Medical robot, control method of mechanical arm of medical robot, electronic equipment and medium

Abstract

The invention discloses a control method for a mechanical arm of a medical robot, which comprises the following steps: determining the magnitude and direction of a force applied to a tail end joint of a surgical instrument in real time, the surgical instrument being mounted on the tail end joint of the mechanical arm; under the condition that the force borne by the tail end of the surgical instrument is smaller than a first set threshold value, the direction opposite to the direction of the force borne by the tail end of the surgical instrument serves as the traction direction, and the operation point of the surgical instrument on the body of the patient serves as a fixed point; the rotation speed and the rotation direction of the mechanical arm around the fixed point and the axial translation speed and the axial translation direction of the mechanical arm relative to the fixed point are determined; and the mechanical arm is controlled to move according to the rotating speed and the rotating direction of the mechanical arm around the fixed point and the axial translation speed and the axial translation direction of the mechanical arm relative to the fixed point. The invention further provides electronic equipment, a computer readable medium and a medical robot.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to a medical robot, a control method for the robotic arm of the medical robot, an electronic device, and a computer-readable medium. Background Technology

[0002] Minimally invasive surgery requires the use of medical instruments such as laparoscopes and thoracoscopes. Robots used in minimally invasive surgery typically include robotic arms for operating the endoscope, as well as multiple robotic arms for retracting tissues and exposing the surgical area. To ensure adequate exposure of the surgical area throughout the procedure, surgeons need to frequently operate the multiple robotic arms retracting tissues in a master-slave configuration, increasing their workload. Summary of the Invention

[0003] This invention aims to address, to a certain extent, one of the technical problems in related technologies. To this end, this invention provides a medical robot, a control method for the robotic arm of the medical robot, an electronic device, and a computer-readable medium. Using the control method to control the robotic arm of the medical robot can reduce the workload of doctors.

[0004] As a first aspect of the present invention, a control method for a robotic arm of a medical robot is provided, wherein the control method includes: The magnitude and direction of the force on the end of the surgical instrument are determined in real time, wherein the surgical instrument is mounted on the end joint of the robotic arm; When the force on the end of the surgical instrument is less than a first set threshold, the direction opposite to the direction of the force on the end of the surgical instrument is taken as the traction direction, and the operation point of the surgical instrument is taken as the fixed point. The rotational speed and direction of the end joint of the robotic arm about the fixed point, as well as the axial translational speed and direction of the end joint of the robotic arm relative to the fixed point are determined. The end joint of the robotic arm is controlled to move according to the rotational speed and direction of the end joint of the robotic arm about the fixed point, and the axial translational speed and direction of the end joint of the robotic arm relative to the fixed point.

[0005] Optionally, the step of taking the direction opposite to the direction of the force applied to the end of the surgical instrument as the traction direction, and taking the operating point of the surgical instrument as the fixed point, to determine the rotational speed and direction of the robotic arm about the fixed point, as well as the axial translational speed and direction of the robotic arm relative to the fixed point, includes: Construct the Jacobian matrix based on the coordinates Tool_P of the origin of the surgical instrument's coordinate system in the patient's coordinate system; The pulling direction is projected onto the motion space that satisfies the centroid constraint using the constructed Jacobian matrix to obtain a 6-dimensional target vector. In the target vector, the first 3 dimensions are the axial translational velocity of the robotic arm relative to the fixed point, and the last 3 dimensions are the rotational velocity of the robotic arm around the fixed point.

[0006] Optionally, in the step of constructing the Jacobian matrix based on the coordinates of the origin of the surgical instrument in the patient's coordinate system, the Jacobian matrix is ​​constructed using the following formula: J_rcm=[I3-Tool_P × ]; Where J_rcm is the Jacobian matrix; I3 is a third-order identity matrix; Tool_P × The oblique symmetric operator for the coordinates of Tool_P, the origin of the surgical instrument coordinate system, in the patient coordinate system.

[0007] Optionally, the real-time determination of the magnitude and direction of the force acting on the tip of the surgical instrument includes: The magnitude and direction of the force acting on the end joint of the robotic arm are acquired in real time. Based on the installation method of the surgical instrument and the end joint of the robotic arm, as well as the length of the surgical instrument and the position of the operating point, calculate the magnitude and direction of the force on the end of the surgical instrument. Alternatively, data from a sensor installed at the end of the surgical instrument can be acquired in real time to determine the magnitude and direction of the force acting on the end of the surgical instrument.

[0008] Optionally, the real-time determination of the magnitude and direction of the force acting on the tip of the surgical instrument includes: The force on the end joint of the robotic arm is detected by a three-dimensional force sensor installed on the end joint of the robotic arm; Calculate the force on the tip of the surgical instrument using the following formula: F_head = (Tool_P × Fext_P) × Tool_P / ||Head_P|| 2 ; Head_P = Tool_P - Tool_P / ||Tool_P|| * L; Fext_P = T_P_t * (-Fext_t_arm); Wherein, F_head is the force exerted on the end of the surgical instrument; Tool_P is the coordinate of the origin of the surgical instrument coordinate system in the patient coordinate system, where the fixed point is the origin of the patient coordinate system and the fulcrum for calculating the torque; Fext_P is the force applied to the surgical instrument by the end joint of the robotic arm in the patient coordinate system; Head_P is the coordinate of the end of the surgical instrument in the patient coordinate system; L is the length of the surgical instrument; T_P_t is the transformation matrix from the patient coordinate system to the surgical instrument coordinate system; Fext_t_arm is the force detected by the force sensor.

[0009] Optionally, the control method further includes: When the force on the end of the surgical instrument reaches a second preset threshold, the robotic arm is controlled to stop moving.

[0010] Optionally, the control method further includes: Receive active mode trigger signal; In response to the active mode trigger signal, the step of determining the magnitude and direction of the force applied to the end of the surgical instrument in real time is performed.

[0011] Optionally, the control method further includes at least one of the following steps: Receive a mode switching signal, and in response to the mode switching signal, control the robotic arm to exit the current mode and enter the mode associated with the mode switching signal; Upon receiving a follow-up mode trigger signal, and in response to the follow-up mode trigger signal, release the position control of the robotic arm so that the robotic arm can move to the target position under the influence of an external dragging force. The lock mode trigger signal is received to keep the pose of the robotic arm unchanged.

[0012] As a second aspect of the present invention, an electronic device is provided, comprising: One or more processors; A memory having stored one or more computer programs that, when executed by one or more processors, cause the one or more processors to implement the control method provided in the first aspect of the invention.

[0013] As a third aspect of the invention, a computer-readable medium is provided having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the control method provided in the first aspect of the invention.

[0014] As a fourth aspect of the present invention, a medical robot is provided, the medical robot including electronic equipment and at least one robotic arm for traction of tissues, the end joint of the robotic arm being used for mounting surgical instruments, wherein the electronic equipment is the electronic equipment provided in the second aspect of the present invention.

[0015] Optionally, the medical robot further includes at least one three-dimensional force sensor disposed on the end joint of the robotic arm to detect the force exerted on the end joint of the robotic arm.

[0016] In this embodiment of the invention, the force on the distal end of the surgical instrument is analyzed in real time. Once the force on the distal end of the surgical instrument is found to be lower than a first preset threshold, the robotic arm is triggered to move in the opposite direction of the traction force. This causes the traction force of the surgical instrument on the patient's tissue to increase, thereby ensuring a good surgical field of vision. By controlling the robotic arm through the aforementioned control method, the robotic arm can move autonomously and adjust the traction direction according to the force on the distal end of the surgical instrument. When the traction of the surgical instrument loosens, the doctor does not need to operate the robotic arm, reducing the doctor's workload. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings: Figure 1 This is a schematic diagram showing the relative positional relationship between the robotic arm and the surgical instruments; Figure 2 This is a flowchart illustrating one embodiment of the control method provided by the present invention; Figure 3 This is a flowchart illustrating another embodiment of the control method provided by the present invention; Figure 4 This is a flowchart of one implementation of step S120; Figure 5 This is a schematic diagram of a module of one embodiment of the electronic device provided by the present invention; Figure 6 This is a schematic diagram of the modules of the computer-readable medium provided by the present invention.

[0018] Explanation of reference numerals in the attached figures 101: Processor; 102: Memory 103: I / O Interface 104: Bus 100: Surgical instruments; 200: Robotic arms 300: Mechanical interface Detailed Implementation Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described are intended to explain the present invention and should not be construed as limiting the invention.

[0019] The terms "an embodiment," "example," or "trademark" used in this specification refer to a particular feature, structure, or characteristic described in connection with the embodiment itself that may be included in at least one embodiment disclosed in this invention. The phrase "in an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0020] like Figure 1 As shown, the surgical instrument 100 is mounted on the end joint of the robotic arm 200 of a medical robot. During laparoscopic surgery, holes are made in the patient's body (e.g., in the abdominal wall during laparoscopic surgery), and the surgical instrument 100 passes through these holes. In this embodiment of the invention, the surgical instrument 100 can be a retraction forceps, clamping forceps, traction member, or other instrument whose end can be connected to tissue or other instruments, as well as a surgical instrument that can be handheld or motor-driven.

[0021] like Figure 1 As indicated by the annotations, three coordinate systems exist in the above application scenario: the robotic arm world coordinate system, which is usually provided by the robotic arm manufacturer, but can also be defined by the user. For example, the origin of the robotic arm can be used as the origin of the robotic arm world coordinate system, the direction perpendicular to the ground and pointing upwards can be used as the Z-axis of the world coordinate system, and the X-axis and Y-axis of the world coordinate system can be set on a horizontal plane; the patient coordinate system (in this embodiment of the invention, the patient coordinate system is a constrained coordinate system), the origin of which is located at the punching point on the patient's abdominal wall, and the X-axis of the patient coordinate system is perpendicular to the world coordinate system. The X-axis of the surgical instrument coordinate system is parallel to the Y-axis of the patient coordinate system and the Y-axis of the world coordinate system; the Z-axis of the patient coordinate system is parallel to the Z-axis of the world coordinate system. The origin of the surgical instrument coordinate system is located at the intersection of the axis of the end joint of the robotic arm and the axis of the surgical instrument. The X-axis of the surgical instrument coordinate system is the same as the X-axis of the end joint coordinate system of the robotic arm; the Y-axis of the surgical instrument coordinate system is the same as the Y-axis of the end joint coordinate system of the robotic arm; the Z-axis of the surgical instrument coordinate system is the same as the Z-axis of the end joint coordinate system of the robotic arm.

[0022] To facilitate understanding of the concept of this invention, the relationships between several coordinate systems and their transformation methods are introduced below.

[0023] Once the relative positions of the patient and the robotic arm are fixed, the distance from the world coordinate system to the patient coordinate system T_0_P is also fixed. The patient coordinate system T_0_P can be determined as follows: The end of the surgical instrument is moved to the perforation point on the patient's abdominal wall, and the transformation matrix T_0_n from the robot arm's world coordinate system to the robot arm's end joint coordinate system is obtained through the robot arm's forward kinematics. The single-joint transformation matrix of the robotic arm's forward kinematics is as follows: ; in, i Number the joints of the robotic arm; α i For the first robotic arm i The angle between the axis of a joint and the axis of an adjacent joint; θ i For the first robotic arm i The range of rotation of a joint around its own axis; d i For the first robotic arm i Offset of joints.

[0024] Figure 1 As shown, θ 1 represents the range of rotation of the first joint of the robotic arm around its own axis; θ 2 represents the range of rotation of the second joint of the robotic arm around its own axis; θ 3 represents the range of rotation of the third joint of the robotic arm around its own axis; θ 4 represents the range of rotation of the fourth joint of the robotic arm around its own axis; θ 5 represents the range of rotation of the fifth joint of the robotic arm around its own axis; θ 6 represents the range of rotation of the sixth joint of the robotic arm around its own axis; θ 7 represents the range of rotation of the 7th joint of the robotic arm around its own axis.

[0025] Accordingly, the coordinate transformation matrix from the m-th joint (containing the degrees of freedom of the m-th joint) to the n-th joint can be represented by the following formula (1): (1) Typically, the joint connected to the base of the robotic arm is the first joint, and the end joint of the robotic arm is the nth joint. Usually, n is 6 or 7. The transformation matrix T_0_n from the coordinate system of the base to the coordinate system of the end joint can be calculated using the above formula (1).

[0026] It should be noted that the transformation matrix from the coordinate system of the robotic arm's end effector joint to the coordinate system of the surgical instrument is determined by the mechanical mounting method of the surgical instrument. Since the end effector joint of the robotic arm and the surgical instrument are fixedly connected, and the length L of the surgical instrument is a fixed value, the transformation matrix from the coordinate system of the robotic arm's end effector joint to the coordinate system of the surgical instrument is a constant matrix, denoted here as T_n_t.

[0027] The transformation matrix from the world coordinate system of the robotic arm to the coordinate system of the surgical instrument is T_0_t = T_0_t * T_n_t.

[0028] The transformation matrix T_0_P from the robot's world coordinate system to the patient's coordinate system can be determined in the following way: Since the end joint of the robotic arm is fixedly connected to the surgical instrument 100, the coordinates of the end of the surgical instrument in the end joint coordinate system of the robotic arm are constant, denoted as P(x,y,z).

[0029] When the end of the surgical instrument is moved to the punching point on the patient's abdominal wall, the transformation matrix T_0_n from the world coordinate system to the coordinate system of the end joint of the robotic arm is obtained through the forward kinematics of the robotic arm. Through coordinate transformation, the coordinates of the end point of the surgical instrument (i.e. the punching point on the patient's abdominal wall) in the world coordinate system can be obtained as P_0_p = T_0_n * P(x,y,z).

[0030] Given that the coordinate axes of the patient coordinate system and the world coordinate system are in the same direction, and the origin of the patient coordinate system is at coordinate P_0_p in the world coordinate system, the distance from the world coordinate system to the patient coordinate system T_0_P can be obtained, as shown in the following formula (2): (2); Wherein, P_0_p(1) is the X-axis coordinate of the patient's origin in the world coordinate system; P_0_p(2) is the Y-axis coordinate of the patient's origin in the world coordinate system; P_0_p(3) is the Z-axis coordinate of the patient's origin in the world coordinate system.

[0031] It should be noted that using the end point of the surgical instrument to mark the origin of the patient coordinate system is only an optional implementation of this invention. Any mark point on the surgical instrument can be used to mark the origin of the patient coordinate system.

[0032] As a first aspect of the present invention, a control method for the robotic arm of a medical robot is provided, wherein, as Figure 2 As shown, the control method includes: In step S110, the magnitude and direction of the force on the end of the surgical instrument are determined in real time, wherein the surgical instrument is mounted on the end joint of the robotic arm. In step S120, when the force on the end of the surgical instrument is less than a first set threshold, the direction opposite to the direction of the force on the end of the surgical instrument is taken as the traction direction, and the operation point of the surgical instrument on the patient is taken as the fixed point. The rotational speed and direction of the end joint of the robotic arm around the fixed point, as well as the axial translational speed and direction of the end joint of the robotic arm relative to the fixed point are determined. In step S130, the end joint of the robotic arm is controlled to move according to the rotational speed and direction of the end joint of the robotic arm about the fixed point, and the axial translational speed and direction of the end joint of the robotic arm relative to the fixed point.

[0033] During minimally invasive surgery, due to tissue characteristics, the traction of surgical instruments used for pulling loosens as the surgeon cuts, and correspondingly, the force on the end of the surgical instrument decreases. In this embodiment of the invention, the force on the end of the surgical instrument is analyzed in real time. Once it is found that the force on the end of the surgical instrument is lower than a first set threshold, the robotic arm can be triggered to move in the opposite direction of the pulling force. This restores the pulling force of the surgical instrument on the patient's tissue, thereby ensuring a good surgical field of view. By controlling the robotic arm through the aforementioned control method, the robotic arm can move autonomously and adjust the pulling direction according to the force on the end of the surgical instrument. When the traction of the surgical instrument loosens, the surgeon does not need to operate the robotic arm, reducing the surgeon's workload.

[0034] As mentioned above, robotic arms have a number of degrees of freedom (usually 6 or 7). In order to control the movement of surgical instruments, robotic arms need to perform axial translation and rotation. Therefore, after determining the traction direction, using the fixed point as a constraint, the rotational speed and direction of the robotic arm around the fixed point, as well as the axial translational speed and direction of the robotic arm relative to the fixed point, can be further determined, thereby realizing the control of the robotic arm and enabling the surgical instruments to produce the required traction movement.

[0035] The "fixed point" here refers to the "drilling point" mentioned above, which is also the telecentric point. In this embodiment of the invention, by dynamically constraining the telecentric point, it is possible to ensure that the surgical instruments move around the drilling point (or incision point), thereby avoiding unnecessary damage to the patient's tissues due to displacement of the surgical instruments relative to the drilling point and ensuring the safety of the surgical procedure.

[0036] As mentioned above, the surgical instruments are instruments such as traction forceps, clamping forceps, and traction components, whose ends can be connected to tissues or other instruments. During the operation, the ends of the surgical instruments clamp or hook onto the tissues in the patient's body, forming traction points on the tissues. These "traction points" are different from the "operation points" mentioned above.

[0037] In this embodiment of the invention, there are no special limitations on how step S120 is specifically executed, as long as the movement of the surgical instrument can be decomposed into rotational motion about the fixed point and axial translational motion relative to the fixed point. Optionally, as Figure 4 As shown, the step of taking the direction opposite to the direction of the force applied to the end of the surgical instrument as the traction direction, and taking the operating point of the surgical instrument as the fixed point, determining the rotational speed and direction of the robotic arm about the fixed point, as well as the axial translational speed and direction of the robotic arm relative to the fixed point, includes: In step S121, a Jacobian matrix is ​​constructed based on the coordinates Tool_P of the origin of the surgical instrument's coordinate system in the patient's coordinate system; In step S122, the pulling direction is projected onto the motion space that satisfies the centroid constraint using the constructed Jacobian matrix to obtain a 6-dimensional target vector. In the target vector, the first 3 dimensions are the axial translational velocity of the robotic arm relative to the fixed point, and the last 3 dimensions are the rotational velocity of the robotic arm around the fixed point.

[0038] Specifically, in the step of constructing the Jacobian matrix based on the coordinates Tool_P of the origin of the surgical instrument's coordinate system in the patient's coordinate system, the Jacobian matrix is ​​constructed using the following formula (3): J_rcm=[I3-Tool_P × (3); Where J_rcm is the Jacobian matrix; I3 is a third-order identity matrix; Tool_P × The oblique symmetric operator for the coordinates of Tool_P, the origin of the surgical instrument coordinate system, in the patient coordinate system.

[0039] The Jacobian matrix is ​​the identity matrix and Tool_P × The augmented matrix, in the Jacobian matrix, has the first three columns corresponding to the translational degrees of freedom of the surgical instrument's end point, and the last three columns corresponding to the end motion of the surgical instrument mapped to the linear velocity about the fixed point, thereby ensuring that the rod of the surgical instrument can always pass through the punching point.

[0040] In step S122, the projection of the pulling direction onto the motion space that satisfies the centroid constraint can be represented by the following formula (4): v_robot= J_rcm'*v_head_direction(4); Wherein, v_robot is a 6-dimensional vector, the first 3 dimensions being the axial translational velocity of the end joint of the robotic arm relative to the fixed point, and the last 3 dimensions being the rotational velocity of the end joint of the robotic arm around the fixed point. J_rcm' is the pseudo-inverse of the Jacobian matrix; v_head_direction is the desired direction of movement of the end of the surgical instrument.

[0041] When a medical robot performs tissue traction during surgery, the direction of motion of the surgical instrument's end point is opposite to the direction of the force applied to it. Therefore, the direction of motion of the surgical instrument's end point can be defined using the following formula (5): v_head_direction = - F_head / ||F_head|| (5).

[0042] Wherein, F_head is the force exerted on the end of the surgical instrument.

[0043] In this embodiment of the invention, no special limitation is made on how to determine the force at the end of the surgical instrument. For example, a force sensor can be installed at the end joint of the robotic arm to detect the force at the end joint of the robotic arm and calculate the force at the end of the surgical instrument.

[0044] Specifically, the real-time determination of the magnitude and direction of the force acting on the tip of the surgical instrument includes: The step involves acquiring the force on the end of the robotic arm detected by a force sensor installed at the end of the robotic arm. The force on the end of the surgical instrument is calculated according to the following formulas (6) to (8).

[0045] F_head = (Tool_P × Fext_P) × Tool_P / ||Head_P|| 2 (6); Head_P = Tool_P - Tool_P / ||Tool_P|| * L (7); Fext_P = T_P_t * (-Fext_t_arm)(8); Wherein, F_head is the force exerted on the end of the surgical instrument; Tool_P is the coordinate of the origin of the surgical instrument coordinate system in the patient coordinate system, where the fixed point is the origin of the patient coordinate system and the fulcrum for calculating the torque; Fext_P is the force applied to the surgical instrument by the end joint of the robotic arm in the patient coordinate system; Head_P is the coordinate of the end of the surgical instrument in the patient coordinate system; L is the length of the surgical instrument; T_P_t is the transformation matrix from the patient coordinate system to the surgical instrument coordinate system; Fext_t_arm is the force detected by the force sensor.

[0046] In this embodiment of the invention, the force detected by the three-dimensional force sensor at the end joint of the robotic arm is denoted as Fext_t_arm. According to Newton's third law, the force exerted on the mechanical interface 300 of the surgical instrument, which is used to connect with the end joint of the robotic arm, is -Fext_t_arm.

[0047] Accordingly, in the patient coordinate system, the force exerted by the robotic arm 200 on the mechanical interface 300 of the surgical instrument 100 is Fext_P = T_P_t * (-Fext_t_arm).

[0048] When calculating the force received at the end of the surgical instrument while it is in static equilibrium, the position of the perforation point is used as the fulcrum and origin, and the static equilibrium equation (9) is written for the surgical instrument: Tool_P × Fext_P + Head_P × F_head = 0 (9).

[0049] After correcting the order of the cross product, the force exerted on the end of the surgical instrument 100 can be obtained: F_head = (Tool_P × Fext_P) × Tool_P / ||Head_P|| 2 .

[0050] As another optional embodiment of the present invention, the force on the joint can be calculated by the current of the joint motor, and then the force on the end of the surgical instrument can be calculated by force mapping.

[0051] In another optional embodiment of the present invention, force sensors can be installed at each joint of the robotic arm to calculate the force on the distal end of the surgical instrument through force mapping. Accordingly, the real-time determination of the magnitude and direction of the force on the distal end of the surgical instrument includes: The magnitude and direction of the force acting on the end joint of the robotic arm are acquired in real time. Based on the installation method of the surgical instrument and the end joint of the robotic arm, as well as the length of the surgical instrument and the position of the operating point, the magnitude and direction of the force on the end of the surgical instrument are calculated.

[0052] Of course, some surgical instruments have built-in force sensors at their ends, which can directly detect the force applied to the end. For surgical instruments without force sensors at the end, force sensors can be installed at the end of the instrument. Accordingly, the real-time determination of the magnitude and direction of the force applied to the end of the surgical instrument includes: Data from sensors installed at the end of the surgical instrument are acquired in real time to determine the magnitude and direction of the force acting on the end of the surgical instrument.

[0053] In this embodiment of the invention, no special limitation is made on the circumstances under which the robotic arm is controlled to stop moving. For example, the robotic arm can be controlled to stop moving after a set time.

[0054] To further ensure the safety of the procedure, optionally, such as Figure 3 As shown, the control method further includes: In step S140, when the force on the end of the surgical instrument reaches a second preset threshold, the robotic arm is controlled to stop moving.

[0055] As an optional implementation, the second set threshold can be consistent with a pre-configured initial traction force. It should be noted that under the action of the initial traction force, the surgical field of view can be ensured to be unobstructed by tissue. The first set threshold can be set by the operator, and the first set threshold is less than the second set threshold.

[0056] In this embodiment of the invention, there is no specific limitation on when to execute step S110. As an optional implementation, different working modes can be configured for the robotic arm. For example, the control mode of the robotic arm can be selected from at least one of the following modes, locking modes, and active modes.

[0057] In follow mode, the operator can move the surgical instruments to the required position by dragging the robotic arm; in locked mode, the position of the robotic arm remains unchanged; in active mode, the movement of the robotic arm can be controlled according to the above control method.

[0058] In other words, the control method further includes at least one of the following steps: Receive a mode switching signal, and in response to the mode switching signal, control the robotic arm to exit the current mode and enter the mode associated with the mode switching signal; Upon receiving a follow-up mode trigger signal, and in response to the follow-up mode trigger signal, release the position control of the robotic arm so that the robotic arm can move to the target position under the influence of an external dragging force. The lock mode trigger signal is received to keep the pose of the robotic arm unchanged.

[0059] Accordingly, the control method further includes: In step S100, an active mode trigger signal is received.

[0060] In response to the active mode trigger signal, the step of determining the magnitude and direction of the force applied to the end of the surgical instrument in real time is performed.

[0061] In this embodiment of the invention, no special limitations are placed on how mode triggering and mode switching are performed. For example, a control panel can be set on the robot, and the corresponding mode triggering signal or mode switching signal can be input through the control panel. Another example is that the mode triggering signal or mode switching signal can be input to the medical robot via voice control. Yet another example is that a foot switch can be set, and the mode triggering signal or mode switching signal can be input to the medical robot by controlling the foot switch.

[0062] As an optional implementation, the control method further includes: In response to a mode switching signal, the robotic arm is controlled to exit the active mode and enter the mode associated with the mode switching signal.

[0063] In other words, once a mode switching signal is received, the robotic arm exits the active mode, which can avoid misoperation and improve the user experience.

[0064] As a second aspect of the present invention, an electronic device is provided, wherein, as Figure 5 As shown, the electronic device includes: One or more processors 101; The memory 102 stores one or more computer programs that, when executed by the one or more processors 101, cause the one or more processors 101 to implement the control method provided according to the first aspect of the invention.

[0065] The electronic device may also include one or more I / O interfaces 103 connected between the processor 101 and the memory 102, configured to enable information interaction between the processor 101 and the memory 102.

[0066] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read-write interface) is connected between the processor and the memory, enabling information exchange between the processor and the memory, including but not limited to a data bus (Bus).

[0067] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the electronic device.

[0068] As a third aspect of the invention, such as Figure 6 As shown, a computer-readable medium is provided having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the control method according to the first aspect of the present invention.

[0069] As a fourth aspect of the present invention, a medical robot is provided, the medical robot including electronic equipment and at least one robotic arm for traction of tissues, the end joint of the robotic arm being used for mounting surgical instruments, wherein the electronic equipment is the electronic equipment provided in the second aspect of the present invention.

[0070] As mentioned above, during minimally invasive surgery, the movement of the robotic arm can be controlled by the force applied to the end of the surgical instrument, applying appropriate traction force to the tissue and maintaining a good surgical field of vision without increasing the surgeon's workload.

[0071] In this embodiment of the invention, the number of robotic arms in the medical robot is not specifically limited. For example, the medical robot includes four robotic arms, wherein one robotic arm is used to operate an endoscope, two robotic arms are used for tissue traction, and the last robotic arm is used for direct manipulation. In this embodiment of the invention, the control method is used to control the robotic arm used for traction. For example, the medical robot includes two robotic arms, wherein one robotic arm is used to operate an endoscope and the other robotic arm is used for tissue traction.

[0072] As described above, the medical robot also includes at least one three-dimensional force sensor, which is disposed on the end joint of the robotic arm to detect the force acting on the end joint of the robotic arm.

[0073] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. Accordingly, the computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can implement the methods of any of the above embodiments. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0074] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of the present invention will be included within the scope of the claims.

Claims

1. A control method for the robotic arm of a medical robot, characterized in that, The control method includes: The magnitude and direction of the force on the end of the surgical instrument are determined in real time, wherein the surgical instrument is mounted on the end joint of the robotic arm; When the force on the end of the surgical instrument is less than a first set threshold, the direction opposite to the direction of the force on the end of the surgical instrument is taken as the traction direction. The operating point of the surgical instrument is taken as the fixed point, and the rotation speed and direction of the end joint of the robotic arm about the fixed point, as well as the speed and direction of the axial translation of the end joint of the robotic arm relative to the fixed point are determined. The robotic arm is controlled to move according to the rotational speed and direction of the end joint of the robotic arm about the fixed point, and the speed and direction of the axial translation of the end joint of the robotic arm relative to the fixed point.

2. The control method according to claim 1, characterized in that, The step of determining the rotational speed and direction of the distal joint of the robotic arm about the fixed point, and the axial translational speed and direction of the distal joint of the robotic arm relative to the fixed point, using the direction opposite to the force applied to the distal end of the surgical instrument as the traction direction and the operating point of the surgical instrument as the fixed point, includes: Construct the Jacobian matrix based on the coordinates of the origin of the surgical instrument's coordinate system in the patient's coordinate system; The pulling direction is projected onto the motion space that satisfies the centroid constraint using the constructed Jacobian matrix to obtain a 6-dimensional target vector. In the target vector, the first 3 dimensions are the axial translational velocity of the end joint of the robotic arm relative to the fixed point, and the last 3 dimensions are the rotational velocity of the end joint of the robotic arm about the fixed point.

3. The control method according to claim 2, characterized in that, In the step of constructing the Jacobian matrix based on the coordinates Tool_P of the origin of the surgical instrument's coordinate system in the patient's coordinate system, the Jacobian matrix is ​​constructed using the following formula: J_rcm=[I3-Tool_P × ]; Where J_rcm is the Jacobian matrix; I3 is a third-order identity matrix; Tool_P × The oblique symmetric operator for the coordinates of Tool_P, the origin of the surgical instrument coordinate system, in the patient coordinate system.

4. The control method according to claim 1, characterized in that, The real-time determination of the magnitude and direction of the force acting on the tip of the surgical instrument includes: The magnitude and direction of the force acting on the end joint of the robotic arm are acquired in real time. Based on the installation method of the surgical instrument and the end joint of the robotic arm, as well as the length of the surgical instrument and the position of the operating point, calculate the magnitude and direction of the force on the end of the surgical instrument. Alternatively, data from a sensor installed at the end of the surgical instrument can be acquired in real time to determine the magnitude and direction of the force acting on the end of the surgical instrument.

5. The control method according to claim 1, characterized in that, The real-time determination of the magnitude and direction of the force acting on the tip of the surgical instrument includes: The force on the end joint of the robotic arm is detected by a three-dimensional force sensor installed on the end joint of the robotic arm; Calculate the force on the tip of the surgical instrument using the following formula: F_head =(Tool_P × Fext_P)× Tool_P / ||Head_P|| 2 ; Head_P = Tool_P - Tool_P / ||Tool_P|| * L; Fext_P = T_P_t * (-Fext_t_arm); Wherein, F_head is the force exerted on the end of the surgical instrument; Tool_P is the coordinate of the origin of the surgical instrument coordinate system in the patient coordinate system, where the fixed point is the origin of the patient coordinate system and the fulcrum for calculating the torque; Fext_P is the force applied to the surgical instrument by the end joint of the robotic arm in the patient coordinate system; Head_P is the coordinate of the end of the surgical instrument in the patient coordinate system; L is the length of the surgical instrument; T_P_t is the transformation matrix from the patient coordinate system to the surgical instrument coordinate system; Fext_t_arm is the force detected by the force sensor.

6. The control method according to any one of claims 1 to 5, characterized in that, The control method further includes: When the force on the end of the surgical instrument reaches a second preset threshold, the robotic arm is controlled to stop moving.

7. The control method according to any one of claims 1 to 5, characterized in that, The control method further includes: Receive active mode trigger signal; In response to the active mode trigger signal, the step of determining the magnitude and direction of the force applied to the end of the surgical instrument in real time is performed.

8. The control method according to claim 7, characterized in that, The control method further includes at least one of the following steps: Receive a mode switching signal, and in response to the mode switching signal, control the robotic arm to exit the current mode and enter the mode associated with the mode switching signal; Upon receiving a follow-up mode trigger signal, and in response to the follow-up mode trigger signal, release the position control of the robotic arm so that the robotic arm can move to the target position under the influence of an external dragging force. The lock mode trigger signal is received to keep the pose of the robotic arm unchanged.

9. An electronic device, characterized in that, include: One or more processors; A memory having stored one or more computer programs thereon, which, when executed by the one or more processors, cause the one or more processors to implement the control method according to any one of claims 1 to 8.

10. A computer-readable medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the control method according to any one of claims 1 to 8.

11. A medical robot, comprising electronic equipment and at least one robotic arm for retracting tissue, the distal joint of the robotic arm being used for mounting surgical instruments, characterized in that, The electronic device is the electronic device according to claim 9.

12. The medical robot according to claim 11, characterized in that, The medical robot also includes at least one three-dimensional force sensor, which is disposed on the end joint of the robotic arm to detect the force exerted on the end joint of the robotic arm.

Images