Robotic surgical system and calibration method

Abstract

To provide a robot surgery system capable of suppressing a decrease in grip force of jaw members in a configuration for controlling drive of the jaw members of a surgical instrument at a motor rotation angle.SOLUTION: A robot surgery system 100 includes: a surgical instrument 40 including a pair of jaw members 43a, 43b opened / closed by cables A1, A2; a robot arm 21a including a motor 212a driving the cables A1, A2 and fitted by the surgical instrument 40; a storage part 45 storing value θ1 corresponding to a rotation angle of the motor 212a when prescribed current value I1 occurs; and a controller 24 which performs calibration that acquires value θ2 corresponding to a rotation angle of the motor 212a when the prescribed value current value I1 occurs and changes a command angle of a closing operation of the jaw members 43a, 43b on the basis of value θ2 and the value θ1.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] This invention relates to robotic surgical systems and calibration Regarding the method, in particular, a robotic surgical system that controls the drive of a pair of jaw members by the rotation angle of a motor and calibration Regarding the method. [Background technology]

[0002] Conventionally, robotic surgical systems are known that include surgical instruments comprising a pair of jaw members that are opened and closed by a cable (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a robotic surgical system comprising a surgical instrument including a pair of jaw members that are opened and closed by a cable. In this robotic surgical system, the cable driving the pair of jaw members stretches during use of the surgical instrument, preventing the pair of jaw members from exerting the desired gripping force. Therefore, the system compensates for the stretching of the cable. Specifically, in this robotic surgical system, the motor is controlled by torque to drive the jaw members within a predetermined torque range between an upper torque limit and a lower torque limit. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] U.S. Patent No. 9014856 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In the robotic surgery system described in the above Patent Document 1, the motor that drives the jaw member is controlled by torque. However, there are cases where it is effective to control the motor that drives the jaw member by the rotation angle. For example, when the motor is controlled by torque, if a speed reducer with a high reduction ratio is used, the behavior of the tip side of the surgical instrument is less likely to be reflected as a change in the torque of the motor. In this case, it becomes difficult to detect the behavior of the tip side of the surgical instrument by detecting a change in the torque of the motor. To solve this problem, it is effective to control the motor that drives the jaw member by the rotation angle. However, when the motor that drives the jaw member is controlled by the rotation angle, the method described in the above Patent Document 1 cannot be used. Therefore, in a configuration in which the driving of the jaw member is controlled by the rotation angle of the motor, it is desired to suppress a decrease in the gripping force of the jaw member.

[0006] This invention provides a robotic surgery system and a calibration method capable of suppressing a decrease in the gripping force of a jaw member in a configuration in which the driving of the jaw member of a surgical instrument is controlled by the rotation angle of a motor.

Means for Solving the Problems

[0007] The robotic surgery system according to the first aspect of this invention includes a surgical instrument including a pair of jaw members opened and closed by an elongated element, a robotic arm including a motor that drives the elongated element, and the surgical instrument is attached thereto, and the rotation angle of the motor when it reaches a predetermined current value proportional to a predetermined ratio A first storage unit that stores in advance a first value to be proportional to a predetermined ratio A second value to be obtained for the rotation angle of the motor when it reaches a predetermined current value is obtained, and the obtained second value and When it differs from the first value, Based on the first value and The second value and A control unit that performs calibration to change the command angle of the closing operation of the jaw member is provided The command angle for the closing operation of the pair of jaw members is an angle proportional to a predetermined ratio to the rotation angle commanded to the motor when the control unit causes the motor to rotate in the closing direction to generate a closing force on the pair of jaw members from a state where the opening angle of the pair of jaw members is zero. .

[0008] In the robotic surgery system according to the first aspect of the present invention, as described above, a control unit for performing calibration is provided, which acquires a second value corresponding to the rotation angle of the motor when a predetermined current value is reached, and changes the command angle of the closing operation of the jaw member based on the acquired second value and the first value stored in the first storage unit. Thereby, in a configuration in which the driving of the jaw member of the surgical instrument is controlled by the rotation angle of the motor, calibration for compensating for the elongation of the slender element can be performed, so that in a configuration in which the driving of the jaw member of the surgical instrument is controlled by the rotation angle of the motor, a decrease in the gripping force of the jaw member can be suppressed.

[0009] According to the second aspect of the present invention calibration The method includes a surgical instrument including a pair of jaw members opened and closed by a slender element, a motor for driving the slender element, and a robotic arm to which the surgical instrument is attached, A storage unit that stores in advance a first value that is proportional to a predetermined ratio to the rotation angle of the motor when a predetermined current value is obtained, and a control unit, and is for controlling a robotic surgery system Calibration performed by the department The method includes a step of acquiring a second value corresponding to the rotation angle of the motor when a predetermined current value is reached, and proportional to a predetermined ratio a step of performing calibration to change the command angle of the closing operation of the jaw member based on the acquired second value and When the first value is different, a first value The second value and thereby including. The command angle for the closing operation of the pair of jaw members is an angle proportional to a predetermined ratio to the rotation angle commanded to the motor when the control unit causes the motor to rotate in the closing direction to generate a closing force on the pair of jaw members from a state where the opening angle of the pair of jaw members is zero. .

[0010] According to the second aspect of the present invention calibration The method includes a step of acquiring a second value corresponding to the rotation angle of the motor when a predetermined current value is reached, corresponding to the first value, and a step of performing calibration to change the command angle of the closing operation of the jaw member based on the acquired second value and the first value stored in advance. Thereby, in a configuration in which the driving of the jaw member of the surgical instrument is controlled by the rotation angle of the motor, calibration for compensating for the elongation of the slender element can be performed, so that in a configuration in which the driving of the jaw member of the surgical instrument is controlled by the rotation angle of the motor, it is possible to suppress a decrease in the gripping force of the jaw member calibrationWe can provide a method. [Effects of the Invention]

[0011] According to the present invention, in a configuration in which the drive of the jaw member of a surgical instrument is controlled by the rotation angle of a motor, a robotic surgical system is possible in which a decrease in the gripping force of the jaw member can be suppressed. calibration We can provide a method. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows the configuration of a robotic surgical system according to one embodiment. [Figure 2] This is a block diagram showing the control configuration of a robotic surgical system according to one embodiment. [Figure 3] This figure shows the configuration of an operating handle according to one embodiment. [Figure 4] This is a perspective view showing a robotic arm according to one embodiment, with surgical instruments attached via an adapter. [Figure 5] This is an exploded perspective view showing a robotic arm in which surgical instruments are attached via an adapter, according to one embodiment. [Figure 6] This is a perspective view of a surgical instrument according to one embodiment, seen from below. [Figure 7] This is a perspective view showing a surgical instrument in which the cover portion has been removed from the base of one embodiment. [Figure 8] This is a plan view showing a surgical instrument in which the cover portion has been removed from the base according to one embodiment. [Figure 9] This is a perspective view showing the end effector of a surgical instrument according to one embodiment. [Figure 10] This figure shows a pair of jaw members, a motor, a speed reducer, a current detection unit, a position detection unit, and a controller according to one embodiment. [Figure 11] This graph illustrates calibration according to one embodiment. [Figure 12]This is a flowchart illustrating the control process when attaching a surgical instrument to a robotic arm according to one embodiment. [Figure 13] This is a flowchart illustrating the control process of the calibration mode according to one embodiment. [Figure 14] This graph illustrates calibration through modification. [Figure 15] This graph illustrates the calibration process using a modified example shown in Figure 14. [Modes for carrying out the invention]

[0013] The embodiments will be described below with reference to the drawings.

[0014] Hereinafter, an embodiment of the present invention will be described based on the drawings.

[0015] (Configuration of the robotic surgical system) Referring to Figures 1 and 2, the configuration of a robotic surgical system 100 according to one embodiment will be described.

[0016] As shown in Figure 1, the robotic surgical system 100 comprises a remote control device 10, which is the operator's device, and a patient-side device 20, which is a surgical assistance robot. The remote control device 10 is provided for remotely controlling medical equipment installed on the patient-side device 20. When the operator, who is the surgeon, inputs an operation command to be performed by the patient-side device 20 to the remote control device 10, the remote control device 10 transmits the operation command to the patient-side device 20 via the controller 24. The patient-side device 20 then operates medical equipment such as surgical instruments 40 attached to the robot arm 21a and an endoscope 50 attached to the robot arm 21b in response to the operation command transmitted from the remote control device 10. This enables minimally invasive surgery. Note that the controller 24 is an example of a control unit.

[0017] The patient-side device 20 constitutes an interface for performing surgery on patient P. The patient-side device 20 is positioned beside the operating table 30 on which patient P lies. The patient-side device 20 comprises a plurality of robotic arms 21a, 21b, an arm base 22, a positioner 23, a controller 24, a memory unit 25, and a temporary memory unit 26. An endoscope 50 is attached to one of the robotic arms 21b, and surgical instruments 40 are attached to the other robotic arms 21a. Each robotic arm 21a, 21b is commonly supported by the arm base 22. The plurality of robotic arms 21a, 21b have multiple joints, and each joint is provided with a drive unit including a servo motor and a position detector such as an encoder. The robotic arms 21a, 21b are configured to be controlled by drive signals given via the controller 24 so that the medical instruments attached to the robotic arms 21a, 21b perform desired movements.

[0018] The arm base 22 is supported by a positioner 23 placed on the floor of the operating room. The positioner 23 includes a vertical articulated robot. The positioner 23 is configured to move the position of the arm base 22 in three dimensions. The controller 24 is a control circuit having an arithmetic unit such as a CPU and memory such as ROM and RAM. The storage unit 25 is data storage, and the threshold θ described later S1 And the threshold θ, which will be discussed later. S2 The following is stored. The temporary storage unit 26 stores the difference Δθ, which will be described later. The storage unit 25 and the temporary storage unit 26 are provided in the robot body 27 on which the robot arms 21a and 21b are provided. Note that the temporary storage unit 26 is an example of a second storage unit. Threshold θ S1 This is an example of a second threshold. Threshold θ S2 This is an example of the first threshold.

[0019] A surgical instrument 40, which serves as a medical device, is detachably attached to the tip of the robotic arm 21a. The surgical instrument 40 comprises a housing 41 (see Figure 4) attached to the robotic arm 21a, an elongated shaft 42 (see Figure 4), and an end effector 43 (see Figure 4) provided at the tip (distal end) of the shaft 42. Examples of end effectors 43 include, but are not limited to, grasping forceps, scissors, hooks, high-frequency knives, snare wires, clamps, staplers, clip applicators, electrosurgical units, and needles; various treatment instruments can be applied. In surgery using the patient-side device 20, the robotic arm 21a introduces the surgical instrument 40 into the patient P's body via a cannula (trocker) placed on the patient P's body surface. The end effector 43 of the surgical instrument 40 is then positioned near the surgical site.

[0020] An endoscope 50, used as a medical instrument, is detachably attached to the tip of the robotic arm 21b. The endoscope 50 is used to photograph the inside of the patient P's body cavity, and the captured images are output to the remote control device 10. A 3D endoscope or a 2D endoscope capable of capturing three-dimensional images is used as the endoscope 50. In surgery using the patient-side device 20, the robotic arm 21b introduces the endoscope 50 into the patient P's body via a trocker placed on the patient P's body surface. The endoscope 50 is then positioned near the surgical site.

[0021] The remote control device 10 constitutes an interface with the operator. The remote control device 10 is a device for the operator to operate medical instruments attached to the robot arms 21a and 21b. Specifically, the remote control device 10 is configured to transmit operation commands to be performed by the surgical instruments 40 and endoscope 50, which are input by the operator, to the patient-side device 20 via the controller 24. The remote control device 10 is installed, for example, next to the operating table 30 so that the operator can clearly see the patient P while operating the master. It is also possible to install the remote control device 10 in a room separate from the operating room where the operating table 30 is installed, for example, by transmitting operation commands wirelessly.

[0022] The actions to be performed by the surgical instrument 40 are the actions (a series of positions and postures) of the surgical instrument 40 and the actions realized by the individual functions of the surgical instrument 40. For example, if the surgical instrument 40 is a grasping forceps, the actions to be performed by the surgical instrument 40 are the roll rotation position and pitch rotation position of the wrist of the end effector 43 and the opening and closing of the jaws. If the surgical instrument 40 is a high-frequency knife, the actions to be performed by the surgical instrument 40 may be the vibration action of the high-frequency knife, specifically the supply of current to the high-frequency knife. If the surgical instrument 40 is a snare wire, the actions to be performed by the surgical instrument 40 may be the binding action and the release action of the binding state. It may also be the action of burning the surgical site by supplying current to the bipolar or monopolar.

[0023] The actions to be performed by the endoscope 50 include, for example, setting the position and orientation of the tip of the endoscope 50, or the zoom magnification.

[0024] As shown in Figures 1 and 2, the remote control device 10 includes an operating handle 11, an operating pedal section 12, a display section 13, a touch panel 14, and a control device 15.

[0025] The operating handles 11 are provided for remotely operating medical instruments attached to the robot arms 21a and 21b. Specifically, the operating handles 11 receive input from an operator for controlling medical instruments (surgical instruments 40, endoscope 50). There are two operating handles 11, arranged horizontally. That is, one of the two operating handles 11 is operated by the operator's right hand, and the other operating handle 11 is operated by the operator's left hand.

[0026] Furthermore, the operating handle 11 is positioned to extend from the rear side of the remote control device 10 toward the front side. The operating handle 11 is configured to be movable within a predetermined three-dimensional operating area. That is, the operating handle 11 is configured to be movable in the vertical, horizontal, forward, backward, and rotational directions.

[0027] As shown in Figure 3, the operating handle 11 is a hand controller operated by the operator. The operating handle 11 has a support member 11a, a pair of grip members 11b provided on both sides of the support member 11a, and finger insertion parts 11c provided on each of the pair of grip members 11b. The operator operates the operating handle 11 by inserting their fingers (such as the thumb and middle finger) into the pair of finger insertion parts 11c. That is, the base ends of the pair of grip members 11b are rotatably connected to the support member 11a, and by increasing or decreasing the opening angle of the pair of grip members 11b, the opening angle of the pair of jaw members 43a, 43b, which will be described later, is changed. Commands to open and close the pair of jaw members 43a, 43b are input to the operating handle 11. The opening angle of the pair of grip members 11b is detected, for example, by a sensor. For example, the operating handle 11 has a Hall sensor on the support member 11a and magnets on one or both of the pair of grip members 11b, thereby detecting the opening angle of the pair of grip members 11b. Alternatively, the operating handle 11 has a Hall sensor on one of the pair of grip members 11b and a magnet on the other of the pair of grip members 11b, thereby detecting the opening angle of the pair of grip members 11b. Based on the detected signal regarding the opening angle of the pair of grip members 11b, the pair of jaw members 43a, 43b are opened and closed.

[0028] As shown in Figure 1, the remote control device 10 and the patient-side device 20 constitute a master-slave system for controlling the movements of robot arms 21a and 21b. That is, the operating handle 11 constitutes the master-side operating unit in the master-slave system, and robot arms 21a and 21b, to which medical instruments are attached, constitute the slave-side operating unit. When the operator operates the operating handle 11, the movement of robot arm 21a or robot arm 21b is controlled so that the tip of robot arm 21a (end effector 43 of surgical instrument 40) or the tip of robot arm 21b (endoscope 50) traces the movement of the operating handle 11.

[0029] Furthermore, the patient-side device 20 is configured to control the movement of the robot arm 21a according to the set motion magnification. For example, when the motion magnification is set to 1 / 2x, the end effector 43 of the surgical instrument 40 is controlled to move a distance equal to half the movement distance of the operating handle 11. This allows for precise and detailed surgical procedures to be performed.

[0030] The operating pedal section 12 includes multiple pedals for performing functions related to the medical device. These multiple pedals include a coagulation pedal, a cutting pedal, a camera pedal, and a clutch pedal. The multiple pedals are operated by the operator's feet.

[0031] The coagulation pedal allows the surgical instrument 40 to coagulate the surgical site. Specifically, when the coagulation pedal is operated, a coagulation voltage is applied to the surgical instrument 40, causing the surgical site to coagulate. The cutting pedal allows the surgical instrument 40 to cut the surgical site. Specifically, when the cutting pedal is operated, a cutting voltage is applied to the surgical instrument 40, causing the surgical site to cut.

[0032] The camera pedal is used to control the position and orientation of the endoscope 50, which images the inside of the body cavity. Specifically, the camera pedal enables the operation of the endoscope 50 by the operating handle 11. In other words, while the camera pedal is pressed, the position and orientation of the endoscope 50 can be controlled by the operating handle 11. For example, the endoscope 50 is operated using both the left and right operating handles 11. Specifically, the endoscope 50 is rotated by rotating the left and right operating handles 11 around their midpoint. Also, by pushing both the left and right operating handles 11 inward, the endoscope 50 moves inward. Also, by pulling both the left and right operating handles 11 outward, the endoscope 50 moves forward. Also, by moving both the left and right operating handles 11 up, down, left, and right, the endoscope 50 moves up, down, left, and right.

[0033] The clutch pedal is used to temporarily disconnect the operating connection between the robot arm 21a and the operating handle 11, thereby stopping the operation of the surgical instrument 40. Specifically, while the clutch pedal is being operated, the robot arm 21a of the patient-side device 20 will not move even if the operating handle 11 is operated. For example, when the operating handle 11 moves to near the end of its movable range, operating the clutch pedal temporarily disconnects the operating connection and returns the operating handle 11 to near the center position. When the operation of the clutch pedal is stopped, the robot arm 21a and the operating handle 11 are reconnected, and operation of the operating handle 11 can be resumed near the center.

[0034] The display unit 13 is capable of displaying images captured by the endoscope 50. The display unit 13 consists of a scope-type display unit or a non-scope-type display unit (Figure 1 shows a scope-type display unit). A scope-type display unit is, for example, a display unit that you look into. A non-scope-type display unit is a concept that includes an open-type display unit with a flat screen that is not the type you look into, such as the display of a normal personal computer.

[0035] When a scope-type display unit is installed, a 3D image captured by the endoscope 50 attached to the robot arm 21b of the patient-side device 20 is displayed. Even when a non-scope-type display unit is installed, a 3D image captured by the endoscope 50 provided on the patient-side device 20 is displayed. In addition, when a non-scope-type display unit is installed, a 2D image captured by the endoscope 50 provided on the patient-side device 20 may be displayed.

[0036] The touch panel 14 serves as both an operation unit and a display unit. The touch panel 14 displays a screen for operating the settings of the remote control device 10 and accepts operation requests for the settings of the remote control device 10.

[0037] As shown in Figure 2, the control device 15 includes, for example, a control unit 151 having an arithmetic unit such as a CPU, a storage unit 152 having memory such as ROM and RAM, and an image control unit 153. The control device 15 may be composed of a single control device that provides centralized control, or it may be composed of multiple control devices that cooperate with each other to provide distributed control. The control unit 151 determines, according to the switching state of the operating pedal unit 12, whether the operation mode command input by the operating handle 11 is an operation mode command that should be executed by the robot arm 21a or an operation mode command that should be executed by the endoscope 50. When the control unit 151 determines that the operation mode command input to the operating handle 11 is an operation mode command that should be executed by the surgical instrument 40, it transmits the operation mode command to the robot arm 21a via the controller 24. As a result, the controller 24 drives the robot arm 21a, and this drive controls the operation of the surgical instrument 40 attached to the robot arm 21a.

[0038] Furthermore, when the control unit 151 determines that the operation command input to the operating handle 11 is an operation command that should be executed by the endoscope 50, it transmits the operation command to the robot arm 21b via the controller 24. This drives the robot arm 21b, and this drive controls the operation of the endoscope 50 attached to the robot arm 21b.

[0039] For example, the memory unit 152 stores control programs corresponding to the type of surgical instrument 40, and the control unit 151 reads these control programs according to the type of surgical instrument 40 that is attached, thereby enabling the operation commands of the operating handle 11 and / or operating pedal unit 12 of the remote control device 10 to operate in a manner that is appropriate for the individual surgical instrument 40.

[0040] The image control unit 153 transmits the image acquired by the endoscope 50 to the display unit 13. The image control unit 153 performs image processing and modification as needed.

[0041] (Configuration of surgical instruments, adapters, drapes, and robotic arms) Next, the configuration of the surgical instrument 40, adapter 60, drape 70, and robot arm 21a will be described with reference to Figures 4 to 6.

[0042] Here, the direction in which the surgical instrument 40 extends (the direction in which the shaft 42 extends) is defined as the Y direction, the direction toward the tip of the surgical instrument 40 (the direction toward the end effector 43) within the Y direction is defined as the Y1 direction, and the direction opposite to the Y1 direction is defined as the Y2 direction. The direction in which the surgical instrument 40 and the adapter 60 are adjacent is defined as the Z direction, the direction toward the surgical instrument 40 within the Z direction is defined as the Z1 direction, and the direction opposite to the Z1 direction is defined as the Z2 direction. Furthermore, the direction perpendicular to the Y and Z directions is defined as the X direction, one side of the X direction is defined as the X1 direction, and the other side of the X direction is defined as the X2 direction.

[0043] As shown in Figures 4 and 5, the surgical instrument 40 is detachably attached to the robot arm 21a. Specifically, the surgical instrument 40 is detachably attached to the robot arm 21a via an adapter 60. The adapter 60 is a drape adapter for sandwiching a sterile drape 70, which covers the robot arm 21a, between the robot arm 21a and the adapter 60.

[0044] The surgical instrument 40 is attached to the Z1 side of the adapter 60. The adapter 60 is attached to the Z1 side of the robot arm 21a.

[0045] The robotic arm 21a is covered with a drape 70 because it is used in a sterile area. In the operating room, sterile procedures are performed to prevent contamination of the surgically incised area and medical instruments by pathogens or foreign objects. In these sterile procedures, a sterile area and a contaminated area (areas outside the sterile area) are established. The surgical site is located in the sterile area. During surgery, members of the surgical team, including the operator, ensure that only sterilized objects are located in the sterile area, and when moving objects located in the contaminated area to the sterile area, these objects are sterilized. Similarly, when an assistant of the surgical team, including the operator, places their hands in the contaminated area, they sterilize their hands before directly touching objects located in the sterile area. Instruments used in the sterile area are sterilized or covered with a sterilized drape 70.

[0046] As shown in Figure 5, the drape 70 comprises a main body portion 71 that covers the robot arm 21a and a mounting portion 72 that is sandwiched between the robot arm 21a and the adapter 60. The main body portion 71 is made of a flexible film member formed in a film shape. The flexible film member is made of a resin material such as thermoplastic polyurethane or polyethylene. The main body portion 71 is provided with an opening so that the robot arm 21a and the adapter 60 can engage with each other. The mounting portion 72 is provided in the opening of the main body portion 71. The mounting portion 72 is made of a resin molded member. The resin molded member is made of a resin material such as polyethylene terephthalate. The mounting portion 72 is formed to be harder (less flexible) than the main body portion 71. The mounting portion 72 is provided with an opening so that the robot arm 21a and the adapter 60 can engage with each other. The opening of the mounting portion 72 may be provided so as to correspond to the engagement portion between the robot arm 21a and the adapter 60. Furthermore, the openings in the mounting portion 72 may be provided in multiple locations to correspond to multiple engagement points between the robot arm 21a and the adapter 60.

[0047] As shown in Figures 5 and 6, the surgical instrument 40 has a plurality (4) of driven members 44a, 44b, 44c, and 44d, and a storage unit 45. The storage unit 45 is provided inside the housing 41. The storage unit 45 stores the serial number representing the surgical instrument 40, the number of times the surgical instrument 40 has been used, a value θ1 (described later), and a value θ0. In this embodiment, the value θ1 is set to approximately half of the value θ0. When the surgical instrument 40 is attached to the robot arm 21a, the storage unit 45 is connected to the controller 24 for communication. The storage unit 45 is an example of a first storage unit. The value θ1 is an example of a first value. The value θ0 is an example of a third value.

[0048] The driven members 44a to 44d are provided within the housing 41 and are rotatable about a rotation axis extending in the Z direction. The multiple driven members 44a to 44d are provided to operate (drive) the end effector 43. The driven members 44b to 44d are connected to the end effector 43 by a cable A, which is an elongated element inserted into the shaft 42. As a result, the cable A is driven in accordance with the rotation of the driven members 44b to 44d, and the end effector 43 is operated (driven) in accordance with the drive of the cable A. In addition, the driven member 44a is connected to the shaft 42 via a gear 42a (see Figure 7). As a result, the shaft 42 is rotated in accordance with the rotation of the driven member 44a, and the end effector 43 also rotates in accordance with the rotation of the shaft 42.

[0049] Each of the multiple driven members 44a to 44d includes projections 441 and 442 that engage with the drive transmission member 61 of the adapter 60 in order to transmit the driving force from the robot arm 21a to the end effector 43. The projections 441 and 442 protrude from the Z2-direction side surface of the driven members 44a to 44d toward the adapter 60 side (Z2 direction side). In addition, the projections 441 and 442 are arranged in a straight line. Furthermore, the projections 441 provided on the driven members 44a and 44b and the projections 442 provided on the driven members 44c and 44d have different shapes from each other.

[0050] As shown in Figure 5, the adapter 60 has a plurality (four) of drive transmission members 61. The drive transmission members 61 are configured to transmit the driving force from the robot arm 21a to the driven members 44a to 44d of the surgical instrument 40. In other words, the drive transmission members 61 are provided to correspond to the driven members 44a to 44d of the surgical instrument 40. The drive transmission members 61 are provided to be rotatable about a rotation axis extending in the Z direction.

[0051] Each of the multiple drive transmission members 61 includes an engagement recess 611 that engages with the projections 441 and 442 of the driven members 44a to 44d of the surgical instrument 40. The engagement recess 611 is provided on the surgical instrument 40 side (Z1 direction side) of the drive transmission member 61 and is recessed from the Z1 direction side surface of the drive transmission member 61 toward the opposite side from the surgical instrument 40 (Z2 direction side). Each of the multiple drive transmission members 61 includes an engagement recess on the Z2 direction side surface that engages with the engagement projection 213 of the robot arm 21a.

[0052] The robot arm 21a has a frame 211, a plurality (4) of drive units 212, and a plurality of engaging protrusions 213. The plurality of drive units 212 are provided to correspond to the plurality (4) of driven members 44a to 44d of the surgical instrument 40 and the plurality (4) of drive transmission members 61 of the adapter 60, respectively. The drive units 212 are configured to rotationally drive the engaging protrusions 213 around a rotation axis extending in the Z direction. The engaging protrusions 213 engage with the engaging recesses on the Z2 direction side surface of the drive transmission member 61. The engaging protrusions 213 project from the Z1 direction side surface of the robot arm 21a toward the Z1 direction side (adapter 60 side). The drive unit 212 is configured to rotate the drive transmission member 61 of the adapter 60, which is engaged with the engaging projection 213, around a rotation axis extending in the Z direction, and also to rotate the driven members 44a to 44d of the surgical instrument 40, which are engaged with the drive transmission member 61, around a rotation axis extending in the Z direction.

[0053] (Detailed configuration of surgical instruments) Next, the detailed configuration of the surgical instrument 40 will be described with reference to Figures 7 to 9. Here, an example will be described in which the end effector 43 of the surgical instrument 40 is a gripping forceps having a pair of jaw members 43a and 43b. Note that the surgical instrument of the present invention only needs to have a pair of jaw members, and the pair of jaw members may be, for example, scissors.

[0054] As shown in Figures 7 and 8, the cable A is wound around the driven members 44b to 44d of the surgical instrument 40. In other words, the cable A is connected to the driven members 44b to 44d.

[0055] The cable A3 is wound around the driven member 44b. Specifically, the first portion A3a of the cable A3 is wound around the upper part of the driven member 44b in a clockwise direction, and the second portion A3b of the cable A3 is wound around the lower part of the driven member 44b in a counterclockwise direction.

[0056] Furthermore, the cable A1 is wound around the driven member 44c. Specifically, the first portion A1a of the cable A1 is wound around the upper part of the driven member 44c in a clockwise direction, and the second portion A1b of the cable A1 is wound around the lower part of the driven member 44c in a counterclockwise direction.

[0057] Furthermore, the cable A2 is wound around the driven member 44d. Specifically, the first portion A2a of the cable A2 is wound around the upper part of the driven member 44d in a clockwise direction, and the second portion A2b of the cable A2 is wound around the lower part of the driven member 44d in a counterclockwise direction.

[0058] Cable A is routed from each of the driven members 44b to 44d, through shaft 42, onto end effector 43, and then back through shaft 42 to reach the driven members 44b to 44d. Cable A is also routed onto pulley 46. Pulley 46 is held in place by pulley holder 461.

[0059] As shown in Figures 8 and 9, the driven member 44c rotates around its axis of rotation, thereby operating the jaw member 43a of the jaw members 43a and 43b of the end effector 43. Specifically, the driven member 44c is rotated by the drive unit 212, which drives the cable A1. The cable A1 connects the jaw member 43a and the driven member 44c via the inside of the shaft 42. Specifically, the cable A1 is wound around a pulley 43d provided at the base of the jaw member 43a. By rotating in the C1 direction (see Figure 8), the driven member 44c pulls the first portion A1a of the cable A1 and feeds out the second portion A1b, driving the jaw member 43a in the C1a direction (see Figure 9), which is the direction in which the jaw member 43a opens. Furthermore, the driven member 44c rotates in the C2 direction (see Figure 8), which is opposite to the C1 direction, pulling the second portion A1b of the cable A1 and extending the first portion A1a, thereby driving the jaw member 43a in the C2a direction (see Figure 9), which is the direction in which the jaw member 43a closes.

[0060] The driven member 44d rotates around the axis of rotation, thereby operating the jaw member 43b of the jaw members 43a and 43b of the end effector 43. Specifically, the driven member 44d is rotated by the drive unit 212, which drives the cable A2. The cable A2 connects the jaw member 43b and the driven member 44d via the inside of the shaft 42. Specifically, the cable A2 is wrapped around a pulley 43e provided at the base of the jaw member 43b. By rotating in the C3 direction (see Figure 8), the driven member 44d pulls the first portion A2a of the cable A2 and feeds out the second portion A2b, driving the jaw member 43b in the C3a direction (see Figure 9), which is the direction in which the jaw member 43b opens. Furthermore, the driven member 44d rotates in the C4 direction (see Figure 8), which is opposite to the C3 direction, pulling the second portion A2b of cable A2 and extending the first portion A2a, thereby driving the jaw member 43b in the C4a direction (see Figure 9), which is the direction in which the jaw member 43b closes. The jaw members 43a and 43b are opened and closed by the driving of cable A by the driven members 44b and 44c. Note that cables A1 and A2 are examples of elongated elements.

[0061] The driven member 44b operates the wrist portion 43c of the end effector 43 by rotating around its axis of rotation. Specifically, the driven member 44b is rotated by the drive unit 212, thereby driving the cable A3. The cable A3 connects the wrist portion 43c and the driven member 44b via the inside of the shaft 42. By rotating in the C5 direction (see Figure 8), the driven member 44b pulls the first portion A3a of the cable A3 and feeds out the second portion A3b, driving the wrist portion 43c in the C5a direction (see Figure 9). Also, by rotating in the C6 direction (see Figure 8), which is opposite to the C5 direction, the driven member 44b pulls the second portion A3b of the cable A3 and feeds out the first portion A3a, driving the wrist portion 43c in the C6a direction (see Figure 9), which is opposite to the C5a direction.

[0062] The driven member 44a, which has a gear 443, is rotated by the drive unit 212 around its axis of rotation while the gear 42a connected to the proximal end of the shaft 42 is engaged with the gear 443, thereby operating the shaft 42 and the end effector 43. Specifically, the driven member 44a rotates in the C7 direction (see Figure 8), driving the shaft 42 to rotate in the C7a direction (see Figure 9), and thus driving the end effector 43 to rotate in the C7a direction. Also, the driven member 44a rotates in the C8 direction (see Figure 8), driving the shaft 42 to rotate in the C8a direction (see Figure 9), which is the opposite direction to the C7a direction, and thus driving the end effector 43 to rotate in the C8a direction.

[0063] (Configuration related to the opening and closing of the jaw member) Next, the configuration of the opening and closing of the jaw members 43a and 43b will be described with reference to Figures 10 and 11.

[0064] As shown in Figure 10, the drive unit 212 includes a motor 212a, a reduction gear 212b, and a position detection unit 212c. The motor 212a is a servo motor and is a drive source that drives the cable A1 (A2) and the jaw member 43a (43b). The reduction gear 212b reduces the rotation of the motor 212a and outputs it. The position detection unit 212c is an absolute encoder and detects the rotation angle of the motor 212a. A current detection unit 214 is also provided with respect to the motor 212a. The current detection unit 214 detects the current value of the motor 212a.

[0065] The controller 24 drives the motor 212a based on a signal from the operating handle 11. This causes the reduction gear 212b, the engaging projection 213, the drive transmission member 61, and the driven members 44c and 44d to rotate, driving the cables A1 and A2. As a result, the jaw members 43a and 43b are opened and closed. The controller 24 drives the motor 212a so that the opening angle of the jaw members 43a and 43b matches the opening angle (target opening angle) corresponding to the signal from the operating handle 11. Based on the rotation angle detection result of the position detection unit 212c, the controller 24 controls the rotation angle of the motor 212a so that it matches the rotation angle corresponding to the target opening angle. In other words, the controller 24 controls the driving of the jaw members 43a and 43b by the rotation angle of the motor 212a.

[0066] Furthermore, in the following case, for example, it is more effective to control the motor 212a that drives the jaw members 43a and 43b by rotation angle rather than by torque. That is, in order to miniaturize the robot arm 21a around the surgical field so as to secure a working area, it is effective to miniaturize the motor 212a. To miniaturize the motor 212a, it is effective to use a gearbox 212b with a high reduction ratio. However, when the motor 212a is controlled by torque, if a gearbox 212b with a high reduction ratio is used, the behavior of the tip of the surgical instrument 40 is not easily reflected as a change in the torque of the motor 212a. Therefore, it becomes difficult to detect the behavior of the tip of the surgical instrument 40 by detecting a change in the torque of the motor 212a. To solve this problem, it is effective to control the motor 212a that drives the jaw members 43a and 43b by rotation angle.

[0067] Furthermore, by further rotating the motor 212a in the closing direction of the jaw members 43a and 43b from the closed state (i.e., the opening angle is zero), it is possible to generate a closing force (gripping force) using the jaw members 43a and 43b. Hereinafter, the command angle for further closing the jaw members 43a and 43b from the state where the opening angle is zero will be referred to as the closing angle. In this embodiment, the closing angle is a negative value, but it is not limited to negative values. The closing angle is an example of a value corresponding to the rotation angle of the motor 212a and is calculated by the following equation (1). θ = 2 × R p ×R m ×θ m ...(1) Here, θ: Tightening angle Rp: Reduction ratio between the driven members 44c, 44d and the pulleys 43d, 43e of the jaw members 43a, 43b Rm: Reduction ratio of gearbox 212b θ m : Rotation angle of motor 212a That is the case.

[0068] Here, the surgical instrument 40 is cleaned and sterilized after surgery and used multiple times. For this reason, the cables A1 and A2 that drive the jaw members 43a and 43b may stretch during use of the surgical instrument 40. If cables A1 and A2 stretch, even if the motor 212a is controlled to a predetermined rotation angle, the jaw members 43a and 43b cannot be sufficiently closed, and the gripping force of the jaw members 43a and 43b decreases.

[0069] Therefore, in this embodiment, as shown in Figure 11, the controller 24 performs calibration to compensate for the elongation of cables A1 and A2. Specifically, the memory unit 45 stores in advance the closing angle θ1 when a predetermined current value I1 is obtained. The controller 24 obtains the closing angle θ2 when a predetermined current value I1 is obtained, and performs calibration to change the command angle of the closing operation of the jaw members 43a and 43b based on the obtained value θ2 and the value θ1 stored in the memory unit 45. Specifically, the controller 24 corrects the maximum closing angle θ0 based on the closing angle θ1 and the closing angle θ2. The maximum closing angle is the closing angle with the largest absolute value. This allows for calibration to compensate for the elongation of cables A1 and A2 in a configuration where the drive of the jaw members 43a and 43b of the surgical instrument 40 is controlled by the rotation angle of the motor 212a. Therefore, in a configuration where the drive of the jaw members 43a and 43b of the surgical instrument 40 is controlled by the rotation angle of the motor 212a, a decrease in the gripping force of the jaw members 43a and 43b caused by the elongation of cables A1 and A2 can be suppressed. Note that in the graph in Figure 11, the right side is the negative side.

[0070] Furthermore, in this embodiment, the memory unit 45 stores the maximum closing angle θ0 in advance. The maximum closing angle θ0 is an example of a value corresponding to the maximum rotation angle of the motor 212a in the closing direction of the jaw members 43a and 43b. The controller 24 corrects the value θ0 based on the values ​​θ2 and θ1. This corrects the maximum closing angle θ0 of the jaw members 43a and 43b, thereby increasing the maximum rotation angle of the motor 212a that can rotate in the closing direction of the jaw members 43a and 43b. As a result, the decrease in gripping force of the jaw members 43a and 43b caused by the elongation of the cables A1 and A2 can be reliably suppressed.

[0071] Specifically, in this embodiment, the controller 24 corrects the value θ0 by adding the difference Δθ between the value θ2 and the value θ1 to the value θ0. This allows the value θ0 to be corrected simply by adding the difference Δθ between the value θ2 and the value θ1 to the value θ0, thus simplifying the calibration correction process. The controller 24 performs a calibration that changes the value θ0 as the command angle to the value θ0+Δθ.

[0072] More specifically, in this embodiment, the controller 24 corrects the value θ0 so that the jaw members 43a and 43b can be closed up to a closing angle (θ0+Δθ) obtained by adding the difference Δθ between the closing angles of value θ2 and value θ1 to the closing angle of value θ0. This makes it possible to close up the jaw members 43a and 43b to a closing angle obtained by adding the difference Δθ between the closing angles of value θ2 and value θ1 to the closing angle of value θ0 (i.e., the maximum closing angle θ0+Δθ considering the elongation of cables A1 and A2), thereby more reliably suppressing the decrease in gripping force of jaw members 43a and 43b caused by the elongation of cables A1 and A2.

[0073] Here, the calibration principle for compensating for the elongation of cables A1 and A2 in this embodiment will be explained. The memory unit 45 has the value θ1 of the tightening angle when a predetermined current value I1 is obtained, and the maximum tightening angle θ0 stored in advance as initial values. Values ​​θ1 and θ0 are stored in the memory unit 45 by the manufacturer's workers before the surgical instrument 40 is shipped from the manufacturer. At the manufacturer, values ​​θ1 and θ0 are obtained taking into account the initial slack of cables A1 and A2. Value θ0 is set to a value that enables the jaw members 43a and 43b to exert a predetermined gripping force. Note that the absolute value of value θ0 is greater than the absolute value of value θ1.

[0074] The controller 24 starts calibration from the state where the jaw members 43a and 43b are closed (the state where the opening angle of the jaw members 43a and 43b is zero). The controller 24 rotationally drives the motor 212a so that it reaches the maximum clamping angle θ0. Also, while the controller 24 rotates the motor 212a so that the value corresponding to the rotation angle of the motor 212a becomes the value θ0 (using the value θ0 as the target value) and closes the jaw members 43a and 43b, it acquires the value θ2. Here, when the jaw members 43a and 43b are further closed in the closed state, the current value of the motor 212a increases. The current value of the motor 212a is detected (monitored) by the current detection unit 214. When the cables A1 and A2 stretch, even when the clamping angle of the jaw members 43a and 43b becomes the value θ1, the current value of the motor 212a becomes a value smaller than a predetermined current value I1. The controller 24 acquires the clamping angle value θ2 when the current value reaches the predetermined current value I1 based on the detection result of the current value of the motor 212a by the current detection unit 214. Also, the controller 24 calculates the difference Δθ between the value θ2 and the value θ1. The difference Δθ between the value θ2 and the value θ1 corresponds to the elongation due to the use of the cables A1 and A2. Further, the controller 24 corrects the value θ0 so that the jaw members 43a and 43b can be clamped up to the clamping angle θ0 + Δθ, which is obtained by adding the difference Δθ between the value θ2 and the value θ1 to the initial maximum clamping angle value θ0. Thereby, since the initial current response of the motor 212a can be made equivalent to the current response when the cables A1 and A2 of the motor 212a stretch, it is possible to suppress a decrease in the gripping force of the jaw members 43a and 43b caused by the elongation of the cables A1 and A2. Note that the absolute value of the value θ0 is larger than the absolute value of the value θ2.

[0075] Also, in the present embodiment, the controller 24 determines whether or not the value θ2 is within a predetermined range with respect to the value θ1, using a threshold value θ S1Based on this, a determination is made, and if it is determined that value θ2 is within a predetermined range relative to value θ1, value θ0 is not corrected. If it is determined that value θ2 is outside the predetermined range relative to value θ1, value θ0 is corrected. This prevents unnecessary correction of value θ0 when it is determined that value θ2 is within a predetermined range relative to value θ1 (i.e., the elongation of cables A1 and A2 is small and no correction is needed). Also, when it is determined that value θ2 is outside the predetermined range relative to value θ1 (i.e., the elongation of cables A1 and A2 is large and correction is needed), value θ0 can be appropriately corrected.

[0076] Specifically, the controller 24 determines that the value θ2 is equal to the value θ1 ± θ S1 Determine whether it is within the range of threshold θ. S1 While not particularly limited, the value (Y Newtons, etc.) that determines the upper and lower limits of the set gripping force range (X ± Y Newtons, etc.) of the jaw members 43a and 43b can be a value obtained by converting it to a tightening angle using a conversion coefficient. Furthermore, if the set gripping force range differs depending on the type of jaw members 43a and 43b (i.e., the type of end effector 43), the threshold θ can be set for each type of end effector 43. S1 The threshold θ may be different. S1 In this embodiment, this value is positive and is provided in the memory unit 25 located in the robot body 27.

[0077] Furthermore, in this embodiment, the controller 24 determines whether the difference Δθ between value θ2 and value θ1 is within the normal range by setting a threshold θ S2Based on this, a determination is made, and if the difference Δθ between value θ2 and value θ1 is determined to be within the normal range, value θ0 is corrected. If the difference Δθ between value θ2 and value θ1 is determined to be outside the normal range, value θ2 is reacquired. This ensures that calibration is performed appropriately because value θ0 is corrected when the difference Δθ between value θ2 and value θ1 is determined to be within the normal range. Also, if the difference Δθ between value θ2 and value θ1 is determined to be outside the normal range, value θ2 is reacquired, thus avoiding the acquisition of an excessively large value θ2 (and difference Δθ). As a result, it is possible to avoid the value θ0 being corrected to an excessively large value based on an excessively large θ2 (and difference Δθ). This prevents excessive load from being placed on cables A1 and A2 due to the value θ0 being corrected to an excessively large value, thus preventing damage to cables A1 and A2.

[0078] Specifically, the controller 24 determines that the difference Δθ between the value θ2 and the value θ1 is θ S2 Determine whether the value is within the range <Δθ<0. Also determine the threshold θ. S2 While not particularly limited, the threshold value θ can be a common value regardless of the type of end effector 43. S2 In this embodiment, this value is negative and is determined in advance through experiments or other means and stored in the memory unit 25 provided in the robot body 27.

[0079] Furthermore, in this embodiment, the memory unit 45 for storing the value θ1 is provided on the surgical instrument 40. This allows different values ​​θ1 for each surgical instrument 40 to be pre-stored in the memory unit 45 provided on the surgical instrument 40, so that when using the surgical instrument 40, the appropriate value θ1 can be easily used for each surgical instrument 40. In addition, in this embodiment, the memory unit 45 also stores the value θ0. This allows different values ​​θ0 for each surgical instrument 40 to be pre-stored in the memory unit 45 provided on the surgical instrument 40, similar to the value θ1, so that when using the surgical instrument 40, the appropriate value θ0 can be easily used for each surgical instrument 40.

[0080] Furthermore, in this embodiment, the temporary storage unit 26 that stores the correction value (Δθ) based on the values ​​θ2 and θ1 is provided in the robot body 27. As a result, even when the surgical instrument 40 is removed from the robot arm 21a and reattached to the robot arm 21a during surgery, the correction value (Δθ) is stored in the temporary storage unit 26 provided in the robot body 27, so there is no need to reacquire the correction value (Δθ). Consequently, the effort of reacquiring the correction value (Δθ) each time the surgical instrument 40 is attached to the robot arm 21a is eliminated. The correction value (Δθ) stored in the temporary storage unit 26 is reset (deleted) after each surgery (for example, each time the power to the robot body 27 is turned off or restarted). Therefore, it is possible to obtain an appropriate Δθ for each surgery.

[0081] Furthermore, in this embodiment, the controller 24 starts calibration at at least one of the following timings: when the surgical instrument 40 is attached to the robot arm 21a, or when the user interface (such as the operating handle 11 or touch panel 14) that accepts the operation to perform calibration is operated. This means that if calibration is started at the time the surgical instrument 40 is attached to the robot arm 21a, calibration can be performed simply by attaching the surgical instrument 40 to the robot arm 21a, thus saving the user effort. Alternatively, if calibration is started at the time the user operates the user interface that accepts the operation to perform calibration, calibration can be performed at a timing desired by the user. Note that the operating handle 11 or touch panel 14 are examples of user interfaces.

[0082] Furthermore, when calibration is initiated at the time the surgical instrument 40 is attached to the robot arm 21a, the controller 24 determines whether the attachment of the surgical instrument 40 to the robot arm 21a is the first time during the surgery. If the controller 24 determines that the attachment of the surgical instrument 40 to the robot arm 21a is the first time during the surgery, it starts calibration; if it determines that the attachment of the surgical instrument 40 to the robot arm 21a is not the first time during the surgery, it does not start calibration. This ensures that calibration is started appropriately if it is determined that the attachment of the surgical instrument 40 to the robot arm 21a is the first time during the surgery (i.e., calibration has not been performed). Also, if it is determined that the attachment of the surgical instrument 40 to the robot arm 21a is not the first time during the surgery (i.e., calibration has already been performed), calibration is not started, thus avoiding unnecessary calibration.

[0083] When a surgical instrument 40 is attached to the robot arm 21a, the controller 24 retrieves the serial number of the surgical instrument 40 from the memory unit 45 and determines, based on the retrieved serial number, whether or not this is the first time the surgical instrument 40 has been attached to the robot arm 21a during the surgery. Specifically, if the retrieved serial number of the surgical instrument 40 is not stored in the memory unit 25 or the temporary memory unit 26, the controller 24 determines that this is the first time the surgical instrument 40 has been attached to the robot arm 21a during the surgery. The controller 24 also stores the retrieved serial number of the surgical instrument 40 in the memory unit 25 or the temporary memory unit 26. If the retrieved serial number of the surgical instrument 40 is stored in the memory unit 25 or the temporary memory unit 26, the controller 24 determines that this is not the first time the surgical instrument 40 has been attached to the robot arm 21a during the surgery (it is the second time or later). If the controller 24 determines that the attachment of the surgical instrument 40 to the robot arm 21a is not the first time during surgery, it does not start calibration and corrects θ0 using the correction value (Δθ) from the first attachment.

[0084] Furthermore, in this embodiment, the controller 24 has a value θ2, a value θ1, and a value θ corresponding to the rotation angle of the motor 212a which is predetermined according to the number of times the surgical instrument 40 is used. a Based on this, the value θ0 is corrected. This corrects not only the value θ2 and the value θ1, but also the predetermined tightening angle θ according to the number of times the surgical instrument 40 has been used. a Based on this, the value θ0 can be corrected, thereby more reliably suppressing the decrease in gripping force of jaw members 43a and 43b caused by the elongation of cables A1 and A2. a This is a fixed value determined according to the number of times the surgical instrument 40 is used, and is determined in advance through experiments, etc. a This is an example of a fourth value.

[0085] (Control processing during the attachment of surgical instruments) Next, referring to Figure 12, the control process for attaching the surgical instrument 40 to the robot arm 21a will be explained based on a flowchart. Here, we will describe an example where calibration is started at the moment the surgical instrument 40 is attached to the robot arm 21a.

[0086] As shown in Figure 12, first, in step S101, the surgical instrument 40 is attached to the robot arm 21a via the adapter 60. Then, in step S102, the mating operation mode is started. In the mating operation mode, the engaging projection 213 of the robot arm 21a is mated with the engaging recess of the drive transmission member 61 of the adapter 60, and the engaging recess 611 of the drive transmission member 61 of the adapter 60 is mated with the projections 441 and 442 of the driven members 44a to 44d.

[0087] Then, in step S103, it is determined whether or not this is the first time the surgical instrument 40 has been attached to the robot arm 21a during the surgery. If it is determined that this is the first time the surgical instrument 40 has been attached to the robot arm 21a during the surgery, the process proceeds to step S104. In step S104, a calibration mode is started in which calibration is performed. After the processing in step S104 is completed, the process proceeds to step S106. Details of the calibration mode process will be described later.

[0088] Furthermore, if it is determined in step S103 that the attachment of the surgical instrument 40 to the robot arm 21a is not the first time during surgery, the process proceeds to step S105. Then, in step S105, the closing angle correction is performed. In step S105, in the calibration mode for the first attachment described later, θ 0c =θ0+θ a +Δθ(θ 0c The closing angle correction is performed according to the formula for the maximum closing angle after correction. Then, the process proceeds to step S106.

[0089] Then, in step S106, the gripping force check mode is started. In the gripping force check mode, it is determined whether a predetermined gripping force can be output by the jaw members 43a and 43b. If a predetermined gripping force can be output by the jaw members 43a and 43b, the control process is terminated.

[0090] (Calibration mode control process) Next, with reference to Figure 13, the control process for the calibration mode will be explained based on a flowchart.

[0091] As shown in Figure 13, in step S201, the jaw members 43a and 43b are closed. During the closing operation, the jaw members 43a and 43b move θ0+θ a It is driven to be tightened to a tightening angle of +Δθ (where Δθ=0).

[0092] Then, in step S202, the rotation angle of the motor 212a when the current value I1 is obtained. At this time, the current value of the motor 212a is obtained taking into account the friction and inertia of the motor 212a. At this time, the rotation angle of the motor 212a when the predetermined current value I1 detected by the position detection unit 212c is converted into the closing angle of the jaw members 43a and 43b by the above equation (1), thereby obtaining the closing angle value θ2.

[0093] Then, in the first step S203, whether the value θ2 is within a predetermined range relative to the value θ1 is determined by the threshold θ S1 It is determined based on the following. Specifically, the value θ2 is θ1-θ S1 ≤θ2-Δθ≦θ1+θ S1 It is determined whether the value θ2 is within the range (where Δθ=0). If it is determined that the value θ2 is within a predetermined range relative to the value θ1, it is determined that the elongation of cables A1 and A2 is small and no correction is necessary, so the control process is terminated without correction. In this case, θ0, which is stored in the memory unit 45 beforehand, is used as the maximum tightening angle.

[0094] Furthermore, if it is determined in the first step S203 that the value θ2 is not within a predetermined range relative to the value θ1, it can be determined that the cables A1 and A2 have stretched significantly and require correction, so the process proceeds to step S204.

[0095] Then, in step S204, the difference Δθ between the value θ2 and the value θ1 is obtained as a correction value.

[0096] Then, in step S205, whether the difference Δθ is within the normal range is determined by the threshold θ S2 The determination is made based on the following: Specifically, the difference Δθ is θ S2 It is determined whether the difference Δθ is within the range < 0. If it is determined that the difference Δθ is within the normal range, the process proceeds to step S207.

[0097] Then, in step S207, a closing angle correction is performed to correct the value θ0 based on the values ​​θ1 and θ2. Specifically, the value θ0 is corrected by adding the difference Δθ between the values ​​θ1 and θ2 to the value θ0. More specifically, θ 0c =θ0+θ a +Δθ(θ 0c The maximum tightening angle is corrected as shown by the formula (where is the corrected maximum tightening angle).

[0098] Then, in step S208, the jaw members 43a and 43b are re-closed. During the re-closed operation, the jaw members 43a and 43b are closed to the corrected maximum closing angle θ. 0c It is driven to close all the way. Then, the process proceeds to step S202. In step S202, the closing angle θ2 at which a predetermined current value I1 is obtained again.

[0099] Then, in the second step S203, which follows step S208, θ2-Δθ (where Δθ=θ2-θ1) becomes θ1-θ S1 ≤θ2-Δθ≦θ1+θ S1 It is determined whether or not it is within the range. Here, θ2-Δθ is θ2-θ2+θ1, which is θ1. Therefore, in step S203, θ2-Δθ is θ1-θ S1 ≤θ2-Δθ≦θ1+θ S1 The control process is terminated after it is determined that the result falls within the specified range and the correction has been applied.

[0100] Furthermore, if it is determined in step S205 that the difference Δθ is not within the normal range, the process proceeds to step S209.

[0101] Then, in step S209, it is determined whether the difference Δθ has been determined to be outside the normal range for two consecutive times. If it is determined that the difference Δθ has not been determined to be outside the normal range for two consecutive times, the process proceeds to step S201. Then, the processing in steps S201 to S205 is repeated. If it is determined that the difference Δθ has not been determined to be outside the normal range for two consecutive times, the process proceeds to step S210. Then, in step S210, an error is displayed and the control process ends.

[0102] (modified version) It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than by the description of the embodiments above, and further includes all modifications (exceptions) within the meaning and scope equivalent to the claims.

[0103] For example, in the above embodiment, an example was shown where the values ​​corresponding to the motor rotation angle (θ1, θ2, θ0, etc.) represent the closing angle of the jaw member, but the present invention is not limited to this. In the present invention, the values ​​corresponding to the motor rotation angle may represent values ​​other than the closing angle of the jaw member. For example, the values ​​corresponding to the motor rotation angle may be the motor rotation angle itself.

[0104] Furthermore, in the above embodiment, an example was shown where the third value (θ0) corresponds to the maximum rotation angle of the motor in the closing direction of the jaw member, but the present invention is not limited to this. In the present invention, the third value may be a value that has a larger absolute value than the value θ1 and corresponds to a rotation angle other than the maximum rotation angle of the motor in the closing direction of the jaw member.

[0105] Furthermore, while the above embodiment shows an example of determining whether the difference (Δθ) between the second value (θ2) and the first value (θ1) is within the normal range, the present invention is not limited to this. In the present invention, it is not necessary to determine whether the difference between the second value and the first value is within the normal range.

[0106] Furthermore, although the above embodiment shows an example of determining whether the second value (θ2) is within a predetermined range with respect to the first value (θ1), the present invention is not limited to this. In the present invention, it is not necessary to determine whether the second value is within a predetermined range with respect to the first value.

[0107] Furthermore, in the above embodiment, an example was shown in which a first storage unit (45) for storing a first value (θ1) and a third value (θ0) is provided in the surgical instrument, and a second storage unit (26) for storing a second value (θ2) and a correction value (Δθ) based on the first value is provided in the robot body. However, the present invention is not limited to this. In the present invention, the first storage unit may be provided in the robot body, or the second storage unit may be provided in the surgical instrument. Also, the second storage unit does not have to be a temporary storage unit.

[0108] Furthermore, while the above embodiment shows an example of determining whether or not the attachment of a surgical instrument to the robot arm is the first time during surgery, the present invention is not limited thereto. In the present invention, calibration may be started each time a surgical instrument is attached to the robot arm.

[0109] Furthermore, in the above embodiment, the second value (θ2), the first value (θ1), and the fourth value (θ a An example of correcting the third value (θ0) based on ) has been shown, but the present invention is not limited to this. In the present invention, the correction of the third value (θ0) is performed using the fourth value (θ a You do not need to use ).

[0110] Furthermore, the above embodiment shows an example in which the drive of the jaw member of a surgical instrument is controlled by the rotation angle of a motor, thereby suppressing a decrease in the gripping force of the jaw member caused by cable elongation, but the present invention is not limited to this. In the present invention, a rod may be used as the elongated element, and gears, pulleys, and bearings may be used as the driven members, and a decrease in the gripping force of the jaw member caused by wear, seizure, galling, chipping, rust, etc. of the gears, pulleys, bearings, and rods of the surgical instrument may be compensated for. In addition, the present invention may compensate for a decrease in gripping force due to wear of the jaw member.

[0111] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0112] Furthermore, in the above embodiment, an example was shown in which the third value (θ0) as the command angle is corrected based on the second value (θ2) and the first value (θ1), but the modified example shown in Figure 14 may also be used. In the modified example shown in Figure 14, the controller 24 performs calibration by changing the command angle of the closing operation of the jaw members 43a and 43b without correcting the value θ0, based on the value θ2 and the difference Δθ2 between the value θ1 and the value θ0. In the modified example shown in Figure 14, the value θ1 and the difference Δθ2 between the value θ1 and the value θ0 are stored in the storage unit 45 in advance. During calibration, the controller 24 acquires the value θ2 while closing the jaw members 43a and 43b by rotating the motor 212a so that the value corresponding to the rotation angle of the motor 212a becomes the value θ1 + Δθ2 (with the value θ1 + Δθ2 as the target value). The controller 24 also adds the difference Δθ2 to the value θ2. As a result, the controller 24 performs a calibration that changes the command angle value θ1 + Δθ2 to the value θ2 + Δθ2. The jaw members 43a and 43b can then be tightened up to a tightening angle equal to the difference Δθ2 added to the value θ2.

[0113] Figure 15 also shows another modified example using the difference Δθ2. In this example, the value θ0 and the difference Δθ2 between value θ1 and value θ0 are pre-stored in the memory unit 45. During calibration, the controller 24 rotates the motor 212a so that the value corresponding to the rotation angle of the motor 212a becomes value θ0 (with value θ0 as the target value), and while closing the jaw members 43a and 43b, it acquires the value θ2. The controller 24 also adds the difference Δθ2 to the value θ2. As a result, the controller 24 performs calibration to change the value θ0 as the command angle to the value θ2 + Δθ2. The jaw members 43a and 43b can be closed up to the closing angle obtained by adding the difference Δθ2 to the value θ2. [Explanation of symbols]

[0114] 21a: Robot arm, 24: Controller (control unit), 26: Temporary memory unit (second memory unit), 27: Robot body, 40: Surgical instruments, 43a, 43b: Jaw members, 45: Memory unit (first memory unit), 100: Robot surgical system, 212a: Motor, A1, A2: Cable (elongated element), I1: Determined current value, θ0: Value (third value), θ1: Value (first value), θ2: Value (second value), θ a : value (fourth value), θ S1 : threshold (second threshold), θ S2 :Threshold (first threshold), Δθ:Difference

Claims

1. A surgical instrument including a pair of jaw members that open and close with an elongated element, A robotic arm to which the surgical instrument is attached includes a motor that drives the elongated element, A first storage unit that pre-stores a first value that is proportional to a predetermined ratio to the rotation angle of the motor when a predetermined current value is obtained, The system includes a control unit that performs calibration, which acquires a second value proportional to the rotation angle of the motor when the current reaches a predetermined value, in a predetermined ratio, and when the acquired second value differs from the first value, it changes the command angle for the closing operation of the jaw member based on the first value and the second value. A robotic surgical system in which the command angle for the closing operation of the pair of jaw members is an angle proportional by a predetermined ratio to the rotation angle commanded to the motor when the control unit causes the motor to rotate in a way that further closes the pair of jaw members, generating a closing force on the pair of jaw members from a state where the opening angle of the pair of jaw members is zero.

2. The robotic surgical system according to claim 1, wherein the control unit corrects a third value proportional to the rotation angle of the motor in the closing direction of the pair of jaw members in a predetermined ratio, based on the second value and the first value.

3. The first storage unit pre-stores the third value which is proportional to the maximum rotation angle of the motor in the closing direction of the pair of jaw members at a predetermined ratio. The robotic surgical system according to claim 2, wherein the control unit corrects the third value based on the second value and the first value.

4. The robotic surgical system according to claim 3, wherein the control unit corrects the third value by adding the difference between the second value and the first value to the third value.

5. The robotic surgical system according to any one of claims 2 to 4, wherein the first value, the second value, and the third value are values ​​representing a clamping angle that is proportional in a predetermined ratio to the rotation angle of the motor when generating a clamping force on the pair of jaw members.

6. The third value is a value representing the maximum closing angle that is proportional to the maximum rotation angle of the motor in the closing direction of the pair of jaw members at the predetermined ratio. The robotic surgical system according to claim 5, wherein the control unit corrects the value of 3 so that the pair of jaw members can be closed to a closing angle obtained by adding the difference in the closing angle between the second value and the first value to the closing angle of the third value.

7. The robotic surgical system according to any one of claims 2 to 6, wherein the control unit determines, based on a first threshold, whether the difference between the second value and the first value is within the normal range, corrects the third value if it determines that the difference between the second value and the first value is outside the normal range, and reacquires the second value if it determines that the difference between the second value and the first value is outside the normal range.

8. The robotic surgical system according to any one of claims 2 to 6, wherein the control unit determines, based on a second threshold value, whether the second value is within a predetermined range relative to the first value, and if it determines that the second value is within a predetermined range relative to the first value, it does not correct the third value, and if it determines that the second value is outside a predetermined range relative to the first value, it corrects the third value.

9. The robotic surgical system according to any one of claims 1 to 8, wherein the first memory unit is provided in the surgical instrument.

10. The robot body on which the robot arm is provided, The system further includes a second storage unit that stores a correction value for changing the command angle, which is a value based on the second value and the first value. The robotic surgical system according to any one of claims 1 to 9, wherein the second memory unit is provided in the robot body.

11. The robotic surgical system according to any one of claims 1 to 10, wherein the control unit starts the calibration at at least one of the following timings: the timing at which the surgical instrument is attached to the robotic arm, and the timing at which the user interface that accepts the operation to perform the calibration is operated.

12. The robotic surgical system according to claim 11, wherein the control unit determines whether the attachment of the surgical instrument to the robot arm is the first time since the power was turned on, and if it determines that the attachment of the surgical instrument to the robot arm is the first time, it starts the calibration, and if it determines that the attachment of the surgical instrument to the robot arm is not the first time, it does not start the calibration.

13. The robotic surgical system according to claim 2, wherein the control unit corrects the third value based on the second value, the first value, and a fourth value which is proportional in a predetermined ratio to the rotation angle of the motor, which is predetermined according to the number of times the surgical instrument is used.

14. The robotic surgical system according to any one of claims 1 to 13, wherein the elongated element is a cable.

15. The robotic surgical system according to claim 2, wherein the absolute value of the third value is greater than the absolute value of the first value.

16. The robotic surgical system according to any one of claims 1 to 15, wherein the control unit starts the calibration from an angle proportional to the rotation angle of the motor in a predetermined ratio corresponding to the closed state of the pair of jaw members.

17. The robotic surgical system according to claim 2, wherein the control unit acquires the second value while the jaw member is closed by rotating the motor so that the value proportional to the rotation angle of the motor in a predetermined ratio is the third value.

18. A calibration method performed by the control unit of a robotic surgical system, comprising: a surgical instrument including a pair of jaw members that open and close by an elongated element; a robotic arm to which the surgical instrument is attached, including a motor that drives the elongated element; a storage unit that stores in advance a first value that is proportional in a predetermined ratio to the rotation angle of the motor when a predetermined current value is obtained; and a control unit, the method being performed by the control unit of the robotic surgical system, A step of obtaining a second value that is proportional to the rotation angle of the motor when the predetermined current value is obtained, in a predetermined ratio, The procedure includes a step of performing calibration, in which, when the acquired second value and the first value are different, the command angle of the closing operation of the jaw member is changed based on the first value and the second value, A calibration method in which the command angle for the closing operation of the pair of jaw members is an angle proportional by a predetermined ratio to the rotation angle commanded to the motor when the control unit causes the motor to rotate in the closing direction to generate a closing force on the pair of jaw members from a state where the opening angle of the pair of jaw members is zero.

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