to be removed.

[0067] Step 206: Determine the desired contact force between the end effector and the bone to be removed during the bone grinding process based on the friction coefficient information.

[0068] The desired contact force is used to ensure that the end effector meets the desired torque during the bone grinding process. The desired torque can refer to the rated torque of the end effector, or it can be determined based on the maximum output torque that the end effector can withstand without stalling.

[0069] Before surgery, the controller in this application calculates the desired contact force between the end effector and the bone surface by combining the friction coefficient and the torque limit of the end effector. This allows the robotic arm to adjust the contact force between the end effector and the bone surface based on the desired contact force during bone grinding. By adjusting the contact force, the end effector can achieve higher grinding efficiency, and the actual torque of the end effector is kept stable within a safe range during the grinding process.

[0070] In the control method of the aforementioned surgical robot system, bone mechanics information of the bone to be removed in the bone-grinding area is acquired. Based on the bone mechanics information, the friction coefficient information between the bone to be removed and the end effector of the surgical robot system is determined. Based on the friction coefficient information, the desired contact force between the end effector and the bone to be removed during the bone-grinding process is determined. This desired contact force is used to ensure that the end effector meets the desired torque during the bone-grinding process. In this embodiment, the controller determines the friction coefficient information between the end tool and the bone surface using the bone mechanics information of the bone to be removed. Combining the friction coefficient and the torque limit of the end effector, the desired contact force between the end effector and the bone surface is calculated. Through friction constraints, torque control is converted into contact force control. This allows the robotic arm to adjust the contact force between the end effector and the bone surface based on the desired contact force during the bone-grinding process. By adjusting the contact force, the end effector achieves higher grinding efficiency, ensuring that the contact force during the bone-grinding process is within the controllable range. This improves grinding efficiency and ensures safety during the surgical procedure.

[0071] In one exemplary embodiment, such as Figure 3 As shown, a control method for a surgical robot system is provided, the method comprising:

[0072] Step 302: Obtain the image grayscale information of the area to be ground from the three-dimensional image data of the area to be ground.

[0073] Step 304: Obtain the first mapping relationship between the pre-set image grayscale information and bone biomechanical information, and obtain the bone biomechanical information of the bone to be removed in the bone area to be ground based on the first mapping relationship and the image grayscale information.

[0074] The first mapping relationship is used to characterize the correspondence between the image grayscale in the three-dimensional bone image and the bone biomechanical information of the bone.

[0075] Step 306: Obtain the pre-set second mapping relationship, and determine the friction coefficient information between the bone to be removed and the end effector based on the second mapping relationship and the bone mechanics information of the bone to be removed.

[0076] The second mapping relationship is used to characterize the correspondence between the friction coefficient between the end effector and bone and bone biomechanical information.

[0077] For bones, higher hardness corresponds to a higher coefficient of friction. Bone hardness primarily depends on its mineral content, especially the content of hydroxyapatite crystals, and an increase in this mineral content directly increases bone density. In medical images obtained from CT or MRI scans, grayscale values ​​are directly correlated with bone density. Therefore, there is a direct or indirect mapping relationship between the coefficient of friction, hardness, bone density, and image grayscale values. This application's embodiments can collect data on different bone types through multiple samplings and calculate the first mapping relationship between image grayscale information and bone biomechanical information, as well as the second mapping relationship between bone biomechanical information and the coefficient of friction.

[0078] For example, please refer to Figure 4 In this embodiment of the application, the controller extracts the gray value G of the bone to be removed from the preoperative three-dimensional image, obtains the bone density ρ of the bone to be removed based on the first mapping relationship between image gray and bone density, such as ρ=f(G), and then determines the friction coefficient μ between the bone to be removed and the end effector based on the second mapping relationship between bone density and friction coefficient, such as μ=f(ρ,A).

[0079] Step 308: Based on the desired torque corresponding to the end effector and the structural parameters of the end effector, obtain the desired friction force of the end effector under the desired torque.

[0080] For example, during the bone grinding process, the optimal state is that the grinding drill can always operate at the desired torque, which is generally the rated torque of the grinding drill. If the built-in parameters of the grinding drill do not provide a rated torque, then the maximum output torque that the grinding drill can withstand without stalling can be used. The calculations are as follows; please refer to them further. Figure 4 , The desired torque can be expressed as:

[0081] ;

[0082] in, For safety factors, appropriate values ​​can be selected based on different environments.

[0083] Assuming the drill contacts the target object, i.e., the patient's conical plate, from its side, the distance from the contact point to the drill center is the drill radius r. burr The torque generated by friction is the largest, and the desired frictional force f can be obtained. d , represented as f d = / r burr .

[0084] Step 310: Combining the expected frictional force and the friction coefficient information, obtain the expected contact force corresponding to the contact point between the end effector and the bone grinding process.

[0085] For example, F can be obtained from the friction force calculation formula. d =f d / μ, after simplification, the final relation is:

[0086] ;

[0087] in, It is expressed as the expected contact force.

[0088] In a preferred embodiment, the present application can also collect different bone samples and calculate their gray values ​​and surface friction coefficients through multiple samplings. After integrating the obtained data, linearization processing is performed to directly obtain the correspondence between the friction coefficient between the end effector and the bone and the image gray value of the bone medical image. This correspondence is preset as a third mapping relationship. After the controller obtains the image gray value information of the bone to be removed, it can directly determine the friction coefficient information matching the image gray value information according to the preset third mapping relationship, such as μ=f(G).

[0089] In a preferred embodiment, the controller pre-obtains the planned grinding path corresponding to the area to be ground, determines the grayscale value of each path point on the planned grinding path using medical image information, and obtains the image grayscale information. The controller then obtains the bone density of each path point through a pre-set first mapping relationship and the grayscale value of each path point, and then determines the friction coefficient corresponding to each path point through a pre-set second mapping relationship and the bone density of each path point; alternatively, the controller can also directly determine the friction coefficient corresponding to each path point through a pre-set third mapping relationship and the grayscale value of each path point, and then calculate the expected contact force required for each path point.

[0090] In this embodiment, by mapping the friction coefficient to the grayscale of a bone medical image, the friction coefficient of the bone surface is determined based on the grayscale information of the bone to be removed. Then, the desired contact force is calculated using the friction coefficient and the desired frictional force of the end effector under the desired torque. The robotic arm can control the contact force between the drill and the bone surface. After determining the relationship between the desired contact force and the maximum output torque, the drill can achieve higher grinding efficiency by adjusting the contact force. Simultaneously, by directly mapping the friction coefficient to the image grayscale, the friction coefficient corresponding to the bone to be removed can be quickly obtained after determining the corresponding image grayscale value.

[0091] In an exemplary embodiment, prior to step 202, the control method of the surgical robot system may further include a step of determining the area to be ground. This step of determining the area to be ground may include: the controller acquiring a three-dimensional image of the target area of ​​the target object; in response to the selection operation of an initial region of interest in the three-dimensional image, the controller may segment different tissue materials of the initial region of interest and generate a three-dimensional model corresponding to the initial region of interest in combination with bone surface information, so that the operator can determine the target region of interest based on the three-dimensional model; in response to the selection operation of the target region of interest in the three-dimensional model corresponding to the initial region of interest, the controller extracts a first interface and a second interface from the target region of interest, and uses the first interface and the second interface to determine the area to be ground.

[0092] In this design, the first interface represents the upper surface of the bone within the target region of interest (ROI), and the second interface represents the safety interface above the boundary of the bone layer within the ROI. After extracting the first and second interfaces from the ROI, the controller uses the first interface as the initial surface for projecting the region to be ground along the sagittal axis and the second interface as the final surface for projecting the region to be ground along the sagittal axis, thus ultimately determining the region to be ground. For example, please refer to the reference... Figure 5 , Figure 6 and Figure 7 The surgeon can select a general surgical area, i.e., the initial region of interest 1, in the image view (e.g., Figure 5 , Figure 6 After the initial region of interest (ROI) 1 is confirmed, the controller can segment the patient's skin, soft tissue, and bone surface according to the image segmentation algorithm, extract vertebral surface information, and automatically generate a 3D contour model of the initial ROI 1 (e.g., Figure 7 This allows the surgeon to more directly observe the surgical area in order to determine the area to be shaved.

[0093] Please refer to the reference. Figure 8 and Figure 9 The surgeon selects the part to be polished in the 3D contour model and / or other views corresponding to the segmented initial region of interest 1, thus determining the target region of interest 10.

[0094] Please refer to the reference. Figure 10 and Figure 11 After determining the target region of interest 10, the controller can segment the upper surface of the bone within the target region of interest 10, i.e., the first interface 11. The controller can also segment a safety interface above the bone layer boundary 13 within the target region of interest 10, i.e., the second interface 12. For safety reasons, to avoid damage to nerves or tissues below the bone caused by debris generated during grinding of the lower surface 14 and by the vibration of the grinding drill, the controller extracts the complete bone layer boundary 13 from the target region of interest 10 and retains a preset thickness t as a safety boundary at the location of the bone layer boundary 13. t can be 1-2 mm, resulting in the second interface 12. Using the first interface 11 as the initial surface for projecting the bone region to be ground along the sagittal axis and the second interface 12 as the final surface for projecting the bone region to be ground along the sagittal axis, the bone region to be ground is finally determined.

[0095] In this embodiment, by combining imaging technology and segmentation algorithms, the target region of interest to be ground can be accurately planned. From a safety perspective, based on the target region of interest, a first interface is selected as the initial surface for the projection of the bone region to be ground along the sagittal axis, and a second interface is selected as the termination surface for the projection of the bone region to be ground along the sagittal axis, thereby determining the bone region to be ground, thus minimizing damage to nerves or tissues and improving safety.

[0096] In one exemplary embodiment, such as Figure 12 As shown, the control method of this surgical robot system also includes:

[0097] Step 1202: Determine the first interface and the second interface in the bone-grinding area.

[0098] The first interface 11 and the second interface 12 are the initial and final surfaces of the bone-grinding region projected along the sagittal axis, respectively. The first interface 11 can be the upper surface of the bone-grinding region, and the second interface 12 can be the lower surface of the bone-grinding region, with the second interface 12 located above the bone layer boundary corresponding to the bone-grinding region.

[0099] Step 1204: Using the first interface as the grinding start surface and the second interface as the grinding end surface, obtain the planned grinding path corresponding to the bone area to be ground; the planned grinding path is used to indicate the movement trajectory of the end effector during the bone grinding process in the bone area to be ground.

[0100] The planned grinding path includes at least one two-dimensional curve in the two-dimensional space where each grinding layer is located, and the multiple grinding layers are distributed layer by layer along the direction from the first interface to the second interface.

[0101] For example, the controller can use the upper surface of the area to be ground, i.e., the first interface 11, as the starting surface for grinding, and the lower surface of the area to be ground, i.e., the second interface 12, as the ending surface for grinding. Multiple grinding layers are distributed layer by layer along the direction from the first interface to the second interface. The planned grinding path includes at least one two-dimensional curve in the two-dimensional space where each grinding layer is located. For example, the two-dimensional curve can be a continuous curve, and each grinding layer has a first boundary and a second boundary. The two-dimensional curve circulates back and forth between the first boundary and the second boundary, and the two-dimensional curve does not intersect itself.

[0102] For example, please refer to Figure 13 and Figure 14 Following the planned grinding path from the first interface 11 to the second interface 12, the grinding drill starts from the upper surface, i.e., the first interface 11, and ends at the midpoint S of the frame line near the edge of the conical section on the upper surface (e.g., ...). Figure 11 , Figure 13 Using the grinding starting point as the starting point, perform an S-shaped reciprocating motion, traversing one layer to reach the end point E of that layer. Then, feed the grinding drill downwards to a fixed depth and repeat the above steps until the second interface 12 is reached.

[0103] Understandably, although the grinding layer path is described as a two-dimensional curve in a two-dimensional plane in this embodiment, in actual applications, due to the irregularity of the bone surface morphology, each grinding layer may have three-dimensional undulations. The two-dimensional curve is essentially a simplified representation of the actual three-dimensional path orthogonally projected onto an ideal reference plane, and its height deviation from the real bone surface can be accurately tracked through the real-time force-position compensation control of the surgical robot.

[0104] In one exemplary embodiment, such as Figure 15 As shown, step 1204 above may include:

[0105] Step 1502: Determine the percutaneous fixed point corresponding to the end effector; the percutaneous fixed point is located on the skin surface and is associated with the spatial position of the bone area to be ground.

[0106] For example, to meet the needs of minimally invasive surgery, a small incision is usually made on the skin surface as the percutaneous fixed point q for the drill. During bone reshaping, the drill needs to rotate around point q, the position of which is determined by the surgeon based on the location of the lesion. In this embodiment, an optical probe is used to calibrate the position of this percutaneous fixed point. First, the position of the probe is simultaneously displayed in the image on the host computer. The probe is placed on the skin surface, and the relative position of the probe and the lesion in the image is observed. Considering the angle of drill insertion and operation, point q is finally determined.

[0107] Step 1504: Use the percutaneous fixed point as the rotation reference point of the end effector to obtain multiple concentric circle paths.

[0108] Step 1506: Obtain the planned grinding path based on the multiple concentric circle paths.

[0109] The two-dimensional curve in the planned grinding path includes multiple sub-curves, and each sub-curve includes a circumferential segment of the concentric circular path within the bone to be ground.

[0110] For example, please continue to refer to Figure 13 and Figure 14 Using the first interface 11 as the initial surface, the controller moves within the plane according to... Figure 8 The planned rectangular frame automatically calculates and generates semi-elliptical regions within each grinding layer of the bone-grinding area, as well as concentric circular grinding paths within these semi-elliptical regions. The grinding drill, circumferentially around the percutaneous point, determines multiple concentric circular paths on each grinding layer. Under the boundary constraints of the semi-elliptical regions within the bone-grinding area, these concentric circular paths are truncated to obtain circumferential segments. The planned grinding path for each grinding layer includes these circumferential segments. Within the same concentric circle, the grinding path is planned layer by layer from the first interface to the second interface. Starting from the top surface, the grinding drill performs an S-shaped reciprocating motion through the aforementioned circumferential segments and the connecting curves between them. After traversing one layer, the grinding drill feeds downwards to a fixed depth, and then repeats the above steps until the second interface is reached.

[0111] In one optional implementation, the radial spacing between the plurality of concentric circular paths is determined based on the image grayscale information; wherein the radial spacing between concentric circular paths in the high grayscale region is smaller than the radial spacing between concentric circular paths in the low grayscale region, and the image grayscale value of the high grayscale region is greater than the image grayscale value of the low grayscale region.

[0112] In this embodiment, the grinding drill plans a concentric circle grinding path around the percutaneous fixed point, starting from the grinding start point. The density of the concentric circles is determined based on the gray value, and the density of the concentric circles is positively correlated with the gray value. That is, the larger the gray value, the greater the bone density, and the more meticulous the grinding is required, resulting in a denser concentric circle to ensure complete cutting.

[0113] In this embodiment, the planned grinding path for bone shaving is completed before surgery, allowing the surgeon to clearly see the area to be ground and the path of the drill, making the surgical process clearer. Simultaneously, by combining the planned grinding path with the image grayscale values ​​of each path point, the optimal contact force, i.e., the expected contact force, corresponding to each path point can be calculated preoperatively.

[0114] In one exemplary embodiment, such as Figure 16 As shown, the control method of this surgical robot system also includes:

[0115] Step 1602: Obtain a three-dimensional image of the target object and the target pose information of the optical marker of the target object in the three-dimensional image.

[0116] The three-dimensional image of the target object is used to indicate the three-dimensional image of the target area of ​​the target object, which includes the area of ​​bone to be removed. For example, the three-dimensional image of the target object could refer to a three-dimensional image of a patient's spinal segment.

[0117] Step 1604: The pose relationship between the optical markers of the end effector and the optical markers of the target object is acquired in real time using a vision camera.

[0118] Step 1606: Determine the end effector's optical marker in the three-dimensional image based on the target pose information and pose relationship of the target object.

[0119] Step 1608: Load the three-dimensional model of the end effector into the three-dimensional image of the target object using the end effector pose information to determine the relative position of the end effector and the target object.

[0120] For example, optical markers are attached to the drill and the patient's spine, and a visual camera is used to record the pose relationship between the two in real time, and a 4x4 transformation matrix is ​​used. Indicates (where, Optical markings indicating drilling. (Representing the patient's optical markers). A CT scan of the patient yields a three-dimensional image, from which the transformation matrix of the patient's optical markers in the image coordinate system is extracted. The pose information of the optical mark of the drill in the image coordinate system can be calculated, and can be expressed as: .

[0121] A 3D model of the drill was constructed using 3D software, and the position of the drill's optical markers in the image was determined. The rigid connection between the optical marker and the drill is established, and the 3D model of the drill is loaded into the image. The fused image is then presented in the host computer, allowing the surgeon to clearly and intuitively observe the drill's operation even when the surgical area is obscured by the drill or skin tissue.

[0122] In this embodiment, visual and imaging technologies are used to improve the precision of bone grinding. The area to be ground and the position of the grinding drill are determined by combining visual and CT images. The position and posture of the grinding drill can be modeled in the images and displayed in real time by 3D software, so that the surgeon can perceive the relative position of the grinding drill and the spine in real time and accurately.

[0123] In one exemplary embodiment, such as Figure 17 As shown, the control method of this surgical robot system also includes:

[0124] Step 1702: Obtain the current grinding information of the end effector during the bone grinding process of the bone to be removed. The current grinding information includes the current position, current feedback force, and current speed of the end effector.

[0125] The current feedback force of the end effector can refer to the component of the contact force between the end effector and the current bone contact point in the current displacement direction.

[0126] Step 1704: Determine the target position information of the end effector using the expected grinding information and the current grinding information of the end effector.

[0127] The desired grinding information includes the desired position, the desired contact force corresponding to the desired position, and a preset desired speed; the desired position is determined based on the planned grinding path. The target position information refers to the target position of the end effector in the next step.

[0128] Step 1706: Output motion commands to control the robotic arm based on the target position information of the end effector.

[0129] For example, the sensing device 300 of the surgical robot system can be a six-dimensional force sensor. The bone grinding process uses robotic arm admittance control based on the six-dimensional force sensor at the end, which can complete compliant motion in six degrees of freedom. However, under a predetermined multi-segment straight trajectory, if the robotic arm deviates from the trajectory, it is impossible to determine whether the grinding has been completed. Therefore, in this embodiment, force control can be used only in the high-speed grinding drill displacement direction. The force control model design is as follows:

[0130] ;

[0131] Where 'a' represents the desired acceleration of the end effector, and F, V, and X are the component of the current contact force in the current displacement direction, the current velocity, and the current position of the tool, respectively. d V d X d These represent the desired contact force, desired velocity, and desired position, respectively; B is the damping coefficient; K is the stiffness coefficient; and M is the mass coefficient.

[0132] Among them, the expected contact force F d Expected speed V d and expected position X d The desired position can be determined as follows: the next position of the end effector determined according to the planned grinding path; the desired contact force can be the desired contact force between the end effector and the grinding bone at the desired position, determined based on the friction coefficient information in step 206 above; the desired speed can be the limit speed at which the grinding drill does not stall, which can be tested through constant speed grinding and assigned to V. d .

[0133] The current position X, current feedback force F, and current velocity V of the end effector can be determined as follows: the force component F of the end effector 400 can be obtained through the sensing device 300. p The robotic arm can obtain the velocity component V in the base coordinate system (the geodetic coordinate system, also known as the world coordinate system). b and position component X b The velocity component V needs to be... b and position component X b From the base coordinate system to the end effector, i.e., the tool end, where:

[0134] ;

[0135] ;

[0136] In the formula, b refers to the base coordinate system, and f refers to the flange coordinate system. Then, the three components need to be projected onto the displacement direction to obtain the displacement direction represented in the tool coordinate system as Dir, which is a unit vector. Then the following transformation occurs:

[0137] ;

[0138] ;

[0139] ;

[0140] After calculating the desired acceleration 'a' of the end effector using the force control model described above, the desired acceleration 'a' of the end effector needs to be mapped back to the base coordinate system through coordinate transformation:

[0141] ;

[0142] Among them, a b The desired acceleration of the end effector in the base coordinate system.

[0143] Then a b By performing two integrations, we obtain the position vector x of the end effector for the next step. b This is used as the target position information of the end effector in the base coordinate system.

[0144] In this embodiment, the force control model based on admittance control takes the difference between the current feedback force and the desired contact force as the dominant factor, which is the core driver for generating acceleration and the next position vector. The difference between the current position and the desired position, and the difference between the current velocity and the desired velocity, are used as dynamic responses to correct the force control, thereby converting the difference in distance from the desired contact force into acceleration commands. Then, displacement commands are generated through integration, and finally executed by the closed-loop position control of the robotic arm.

[0145] For example, in determining the target position information of the end effector, i.e., the position vector x for the next step... b Subsequently, the controller outputs motion commands to control the robotic arm based on the target position information. Because minimally invasive surgery requires small incisions, typically creating a channel on the skin surface 10-15 cm from the lesion, the grinding method of the robotic arm driving the high-speed drill cannot be achieved through pure positional translation; the drill must rotate around the incision, i.e., the percutaneous fixed point. Let the center position of the surface incision be x. sur After determining the position of the drill tip, i.e., the target position information x b After that, with x sur To x b The three-dimensional vector is the Z direction of the end effector. The other two directions are solved with the minimum energy consumption as the standard. Finally, the angles of each joint are solved by the inverse kinematics of the robotic arm. The controller sends multiple sets of joint point information, including the angles of each joint, as motion commands to the robotic arm system.

[0146] In this embodiment, the sensing device 300 of the surgical robot system can be a six-dimensional force sensor. The robotic arm can apply a six-degree-of-freedom robotic arm admittance control method based on the end-effector six-dimensional force sensor. The robotic arm based on the end-effector six-dimensional force sensor performs adaptive contact force bone grinding based on the desired contact force, and controls the contact force between the high-speed drill and the bone in real time. This ensures that the contact force during the bone grinding process is within the control range, and that bone grinding is completed at the fastest grinding rate on the optimal path.

[0147] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0148] It is understood that the term "based on" as used in this application is used to describe one or more factors that influence the determination, but does not exclude other factors that may influence the determination. For example, the phrase "determine A based on B" means that the determination of A can be based entirely or at least partially on factor B. That is, B is a factor that influences the determination of A, but does not exclude the fact that the determination of A is also based on C.

[0149] Based on the same inventive concept, this application also provides a surgical robot system. The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of one or more surgical robot system embodiments provided below can be found in the limitations of the control method of the surgical robot system above, and will not be repeated here.

[0150] In one exemplary embodiment, the surgical robot system includes a robotic arm 200, an end effector 400, and a controller 100. The end effector 400 is connected to the end of the robotic arm 200 and is used to perform bone grinding operations under the drive of the robotic arm 200.

[0151] The surgical robot system may also include a sensor 300, which is fixed to the end of the robotic arm 200 and the end effector 400 is fixedly mounted on the sensor 300.

[0152] The controller 100 is connected to the robotic arm 200 and the sensing device 300 respectively. The controller 100 includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it implements the steps of the control method of the surgical robot system described above.

[0153] In one exemplary embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 18As shown, the computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input / output interface is used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a control method for a surgical robot system. The display unit is used to form a visually visible image and can be a display screen, projection device, or virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0154] Those skilled in the art will understand that Figure 18 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0155] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0156] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0157] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A control method for a surgical robot system, characterized in that, The method includes: Obtain bone mechanics information of the bone to be removed in the area to be ground down; Based on the bone mechanics information, the friction coefficient between the bone to be removed and the end effector of the surgical robot system is determined. Based on the friction coefficient information, the desired contact force between the end effector and the bone to be removed during the bone grinding process is determined; the desired contact force is used to ensure that the end effector meets the desired torque during the bone grinding process; The method further includes: A first interface and a second interface are defined in the bone-grinding region; the first interface is the upper surface of the bone-grinding region, and the second interface is located above the bone layer boundary corresponding to the bone-grinding region. Using the first interface as the grinding start surface and the second interface as the grinding end surface, a planned grinding path corresponding to the bone area to be ground is obtained; the planned grinding path is used to indicate the movement trajectory of the end effector during the bone grinding process in the bone area to be ground; wherein, the planned grinding path includes at least one two-dimensional curve in the two-dimensional space where each grinding layer is located, and multiple grinding layers are distributed layer by layer along the direction from the first interface to the second interface. Obtaining the planned grinding path corresponding to the bone region to be ground includes: Determine the percutaneous fixed point corresponding to the end effector; the percutaneous fixed point is located on the skin surface and is associated with the spatial position of the area to be bone-reduced. Using the percutaneous fixed point as the rotation reference point of the end effector, multiple concentric circle paths are obtained; The planned grinding path is obtained based on multiple concentric circle paths; the two-dimensional curve in the planned grinding path includes multiple sub-curves, and the multiple sub-curves include the circumferential segments of the multiple concentric circle paths in the bone area to be ground.

2. The method according to claim 1, characterized in that, The step of determining the coefficient of friction between the bone to be removed and the end effector of the surgical robot system based on the bone mechanics information includes: A pre-set first mapping relationship is obtained, and the bone biomechanical information of the bone to be removed is obtained based on the first mapping relationship and the image grayscale information of the bone medical image. The first mapping relationship is used to characterize the correspondence between image grayscale and bone biomechanical information. A pre-set second mapping relationship is obtained, and the friction coefficient information between the bone to be removed and the end effector is determined based on the second mapping relationship and the bone mechanics information of the bone to be removed; the second mapping relationship is used to characterize the correspondence between the friction coefficient between the end effector and the bone and the bone mechanics information.

3. The method according to claim 1 or 2, characterized in that, Determining the desired contact force between the end effector and the bone to be removed during the bone grinding process based on the friction coefficient information includes: Based on the desired torque corresponding to the end effector and the structural parameters of the end effector, the desired friction force of the end effector under the desired torque is obtained; By combining the desired frictional force and the friction coefficient information, the desired contact force between the end effector and the bone to be removed during the bone grinding process is obtained.

4. The method according to claim 1, characterized in that, The radial spacing between the multiple concentric circular paths is determined based on the image grayscale information of the bone medical image of the bone to be removed; wherein, the radial spacing between the concentric circular paths in the high grayscale region is smaller than the radial spacing between the concentric circular paths in the low grayscale region, and the image grayscale value of the high grayscale region is greater than the image grayscale value of the low grayscale region.

5. A surgical robot system, characterized in that, include: robotic arm; An end effector, connected to the end of the robotic arm, is used to perform bone grinding operations under the drive of the robotic arm; A controller, connected to the robotic arm, includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method according to any one of claims 1 to 4.

6. The system according to claim 5, characterized in that, When the processor executes the computer program, it also performs the following steps: The current grinding information of the end effector during the bone grinding process of the bone to be removed is obtained, and the current grinding information includes the current position, current feedback force and current speed of the end effector; The target position information of the end effector is determined by using the expected grinding information and the current grinding information of the end effector; the expected grinding information includes the expected position of the end effector, the expected contact force corresponding to the expected position, and the preset expected speed; the expected position is determined according to the planned grinding path; The robot arm outputs motion commands based on the target position information of the end effector, and the robot arm is used to drive the end effector to perform bone grinding operations; the motion commands are used to indicate multiple sets of joint information that the robot arm needs to move.

7. The system according to claim 5, characterized in that, When the processor executes the computer program, it also performs the following steps: Acquire a three-dimensional image of the target object and the target pose information of the optical marker of the target object in the three-dimensional image; The pose relationship between the optical markers of the end effector and the optical markers of the target object is acquired in real time using a vision camera. Based on the target pose information and pose relationship of the target object, determine the end-effector pose information in the three-dimensional image of the optical marker of the end effector; The three-dimensional model of the end effector is loaded into the three-dimensional image of the target object using the end effector pose information to determine the relative position of the end effector and the target object.

8. A computer device comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

9. The computer device according to claim 8, characterized in that, When the computer program is executed by the processor, it also performs the following steps: The current grinding information of the end effector during the bone grinding process of the bone to be removed is obtained, and the current grinding information includes the current position, current feedback force and current speed of the end effector; The target position information of the end effector is determined by using the expected grinding information and the current grinding information of the end effector; the expected grinding information includes the expected position of the end effector, the expected contact force corresponding to the expected position, and the preset expected speed; the expected position is determined according to the planned grinding path; The robot arm outputs motion commands based on the target position information of the end effector, and the robot arm is used to drive the end effector to perform bone grinding operations; the motion commands are used to indicate multiple sets of joint information that the robot arm needs to move.

10. The computer device according to claim 8, characterized in that, When the computer program is executed by the processor, it also performs the following steps: Acquire a three-dimensional image of the target object and the target pose information of the optical marker of the target object in the three-dimensional image; The pose relationship between the optical markers of the end effector and the optical markers of the target object is acquired in real time using a vision camera. Based on the target pose information and pose relationship of the target object, determine the end-effector pose information in the three-dimensional image of the optical marker of the end effector; The three-dimensional model of the end effector is loaded into the three-dimensional image of the target object using the end effector pose information to determine the relative position of the end effector and the target object.

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