Surgical robotic system for overtravel adjustment based on jaw position

Abstract

A surgical robotic system includes an instrument drive unit having a plurality of motors, each motor including a torque sensor for measuring a torque of a corresponding motor of the plurality of motors and a position sensor for measuring a position of the corresponding motor of the plurality of motors. The system also includes an instrument coupled to the instrument drive unit. The instrument includes an end effector having a first jaw and a second jaw, a first cable coupled to the first jaw and actuatable by at least a first motor of the plurality of motors, and a second cable coupled to the second jaw and actuatable by at least a second motor of the plurality of motors, wherein the first cable and the second cable move the first jaw and the second jaw, respectively, between an open position and a closed position. The system further includes a controller to receive an input including an overtravel command indicating the plurality of motors to apply a force to the first jaw and the second jaw, calculate a desired angle between the first jaw and the second jaw based on at least the positions of the first motor and the second motor, compare the desired angle between the first jaw and the second jaw to a first threshold, and adjust the overtravel command if the desired angle between the first jaw and the second jaw is below the first threshold.

Description

Cross-reference to related applications

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 565,607, filed March 15, 2024, the entire contents of which are incorporated herein by reference. Background Technology

[0002] Surgical robotic systems are currently being used in a variety of surgical procedures, including minimally invasive surgery. Some surgical robotic systems include a surgeon's console that controls a robotic arm and surgical instruments with end effectors (e.g., clamps or gripping instruments) that are coupled to and actuated by the robotic arm. In operation, the robotic arm is moved to a position above the patient, and then the surgical instruments are guided through the patient's surgical port or natural orifice into a small incision to position the end effector at the working site within the patient's body.

[0003] Surgical robotic instruments can include various gripper-type instruments, such as grippers, vascular sealers, and shears. Instruments can be actuated by one or more cables used to open or close the grippers and to change their pitch and yaw directions. During gripper actuation, various parameters can be measured, which can be used to control the surgical instruments. Summary of the Invention

[0004] According to one embodiment of this disclosure, a surgical robot system is disclosed. The system includes an instrument drive unit having multiple motors, each motor including a torque sensor for measuring the torque of a corresponding motor among the multiple motors and a position sensor for measuring the position of a corresponding motor among the multiple motors. The system also includes an instrument coupled to the instrument drive unit. The instrument includes: an end effector having a first gripper and a second gripper; a first cable coupled to the first gripper and actuable by at least a first motor among the multiple motors; and a second cable coupled to the second gripper and actuable by at least a second motor among the multiple motors, wherein the first cable and the second cable respectively move the first gripper and the second gripper between an open position and a closed position. The system further includes a controller configured to: receive an input including an overtravel command instructing a plurality of motors to apply force to a first gripper and a second gripper; calculate a desired angle between the first gripper and the second gripper based on the measured position of each of the plurality of motors; compare the desired angle between the first gripper and the second gripper with a first threshold; and adjust the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold.

[0005] Implementations of the above embodiments may include one or more of the following features. According to one aspect of the above embodiments, the controller may further calculate the derivative of a desired angle between the first and second grippers. The controller may further calculate the absolute value of the derivative of the desired angle between the first and second grippers. The controller may also compare the absolute value of the derivative of the desired angle between the first and second grippers with a second threshold. If the desired angle between the first and second grippers is lower than a first threshold and the absolute value of the derivative of the desired angle between the first and second grippers is lower than a second threshold, the controller may additionally determine whether to adjust an overtravel command. The end effector may be a shear, and each of the first and second grippers may include a blade. The controller may also calculate a force for the overtravel command based on the desired angle between the first and second grippers. The controller may additionally use a scaling factor selected based on the desired angle between the first and second grippers to adjust the force for the overtravel command. The controller may further detect an overtorque condition based on a measured torque exceeding a torque threshold for any of the plurality of motors.

[0006] According to another embodiment of this disclosure, a surgical robot system is disclosed. The surgical robot system includes a plurality of motors, each motor including a torque sensor for measuring the torque of a corresponding motor among the plurality of motors and a position sensor for measuring the position of a corresponding motor among the plurality of motors. The system also includes an instrument having: a shear end effector having a first blade and a second blade; a first cable coupled to the first blade and actuable by a first motor among the plurality of motors; and a second cable coupled to the second blade and actuable by at least a second motor among the plurality of motors, wherein the first cable and the second cable respectively move the first blade and the second blade from an open position to a closed position. The system further includes a controller configured to: receive an input including an overtravel command instructing the plurality of motors to apply force to the first blade and the second blade; calculate a desired angle between the first blade and the second blade based on the measured position of each motor among the plurality of motors; compare the desired angle between the first blade and the second blade with the first threshold; and adjust the overtravel command if the desired angle between the first blade and the second blade is lower than the first threshold.

[0007] The implementation of the above embodiments may include one or more of the following features. According to one aspect of the above embodiments, the controller may further calculate the derivative of the desired angle between the first blade and the second blade. The controller may further calculate the absolute value of the derivative of the desired angle between the first blade and the second blade. The controller may also compare the absolute value of the derivative of the desired angle between the first blade and the second blade with a second threshold. If the desired angle between the first blade and the second blade is lower than the first threshold and the absolute value of the derivative of the desired angle between the first blade and the second blade is lower than the second threshold, the controller may additionally determine whether to adjust the overtravel command. The controller may also calculate the force for the overtravel command based on the desired angle between the first blade and the second blade. The controller may also adjust the force for the overtravel command using a scaling factor selected based on the desired angle between the first blade and the second blade. The controller may further detect an over-torque condition based on the measured torque of any of the plurality of motors exceeding a torque threshold.

[0008] According to another embodiment of this disclosure, a method for controlling a surgical robot instrument is disclosed. The method includes moving a first gripper and a second gripper from an open position to a closed position, wherein the first gripper is coupled to a first cable actuated by a first motor, and the second gripper is coupled to a second cable actuated by a second motor. The method further includes measuring the angular positions of the first motor and the second motor. The method further includes receiving an input including an overtravel command instructing the first motor and the second motor to apply forces to the first gripper and the second gripper; and calculating a desired angle between the first gripper and the second gripper, at least based on the measured angular positions of the first motor and the second motor. The method additionally includes comparing the desired angle between the first gripper and the second gripper with the first threshold, and adjusting the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold.

[0009] The implementation of the above embodiments may include one or more of the following features. According to one aspect of the above embodiments, the method may further include calculating the derivative of a desired angle between the first gripper and the second gripper, and calculating the absolute value of the derivative of the desired angle between the first gripper and the second gripper. The method may further include comparing the absolute value of the derivative of the desired angle between the first gripper and the second gripper with a second threshold, and if the desired angle between the first gripper and the second gripper is lower than a first threshold and the absolute value of the derivative of the desired angle between the first gripper and the second gripper is lower than a second threshold, then determining whether to adjust the overtravel command. Attached Figure Description

[0010] Different embodiments of the disclosure are described herein with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of a surgical robot system according to an embodiment of the present disclosure, the surgical robot system including a control tower, a console, and one or more surgical robotic arms, all mounted on a movable trolley; Figure 2 Examples based on this disclosure Figure 1 A 3D view of the surgical robotic arm of a surgical robot system; Figure 3 This is a perspective view of a movable trolley with a mounting arm according to an embodiment of the present disclosure, the mounting arm having... Figure 1 Surgical robotic arms in surgical robot systems; Figure 4 Examples based on this disclosure Figure 1 A schematic diagram of the computer architecture of a surgical robot system; Figure 5 This is based on the aspects of the disclosure regarding the positioning of the operating table. Figure 1 A plan view of the movable cart; Figure 6 This is a perspective view of an instrument drive unit and surgical instruments according to embodiments of this disclosure, wherein the components are separate; Figure 7 It is an embodiment of the present disclosure for use Figure 1 Top-view perspective of the end effector of the gripper in a surgical robot system; Figure 8 It is an embodiment of the present disclosure for use Figure 1 Top-view perspective of the shearing end effector in a surgical robot system; Figure 9 End effectors in different configurations according to embodiments of this disclosure are shown; and Figure 10 This is a flowchart of an overtravel adjustment method based on gripper position according to an embodiment of the present disclosure. Detailed Implementation

[0011] Embodiments of the surgical robot system disclosed herein are described in detail with reference to the accompanying drawings, in which the same reference numerals denote the same or corresponding elements in each of several views.

[0012] As will be described in detail below, this disclosure relates to a surgical robot system including a surgeon's console, a control tower, and one or more mobile trolleys having a surgical robotic arm coupled to an attachment arm. The surgeon's console receives user input via one or more interface devices. This input is processed by the control tower as movement commands for moving the surgical robotic arm and attached instruments and / or cameras. Therefore, the surgeon's console enables remote operation of the surgical arm and attached instruments / cameras. The surgical robotic arm includes a controller configured to process the movement commands and generate torque commands for activating one or more actuators of the robotic arm, which in turn move the robotic arm in response to the movement commands.

[0013] refer to Figure 1 The surgical robot system 10 includes a control tower 20 connected to all components of the surgical robot system 10, including a surgeon's console 30 and one or more movable trolleys 60. Each movable trolley 60 includes a robotic arm 40 with surgical instruments 50 attached thereto. The robotic arm 40 is also coupled to the movable trolley 60. The robot system 10 may include any number of movable trolleys 60 and / or any number of robotic arms 40.

[0014] Surgical instrument 50 is configured for use during minimally invasive surgical procedures. In one embodiment, surgical instrument 50 may be configured for open surgical procedures. In another embodiment, surgical instrument 50 may be an electrosurgical clamp configured to seal tissue by pressing tissue between clamping jaw members and applying an electrosurgical current to the tissue. In yet another embodiment, surgical instrument 50 may be a surgical stapler including a pair of jaws configured to clamp and hold tissue, simultaneously deploying multiple tissue fasteners (e.g., staples) and cutting the stapled tissue. In yet another embodiment, surgical instrument 50 may be a surgical clip applicator including a pair of jaws configured to apply a surgical clip to tissue. However, it should be understood that various types of surgical instruments are contemplated for use during minimally invasive surgical procedures, and such surgical instruments are within the scope of this disclosure.

[0015] One of the robotic arms 40 may include an endoscope camera 51 configured to capture video of the surgical site. The endoscope camera 51 may be a stereoscopic endoscope configured to capture two side-by-side (i.e., left and right) images of the surgical site to generate a video stream of the surgical scene. The endoscope camera 51 is coupled to a video processing unit 56, which may be located within the control tower 20. The video processing unit 56 may be any computing device as described below, configured to receive video feeds from the endoscope camera 51 and output a processed video stream.

[0016] The surgeon's console 30 includes a first display 32 and a second display 34. The first display shows a video feed of the surgical site provided by a camera 51 mounted on the robotic arm 40, and the second display shows a user interface for controlling the surgical robot system 10. The first display 32 and the second display 34 may be touchscreens that allow for the display of various graphical user inputs.

[0017] The surgeon's console 30 also includes several user interface devices, such as a foot pedal 36 and a pair of handle controllers 38a and 38b, which the user uses to remotely control the robotic arm 40. The surgeon's console further includes a handrail 33 for supporting the clinician's arm when operating the handle controllers 38a and 38b.

[0018] The control tower 20 includes a display 23 (which may be a touchscreen) capable of displaying a graphical user interface (GUI). The control tower 20 also serves as an interface between the surgeon's console 30 and one or more robotic arms 40. Specifically, the control tower 20 is configured to control the robotic arms 40 based on a set of programmable instructions and / or input commands from the surgeon's console 30, to move the robotic arms 40 and corresponding surgical instruments 50 in such a way that the robotic arms 40 and surgical instruments 50 perform a desired sequence of movements in response to inputs from foot pedals 36 and handpiece controllers 38a and 38b. Foot pedals 36 can be used to enable and lock handpiece controllers 38a and 38b, reposition camera movement, and activate / deactivate electrosurgical devices. Specifically, foot pedals 36 can be used to perform clutch actions on handpiece controllers 38a and 38b. Engaging the clutch by pressing one of the foot pedals 36 disconnects the handpiece controllers 38a and / or 38b from the robotic arms 40 and their attached corresponding instruments 50 or cameras 51 (i.e., prevents movement input). This allows the user to reposition the handle controllers 38a and 38b without moving the robotic arm 40, as well as the instrument 50 and / or camera 51. This is useful when reaching the control boundaries of the surgical space.

[0019] Each of the control tower 20, the surgeon's console 30, and the robotic arm 40 includes a corresponding computer 21, 31, or 41. Computers 21, 31, and 41 are interconnected using any suitable communication network based on wired or wireless communication protocols. As used herein, the term "network," whether plural or singular, means a data network, including but not limited to the Internet, intranet, wide area network, or local area network, and is not limited to the full scope of the definition of communication networks covered by this disclosure. Suitable protocols include, but are not limited to, Transmission Control Protocol / Internet Protocol (TCP / IP), Datagram Protocol / Internet Protocol (UDP / IP), and / or Datagram Congestion Control Protocol (DCCP). Wireless communication can be achieved via one or more wireless configurations, such as radio frequency, optical, Wi-Fi, Bluetooth (an open wireless protocol used to exchange data between fixed and mobile devices over short distances using short-wavelength radio waves to create personal area networks (PANs)), and ZigBee® (a set of specifications for advanced communication protocols using small, low-power digital radios based on the IEEE 122.15.4-1203 Wireless Personal Area Network (WPAN) standard).

[0020] Computers 21, 31, and 41 may include any suitable processor (not shown) operatively connected to a memory (not shown) that may include one or more of volatile, non-volatile, magnetic, optical, or electrical media, such as read-only memory (ROM), random access memory (RAM), electrically erasable programmable ROM (EEPROM), non-volatile RAM (NVRAM), or flash memory. The processor may be any suitable processor (e.g., control circuitry) adapted to perform the operations, calculations, and / or instruction sets described in this disclosure, including but not limited to hardware processors, field-programmable gate arrays (FPGAs), digital signal processors (DSPs), central processing units (CPUs), microprocessors, and combinations thereof. Those skilled in the art will understand that a processor may be used instead of a logic processor (e.g., control circuitry) adapted to perform the algorithms, calculations, and / or instruction sets described herein.

[0021] refer to Figure 2 Each robotic arm 40 may include a plurality of links 42a, 42b, 42c, which are interconnected at joints 44a, 44b, 44c, respectively. Other configurations of links and joints may be used, as is known to those skilled in the art. Joint 44a is configured to secure the robotic arm 40 to a movable trolley 60 and define a first longitudinal axis. (Reference) Figure 3The movable trolley 60 includes a lift 67 and a mounting arm 61, which provides a base for mounting the robotic arm 40. The lift 67 allows the mounting arm 61 to move vertically. The movable trolley 60 also includes a display 69 for displaying information about the robotic arm 40. In embodiments, the robotic arm 40 may include any type and / or any number of joints.

[0022] The mounting arm 61 includes a first link 62a, a second link 62b, and a third link 62c, which provide lateral maneuverability of the robotic arm 40. Links 62a, 62b, and 62c are interconnected at joints 63a and 63b, each joint including an actuator (not shown) for rotating links 62b and 62b relative to each other and relative to link 62c. Specifically, links 62a, 62b, and 62c are movable in their corresponding parallel lateral planes, thereby allowing the robotic arm 40 to extend relative to a patient (e.g., an operating table). In an embodiment, the robotic arm 40 may be coupled to an operating table (not shown). The mounting arm 61 includes controls 65 for adjusting the movement of links 62a, 62b, and 62c, as well as the lift 67. In an embodiment, the mounting arm 61 may include any type and / or any number of joints.

[0023] The third link 62c may include a rotatable base 64 having two degrees of freedom. Specifically, the rotatable base 64 includes a first actuator 64a and a second actuator 64b. The first actuator 64a is rotatable about a first fixed arm axis perpendicular to the plane defined by the third link 62c, and the second actuator 64b is rotatable about a second fixed arm axis transverse to the first fixed arm axis. The first actuator 64a and the second actuator 64b allow for full three-dimensional orientation of the robotic arm 40.

[0024] Actuator 48b of joint 44b is coupled to joint 44c via belt 45a, and joint 44c is further coupled to joint 46b via belt 45b. Joint 44c may include a transfer case connecting belts 45a and 45b, such that actuator 48b is configured to rotate each of links 42b, 42c and retainer 46 relative to each other. More specifically, links 42b, 42c and retainer 46 are passively coupled to actuator 48b, which forces rotation about a pivot point “P” located at the intersection of a first axis defined by link 42a and a second axis defined by retainer 46. In other words, pivot point “P” is the remote center of motion (RCM) of robotic arm 40. Thus, actuator 48b controls the angle θ between the first and second axes, thereby allowing orientation of surgical instrument 50. Because links 42a, 42b, 42c and retainer 46 are interconnected via belts 45a and 45b, the angle between links 42a, 42b, 42c and retainer 46 is also adjusted to achieve a desired angle θ. In an embodiment, some or all of joints 44a, 44b, 44c may include actuators to eliminate the need for mechanical linkages.

[0025] Joints 44a and 44b include actuators 48a and 48b configured to drive joints 44a, 44b, and 44c relative to each other via a series of links 45a and 45b or other mechanical linkages (such as drive rods, cables, or levers). Specifically, actuator 48a is configured to rotate the robotic arm 40 about a longitudinal axis defined by link 42a.

[0026] refer to Figure 2 The retainer 46 defines a second longitudinal axis and is configured to receive the instrument drive unit (IDU) 52. Figure 1 IDU 52 is configured as an actuation mechanism coupled to surgical instrument 50 and camera 51 and is configured to move (e.g., rotate) and actuate instrument 50 and / or camera 51. IDU 52 transmits actuating force from its actuator to surgical instrument 50 to actuate components of end effector 49 of surgical instrument 50. Holder 46 includes sliding mechanism 46a configured to move IDU 52 along a second longitudinal axis defined by holder 46. Holder 46 also includes joint 46b that rotates holder 46 relative to link 42c. During endoscopic surgery, instrument 50 can pass through endoscope access port 55 held by holder 46. Figure 3 Insertion. The retainer 46 also includes a port latch 46c for securing the inlet port 55 to the retainer 46. Figure 2 ).

[0027] IDU 52 is attached to retainer 46, and then a sterile interface module (SIM) 43 is attached to the distal portion of IDU 52. SIM 43 is configured to secure a sterile drape (not shown) to IDU 52. Instrument 50 is then attached to SIM 43. Instrument 50 is then inserted through inlet port 55 by moving IDU 52 along retainer 46. SIM 43 includes multiple drive shafts configured to transmit rotation of individual motors of IDU 52 to instrument 50, thereby actuating instrument 50. Furthermore, SIM 43 provides a sterile barrier between instrument 50 and other components of robotic arm 40, including IDU 52.

[0028] The robotic arm 40 also includes a mounting arm 61 and multiple manual control buttons 53 mounted on the IDU 52. Figure 1 The mounting arm can be used in manual mode. The user can press one or more of these buttons 53 to move the component associated with the one or more buttons 53.

[0029] refer to Figure 4 Each of the computers 21, 31, and 41 in the surgical robot system 10 may include multiple controllers, which may be implemented in hardware and / or software. The computer 21 of the control tower 20 includes a controller 21a and a safety observer 21b. The controller 21a receives data from the computer 31 of the surgeon's console 30 regarding the current position and / or orientation of the handle controllers 38a and 38b, as well as the status of the foot pedals 36 and other buttons. The controller 21a processes these input positions to determine the desired drive commands for each joint of the robotic arm 40 and / or the IDU 52, and transmits these desired drive commands to the computer 41 of the robotic arm 40. The controller 21a also receives the actual joint angles measured by the encoders of the actuators 48a and 48b and uses this information to determine force feedback commands, which are transmitted back to the computer 31 of the surgeon's console 30 to provide tactile feedback via the handle controllers 38a and 38b. The safety observer 21b performs validity checks on the data entering and exiting the controller 21a, and if an error is detected in the data transmission, it notifies the system fault handler to put the computer 21 and / or the surgical robot system 10 into a safe state.

[0030] Computer 41 includes multiple controllers: a trolley main controller 41a, a mounting arm controller 41b, a robotic arm controller 41c, and an instrument drive unit (IDU) controller 41d. The trolley main controller 41a receives and processes joint commands from controller 21a on computer 21 and transmits them to the mounting arm controller 41b, robotic arm controller 41c, and IDU controller 41d. The trolley main controller 41a also manages instrument exchange and the overall status of the movable trolley 60, robotic arm 40, and IDU 52. The trolley main controller 41a also transmits actual joint angles back to controller 21a.

[0031] Each of joints 63a and 63b, and the rotatable base 64 of the mounting arm 61, is a passive joint that allows manual adjustment by the user (i.e., where no actuator is present). Joints 63a and 63b, and the rotatable base 64, include brakes that are disengaged by the user to configure the mounting arm 61. When the brakes are engaged, the mounting arm controller 41b monitors slippage of each of joints 63a and 63b of the mounting arm 61 and the rotatable base 64, or when the brakes are disengaged, the operator is free to move the mounting arm controller without affecting control of other joints. The robotic arm controller 41c controls each joint 44a and 44b of the robotic arm 40 and calculates the desired motor torque required for gravity compensation, friction compensation, and closed-loop position control of the robotic arm 40. The robotic arm controller 41c calculates movement commands based on the calculated torques. The calculated motor commands are then transmitted to one or more of the actuators 48a and 48b in the robotic arm 40. The actual joint position is then transmitted back to the robotic arm controller 41c by actuators 48a and 48b.

[0032] IDU controller 41d receives the desired joint angles (such as wrist angle and gripper angle) from surgical instrument 50 and calculates the desired current of the motor in IDU 52. IDU controller 41d calculates the actual angles based on the motor position and transmits these actual angles back to trolley main controller 41a.

[0033] The robotic arm 40 is controlled in response to the posture of a handle controller (e.g., handle controller 38a) that controls the robotic arm 40, the posture being transformed into the desired posture of the robotic arm 40 via a hand-eye transformation function performed by controller 21a. The hand-eye function, as well as other functions described herein, is implemented in software executable by controller 21a or any other suitable controller described herein. The posture of one of the handle controllers 38a can be implemented as a coordinate position and roll-pitch-yaw (RPY) orientation relative to a coordinate reference system fixed to the surgeon's console 30. The desired posture of the instrument 50 is relative to a fixation system on the robotic arm 40. The posture of the handle controller 38a is then scaled by a scaling function performed by controller 21a. In an embodiment, the scaling function can reduce the coordinate position and enlarge the orientation. Additionally, controller 21a can also perform a clutch function to disengage the handle controller 38a from the robotic arm 40. Specifically, if certain movement limits or other thresholds are exceeded, controller 21a stops transmitting movement commands from handle controller 38a to robotic arm 40, and essentially acts like a virtual clutch mechanism, for example, limiting the mechanical input from affecting the mechanical output.

[0034] The desired posture of the robotic arm 40 is based on the posture of the handle controller 38a and then transmitted via an inverse kinematics function executed by the controller 21a. The inverse kinematics function calculates the angles of the joints 44a, 44b, and 44c of the robotic arm 40, realizing the scaled and adjusted posture input from the handle controller 38a. The desired angles are then transmitted to the robotic arm controller 41c, which includes a joint axis controller with a proportional-derivative (PD) controller, a friction estimator module, a gravity compensator module, and a double-sided saturation block configured to limit the command torque of the motors of joints 44a, 44b, and 44c. In various respects, the handle controller 38a can be replaced by and / or used in conjunction with the handle controller 38b. While reference has been made to the handle controller 38a above, the handle controller 38b can also be used in a similar manner.

[0035] refer to Figure 5 The surgical robot system 10 is positioned around the operating table 90. System 10 includes movable trolleys 60a-d, which can be numbered "1" to "4". During setup, each of the trolleys 60a-d is positioned around the operating table 90. The position and orientation of the trolleys 60a-d depend on several factors, such as the placement of multiple access ports 55a-d, which in turn depend on the surgery being performed. Once the port placement is determined, the access ports 55a-d are inserted into the patient, and the trolleys 60a-d are positioned to insert instruments 50 and an endoscope camera 51 into their corresponding ports 55a-d.

[0036] During use, each of the robotic arms 40a-d uses lock 46c ( Figure 2 ) Attached to inlet port 55 ( Figure 3 The IDU 52 is attached to one of the entry ports 55a-d that are inserted into the patient's body. The IDU 52 is attached to the retainer 46, and then the SIM 43 is attached to the distal portion of the IDU 52. The device 50 is then attached to the SIM 43. The device 50 is then inserted through the entry port 55 by moving the IDU 52 along the retainer 46.

[0037] refer to Figure 6 IDU 52 is shown in more detail and configured to transmit power and actuation from its motors 152a, 152b, 152c, 152d to instrument 50 to drive the movement of components of instrument 50, such as articulation, rotation, pitch, lateral oscillation, clamping, cutting, etc. IDU 52 can also be configured to activate or fire instruments based on electrosurgical energy (e.g., cable actuators, pulleys, friction wheels, rack and pinion arrangements, etc.).

[0038] IDU 52 includes a motor assembly 150 and a sterile barrier housing 130. The motor assembly 150 includes motors 152a, 152b, 152c, and 152d for controlling various operations of the device 50. The device 50 is removably coupled to the IDU 52. When the motors 152a, 152b, 152c, and 152d of the motor assembly 150 are actuated, rotation of the drive transmission shafts 154a, 154b, 154c, and 154d of the motors 152a, 152b, 152c, and 152d is transmitted to the drive assembly of the device 50. The device 50 is configured to convert rotational force / movement supplied by the IDU 52 (e.g., via the motors 152a, 152b, 152c, and 152d of the motor assembly 150) into longitudinal or translational movement of cables or drive shafts to achieve end effector 200 or 200' (…). Figure 7 and Figure 8 (various functions) Figure 7 The gripper end effector 200 is shown, and Figure 8 The shear end effector 200' is shown; for simplicity, the operation of IDU 52 is described with reference only to end effector 200'. End effector 200' is used in conjunction with... Figure 7 and Figure 9 The gripper end effector 200 operates in a basically similar manner, but the grippers 120 and 122 are replaced by blade members 120' and 122'.

[0039] Each of motors 152a, 152b, 152c, and 152d includes a current sensor 153, a torque sensor 155, and a position sensor 157. For simplicity, only the operation of motor 152a is described below; however, it should be understood that motors 152b-d can operate in a similar manner. Sensors 153, 155, and 157 monitor the performance of motor 152a. Current sensor 153 is configured to measure the current consumption of motor 152a, and torque sensor 155 is configured to measure motor torque. Torque sensor 155 can be any force or strain sensor including one or more strain gauges configured to convert mechanical force and / or strain into a sensor signal indicating the torque output by motor 152a. Position sensor 157 can be any device that provides a sensor signal indicating the number of revolutions of motor 152a, such as a mechanical encoder or an optical encoder. Parameters measured and / or determined by position sensor 157 can include speed, distance, revolutions per minute, position, etc. Sensor signals from sensors 153, 155, and 157 are transmitted to IDU controller 41d, which then controls motors 152a, 152b, 152c, and 152d based on the sensor signals. Specifically, motors 152a, 152b, 152c, and 152d are controlled by actuator controller 159, which controls the output torque and angular velocity of motors 152a, 152b, 152c, and 152d. In embodiments, additional position sensors may also be used, including but not limited to potentiometers, Hall effect sensors, accelerometers, and gyroscopes coupled to the movable part and configured to detect travel distance. In embodiments, a single controller may perform the functions of both IDU controller 41d and actuator controller 159.

[0040] refer to Figure 6 The device 50 includes an adapter 160 having a housing 162 at its proximal portion and an elongated shaft 164 extending distally from the housing 162. The housing 162 of the device 50 is configured to selectively connect to an IDU 52, enabling motors 152a, 152b, 152c, 152d of the IDU 52 to operate the end effector 200 of the device 50. The housing 162 of the device 50 supports a drive assembly that mechanically and / or electrically cooperates with the motors 152a, 152b, 152c, 152d of the IDU 52. The drive assembly of the device 50 may include any suitable electrical and / or mechanical components to achieve driving force / movement.

[0041] The surgical instrument also includes an end effector 200 coupled to the elongated shaft 164. The end effector 200 may include any number of degrees of freedom that allow the end effector 200 to articulate, pivot, etc., relative to the elongated shaft 164. The end effector 200 may be any suitable surgical end effector configured to treat tissue, such as a dissecter, gripper, sealer, stapler, etc.

[0042] like Figure 7 and Figure 9 As shown, the end effector 200 may include a pair of opposing grippers 120 and 122 movable relative to each other. In an embodiment, the end effector 200 may include a proximal portion 112 and a distal portion 114 having a first pin 113. Although grippers 120 and 122 are shown as clamping grippers, it should be understood that the grippers can be any suitable type of gripper, such as a shear, etc. The end effector 200 may be actuated using multiple cables 201a-d, which are routed around their respective pulleys 112a, 112b, 114a, 114b through the proximal portion 112 and the distal portion 114, the pulleys being integrally formed as arms of the proximal and distal portions 112 and 114. Each of the cables 201a-d is actuated by a corresponding motor 152a-d via a corresponding connector disposed in an adapter 160. In one embodiment, the end effector 200 (i.e., the distal portion 114 and the grippers 120 and 122) can be articulated about axis “AA” to control the yaw angle of the end effector relative to the longitudinal axis “XX”. The distal portion 114 includes a second pin 115 to which a pair of grippers, the first gripper 120 and the second gripper 122, are pivotally coupled. The grippers 120 and 122 are configured to pivot about axis “BB” defined by the second pin 115, thereby allowing control of the pitch angle of the grippers 120 and 122, as well as the opening and closing of the grippers 120 and 122. As the grippers 120 and 122 move between an open position and a closed position, by adjusting… Figure 8 The tension and / or length and orientation (e.g., proximal or distal) of the cables 201a-d shown are used to control the yaw, pitch, and gripper angle between the grippers. The end effector 200 also includes a cable displacement sensor 116 configured to measure the position of the cable 201. Therefore, the end effector 200 can have three degrees of freedom: yaw, pitch, and gripper angle between grippers 120 and 122.

[0043] The wrist-type end effector 200 utilizes drive cables 201a-d to articulate pitch, yaw, and gripper degrees of freedom. The cables responsible for closing the gripper are referred to as high-side cables 201b and 201c, and the cables responsible for opening the gripper are referred to as low-side cables 201a and 201d. Therefore, high-side cables 201c and low-side cables 201a actuate the second gripper 122, and high-side cables 201b and low-side cables 201d actuate the first gripper 120. During closure, high-side cables 201b and 201c are tensioned, while minimum tension is applied to low-side cables 201a and 201d. During opening, tension is applied in the opposite direction to the cables; that is, higher tension is applied to low-side cables 201a and 201d, and minimum tension is applied to high-side cables 201b and 201c. Cables 201a-d are controlled by their respective motors 152a-d. Therefore, motors 152b and 152c are high-side motors because they actuate high-side cables 201b and 201c, and motors 152a and 152d are low-side motors because they actuate low-side cables 201a and 201d.

[0044] During actuation of end effector 200 or end effector 200', IDU controller 41d continuously monitors the torque and angular position of each of motors 152a-d. IDU controller 41d also continuously compares the measured torque of each of motors 152a-d with a torque threshold indicating over-torque, which can be approximately 0.65 Nm. If an over-torque condition is detected, IDU controller 41d can stop operation of all motors 152a-d to avoid damage to instrument 50 and / or tissue. In some cases, this over-torque protection may generate false alarms.

[0045] This disclosure provides a system and method for detecting and avoiding overtorque that may occur when blade members 120' and 122' are partially closed (i.e., not fully closed), then paused, and then commanded to fully close (i.e., 0º closure angle). Specifically, the overtorque is detected after blade members 120' and 122' have been moved to the fully closed position in response to an overtravel command. The overtravel function is used to command blade members 120' and 122' to ensure that tissue or object is completely cut, rather than simply closing blade members 120' and 122' to the fully closed position. Therefore, the overtravel command involves outputting excessive torque via motors 152a-d to not only close blade members 120' and 122', but to close the blade members with excessive force to cut the object.

[0046] The reason for performing over-torque detection is that the overtravel generated by some small actuation events is as large as that generated by a fully closed event. In a fully closed event, there is sufficient time for the overtravel to be consumed by the friction of the blades of blade members 120' and 122'. However, in small actuation events where the blade members are mostly closed, there is not enough time to fully consume the generated overtravel force. Therefore, when the gripper is fully closed, the remaining portion of the overtravel force is applied to the cable. This results in excessive tension in cables 201a-d, and is therefore measured as excessive torque sensor readings. The method used to operate the overtravel command in this situation is to reduce the overtravel force of the smaller or partially closed event by using a scaling function.

[0047] The scaling function applies to both small closure events and partial closure events. Small closure events begin at zero angle, where blade members 120' and 122' are fully closed, continue opening to a small angle, and then return to zero angle. Partial closure events are those that begin at 100% opening with blade members 120' and 122' fully open, continue closing to a small angle (e.g., less than 10º), and then continue closing to zero angle after a pause. The scaling algorithm detects pauses or changes in direction and initiates the overtravel function's reduction. Therefore, the overtravel function is tailored to the opening degree (i.e., gripper angle) of blade members 120' and 122'.

[0048] refer to Figure 10 An illustrative method for adjusting the overtravel function in a blade-type end effector is implemented as software instructions executable by any suitable processor of the robot system 10, such as IDU controller 41d, main controller 21a, etc. This method is executed in response to an overtravel command, which can be executed by IDU controller 41d in response to a user's input for a complete closure or cut to cut an object (e.g., tissue, suture, etc.) provided via handle controllers 38a or 38b.

[0049] The motor position and torque of each motor 152a-d are provided to the controller 41d. Specifically, torque sensor 155 provides torque measurement, and position sensor 157 provides the angular rotational position of each of the motors 152a-d. The controller 41d then uses the angular position to determine the position of cables 201a-d and end effector 200. Torque is used to determine whether an overtorque condition has occurred. The IDU controller 41d compares the measured torque of each of the motors 152a-d with a torque threshold indicating overtorque. The overtorque comparison can be performed periodically at a current rate of approximately 10 Hz, and the comparison value can be approximately 0.65 Nm.

[0050] At step 400, the gripper position, such as the desired angle between blade members 120' and 122', is calculated based on the angular position data provided by the position sensor 157 of motors 152a-d. The desired gripper angle corresponds to the angle input by the user.

[0051] At step 402, the gripper position is compared with a first threshold (i.e., the gripper position threshold). If the gripper position is less than the first threshold, the IDU controller 41d outputs a true value. At step 404, the desired gripper angle is further processed by taking the derivative of the desired gripper angle. At step 406, the absolute value of the derivative of the gripper position is calculated. Then, at step 408, the absolute value of the derivative of the gripper position is compared with a second threshold (i.e., the absolute value threshold of the derivative of the gripper position). If the processed gripper position value is less than the second threshold, the IDU controller 41d outputs a true value; otherwise, the controller 41d outputs a false value.

[0052] At step 410, the controller receives the outputs from the gripper position determination in steps 406 and 408 as inputs and performs a bitwise AND operation on these inputs. Therefore, if the output of step 410 is negative, i.e., one or both values ​​in steps 406 and 408 are false, indicating that blade members 120' and 122' are open beyond the low opening degree, the method proceeds to step 412. If both values ​​are true, i.e., the gripper position is below the first and second thresholds, indicating that blade members 120' and 122' are open at or below the low opening degree, the method proceeds to step 414.

[0053] At step 412, the IDU controller 41d calculates an overtravel command to use a full overtravel force, which may be stored as a value in memory. At step 414, the IDU controller 41d adjusts the overtravel command. The IDU controller 41d calculates a modified overtravel force used when blade members 120' and 122' are opened to a low opening degree. The overtravel force is calculated using a scaling factor, which may include multiplying the full overtravel force by the scaling factor. The scaling factor corresponds to the opening degree of blade members 120' and 122' and is then used to adjust the overtravel force accordingly. The scaling factor may be stored in memory (e.g., a lookup table) and looked up by the IDU controller 41d based on the opening degree of blade members 120' and 122', or calculated by the IDU controller 41d using a transfer function based on the opening degree of blade members 120' and 122'.

[0054] At step 416, the IDU controller 41d executes an overtravel command, either the full force command from step 412 or the adjusted force command from step 414. Motors 152a-d are commanded to actuate blade members 120' and 122' into overtravel movement based on the overtravel force. Thereafter, the method returns to step 400 to continue monitoring the overtorque and the corresponding overtravel force. Although Figure 10 The method described is for blade-type end effectors, but overtravel commands can be used for various other gripper-type end effectors, such as... Figure 7 and Figure 9 The end effector 200 of the gripper, the end effector of the suture, the vascular sealer, etc. In this case, the overtravel command can be used to apply excessive torque through the motors 152a-d to apply additional pressure to the object (e.g., tissue) held by the end effector.

[0055] It should be understood that various modifications can be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but rather as illustrative of the various embodiments only. Other modifications will be contemplated by those skilled in the art within the scope and spirit of the appended claims.

[0056] The following examples illustrate the techniques described in this article.

[0057] Example 1. A surgical robot system, comprising: an instrument drive unit, the instrument drive unit including: a plurality of motors, each of the plurality of motors including a torque sensor for measuring the torque of a corresponding motor among the plurality of motors and a position sensor for measuring the position of a corresponding motor among the plurality of motors; an instrument coupled to the instrument drive unit, the instrument including: an end effector having a first gripper and a second gripper; a first cable coupled to the first gripper and actuable by at least a first motor among the plurality of motors; and a second cable coupled to the second gripper and actuable by at least a first motor among the plurality of motors. The system includes a second motor actuation, wherein the first cable and the second cable respectively move the first gripper and the second gripper between an open position and a closed position; and a controller configured to: receive an input including an overtravel command instructing the plurality of motors to apply force to the first gripper and the second gripper; calculate a desired angle between the first gripper and the second gripper based on the measured position of each of the plurality of motors; compare the desired angle between the first gripper and the second gripper with a first threshold; and adjust the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold.

[0058] Example 2. The surgical robot system according to Example 1, wherein the controller is further configured to calculate the derivative of the desired angle between the first gripper and the second gripper.

[0059] Example 3. The surgical robot system according to Example 2, wherein the controller is further configured to calculate the absolute value of the derivative of the desired angle between the first gripper and the second gripper.

[0060] Example 4. The surgical robot system according to Example 3, wherein the controller is further configured to compare the absolute value of the derivative of the desired angle between the first gripper and the second gripper with a second threshold.

[0061] Example 5. The surgical robot system according to Example 4, wherein the controller is further configured to determine whether to adjust the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold and the absolute value of the derivative of the desired angle between the first gripper and the second gripper is lower than the second threshold.

[0062] Example 6. The surgical robot system according to Example 1, wherein the end effector is a shear, and each of the first gripper and the second gripper includes a blade.

[0063] Example 7. The surgical robot system according to Example 1, wherein the controller is further configured to calculate the force for the overtravel command based on the desired angle between the first gripper and the second gripper.

[0064] Example 8. The surgical robot system according to Example 7, wherein the controller is further configured to adjust the force for the overtravel command using a scaling factor selected based on the desired angle between the first gripper and the second gripper.

[0065] Example 9. The surgical robot system according to Example 1, wherein the controller is further configured to detect an over-torque condition based on a measured torque of any of the plurality of motors exceeding a torque threshold.

[0066] Example 10. A surgical robot system comprising: a plurality of motors, each of the plurality of motors including a torque sensor for measuring the torque of a corresponding motor among the plurality of motors and a position sensor for measuring the position of a corresponding motor among the plurality of motors; an instrument comprising: a shearing end effector having a first blade and a second blade; a first cable coupled to the first blade and actuable by a first motor among the plurality of motors; and a second cable coupled to the second blade and actuable by at least a second motor among the plurality of motors, wherein the first cable and the second cable respectively move the first blade and the second blade from an open position to a closed position; and a controller configured to: receive an input including an overtravel command instructing the plurality of motors to apply force to the first blade and the second blade; calculate a desired angle between the first blade and the second blade based on the measured position of each of the plurality of motors; compare the desired angle between the first blade and the second blade with the first threshold; and adjust the overtravel command if the desired angle between the first blade and the second blade is less than the first threshold.

[0067] Example 11. The surgical robot system according to Example 10, wherein the controller is further configured to calculate the derivative of the desired angle between the first blade and the second blade.

[0068] Example 12. The surgical robot system according to Example 11, wherein the controller is further configured to calculate the absolute value of the derivative of the desired angle between the first blade and the second blade.

[0069] Example 13. The surgical robot system according to Example 12, wherein the controller is further configured to compare the absolute value of the derivative of the desired angle between the first blade and the second blade with a second threshold.

[0070] Example 14. The surgical robot system according to Example 13, wherein the controller is further configured to determine whether to adjust the overtravel command if the desired angle between the first blade and the second blade is lower than the first threshold and the absolute value of the derivative of the desired angle between the first blade and the second blade is lower than the second threshold.

[0071] Example 15. The surgical robot system according to Example 10, wherein the controller is further configured to calculate the force for the overtravel command based on the desired angle between the first blade and the second blade.

[0072] Example 16. The surgical robot system according to Example 15, wherein the controller is further configured to adjust the force for the overtravel command using a scaling factor selected based on the desired angle between the first blade and the second blade.

[0073] Example 17. The surgical robot system according to Example 10, wherein the controller is further configured to detect an over-torque condition based on the measured torque of any of the plurality of motors exceeding a torque threshold.

[0074] Example 18. A method for controlling a surgical robotic instrument, the method comprising: moving a first gripper and a second gripper from an open position to a closed position, wherein the first gripper is coupled to a first cable actuated by a first motor, and the second gripper is coupled to a second cable actuated by a second motor; measuring angular positions of the first motor and the second motor; receiving input including an overtravel command instructing the first motor and the second motor to apply forces to the first gripper and the second gripper; calculating a desired angle between the first gripper and the second gripper based at least on the measured angular positions of the first motor and the second motor; comparing the desired angle between the first gripper and the second gripper with the first threshold; and adjusting the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold.

[0075] Example 19. The method according to Example 18 further includes: calculating the derivative of the desired angle between the first gripper and the second gripper; and calculating the absolute value of the derivative of the desired angle between the first gripper and the second gripper.

[0076] Example 20. The method according to Example 19 further includes: comparing the absolute value of the derivative of the desired angle between the first gripper and the second gripper with a second threshold; and if the desired angle between the first gripper and the second gripper is lower than the first threshold and the absolute value of the derivative of the desired angle between the first gripper and the second gripper is lower than the second threshold, then determining whether to adjust the overtravel command.

Claims

1. A surgical robot system (10), comprising: Instrument driving unit (52), the instrument driving unit includes: A plurality of motors (152a-d), each of the plurality of motors including a torque sensor (155) for measuring the torque of a corresponding motor among the plurality of motors and a position sensor (157) for measuring the position of a corresponding motor among the plurality of motors. Instrument (50), the instrument being connected to the instrument drive unit, the instrument comprising: An end effector (200) having a first gripper (120, 120') and a second gripper (122, 122'). A first cable (201a, 201d), the first cable being connected to the first gripper and capable of being actuated by at least one of the plurality of motors; and A second cable (201b, 201c), the second cable being connected to the second gripper and actuated by at least the second of the plurality of motors, wherein the first cable and the second cable respectively move the first gripper and the second gripper between an open position and a closed position; and Controllers (21a, 41d), the controllers being configured to: Receive input, the input including an overtravel command, the overtravel command instructing the plurality of motors to apply force to the first gripper and the second gripper; The desired angle between the first gripper and the second gripper is calculated based on the measured position of each of the plurality of motors; Compare the desired angle between the first gripper and the second gripper with a first threshold; and If the desired angle between the first gripper and the second gripper is lower than the first threshold, then the overtravel command is adjusted.

2. The surgical robot system according to claim 1, wherein, The controller is further configured to calculate the derivative of the desired angle between the first gripper and the second gripper.

3. The surgical robot system according to claim 2, wherein, The controller is further configured to calculate the absolute value of the derivative of the desired angle between the first gripper and the second gripper.

4. The surgical robot system according to claim 3, wherein, The controller is further configured to compare the absolute value of the derivative of the desired angle between the first gripper and the second gripper with a second threshold.

5. The surgical robot system according to claim 4, wherein, The controller is further configured to determine whether to adjust the overtravel command if the desired angle between the first gripper and the second gripper is lower than the first threshold and the absolute value of the derivative of the desired angle between the first gripper and the second gripper is lower than the second threshold.

6. The surgical robot system according to any of the preceding claims, wherein, The end effector is a shear (200'), and each of the first and second grippers includes a blade.

7. The surgical robot system according to any of the preceding claims, wherein, The controller is further configured to calculate the force for the overtravel command based on the desired angle between the first gripper and the second gripper.

8. The surgical robot system according to claim 7, wherein, The controller is further configured to adjust the force for the overtravel command using a scaling factor selected based on the desired angle between the first gripper and the second gripper.

9. The surgical robot system according to any of the preceding claims, wherein, The controller is further configured to detect over-torque conditions based on the measured torque of any of the plurality of motors exceeding a torque threshold.

10. A method for controlling a surgical robotic instrument (50), the method comprising: The first gripper (120) and the second gripper (122) are moved from the open position to the closed position, wherein the first gripper is connected to a first cable (201a, 201d) that can be actuated by a first motor (152a), and the second gripper is connected to a second cable (201b, 201c) that can be actuated by a second motor (152b). Measure the angular position of the first motor and the angular position of the second motor; Receive input, the input including an overtravel command, the overtravel command instructing the first motor and the second motor to apply force to the first gripper and the second gripper; The desired angle between the first gripper and the second gripper is calculated based at least on the measured angular positions of the first motor and the second motor. Compare the desired angle between the first gripper and the second gripper with a first threshold; and If the desired angle between the first gripper and the second gripper is lower than the first threshold, then the overtravel command is adjusted.

11. The method of claim 10, further comprising: Calculate the derivative of the desired angle between the first gripper and the second gripper; as well as Calculate the absolute value of the derivative of the desired angle between the first gripper and the second gripper.

12. The method of claim 11, further comprising: The absolute value of the derivative of the desired angle between the first gripper and the second gripper is compared with the second threshold. as well as If the desired angle between the first gripper and the second gripper is lower than the first threshold and the absolute value of the derivative of the desired angle between the first gripper and the second gripper is lower than the second threshold, then it is determined whether to adjust the overtravel command.

Images