Surgical robot and control unit of surgical robot

Abstract

A surgical robot includes a master unit, a master control unit, a slave unit, and a slave control unit. The slave control unit is configured to calculate a slave control value for controlling the surgical instrument on the basis of a target state of the surgical instrument operated on the basis of the operation received by the master device unit and a state of the surgical instrument, and to control the slave device unit on the basis of the slave control value. The master control unit is configured to calculate a master control value for controlling the reaction force on the basis of the surgical instrument state, the target state, and the slave control value acquired from the slave control unit, and to control the master device unit on the basis of the master control value.

Description

Technical Field

[0001] The present disclosure relates to a master-slave surgical robot. Background Art

[0002] The master-slave surgical robot receives operations from medical personnel such as doctors (hereinafter referred to as users) at the master device, and uses instruments used for surgery such as forceps and scalpels as slave devices. Then, the slave device is controlled according to the operations received at the master device, so as to perform surgery on the patient (hereinafter referred to as the subject). In addition, in the above-mentioned surgical robots, the following technology is known: through bidirectional control, the force exerted on the surgical instrument during the operation is fed back from the slave device to the master device, thereby providing force feedback to the user (for example, Patent Document 1).

[0003] In the master device and slave device of the surgical robot that performs force feedback, proportional control is performed. In order to improve the sensitivity of force feedback, it is conceivable to increase the gain of the proportional control of the master device.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 7049069 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, excessively increasing the proportional control gain of the master device may make it difficult to control the surgical instrument, for example, if there is slack in the wire used to transmit the driving force to the surgical instrument, a gap between the surgical instrument and the transmission mechanism for the driving force, or a control delay occurs. Therefore, there is a limit to the increase in the proportional control gain.

[0009] In one aspect of the present disclosure, it is desired to increase the sensitivity of force feedback.

[0010] Solutions to the problem

[0011] One scheme of the present disclosure is a surgical robot, which includes a main device unit, a main control unit, a slave device unit, a slave control unit, and a slave device detection unit. The main device unit is configured to accept an operation from a user and apply a reaction force to the user who performs the operation. The main control unit is configured to control the main device unit and generate a reaction force. The slave device unit operates a surgical instrument. The slave control unit is configured to control the slave device unit and operate the surgical instrument based on a target state, wherein the target state is the state of the surgical instrument that moves based on the operation accepted by the main device unit. The slave device detection unit is configured to detect the state of the surgical instrument, wherein the state of the surgical instrument is the state of the surgical instrument. The slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on the state of the surgical instrument and the target state, and control the slave device unit based on the slave control value. The main control unit is configured to calculate a master control value for controlling the reaction force based on the state of the surgical instrument, the target state, and the slave control value obtained from the slave control unit, and control the main device unit based on the master control value.

[0012] According to the above configuration, the master control is calculated with reference to the slave control value, and the reaction force on the user is controlled by the master control. Thus, changes in the slave control value can be quickly reflected in the master control value, resulting in increased sensitivity of force feedback.

[0013] In one aspect of the present disclosure, the slave control unit may be configured to calculate the slave control value by performing integration based on the surgical instrument state and the target state.

[0014] According to the above configuration, disturbances in the slave control unit (in other words, steady-state deviations) can be suppressed, so that the slave controlled value can be calculated with higher accuracy.

[0015] In one embodiment of the present disclosure, the slave control unit may be configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on the difference between the state of the surgical instrument and the target state. The master control unit may be configured to calculate the master control value by proportional control, wherein the proportional control is performed based on the difference between the state of the surgical instrument and the target state. The gain of the proportional control in the master control unit may be greater than the gain of the proportional control in the slave control unit.

[0016] According to the above configuration, the sensitivity of force feedback can be improved.

[0017] In one embodiment of the present disclosure, the main control unit may be configured to calculate the main control value by proportional control, wherein the proportional control is performed based on the difference between the state of the surgical instrument and the target state. The surgical robot may also include a display unit and a receiving unit. The display unit is configured to display the gain of the proportional control. The receiving unit is configured to receive an operation for changing the gain of the proportional control.

[0018] According to the above configuration, the sensitivity of force feedback can be adjusted.

[0019] In one embodiment of the present disclosure, the slave control unit may be configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on the difference between the state of the surgical instrument and the target state. The surgical robot may also include a display unit and a receiving unit. The display unit is configured to display the gain of the proportional control. The receiving unit is configured to receive an operation for changing the gain of the proportional control.

[0020] According to the above configuration, customization can be performed so that the surgical instrument can be controlled more appropriately.

[0021] In one embodiment of the present disclosure, the slave control unit may be configured to calculate the slave control value by further performing integral control, wherein the integral control is performed based on the difference between the state of the surgical instrument and the target state. The display unit may be configured to further display the gain of the integral control. The receiving unit may be configured to further receive an operation for changing the gain of the integral control.

[0022] According to the above configuration, customization can be performed so that the surgical instrument can be controlled more appropriately.

[0023] One scheme of the present disclosure is a control unit of a surgical robot, which includes a main control unit and a slave control unit. The main control unit is configured to control the main equipment unit and generate a reaction force, wherein the main equipment unit is configured to accept an operation from a user and apply a reaction force to the user who performs the operation. The slave control unit is configured to control the slave equipment unit and operate the surgical instrument based on a target state, wherein the target state is the state of the surgical instrument that moves based on the operation accepted by the main equipment unit, and the slave equipment unit operates the surgical instrument. In addition, the slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on the state of the surgical instrument and the target state, and control the slave equipment unit based on the slave control value, wherein the state of the surgical instrument is the state of the surgical instrument detected by the slave equipment detection unit. The main control unit is configured to calculate a master control value for controlling the reaction force based on the state of the surgical instrument, the target state, and the slave control value obtained from the slave control unit, and control the main equipment unit based on the master control value.

[0024] According to the above configuration, the master control is calculated with reference to the slave control value, and the reaction force on the user is controlled by the master control. Thus, changes in the slave control value can be quickly reflected in the master control value, resulting in increased sensitivity of force feedback. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is an illustration of a surgical robot.

[0026] Figure 2 It is a block diagram of the surgical robot.

[0027] Figure 3 This is an illustration of a master / slave modeled as a single degree of freedom system.

[0028] Figure 4 It is a frame diagram of asymmetric side bidirectional control.

[0029] Figure 5 This is an illustration of the gain setting screen.

[0030] Description of Reference Numerals

[0031] 1…surgical robot: 2…robot arm; 20…connecting part; 21…arm part; 22…joint part;

[0032] 23-25 ​​... 1st drive unit to 3rd drive unit; 26 ... sensor unit; 3 ... control unit;

[0033] 30 ... main control unit; 31 ... slave control unit; 32 ... gain adjustment unit; 33 ... storage device;

[0034] 4 ... operating unit; 40 ... operating device; 41 ... position operating part; 41A ... movable part;

[0035] 41B...driving unit; 42...gripping operation unit; 42A...movable unit; 42B...driving unit;

[0036] 43 ...display unit; 44 ...receiving unit; 5 ...surgical instrument; 50 ...gripping unit;

[0037] 50A...sensor unit; 51...opening and closing mechanism; 52...wrist unit; 52A...sensor unit;

[0038] 53 ... axis; 54 ... adapter; 6 ... trocar; 7 ... setting screen; 70 to 75 ... display area;

[0039] 76…Cursor. DETAILED DESCRIPTION

[0040] The following describes the embodiments of the present disclosure with reference to the accompanying drawings. In addition, the embodiments of the present disclosure are not limited to the following embodiments, and various embodiments can be adopted within the technical scope of the present disclosure.

[0041] [1. Summary]

[0042] The surgical robot 1 of the present embodiment includes two robot arms 2 having the same structure, a control unit 3, and an operation unit 4 (see Figure 1 , Figure 2 ). In addition, each robot arm 2 is equipped with a surgical instrument 5. In addition, the number of the robot arms 2 can be one or more than three.

[0043] The surgical robot 1 is configured as a master-slave robot system. The surgical robot 1 operates the robot arm 2 and the surgical instrument 5 (in other words, the slave device) in response to the user's operation of the operating part of the operating unit 4 (in other words, the master device), thereby operating the subject. In addition, the surgical robot 1 is configured to provide force feedback. The details will be described below. The surgical robot 1 is configured to allow the user to feel the force exerted on the surgical instrument that moves in accordance with the user's operation through the operating part of the operating unit 4.

[0044] [2.Surgical instruments]

[0045] The surgical instrument 5 is configured to insert the front end of the surgical instrument 5 into the body of the subject through the puncture device 6 which punctures the abdomen of the subject, and to perform treatment by moving the part provided at the front end in the body (see Figure 1 ). In the present embodiment, as an example, forceps are used as the surgical instrument 5. However, the present disclosure is not limited thereto, and a surgical instrument other than forceps, such as a scalpel, may also be used.

[0046] The surgical instrument 5 includes a grip 50, an opening and closing mechanism 51, a wrist 52, a shaft 53, and an adapter 54 (see Figure 1 , Figure 2 ).

[0047] The shaft 53 is an elongated cylindrical portion, and an adapter 54 is provided at the end portion of the shaft 53 on the opposite side to the front end.

[0048] The gripping portion 50 is provided at the front end of the shaft 53 and is inserted into the body of the subject via the trocar 6, so as to perform treatment such as gripping the body tissue of the subject. The gripping portion 50 comprises a first portion, a second portion, and an opening and closing mechanism 51, and the opening and closing mechanism 51 is configured to move the first portion and the second portion closer to and further away from each other (hereinafter also referred to as an opening and closing action). By moving the first portion and the second portion closer to each other, an object is gripped, and by moving the first portion and the second portion further away from each other, the gripped object is released.

[0049] In addition, the grip portion 50 also includes a sensor portion 50A (see Figure 2 ), the sensor portion 50A is used to detect the state of the opening and closing action (hereinafter referred to as the opening and closing state). Specifically, for example, the sensor portion 50A can detect the distance between the first part and the second part and / or the angle between the first part and the second part as the opening and closing state.

[0050] The wrist 52 is provided on the shaft 53 at a position close to the grip 50, and the wrist 52 can rotate at at least one position, and by rotating at the position, the direction (in other words, the posture) of the grip 50 is changed. In addition, the wrist 52 has a sensor part 52A for detecting the direction of the grip 50.

[0051] In addition, the sensor units 50A and 52A output sensor signals indicating detection results to the control unit 3 .

[0052] A plurality of wires are provided inside the cylindrical shaft 53 , and the plurality of wires are used to transmit driving force to the grip 50 and the wrist 52 to operate the above parts.

[0053] [3.Robot arm]

[0054] The robot arm 2 is configured to hold the surgical instrument 5 mounted at its front end at a predetermined position and to change the posture of the robot arm 2 according to the operation of the user, thereby adjusting the position and direction (in other words, the posture) of the surgical instrument 5 (see Figure 1 ).

[0055] A connection portion 20 that can be attached to or detached from an adapter 54 of a surgical instrument 5 is provided at the front end of the robot arm 2, and the surgical instrument 5 is installed via the connection portion 20. Various types of forceps and surgical instruments other than forceps can be installed on the connection portion 20 of the robot arm 2.

[0056] The robot arm 2 is configured as a link mechanism and includes a plurality of arms 21 and a plurality of joints 22 (in other words, joints) provided at the ends of the arms 21 for rotating the respective arms 21. In addition, each arm 21 is connected to other arms 21 via the joints 22.

[0057] In addition, the robot arm 2 includes a first drive unit 23 to a third drive unit 25 (see Figure 2 ). In addition, each of the first to third driving parts 23 to 25 may include, for example, at least one pneumatic actuator or at least one motor.

[0058] The first drive unit 23 is configured to drive each joint 22 according to the user's operation, and the driving force generated by the first drive unit 23 is transmitted to each joint 22 via a transmission mechanism including a plurality of wires and a plurality of pulleys. By driving each joint 22 by the first drive unit 23, each arm 21 is displaced, the posture of the robot arm 2 is changed, and the direction and position of the surgical instrument 5 are also changed.

[0059] The second drive unit 24 drives the wrist 52 of the surgical instrument 5 according to the user's operation, and the driving force generated by the second drive unit 24 is transmitted to the wrist 52 via the transmission mechanism. When the second drive unit 24 drives the wrist 52, the direction of the grip 50 changes.

[0060] In addition, the third drive unit 25 is configured to drive the opening and closing mechanism 51 of the surgical instrument 5 according to the user's operation, and the driving force generated by the third drive unit 25 is transmitted to the opening and closing mechanism 51 via the transmission mechanism. When the third drive unit 25 drives the opening and closing mechanism 51, the opening and closing state of the grip 50 changes.

[0061] In addition, the robot arm 2 includes a sensor unit 26 for detecting the posture of the robot arm 2. The sensor unit 26 can detect, for example, the angle at which each joint unit 22 is rotated, or can detect the state (for example, the pressure of compressed air, etc.) of the first drive unit 23 that drives each joint unit 22. In addition, the sensor unit 26 outputs a sensor signal indicating the detection result to the control unit 3.

[0062] [4. Operation unit]

[0063] The operation unit 4 is configured to accept the user's operation of the robot arm 2 and the surgical instrument 5, and includes two operation devices 40 provided corresponding to each robot arm 2, a display unit 43, and a reception unit 44 (see Figure 2 ). In addition, each operating device 40 includes a position operating unit 41 and a grip operating unit 42.

[0064] The position operation unit 41 receives an operation for adjusting the position and direction of the grip 50 of the surgical instrument 5 mounted on the robot arm 2, and the robot arm 2 corresponds to the operating device 40 provided with the position operation unit 41. That is, the posture of the robot arm 2 is changed in response to the operation of the position operation unit 41 to adjust the position and direction of the surgical instrument 5, or the wrist 52 of the surgical instrument 5 is operated to adjust the direction of the grip 50.

[0065] The grip operation unit 42 receives an operation for causing the grip 50 of the surgical instrument 5 mounted on the robot arm 2 to perform an opening and closing operation. The robot arm 2 corresponds to the operating device 40 provided with the grip operation unit 42 .

[0066] Then, the operation device 40 outputs an operation signal indicating the contents of the operation accepted by the position operation unit 41 and the grip operation unit 42 to the control unit 3 .

[0067] As described above, the surgical robot 1 is configured to provide force feedback. Therefore, the surgical instrument 5 moves according to the user's operation, whereby the surgical instrument 5 receives force from the subject, etc., and a reaction force corresponding to the force is applied to the user through the position operation unit 41 and the grip operation unit 42 .

[0068] Specifically, the position operation unit 41 and the grip operation unit 42 are respectively provided with movable parts 41A, 42A and driving parts 41B, 42B. The driving parts 41B, 42B drive the movable parts 41A, 42A, for example, by means of a pneumatic actuator or a motor. Moreover, the driving part 41B of the position operation unit 41 displaces the movable part 41A according to the control signal input from the control unit 3, thereby applying a reaction force to the user who is operating the position operation unit 41. Similarly, the driving part 42B of the grip operation unit 42 displaces the movable part 42A according to the control signal input from the control unit 3, thereby applying a reaction force to the user who is operating the grip operation unit 42.

[0069] As an example, the display unit 43 is configured as a liquid crystal display, and the display unit 43 operates according to a control signal from the control unit 3 to display, for example, a setting screen, an endoscopic image of the subject, the status of the robot arm 2 and the surgical instrument 5, or information required for operating the surgical robot 1. In addition, the endoscopic image may be, for example, an image of the inside of the patient's body cavity acquired by an endoscope inserted into the patient's body cavity via another puncture device puncturing the patient's abdomen, etc. In addition, the endoscope may be held by another robot arm or an endoscope holding device not shown.

[0070] The accepting unit 44 is a device that accepts an operation from a user or the like, and includes, for example, a keyboard, a mouse, a touch panel, or a foot switch, etc. The accepting unit 44 outputs an operation signal indicating the content of the accepted operation to the control unit 3 .

[0071] [5. Control unit]

[0072] [(1) Overall composition]

[0073] The control unit 3 is configured to control each robot arm 2, surgical instrument 5, and operation unit 4 (see Figure 2 The control unit 3 is constituted as a computer system including a processor, a ROM (read only memory), a RAM (random access memory), a bus, and an input / output unit. The functions of the control unit 3 are realized by the processor operating according to the program stored in the ROM or RAM. In addition, part or all of the functions realized by the processor can also be realized by hardware such as at least one IC (integrated circuit).

[0074] The control unit 3 includes a main control unit 30 , a sub-control unit 31 , a gain adjustment unit 32 , and a storage device 33 .

[0075] The storage device 33 is a nonvolatile storage medium such as a hard disk or a flash memory, and stores therein programs necessary for processing by the control unit 3 , setting information related to the operation of the surgical robot 1 , and the like.

[0076] On the other hand, the functions of the master control unit 30 and the slave control unit 31 are realized by the operation of the processor. The master control unit 30 is configured to control the operation unit 4, and the slave control unit 31 is configured to control each robot arm 2 and the surgical instrument 5 mounted on each robot arm 2. In addition, as will be described in detail below, the master control unit 30 and the slave control unit 31 calculate the driving force τm (in other words, the master control value) of the master device and the driving force τs (in other words, the slave control value) of the slave device by performing master control and slave control.

[0077] The driving force τm of the master device refers to the driving force of the driving parts 41B and 42B of the position operating part 41 and the grip operating part 42 in each operating device 40 of the operating unit 4. The driving force τs of the slave device refers to the driving force of the first to third driving parts 23 to 25 in each robot arm 2.

[0078] The main control unit 30 outputs control signals to the drive units 41B and 42B of the position operation unit 41 and the grip operation unit 42 , and controls the drive units 41B and 42B to operate the movable units 41A and 42A with the drive force τm, respectively, thereby generating a reaction force.

[0079] Furthermore, the main control section 30 detects the operation performed by the user on the position operation section 41 and the grip operation section 42 based on the operation signal from the operation unit 4. Then, the main control section 30 identifies the target state (in other words, Xm) based on the detected operation, which is the state regarding the current position and direction of the grip section 50 and the opening and closing action. In addition, the target state and Xm are described in detail below.

[0080] On the other hand, the control unit 31 outputs control signals to the first drive unit 23 to the third drive unit 25 of the robot arm 2. Thus, the control unit 31 controls the first drive unit 23 and the second drive unit 24 so that the first drive unit 23 and the second drive unit 24 operate the plurality of joints 22 and the wrist 52 with the driving force τs. In addition, the control unit 31 controls the third drive unit 25 so that the third drive unit 25 operates the opening and closing mechanism 51 with the driving force τs.

[0081] In addition, the slave control unit 31 recognizes the current state of the opening and closing action of the grip 50 as the surgical instrument state (in other words, Xs) based on the sensor signal from the sensor unit 50A provided on the grip 50 of the surgical instrument 5. In addition, the slave control unit 31 recognizes the current position and direction of the grip 50 as the surgical instrument state (in other words, Xs) based on the sensor signal from the sensor unit 52A provided on the wrist 52 of the surgical instrument 5 and the sensor signal from the sensor unit 26 provided on the robot arm 2. In addition, the surgical instrument state and Xs will be described in detail below.

[0082] [(2) Asymmetric bidirectional control]

[0083] The master / slave devices of this embodiment can be modeled as follows Figure 3 The single degree of freedom system shown in the figure. At this time, the dynamics of the master and slave devices are expressed by the following mathematical formula:

[0084] [Mathematical formula 1]

[0085]

[0086] [Mathematical formula 2]

[0087]

[0088] Here, in the control of the position and direction of the grip 50, the position operation unit 41 for operation corresponds to the master device, and the grip 50 corresponds to the slave device. In addition, in the control of the opening and closing action of the grip 50, the grip operation unit 42 for operation corresponds to the master device, and the grip 50 corresponds to the slave device.

[0089] In addition, Xm represents the state that the slave device should reach (in other words, the target state of the slave device), which is determined based on the current state of the master device determined by the operation from the user. More specifically, the target values ​​of the position and direction of the holding portion 50 and the target values ​​of the open and closed state can correspond to the target state. In addition, Mm represents the mass of the master device, Dm represents the viscous friction coefficient of the damper on the master device side, and Fm represents the external force applied to the master device by the user's operation. In addition, as described above, τm represents the driving force when the driving portion operates the movable portion in order to generate a reaction force in the position operating portion 41 and the holding operating portion 42.

[0090] In addition, Xs represents the current state of the slave device (in other words, the surgical instrument state). More specifically, the value representing the current position and direction of the grip 50, and the value representing the current open and closed state of the grip 50 correspond to the surgical instrument state. In addition, Ms represents the mass of the slave device, Ds represents the viscous friction coefficient of the damper on the slave device side, and Fs represents the external force applied to the slave device by the subject during the operation. In addition, as described above, τs represents the driving force when the first drive unit 23 and the second drive unit 24 operate the joint unit 22 and the wrist 52 in order to make the position and direction of the grip 50 reach the target state. In addition, τs represents the driving force when the third drive unit 25 operates the opening and closing mechanism 51 in order to make the open and closed state of the grip 50 reach the target state.

[0091] Furthermore, the main control unit 30 and the slave control unit 31 execute the following Figure 4 The asymmetric bidirectional control is shown in the block diagram of FIG. In this control, the difference of Xm minus Xs is calculated at the summing point 3A, and the difference is input to the transmission element 3B. Then, based on the difference, the transmission element 3B calculates the driving force τs of the slave device through proportional control and integral control, and outputs the driving force τs to the transmission element 3C representing the slave device and the summing point 3E. The transmission element 3C outputs Xs to the summing point 3A.

[0092] Furthermore, the difference between Xm and Xs calculated at the summing point 3A is input to the transfer element 3D that performs proportional control, and the transfer element 3D calculates τm' by proportional control based on the difference, and outputs τm' to the summing point 3E. At the summing point 3E, the driving force τm of the master device is calculated by subtracting the driving force τs of the slave device from τm', and the driving force τm is output to the transfer element 3F that represents the master device. The transfer element 3F outputs Xm to the summing point 3A.

[0093] In addition, the transmission element 3B performs proportional control with Kps as a gain and integral control with Kis as a gain, corresponding to the processing in the slave control unit 31. In addition, the transmission element 3D and the summing point 3E perform proportional control with -Kpm as a gain at the transmission element 3D, corresponding to the processing in the master control unit 30.

[0094] That is, the main control unit 30 calculates the driving force τm of the master device based on Xm, Xs, and the driving force τs of the slave device obtained from the slave control unit 31. In addition, the absolute value of -Kpm (hereinafter referred to as |Kpm|) is greater than the absolute value of Kps (hereinafter referred to as |Kps|). More specifically, as an example, |Kpm| may be more than two times and less than three times |Kps|. However, it is not limited to this, and |Kpm| and |Kps| may be appropriately set. In addition, for example, |Kpm| may be less than |Kps|.

[0095] In addition, the scaled driving force τm may be input to the transmission element 3F representing the master device. In addition, scaling refers to multiplying the driving force τm of the master device by a coefficient having a predetermined value greater than 1. Through the above-mentioned scaling, a reaction force greater than the force received from the device can be applied to the user, so that the user can appropriately treat a tiny part in the body of the subject or perform precise treatment.

[0096] Figure 3 The box-line diagram of is represented by the following mathematical equations (3) and (4).

[0097] [Mathematical formula 3]

[0098] τ m =(K pm +K ps )(X s -X m )+K is ∫(X s -X m )dt (3)

[0099] [Formula 4]

[0100] τ s =K ps (X m -x s )+K is ∫(X m -X s )dt (4)

[0101] Here, by substituting equations (3) and (4) into equations (1) and (2) and performing Laplace transform, the following equation (5) can be obtained.

[0102] [Formula 5]

[0103]

[0104] Here, G(s) satisfies the following mathematical formula (6).

[0105] [Mathematical formula 6]

[0106]

[0107] Here, if T and a satisfy equations (7) and (8), equation (9) holds.

[0108] [Formula 7]

[0109]

[0110] [Mathematical formula 8]

[0111]

[0112] [Mathematical formula 9]

[0113]

[0114] That is to say, it can be seen from mathematical formula (9) that asymmetric bidirectional control has a phase lead compensation characteristic. Therefore, by making the proportional control gain |Kpm| of the master device higher than the proportional control gain |Kps| of the slave device, the gain of G(s) becomes a in the high-frequency region and becomes 1 in the low-frequency region. In other words, when the external force Fs applied to the slave device changes significantly, such as when the slave device contacts the object, a multiple of the force will be fed back to the master device, and in a stable state, a multiple of the force will be fed back to the master device. Therefore, asymmetric bidirectional control is conducive to achieving high-precision following performance and high-sensitivity force feedback of the slave device through integral control.

[0115] [(3) Modification of Master Control / Slave Control]

[0116] As shown in equations (10) and (11), in equations (3) and (4), the inertial force and the viscous force can be compensated by using acceleration and velocity, respectively.

[0117] [Formula 10]

[0118]

[0119] [Mathematical formula 11]

[0120]

[0121] From equation (10) and equation (11), we can get equation (12).

[0122] [Mathematical formula 12]

[0123] F m (s)=G(s)F s (12)

[0124] As can be seen from equation (12), the dynamic effects in the master device and the slave device can be suppressed by adding compensation as shown in equations (10) and (11).

[0125] In addition, the drive force τs of the slave device is calculated by proportional control and integral control in the slave control unit 31. However, the drive force τs of the slave device may be calculated by a disturbance observer instead of the integral control.

[0126] Furthermore, in the asymmetric bidirectional control, the main control unit 30 calculates the driving force τm of the master device by subtracting the driving force τs of the slave device from τm' output by the transmission element 3D. However, the calculation method of τm is not limited thereto and can be determined appropriately. Specifically, for example, τs' can be calculated by performing a prescribed operation based on the driving force τs of the slave device, and τs' can be subtracted from τm' to calculate τm. In addition, the prescribed operation may be, for example, multiplying τs by or adding a prescribed coefficient. In addition, for example, τm can be calculated by multiplying τm' by τs (or τs') or dividing τs' (or τs') or adding τs' (or τs').

[0127] In the transmission element 3B, τs may be calculated without using integral control and disturbance observer. In the transmission elements 3B and 3D, τs or τm' may be calculated by further performing differential control.

[0128] [(4) Gain adjustment]

[0129] The function of the gain adjustment unit 32 is realized by the operation of the processor of the control unit 3 (see Figure 2 The gain adjustment unit 32 adjusts the gains of the proportional control and the integral control in the asymmetric bidirectional control according to the operation from the user or the like received via the receiving unit 44 .

[0130] That is, the storage device 33 stores the proportional control gain Kpm in the master control unit 30, the proportional control gain Kps in the slave control unit 31, and the integral control gain Kis corresponding to each robot arm 2. Then, for example, when the surgical robot 1 is started, the control unit 3 reads the Kpm, Kps, and Kis corresponding to each robot arm 2 from the storage device 33, and then performs the above-mentioned bidirectional control using the read Kpm, Kps, and Kis.

[0131] When the gain adjustment unit 32 receives an operation signal instructing to adjust the gain from the receiving unit 44, it outputs a control signal to the display unit 43 and displays a gain setting screen 7 (see FIG. 7 ) on the display unit 43. Figure 5 The gain setting screen 7 is provided corresponding to each robot arm 2 and is used to adjust the gain in the bidirectional control of the corresponding robot arm 2. According to the operation signal input from the receiving unit 44, the gain adjustment unit 32 outputs a control signal to the display unit 43 to switch the gain setting screen 7 displayed on the display unit 43 to the gain setting screen 7 corresponding to the different robot arm 2.

[0132] The gain setting screen 7 has display areas 70, 71, and a display area 72, wherein the display areas 70, 71 display the proportional control gain and the integral control gain of the slave device in the control of the position and direction of the grip 50, and the display area 72 displays the proportional control gain of the master device. In addition, the gain setting screen 7 also has display areas 73, 74, and a display area 75, wherein the display areas 73, 74 display the proportional control gain and the integral control gain of the slave device in the control of the opening and closing state of the grip 50, and the display area 75 displays the proportional control gain of the master device. The gain adjustment unit 32 outputs a control signal to the display unit 43, and causes the above-mentioned display areas 70 to 75 to display the current value of the gain in the corresponding proportional control or integral control.

[0133] In addition, on the gain setting screen 7, a cursor 76 is superimposed and displayed on any one of the display areas 70 to 75. The gain adjustment unit 32 selects any one of the display areas 70 to 75 in accordance with the operation signal input from the receiving unit 44, and outputs a control signal to the display unit 43 to superimpose and display the cursor 76 on the selected display area. In addition, the gain adjustment unit 32 receives a change in the gain value displayed in the selected display area in accordance with the operation signal input from the receiving unit 44, and outputs a control signal to the display unit 43 to display the changed gain value in the display area.

[0134] Then, when an operation signal instructing to determine the gain value is input from the receiving unit 44, the gain adjustment unit 32 updates the gain value of the proportional control or integral control corresponding to the display area 70 to 75 to the gain value displayed in the display area. Thereafter, the updated gain value is used in the bidirectional control. In addition, the gain adjustment unit 32 stores each updated gain value in the storage device 33.

[0135] [6. Effect]

[0136] (1) In the bidirectional control of the prior art, symmetrical or force feedback methods of proportional control and integral control are widely used. Moreover, in order to improve the control accuracy, when using forceps as a surgical instrument, even when a large external force (for example, an external force of about 5 to 20N) is applied to the front end of the forceps, it is necessary to suppress the error to a minimum. To this end, it is necessary to increase the proportional control gain in the control of the slave device, but as mentioned above, there is a limit to the increase in the proportional control gain. Therefore, it is necessary to use integral control or a disturbance observer or other integral methods to control the slave device, but the introduction of such a method may cause a delay in force feedback.

[0137] In this regard, in the asymmetric bidirectional control of the present embodiment, τs is calculated in the slave control unit 31 by proportional control and integral control. Therefore, the disturbance in the slave control unit 31 can be well suppressed and the accuracy of τs can be improved. In addition, the main control unit 30 calculates τm based on τs obtained from the slave control unit 31, and controls the reaction force generated in the position operation unit 41 and the grip operation unit 42 as the master device by τm. Therefore, the sensitivity of the force feedback can be improved. That is, in the present embodiment, even if the slave device is controlled by using the integral method, the delay of the force feedback can be suppressed.

[0138] (2) In addition, the proportional control gain |Kpm| of the master device is greater than the proportional control gain |Kps| of the slave device. Therefore, the sensitivity of the force feedback can be improved.

[0139] (3) Furthermore, the gain adjustment unit 32 adjusts each gain in the bidirectional control corresponding to each robot arm according to the operation received via the receiving unit 44. Therefore, the sensitivity of the force feedback can be adjusted and customized so that the surgical instrument can be controlled more appropriately.

[0140] [7. Other embodiments]

[0141] The multiple functions of one component in the above-mentioned embodiment can be realized by multiple components, or the one function of one component can be realized by multiple components. In addition, the multiple functions of multiple components can be realized by one component, or the one function of multiple components can be realized by one component. In addition, a part of the structure of the above-mentioned embodiment can be omitted. In addition, at least a part of the structure of the above-mentioned embodiment can be added to the structure of the above-mentioned other embodiment, or at least a part of the structure of the above-mentioned embodiment can be replaced with the structure of the above-mentioned other embodiment, etc.

[0142] [8. Correspondence of terms]

[0143] The position operation unit 41 and the grip operation unit 42 of the operation device 40 correspond to an example of a master device unit. In addition, the first drive unit 23 to the third drive unit 25 of the robot arm 2 correspond to an example of a slave device unit, and the sensor unit 26 of the robot arm 2 and the sensor units 50A and 52A of the surgical instrument correspond to an example of a slave device detection unit.

[0144] [9. Technical ideas disclosed in this specification]

[0145] [Project 1]

[0146] A surgical robot, characterized by comprising:

[0147] a main device unit configured to receive an operation from a user and apply a reaction force to the user who performs the operation;

[0148] a main control unit, the main control unit being configured to control the main equipment unit and generate the reaction force;

[0149] a slave device unit that operates a surgical instrument;

[0150] A slave control unit configured to control the slave device unit and operate the surgical instrument based on a target state, wherein the target state is a state of the surgical instrument that is operated based on the operation received by the master device unit; and

[0151] a slave device detection unit configured to detect a surgical instrument state, wherein the surgical instrument state is a state of the surgical instrument, and

[0152] The slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on the surgical instrument state and the target state, and to control the slave device unit based on the slave control value.

[0153] The main control unit is configured to calculate a master control value for controlling the reaction force based on the surgical instrument state, the target state, and the slave control value acquired from the slave control unit, and control the main device unit based on the master control value.

[0154] [Project 2]

[0155] The surgical robot according to item 1 is characterized in that:

[0156] The slave control unit is configured to calculate the slave control value by performing integration based on the surgical instrument state and the target state.

[0157] [Item 3]

[0158] The surgical robot according to item 1 or 2 is characterized in that:

[0159] The slave control unit is configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state.

[0160] The main control unit is configured to calculate the main control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state.

[0161] A gain of proportional control in the master control section is greater than a gain of proportional control in the slave control section.

[0162] [Item 4]

[0163] The surgical robot according to any one of items 1 to 3 is characterized in that:

[0164] The main control unit is configured to calculate the main control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state.

[0165] And the surgical robot also has:

[0166] a display unit configured to display a gain of the proportional control; and

[0167] A receiving unit configured to receive an operation for changing a gain of the proportional control.

[0168] [Item 5]

[0169] The surgical robot according to any one of items 1 to 4 is characterized in that:

[0170] The slave control unit is configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state.

[0171] And the surgical robot also has:

[0172] a display unit configured to display a gain of the proportional control; and

[0173] A receiving unit configured to receive an operation for changing a gain of the proportional control.

[0174] [Item 6]

[0175] The surgical robot according to item 5 is characterized in that:

[0176] The slave control unit is configured to calculate the slave control value by further performing integral control, wherein the integral control is performed based on a difference between the surgical instrument state and the target state.

[0177] a display unit configured to also display a gain of the integral control; and

[0178] The receiving unit is configured to further receive an operation for changing a gain of the integral control.

[0179] [Item 7]

[0180] A control unit of a surgical robot, characterized by comprising:

[0181] a main control unit configured to control a main device unit and generate a reaction force, wherein the main device unit is configured to receive an operation from a user and apply the reaction force to the user who performs the operation; and

[0182] A slave control unit, the slave control unit is configured to control the slave device unit and operate the surgical instrument based on a target state, wherein the target state is a state of the surgical instrument that is operated based on the operation accepted by the master device unit, and the slave device unit operates the surgical instrument, and

[0183] The slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on a surgical instrument state and the target state, and to control the slave device unit based on the slave control value, wherein the surgical instrument state is a state of the surgical instrument detected by the slave device detection unit,

[0184] The main control unit is configured to calculate a master control value for controlling the reaction force based on the surgical instrument state, the target state, and the slave control value acquired from the slave control unit, and control the main device unit based on the master control value.

Claims

1. A surgical robot, characterized in that: have: a main device unit configured to receive an operation from a user and apply a reaction force to the user who performs the operation; a main control unit, the main control unit being configured to control the main equipment unit and generate the reaction force; a slave device unit that operates a surgical instrument; A slave control unit configured to control the slave device unit and operate the surgical instrument based on a target state, wherein the target state is a state of the surgical instrument that is operated based on the operation received by the master device unit; and a slave device detection unit configured to detect a surgical instrument state, wherein the surgical instrument state is a state of the surgical instrument, and The slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on the surgical instrument state and the target state, and to control the slave device unit based on the slave control value. The main control unit is configured to calculate a master control value for controlling the reaction force based on the surgical instrument state, the target state, and the slave control value acquired from the slave control unit, and control the main device unit based on the master control value.

2. The surgical robot according to claim 1, characterized in that: The slave control unit is configured to calculate the slave control value by performing integration based on the surgical instrument state and the target state.

3. The surgical robot according to claim 1 or 2, characterized in that: The slave control unit is configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state. The main control unit is configured to calculate the main control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state. A gain of proportional control in the master control section is greater than a gain of proportional control in the slave control section.

4. The surgical robot according to claim 1 or 2, characterized in that: The main control unit is configured to calculate the main control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state. And the surgical robot also has: a display unit configured to display a gain of the proportional control; and A receiving unit configured to receive an operation for changing a gain of the proportional control.

5. The surgical robot according to claim 1 or 2, characterized in that: The slave control unit is configured to calculate the slave control value by proportional control, wherein the proportional control is performed based on a difference between the state of the surgical instrument and the target state. And the surgical robot also has: a display unit configured to display a gain of the proportional control; and A receiving unit configured to receive an operation for changing a gain of the proportional control.

6. The surgical robot according to claim 5, characterized in that: The slave control unit is configured to calculate the slave control value by further performing integral control, wherein the integral control is performed based on a difference between the surgical instrument state and the target state. a display unit configured to also display a gain of the integral control; and The receiving unit is configured to further receive an operation for changing a gain of the integral control.

7. A control unit of a surgical robot, characterized in that: have: a main control unit configured to control a main device unit and generate a reaction force, wherein the main device unit is configured to receive an operation from a user and apply the reaction force to the user who performs the operation; and A slave control unit, the slave control unit is configured to control the slave device unit and operate the surgical instrument based on a target state, wherein the target state is a state of the surgical instrument that is operated based on the operation accepted by the master device unit, and the slave device unit operates the surgical instrument, and The slave control unit is configured to calculate a slave control value for controlling the surgical instrument based on a surgical instrument state and the target state, and to control the slave device unit based on the slave control value, wherein the surgical instrument state is a state of the surgical instrument detected by the slave device detection unit, The main control unit is configured to calculate a master control value for controlling the reaction force based on the surgical instrument state, the target state, and the slave control value acquired from the slave control unit, and control the main device unit based on the master control value.

Images