JP7723718B2 - Input device for surgical manipulator - Google Patents

Description

The present invention relates to an input device for a surgical manipulator.

A known example of an input device for a surgical manipulator is the master device described in Patent Document 1. In this master device, a wrist is rotatably attached to the tip of a three-axis arm. The wrist is formed on a three-axis (joint) linkage that forms a gimbal with three degrees of freedom. A handle operated by the operator is formed on the tip of this three-axis linkage. A processor then rotates the wrist relative to the tip of the arm based on the rotational position of each axis (joint) of the wrist, thereby controlling each axis of the wrist to an angle close to a right angle. This minimizes the inertia and friction of the master's linkage, regardless of the direction in which the handle rotates (see paragraph [0029] of Patent Document 1).

US Patent Publication US2002/0120363A1

In order to perform surgery using a surgical robot (surgical manipulator), the operator must operate the handle with delicate control of force. Therefore, the master device (the input device for the surgical manipulator) must be able to adjust the force (hereinafter sometimes referred to as the operating force) required for the operator to operate the handle (operating unit).

However, the description in Patent Document 1 does not make clear whether the inertial force of the master link connecting body, which is part of the operating force, is compensated for in the first place. Naturally, therefore, Patent Document 1 makes no mention (disclosure) of adjusting the operating force, including the inertial force. This has led to the issue of being unable to adjust the operating force.

The present invention was made to solve the above-mentioned problems, and aims to provide an input device for a surgical manipulator that can adjust the operating force.

In order to achieve the above-mentioned object, an input device for a surgical manipulator according to one aspect of the present invention comprises: a master arm having a joint and equipped with an operation unit at its tip that is operated by an operator; a motor that drives the joint of the master arm via a power transmission element; a controller that calculates a force compensation amount for the inertial force of the master arm based on the acceleration of the power transmission element that moves in response to operation of the operation unit by the operator, and controls operation of the motor to perform force compensation of the force compensation amount to cancel out the inertial force; a memory that stores a plurality of ranked force compensation amounts ranked in order of the magnitude of the compensation amount; and an input device for specifying one of the plurality of ranked force compensation amounts , wherein the controller is configured to adjust the force compensation amount for the inertial force to the ranked force compensation amount specified by the input device .

Here, "force compensation amount" refers to the magnitude of the force that cancels out part or all of the inertial force of the master arm. Furthermore, when an operator operates the master arm, a resistance force from the master arm is applied to the operator. This resistance force includes an inertial force proportional to the inertia and acceleration of the master arm. Hereinafter, the compensation amount for the resistance force will be referred to as the "resistance force compensation amount," and the compensation amount for the inertial force will be referred to as the "inertia force compensation amount." Therefore, if gravity acting on the master arm is ignored (or if gravity compensation is applied to the operating force), the difference between the resistance force and the resistance force compensation amount will be the operating force, which is the force required by the operator to operate the master arm.

According to the above configuration, the controller calculates a force compensation amount for the inertial force of the master arm based on the acceleration of the power transmission element that moves when the operator operates the operating unit, and controls the operation of the motor to perform force compensation by this force compensation amount. Therefore, for example, by selecting a force compensation amount for the inertial force of the master arm as the force compensation amount, the operating force can be finely set. Furthermore, since the controller adjusts the force compensation amount for the inertial force, the operating force can be adjusted. Furthermore, when a ranked force compensation amount, which is a compensation amount that compensates for force so as to obtain an operating force preferred by the operator, is input into the input device, the controller adjusts the force compensation amount to the specified ranked force compensation amount, so that the operating force can be set to an operating force preferred by the operator.

The system may include a memory that stores designated force compensation amounts corresponding to each of the multiple operators, and an input device for identifying the operator corresponding to the designated force compensation amount, and the controller may be configured to adjust the force compensation amount for the inertial force to the designated force compensation amount corresponding to the operator identified by the input device.

With this configuration, the specified force compensation amount that compensates for the operating force desired by each operator is stored in a memory device in association with that operator, allowing the operating force to be set to the operating force desired by the operator.

The controller may include an acceleration acquisition unit that acquires an acceleration of the power transmission element , an inertia force compensation amount calculation unit that calculates a force compensation amount for the inertial force based on the acceleration of the power transmission element acquired by the acceleration acquisition unit and the inertia of the master arm, and a power converter that supplies power to the motor for force compensation of the force compensation amount for the inertial force.

This configuration allows for precise setting of the operating force, and also makes it possible to realize an input device for a surgical manipulator that allows for the operating force to be adjusted.

The master arm may have a plurality of the joints, the input device may include a plurality of the power transmission elements and a plurality of the motors, each of which drives a respective one of the joints via a respective one of the power transmission elements, and the controller may be configured to calculate, for each of the joints, a force compensation amount for the inertial force of the portion of the master arm driven by each joint based on the acceleration of each of the power transmission elements that moves in response to the operator's operation of the operating unit, and to control the operation of each of the motors to perform force compensation by the force compensation amount.

This configuration allows for precise setting and adjustment of the operating force in the input device of a surgical manipulator equipped with a master arm with multiple joints.

The controller may be configured to adjust, for each joint, the amount of force compensation for the inertial force of the part of the master arm driven by each joint.

This configuration allows the force compensation amount to be adjusted for each joint in the input device of a surgical manipulator equipped with a master arm with multiple joints, allowing for more precise adjustment of the operating force.

The controller may further be configured to control the operation of the motor so that the attitude of the master arm does not change due to gravity.

With this configuration, when the operator stops the master arm, the master arm remains in the stopped position.

The controller may further be configured to calculate the position of the operating unit based on the position of the power transmission element that moves in response to the operator's operation of the operating unit, and to output this calculated position of the operating unit to the surgical manipulator.

According to this configuration, the surgical manipulator can be operated according to the position of the operating part.
In order to achieve the above-mentioned object, an input device for a surgical manipulator according to one aspect of the present invention comprises: a master arm having a joint and equipped with an operation unit at its tip that is operated by an operator; a motor that drives the joint of the master arm via a power transmission element; a controller that calculates a force compensation amount for a viscous force of the master arm based on the speed of the power transmission element that moves in response to operation of the operation unit by the operator, and controls operation of the motor to perform force compensation of the force compensation amount to cancel out the viscous force; a memory that stores a plurality of ranked force compensation amounts ranked in order of the magnitude of the compensation amount; and an input device for specifying one of the plurality of ranked force compensation amounts , wherein the controller is configured to adjust the force compensation amount for the viscous force to the ranked force compensation amount specified by the input device .
Here, "force compensation amount" refers to the magnitude of a force that cancels out part or all of the viscous force of the master arm. Furthermore, when an operator operates the master arm, a resistance force from the master arm is applied to the operator. This resistance force includes a viscous force proportional to the viscosity and speed of the master arm. Hereinafter, the compensation amount for the viscous force will be referred to as the "viscous force compensation amount." Therefore, if gravity acting on the master arm is ignored (or if gravity compensation is applied to the operation force), the difference between the resistance force and the resistance force compensation amount is the operation force, which is the force the operator needs to operate the master arm.
According to the above configuration, the controller calculates a force compensation amount for the viscous force of the master arm based on the speed of the power transmission element that moves when the operator operates the operating unit, and controls the operation of the motor to perform force compensation by this force compensation amount. Therefore, by selecting a force compensation amount for the viscous force of the master arm as the force compensation amount, the operating force can be finely set. Furthermore, since the controller adjusts the force compensation amount for the viscous force, the operating force can be adjusted . Furthermore, when a ranked force compensation amount, which is a compensation amount that compensates for force so as to obtain an operating force preferred by the operator, is input into the input device, the controller adjusts the force compensation amount to the specified ranked force compensation amount, so that the operating force can be set to an operating force preferred by the operator.
The controller may be configured to include a memory that stores a specified force compensation amount corresponding to each of a plurality of operators, and an input device that identifies the operator corresponding to the specified force compensation amount, and the controller may be configured to adjust the force compensation amount for the viscous force to the specified force compensation amount corresponding to the operator identified by the input device.
According to this configuration, the specified force compensation amount for compensating for the force so that the operating force becomes the operating force desired by each operator is stored in a memory device in correspondence with the operator, so that the operating force can be set to the operating force desired by the operator.
The controller may include a speed acquisition unit that acquires the speed of the power transmission element, a viscous force compensation amount calculation unit that calculates a force compensation amount for the viscous force based on the speed of the power transmission element acquired by the speed acquisition unit and the viscosity of the master arm, and a power converter that supplies power to the motor for force compensation of the force compensation amount for the viscous force.
According to this configuration, it is possible to realize an input device for a surgical manipulator that allows the operating force to be finely set and, moreover, allows the operating force to be adjusted.
The master arm may have a plurality of the joints, and the input device may include a plurality of the power transmission elements and a plurality of the motors, each of which drives a respective one of the joints via a respective one of the power transmission elements, and the controller may be configured to calculate, for each of the joints, a force compensation amount for the viscous force of the part of the master arm driven by each joint based on the speed of each of the power transmission elements that moves in response to operation of the operating unit by the operator, and to control the operation of each of the motors to perform force compensation of the force compensation amount.
According to this configuration, in the input device of the surgical manipulator equipped with a master arm having a plurality of joints, the operating force can be set in detail and, moreover, the operating force can be adjusted.
The controller may be configured to adjust, for each of the joints, a force compensation amount for a viscous force of a portion of the master arm driven by the joint.
According to this configuration, in an input device for a surgical manipulator equipped with a master arm having a plurality of joints, the amount of force compensation can be adjusted for each joint, allowing for more detailed adjustment of the operating force.
The controller may be further configured to control operation of the motor so that the attitude of the master arm does not change due to gravity.
According to this configuration, when the operator stops the master arm, the master arm stays at the stop position.
The controller may be further configured to calculate the position of the operating unit based on the position of the power transmission element that moves in response to the operator's operation of the operating unit, and to output the calculated position of the operating unit to a surgical manipulator.
According to this configuration, the surgical manipulator can be operated according to the position of the operating part.

The present invention has the advantage of providing an input device for a surgical manipulator that allows for precise setting of operating force and, moreover, allows for adjustment of operating force.

FIG. 1 is a schematic diagram showing an overview of an example of a robot-assisted surgery system including an input device for a surgical manipulator according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing an outline of the appearance of an example of a hand control included in the robot-assisted surgery system of FIG. FIG. 3 is a side view schematically illustrating the input device shown in FIG. 2. As shown in FIG. 4 is a cross-sectional view showing a longitudinal section of a shoulder portion of the arm portion of the master arm of FIG. 3. FIG. 5 is a cross-sectional view showing a longitudinal section of the upper arm portion of the arm portion of the master arm of FIG. 3. FIG. FIG. 6 is a perspective view showing the appearance of the wrist portion of the master arm of FIG. 7 is a cross-sectional view showing a vertical section of the fourth link and the fifth link of the wrist portion of FIG. 6. FIG. 8 is a cross-sectional view showing a vertical section of the sixth link and the operating unit of the wrist portion of FIG. 6. FIG. FIG. 9 is a functional block diagram showing an example of the configuration of a control system for an input device and a surgical manipulator. FIG. 10 is a functional block diagram showing an example of the configuration of the input device controller shown in FIG. FIG. 11 is a block diagram showing the configuration of the resistance force compensation amount calculation unit shown in FIG. FIG. 12 is a graph showing an example of the ranking force compensation amount. FIG. 13 is a graph showing an example of the designated force compensation amount for each operator.

Embodiments of the present invention will be described below with reference to the drawings. Note that identical or corresponding elements will be designated by the same reference numerals throughout the drawings, and redundant explanations will be omitted. Furthermore, since the following drawings are for the purpose of explaining the present invention, elements unrelated to the present invention may be omitted from these drawings, dimensions may be inaccurate due to exaggeration, and corresponding elements may not match between multiple drawings.

Note that the present invention is not limited to the following embodiments.

(Embodiment)
[composition]
{Hardware configuration}
Fig. 1 is a schematic diagram showing an overview of an example of a robot-assisted surgery system including an input device for a surgical manipulator according to a first embodiment of the present invention. Fig. 2 is a schematic diagram showing an overview of the appearance of an example of a hand control provided in the robot-assisted surgery system of Fig. 1. In the following description, the up and down directions in Fig. 1 and Fig. 2 are described as up and down directions in absolute space.

Referring to Figures 1 and 2, the robotically-assisted surgical (RAS) system 200 includes a positioner 201, a surgical manipulator 202, and a hand control 100.

<Robotic-assisted surgery system 200>
Referring to FIG. 1 , for example, an operating room has an operating table 203 and a patient 204 lying on the operating table 203. A positioner 201 is disposed near the operating table 203. The positioner 201 is configured, for example, by an articulated robot. A surgical manipulator 202 configured by the articulated robot is attached to a base 201a at the tip of the positioner 201. The surgical manipulator 202 has, for example, a base, an arm 401, and an end effector. The base is fixed to the base 201a, and the base is connected to a link 404, the links 404 to each other, and the link 404 to the end effector by multiple joints. A plurality of (here, for example, four) arm units 401 are connected to the base. A surgical tool 402 is attached to the tip of each of the multiple arm units 401 as an end effector unit.

The positioner 201 transports the surgical manipulator 202 to a position suitable for the surgical manipulator 202 to perform surgery on the patient 204.

<Hand Control 100>
Figure 2 shows an overview of the hand control 100. Note that Figure 2 is a diagram that clearly shows the concept of the hand control 100, and therefore, the detailed structure of the input device 2 in particular is shown in Figure 2 differently from the specific structure shown in Figures 3 to 8, which will be described later.

Referring to Figure 2, the hand control 100 is a device that allows the operator (the surgeon) to control the operation of the surgical manipulator 202 to perform surgery. The hand control 100 is electrically connected to the positioner 201 and the surgical manipulator 202 via wire or wirelessly. The hand control 100 is placed, for example, near the operating table or in a separate room.

The hand control 100 here comprises a main body 1, an input device 2, a plurality of pedals 4, a display unit 5, and a viewer (not shown).

The main body 1 is formed in a roughly L-shape when viewed from the side, and a right input device 2A and a left input device 2B (input devices for the surgical manipulator) are provided on the right and left sides of the main body 1, respectively. The right input device 2A and the left input device 2B are operated by the operator with their right and left hands, respectively. The right input device 2A and the left input device 2B each function as a master input device for each arm section 401 of the surgical manipulator 202, which serves as a slave robot.

A U-shaped support member 3 is provided on the top of the main body 1 so as to protrude forward. A display unit 5 is provided in the center of the front end of the support member 3. The display unit 5 is configured, for example, as a touch panel, and functions as a screen on which the operator displays or inputs information for making various settings on the hand control 100. A viewer (not shown) is provided on the top of the hand control 100, but since the configuration and function of the viewer are well known, it is not shown in Figure 2 to make the input device 2 easier to see. The viewer displays images captured by an endoscope (surgical tool 402) attached as an end effector to the tip of the arm 401 of the surgical manipulator 202.

Multiple (four in this example) pedals 4 are provided at the bottom of the main body 1 so as to protrude forward. The pedals 4 are used to switch the connections between the right input device 2A and the left input device 2B and each arm of the surgical manipulator 202, and to zoom in on the image displayed on the display unit 5, etc.

For example, the operator sits in a chair placed in front of the hand control 100 and performs surgery by operating the right input device 2A or left input device 2B with the right or left hand while viewing an image of the inside of the patient's 204 body displayed on the viewer.

<Input device 2 of surgical manipulator 202>
FIG. 3 is a side view showing a schematic overview of the input device 2 shown in FIG. 2. FIG. 3 shows a simplified configuration of the input device 2. For specific structural examples of the input device 2, please refer to FIGS. 4 to 8. FIG. 3 shows the right input device 2A. The left input device 2B is simply the right-left structure of the right input device 2A reversed. Therefore, a description of the left input device 2B will be omitted. For convenience, the up-down direction and left-right direction in FIG. 3 will hereinafter be taken to be the up-down direction and front-rear direction of the right input device 2A, respectively. In an initial state, the right input device 2A takes the reference posture shown in FIG. 3.

Referring to Figure 3, the right input device 2A takes a generally L-shaped reference position in a side view. Hereinafter, the reference position of the right input device 2A may be simply referred to as the "reference position." The right input device 2A includes a master arm 10. The master arm 10 includes an arm portion 11 and a wrist portion 12.

{Arm portion 11}
The arm unit 11 includes, for example, a base 21, a first link 22, a second link 23, and a third link 24. The base 21 is fixed to the main body 1 of the hand control 100. One end (here, the upper end) of the first link 22 is connected to one end (here, the lower end) of the base 21 in the vertical direction via a first joint JT1 so as to be rotatable about a first rotation axis A1 extending in the vertical direction. One end (here, the upper end) of the second link 23 is connected to the other end (here, the lower end) of the first link 22 via a second joint JT2 so as to be rotatable about a second rotation axis A2 that is perpendicular to the first rotation axis A1 and extends in the left-right direction. One end of a third link 24 (the rear end in the reference posture) is rotatably connected to the other end (here, the lower end) of the second link 23 via a third joint JT3 about a third rotation axis A3 extending parallel to the second rotation axis A2. One end of a swinging member 25 is rotatably provided to the other end of the first link 22 about the second rotation axis A2. One end (here, the upper end) of an auxiliary link 26 is rotatably connected to the other end of the swinging member 25 about a ninth rotation axis A9. The ninth rotation axis A9 is parallel to the second rotation axis A2 and extends a predetermined distance away from the second rotation axis A2. The other end (here, the lower end) of the auxiliary link 26 is rotatably connected to one end of the third link about a tenth rotation axis A10. The tenth rotation axis A10 is parallel to the third rotation axis A3 and extends the predetermined distance from the third rotation axis A3 in a direction toward one end of the third link 24. In other words, the auxiliary link 26 and the second link 23 form a parallel link.

The wrist 12 is connected to the other end of the third link 24 (the front end in the reference posture) via a fourth joint JT4 so as to be rotatable about a fourth rotation axis A4. The fourth rotation axis A4 extends perpendicular to a plane containing the third rotation axis A3 and the tenth rotation axis A10.

Figure 4 is a cross-sectional view showing a longitudinal section of the shoulder portion of the arm portion 11 of the input device of Figure 3. Referring to Figure 4, the shoulder portion is composed of a base body 21, which is formed in a frame shape. A first motor M1 is mounted on the base body 21 facing downward. Specifically, the first motor M1 is mounted so that its main shaft S1 is coaxial with the first rotation axis A1. The first motor M1 is provided with a first rotation angle detector E1 that detects the rotation angle of the first motor M1. The first rotation angle detector E1 may be any device capable of detecting the rotation angle, and may be composed of, for example, an encoder or a tachometer. In this example, the first rotation angle detector E1 is composed of an encoder directly connected to the main shaft S1 of the first motor M1. The main shaft S1 is connected coaxially to the first rotation axis R1 (see Figure 5) of the first link 22 using a cylindrical connecting member 62.

Figure 5 is a cross-sectional view showing a longitudinal section of the upper arm of the arm unit 11 of the right input device 2A of Figure 3. Referring to Figure 5, the upper arm of the arm unit 11 includes a first link 22, a second link 23, and an auxiliary link 26. The first link 22 is formed in a frame shape. A first rotation axis R1 is provided at one end (here, the upper end) of the first link 22. As described above, the first rotation axis R1 is coaxially connected to the main shaft S1 of the first motor M1. This first rotation axis R1 and the first motor M1 form a first joint JT1, which allows the first link 22 to freely rotate about the first rotation axis A1 relative to the base 21. The rotation angle of the first motor M1 caused by the rotation of the first link 22 can be detected by the first rotation angle detector E1, and the first rotation axis R1 can be rotationally driven by the first motor M1.

The second link is formed in the shape of a hollow rod. A second rotation axis R2 is provided at one end (upper end) of the second link 23. This second rotation axis R2 is attached to the other end (lower end) of the first link 22 via a bearing 51 so as to be rotatable around the second rotation axis A2. The second rotation axis R2 and bearing 51 form a second joint JT2, which allows the second link 23 to rotate freely around the second rotation axis A2 relative to the first link 22.

A driven pulley 33 is provided on the second rotation shaft R2. Meanwhile, a second motor M2 is provided on the first link 22 so that the central axis of the main shaft S2 is parallel to the second rotation axis A2. The second motor M2 is provided with a second rotation angle detector E2 that detects the rotation angle of the second motor M2. The second rotation angle detector E2 may be any device that can detect the rotation angle, and may be configured, for example, by an encoder, a tachometer, or the like. In this example, the second rotation angle detector E2 is configured by an encoder directly connected to the main shaft S2 of the second motor M2.

A drive pulley 32 is provided on the main shaft S2 of the second motor M2. A belt 34 is wound around this drive pulley 32 and driven pulley 33. This allows the second rotation angle detector E2 to detect the rotation angle of the second motor M2 caused by the rotation of the second link 23, and also allows the second motor M2 to rotate the second rotation shaft R2.

Furthermore, a tension coil spring (auxiliary spring) SP1 is provided between an appropriate position (here, the center) of the second link 23 and the first link 22. This tension coil spring SP1 is provided so that its central axis is perpendicular to the second rotation axis A2 and the third rotation axis A3. Furthermore, this tension coil spring SP1 is designed to apply a predetermined torque to the second rotation axis R2 in the rotation direction when the second link 23 rotates from the reference posture. This predetermined torque is set to cancel out a portion of the torque (hereinafter sometimes referred to as gravitational torque) generated on the second rotation axis R2 by the weight of the portion of the arm portion 11 beyond the second link 23 and the wrist portion 12. As a result, a portion of the gravitational torque generated on the second rotation axis R2 is canceled out by the tension coil spring SP1.

The third link 24 is formed as a rod-shaped box, and houses the main elements inside. A third rotation axis R3 is provided at one end (rear end) of the third link 24. This third rotation axis R3 is attached to the other end of the second link 23 via a bearing 52 so as to be rotatable around the third rotation axis A3. The third rotation axis R3 and bearing 52 form a third joint JT3, which allows the third link 24 to rotate freely around the third rotation axis A3 relative to the second link 23.

On the other hand, the swinging member 25 is formed in the shape of a long, thin plate, and an eleventh rotation axis R11 is provided at one end of this swinging member 25. This eleventh rotation axis R11 is attached to the other end of the first link 22 via a bearing 53 so as to be rotatable around the second rotation axis A2.

A ninth rotation axis R9 is provided at the other end of the swinging member 25. This ninth rotation axis R9 is connected to one end of the auxiliary link 26 via a bearing (not shown) so as to be rotatable around the ninth rotation axis A9.

A tenth rotation axis R10 is provided between one end of the third link 24 and the third joint JT3. This tenth rotation axis is connected to the other end of the auxiliary link 26 via a bearing (not shown) so as to be rotatable around the tenth rotation axis A10. As described above, the auxiliary link 26 and the second link 23 form a parallel link.

Furthermore, a driven pulley 44 is provided on the eleventh rotation axis R11. Meanwhile, a third motor M3 is provided at an appropriate position on the first link 22 so that the central axis of the main shaft S3 is parallel to the eleventh rotation axis A11. The third motor M3 is provided with a third rotation angle detector E3 that detects the rotation angle of the third motor M3. The third rotation angle detector E3 may be any device that can detect the rotation angle, and may be composed of, for example, an encoder or tachometer. In this case, the third rotation angle detector E3 is composed of an encoder directly connected to the main shaft S3 of the third motor M3.

A drive pulley 42 is provided on the main shaft S3 of the third motor M3. A belt 34 is wound around this drive pulley 42 and the driven pulley 33.

According to the above-described configuration related to the auxiliary link 26, when the third link 24 rotates, the auxiliary link 26 moves parallel to the second link 23, thereby swinging the swinging member 25, and the driven pulley 44, the drive pulley 42, and the third motor M3 rotate in sequence in response to the swinging of the swinging member 25. Therefore, this series of operations makes it possible to detect the rotation angle of the third motor M3 caused by the rotation of the third link 24 using the third rotation angle detector E3. Furthermore, by performing the reverse of this series of operations, it is possible to rotate the third rotation shaft R3 using the third motor M3.

In addition, a compression coil spring (not shown) is provided between the swinging member 25 and the first link 22. This compression coil spring is designed to constantly generate a torque that rotates the swinging member downward. This torque is set to cancel out a portion of the gravitational torque generated on the ninth rotation axis R9 due to the weight of the third link 24 of the arm portion 11 and the wrist portion 12. As a result, a portion of the gravitational torque generated on the ninth rotation axis R9 is canceled out by this coil spring.

{List section 12}
FIG. 6 is a perspective view showing the external appearance of the wrist unit 12 of the input device of FIG. 3 . FIG. 6 shows the wrist unit 12 in a reference posture. Referring to FIG. 6 , the wrist unit 12 includes, for example, a fourth link 71, a fifth link 72, a sixth link 73, and an operating unit 74 as a seventh link. The fourth link 71, the fifth link 72, the sixth link 73, and the operating unit 74 form a three-axis (three degrees of freedom) gimbal. Specifically, the fifth link 72 is rotatable relative to the fourth link 71 about a fifth rotation axis A5, the sixth link 73 is rotatable relative to the fifth link 72 about a sixth rotation axis A6 perpendicular to the fifth rotation axis A5, and the operating unit 74 is rotatable relative to the sixth link 73 about a seventh rotation axis A7 perpendicular to the fifth rotation axis A5 and the sixth rotation axis A6. Therefore, the operator can rotate the operating unit 74 around the intersection of these three rotation axes A5 to A7 and point it in any direction.

Referring to Figures 3 and 6, the fourth link 71 is formed in an L-shape, and one end of this fourth link 71 (the front end in the reference position) is connected to the other end (the front end in the reference position) of the third link 24 (see Figure 3) via the fourth joint JT4 so as to be rotatable about the fourth rotation axis. The fourth rotation axis A4 is perpendicular to a plane containing the third rotation axis A3 and the tenth rotation axis A10.

Referring to FIG. 6 , one end of the fifth link 72 (the rear end in the reference posture) is rotatably connected to the other end of the fourth link 71 (the rear end in the reference posture) via a fifth joint JT5 around a fifth rotation axis A5 perpendicular to the fourth rotation axis A4. The fifth link 72 is formed in an L-shape that is slightly smaller than the fourth link 71. One end of the sixth link 73 (the right end in the reference posture) is rotatably connected to the other end of the fifth link 72 (the front end in the reference posture) around the sixth rotation axis A6 via a sixth joint JT6. The sixth link 73 is formed in an L-shape that is slightly smaller than the fifth link 72. One end of the operating unit 74 (the left end in the reference posture) is rotatably connected to the other end of the sixth link 73 (the left end in the reference posture) around the seventh rotation axis A7 via a seventh joint JT7. The operating unit 74 comprises a rod-shaped main body and a pair of cylindrical finger insertion sections 74a attached to the main body. The pair of finger insertion sections 74a are configured so that the operator can insert their thumb and index finger into them and operate the pair of finger insertion sections 74a with the thumb and index finger as if pinching and releasing an object.

Next, an example of the detailed structure of the list section 12 will be described.

Figure 7 is a cross-sectional view showing a vertical section of the fourth link 71 and the fifth link 72 of the wrist section 12 in Figure 6. Figure 8 is a cross-sectional view showing a vertical section of the sixth link 73 and the operating unit 74 of the wrist section 12 in Figure 6. Figure 7 shows a cross-section of the wrist section 12 taken along a plane including the fifth rotation axis A5 and the sixth rotation axis A6, and Figure 8 shows a cross-section of the wrist section 12 taken along a plane including the sixth rotation axis A6 and the seventh rotation axis A7.

Referring to Figure 7, the fourth link 71 is formed in an L-shaped box, with the main elements housed inside the box. A fourth rotation axis R4 is provided at one end (front end) of the fourth link 71. This fourth rotation axis R4 is attached to the other end (front end) of the third link 24 via a bearing 81 so as to be rotatable about a fourth rotation axis A4. The fourth rotation axis R4 and bearing 81 form a fourth joint JT4, which allows the fourth link 71 to rotate freely about the fourth rotation axis A4 relative to the third link 24.

Furthermore, a fourth motor M4 is provided inside the third link 24 so that the center axis of the main shaft S4 is perpendicular to the fourth rotation axis A4. The fourth motor M4 is provided with a fourth rotation angle detector E4 that detects the rotation angle of the fourth motor M4. The fourth rotation angle detector E4 may be any device capable of detecting the rotation angle, such as an encoder or tachometer. In this example, the fourth rotation angle detector E4 is an encoder directly connected to the main shaft S4 of the fourth motor M4. The main shaft S4 of the fourth motor M4 is connected to the fourth rotation axis R4 via a bevel gear mechanism G1. This allows the fourth rotation angle detector E4 to detect the rotation angle of the fourth motor M4 caused by the rotation of the fourth link 71, and also allows the fourth rotation axis R4 to be rotated by the fourth motor M4.

The fifth link 72 is formed into an L-shaped box, with the main elements housed inside the box. A fifth rotation axis R5 is provided at one end (rear end) of the fifth link 72. This fifth rotation axis R5 is attached to the other end (rear end) of the fourth link 71 via a bearing 82 so as to be rotatable around the fifth rotation axis A5. This fifth rotation axis R5 and bearing 82 form a fifth joint JT5, which allows the fifth link 72 to rotate freely around the fifth rotation axis A5 relative to the fourth link 71.

Furthermore, a fifth motor M5 is provided inside the fourth link 71 so that the center axis of the main shaft S5 is perpendicular to the fifth rotation axis A5. The fifth motor M5 is provided with a fifth rotation angle detector E5 that detects the rotation angle of the fifth motor M5. The fifth rotation angle detector E5 may be any device capable of detecting the rotation angle, such as an encoder or tachometer. In this example, the fifth rotation angle detector E5 is an encoder directly connected to the main shaft S5 of the fifth motor M5. The main shaft S5 of the fifth motor M5 is connected to the fifth rotation axis R5 via a bevel gear mechanism G2. This allows the fifth rotation angle detector E5 to detect the rotation angle of the fifth motor M5 caused by the rotation of the fifth link 72, and also allows the fifth rotation axis R5 to be rotated by the fifth motor M5.

Furthermore, a compression coil spring SP2 (auxiliary spring) is provided between an appropriate position of the fourth link 71 (here, the lower end of the rear end in the reference posture) and the fifth rotation axis R5. This compression coil spring SP2 is provided so that its central axis is parallel to the fourth rotation axis A4 and perpendicular to the fifth rotation axis A5. Furthermore, this compression coil spring SP2 is designed to apply a predetermined torque to the fifth link 72 in the direction of rotation when the fifth link 72 rotates from the reference posture. This predetermined torque is set to cancel out a portion of the gravitational torque generated on the fifth rotation axis R5 due to the weight of the portion of the wrist section 12 beyond the fifth link. As a result, a portion of the gravitational torque generated on the fifth rotation axis R5 is canceled out by the compression coil spring SP2.

7 and 8 , the sixth link 73 is formed in an L-shaped box, with the main elements housed inside the box. A sixth rotation shaft R6 is provided at one end (right end) of the sixth link 73. This sixth rotation shaft R6 is attached to the other end (front end) of the fifth link 72 via a bearing 83 so as to be rotatable about a sixth rotation axis A6. The sixth rotation shaft R6 and the bearing 83 constitute a sixth joint JT6, which allows the sixth link 73 to rotate freely about the sixth rotation axis A6 relative to the fifth link 72.

Furthermore, a sixth motor M6 is provided inside the fifth link 72 so that the center axis of the main shaft S6 is perpendicular to the sixth rotation axis A6. The sixth motor M6 is provided with a sixth rotation angle detector E6 that detects the rotation angle of the sixth motor M6. The sixth rotation angle detector E6 may be any device capable of detecting the rotation angle, such as an encoder or tachometer. In this example, the sixth rotation angle detector E6 is an encoder directly connected to the main shaft S6 of the sixth motor M6. The main shaft S6 of the sixth motor M6 is connected to the sixth rotation axis R6 via a bevel gear mechanism G3. This allows the sixth rotation angle detector E6 to detect the rotation angle of the sixth motor M6 caused by the rotation of the sixth link 73, and also allows the sixth rotation axis R6 to be rotated by the sixth motor M6.

Referring to Figure 8, a seventh rotation axis R7 is provided at one end (left end) of the operating unit 74. This seventh rotation axis R7 is attached to the other end (left end) of the sixth link 73 via a bearing 84 so as to be rotatable around the seventh rotation axis A7. This seventh rotation axis R7 and bearing 84 form a seventh joint JT7, which allows the operating unit 74 to rotate freely around the seventh rotation axis A7 relative to the sixth link 73.

Furthermore, a seventh motor M7 is provided inside the sixth link 73 so that the center axis of the main shaft S7 is perpendicular to the seventh rotation axis A7. The seventh motor M7 is provided with a seventh rotation angle detector E7 that detects the rotation angle of the seventh motor M7. The seventh rotation angle detector E7 may be any device capable of detecting the rotation angle, such as an encoder or tachometer. In this example, the seventh rotation angle detector E7 is an encoder directly connected to the main shaft S7 of the seventh motor M7. The main shaft S7 of the seventh motor M7 is connected to the seventh rotation axis R7 via a bevel gear mechanism G4. This allows the seventh rotation angle detector E7 to detect the rotation angle of the seventh motor M7 caused by the rotation of the operating unit 74, and also allows the seventh rotation axis R7 to be rotated by the seventh motor M7.

<Power transmission path>
3 and 5, the power transmission path from the first motor M1 to the first joint JT1 is made up of the main shaft S1 and first rotation shaft R1 of the first motor M1. The power transmission path from the second motor M2 to the second joint JT2 is made up of the main shaft S2, drive pulley 32, belt 34, driven pulley 33, and second rotation shaft R2 of the second motor M2. The power transmission path from the third motor M3 to the third joint JT3 is made up of the main shaft S3, drive pulley 42, belt 45, driven pulley 44, eleventh rotation shaft R11, swing member 25, ninth rotation shaft R9, auxiliary link 26, tenth rotation shaft R10, third link 24, and third rotation shaft R3 of the third motor M3.

Referring to Figure 7, the power transmission path from the fourth motor M4 to the fourth joint JT4 is made up of the main shaft S4 of the fourth motor M4, the bevel gear mechanism G1, and the fourth rotation shaft R4. The power transmission path from the fifth motor M5 to the fifth joint JT5 is made up of the main shaft S5 of the fifth motor M5, the bevel gear mechanism G2, and the fifth rotation shaft R5. The power transmission path from the sixth motor M6 to the sixth joint JT6 is made up of the main shaft S6 of the sixth motor M6, the bevel gear mechanism G3, and the sixth rotation shaft R6. Referring to Figure 8, the power transmission path from the seventh motor M7 to the seventh joint JT7 is made up of the main shaft S7 of the seventh motor M7, the bevel gear mechanism G4, and the seventh rotation shaft R7.

<Power transmission elements that form the basis for calculating the resistance force compensation amount>
Here, the power transmission elements that form the basis for calculating the resistance force compensation amount (described later) are the main shafts S1 to S7 of the first to seventh motors M1 to M7. The rotation angles of these main shafts S1 to S7 are detected by first to seventh rotation angle detectors E1 to E7, which are rotation angle sensors, respectively, and the resistance force compensation amount (described later) is calculated based on these rotation angles AG. Note that the power transmission elements that form the basis for calculating the resistance force compensation amount may be other power transmission elements. For example, they may be the first to seventh rotation shafts R1 to R7 of the first to seventh joints JT1 to JT7 or the gears of the bevel gear mechanisms G1 to G4. In this case, encoders may be provided to these power transmission elements to detect their rotation angles.

{Control system configuration}
FIG. 9 is a functional block diagram showing an example of the configuration of a control system for the right input device 2A and the surgical manipulator 202.

Referring to FIG. 9, the right input device 2A is equipped with an input device controller C1. The input device controller C1 is provided, for example, in common with the right input device 2A and the left input device 2B. Because the control by the input device controller C1 is similar for both, only the control relating to the right input device 2A will be described here, and a description of the control relating to the left input device 2B will be omitted. Note that the right input device 2A and the left input device 2B may each be provided with an input device controller C1. The detailed configuration of the input device controller C1 will be described later. The input device controller C1 is provided, for example, in an appropriate location on the hand control 100.

In the right input device 2A, the rotation angles AG of the first to seventh motors M1 to M7, which correspond to the first to seventh joints JT1 to JT7, are detected by the first to seventh rotation angle detectors E1 to E7, respectively, and the detected rotation angles AG of the first to seventh motors M1 to M7 are output to the input device controller C1. The input device controller C1 generates a position (position command signal) P of the operating unit 74 based on the input rotation angles AG of the first to seventh motors M1 to M7, and outputs this position P of the operating unit 74 to the manipulator controller C2. The input device controller C1 also outputs a drive current CR to the first to seventh motors M1 to M7, respectively, based on the input rotation angles AG of the first to seventh motors M1 to M7.

In the surgical manipulator 202, one or more rotation angle detectors E202 detect the rotation angles of one or more motors M202 corresponding to one or more joints connecting the link 404 of the arm unit 401 and the surgical tool 402, and output the detected rotation angles of the one or more motors M202 to the manipulator controller C2. Based on the position (position command signal) P of the operation unit 74 input from the input device controller C1, the manipulator controller C2 outputs a drive current to the one or more motors M202 so that the surgical tool 402 is positioned at a position corresponding to the position of the operation unit 74. This controls the operation of the link 404 so that the surgical tool 402 is positioned at a position corresponding to the position of the operation unit 74. At this time, the rotation angles detected by the one or more rotation angle detectors E202 are used for feedback control of the position of the surgical tool 402.

The attitude and movement of the operating unit 74 of the input device 2A are detected separately by an appropriate sensor (not shown) and input to the manipulator controller C2 via the input device controller C1. The manipulator controller C2 controls the surgical tool 402 so that it assumes an attitude corresponding to the attitude of the operating unit 74 of the input device 2A and performs an operation corresponding to the operation of the operating unit 74 of the input device 2A. The manipulator controller C2 is provided, for example, in an appropriate location on the hand control 100.

<Input device controller C1>
Fig. 10 is a functional block diagram showing an example of the configuration of the input device controller C1 of Fig. 9. Referring to Fig. 10, the input device controller C1 includes a position calculation unit 501, a gravity compensation amount calculation unit 502, a resistance force compensation amount calculation unit 503, a control unit (controller) 504, a servo amplifier (power converter) 505, a memory unit (storage unit) 506, and an input unit (input unit) 507.

The position calculation unit 501, gravity compensation amount calculation unit 502, resistance force compensation amount calculation unit 503, control unit 504, and memory unit 506 are configured, for example, by a computing unit (not shown) having a processor (not shown) and memory (not shown). Examples of the computing unit include a microcontroller. Examples of the processor include a CPU, MPU, FPGA (Field Programmable Gate Array), and PLC (Programmable Logic Controller). Examples of the memory include internal memory of the processor such as ROM and RAM, and external memory such as a hard disk drive.

The position calculation unit 501, gravity compensation amount calculation unit 502, resistance force compensation amount calculation unit 503, control unit 504, and memory unit 506 are functional blocks realized by the processor of the calculation unit reading and executing a predetermined control program stored in the memory of the calculation unit. In reality, the calculation unit operates as the position calculation unit 501, gravity compensation amount calculation unit 502, resistance force compensation amount calculation unit 503, control unit 504, and memory unit 506. Note that the position calculation unit 501, gravity compensation amount calculation unit 502, and resistance force compensation amount calculation unit 503 may be configured as hardware such as an electronic circuit. Furthermore, the input device controller C1 may be configured as a single calculation unit or multiple calculation units.

The position calculation unit 501 generates the position (position command signal) P of the operating unit 74 based on the input rotation angles AG of the first through seventh motors M1-M7. This calculation is well known, so its explanation is omitted.

The gravity compensation amount calculation unit 502 determines the posture of the master arm 10 based on the input rotation angles AG of the first through seventh motors M1 through M7, and calculates gravity cancellation torques that cancel out the gravity torques generated at each of the rotation axes R1 through R7 of the joints JT1 through JT7 due to the determined posture. In this case, the gravity compensation amount calculation unit 502 calculates the gravity torque determined for each of the rotation axes R1 through R7 from the obtained posture. For joints JT2, JT3, and JT5, which are equipped with coil springs, the gravity cancellation torque is determined as a torque in the opposite direction to the gravity torque minus the torque generated by the coil spring. For joints JT1, JT4, JT6, and JT7, which are not equipped with coil springs, the gravity cancellation torque is determined as a torque in the opposite direction to the gravity torque. The gravity cancellation torques of these first through seventh joints JT1 through JT7 are the gravity compensation amounts. The gravity compensation amount calculation unit 502 outputs the gravity compensation amount for the first to seventh joints JT1 to JT7 as a current command Ig for performing gravity compensation for the gravity compensation amount.

The resistance force compensation amount calculation unit 503 calculates the resistance force compensation amounts for the first through seventh joints JT1 through JT7 based on the input rotation angles AG of the first through seventh motors M1 through M7, and outputs these resistance force compensation amounts as current commands Id for performing resistance force compensation for those resistance force compensation amounts. The adder 518 adds the current command Ig for gravity compensation and the current command Id for resistance force compensation to generate the compensation current command Ic.

A servo amplifier (power converter) 505 outputs a drive current CR corresponding to the compensation current command Ic to each of the first to seventh motors M1 to M7. As a result, the first to seventh motors M1 to M7 generate a torque corresponding to the compensation current command Ic (current command Ig for gravity compensation+current command Id for resistance force compensation), and as a result, the posture of the master arm 10 is controlled so that it does not change due to gravity, and an operating force that is force-compensated for the resistance force of the master arm 10 is generated. Here, in this embodiment, gravity compensation is applied to the operating force, so the difference between the resistance force and the resistance force compensation amount is the operating force that is the force required by the operator to operate the master arm 10.

The memory unit 506 stores various data, etc. In particular, ranked force compensation amounts are pre-stored in the memory unit 506. Figure 12 is a graph showing an example of the ranks of the magnitude of ranked force compensation amounts. Referring to Figure 12, the force compensation amount is composed of a viscous force compensation amount and an inertial force compensation amount, with the viscosity adjustment coefficient Kd, which takes values from 0.0 to 1.0, representing the relative magnitude of the viscous force compensation amount, and the inertia adjustment coefficient Km, which takes values from 0.0 to 1.0, representing the relative magnitude of the inertia force compensation amount. These are then divided into five levels in increments of 0.2, and ranked from A to E in descending order of value.

Furthermore, when the specified force compensation amount is input from the input unit 507 in association with the operator ID as described below, the memory unit 507 stores this as the specified force compensation amount for each operator. Figure 13 is a graph showing an example of the specified force compensation amount for each operator. In Figure 13, X to Q represent the operator ID. Referring to Figure 13, the specified force compensation amount is made up of a viscous force compensation amount and an inertia force compensation amount. The viscosity adjustment coefficient Kd and inertia adjustment coefficient Km, which represent the viscous force compensation amount and the inertia force compensation amount, respectively, are made up of the specified force compensation amount for each operator by associating them with the operator ID.

The input unit 507 is a device through which the operator inputs various data to the control unit 504. The input unit 507 is composed of, for example, a keyboard, mouse, touch panel, etc. The operator uses the input unit 507 to input, for example, the rank of the force compensation amount, as well as the inertia adjustment coefficient Km, viscosity adjustment coefficient Kd, and operator ID as designated force compensation amounts for each operator. Therefore, the input unit 507 functions as an input device for designating the rank of the force compensation amount and an input device for identifying the operator corresponding to the designated force compensation amount. Note that this designated force compensation amount may also be configured to be input to the control unit 504 by input means other than the input unit 507. An example of such input means is input means via a data communications network.

The control unit 504 outputs the position (position command signal) P of the operation unit 74 generated by the position calculation unit 501 to the manipulator controller C2. The control unit 504 also processes various data input from the input unit 507 as appropriate.

In particular, when a rank A to E of the ranking force compensation amount is input from the input unit 507, the control unit 504 reads out the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd corresponding to the input rank A to E, and replaces the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd used respectively in the inertia adjustment coefficient multiplication unit 516 and viscosity adjustment coefficient multiplication unit 520 (described below) with the read inertia adjustment coefficient Km and viscosity adjustment coefficient Kd, respectively.

The control unit 504 also stores in the memory unit 506 the inertia adjustment coefficient Km, viscosity adjustment coefficient Kd, and operator ID (X to Q) that are input as a set from the input unit 507 as specified force compensation amounts for each operator, with the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd corresponding to the operator ID (X to Q). When an operator ID (X to Q) is input from the input unit 507, the control unit 504 reads out the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd corresponding to that operator ID from the memory unit 506, and replaces the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd used in the inertia adjustment coefficient multiplication unit 516 and viscosity adjustment coefficient multiplication unit 520, described below, with the read inertia adjustment coefficient Km and viscosity adjustment coefficient Kd, respectively. The operator may also be able to input an arbitrary inertia adjustment coefficient Km and viscosity adjustment coefficient Kd, and change them to the arbitrary inertia adjustment coefficient Km and viscosity adjustment coefficient Kd in the inertia adjustment coefficient multiplication unit 516 and the viscosity adjustment coefficient multiplication unit 520.

<Resistance force compensation amount calculation unit 503>
Fig. 11 is a block diagram showing the configuration of the resistance force compensation amount calculation unit 503 in Fig. 9. Fig. 11 shows the resistance force compensation amount calculation unit 503 corresponding to one of the first to seventh joints JT1 to JT7. In other words, resistance force compensation for the operating force is performed for each of the joints JT1 to JT7.

Referring to FIG. 11, the resistance force compensation amount calculation unit 503 includes a rotational angle delay unit 511, a first subtraction unit (speed acquisition unit) 512, a rotational angular velocity delay unit 513, a second subtraction unit (acceleration acquisition unit) 514, an inertia coefficient multiplication unit (inertia force compensation calculation unit) 515, an inertia adjustment coefficient multiplication unit 516, a primary filter 517, an addition unit 518, a viscosity adjustment coefficient multiplication unit (viscous force compensation amount calculation unit) 519, a viscosity adjustment coefficient multiplication unit 520, a primary filter 521, and first and second switches SW1 and SW2.

The rotation angle AG detected by the first to seventh rotation angle detectors E1 to E7 is sampled at a predetermined sampling interval. The rotation angle delay unit 511 delays the input rotation angle AG by one sampling interval. The first subtraction unit 512 subtracts the rotation angle AGd delayed by the rotation angle delay unit 511 from the rotation angle AG at the current time to generate the rotation angular velocity v. Here, the difference ΔAG between successive rotation angles AG corresponds to the rotation angular velocity v, which is the derivative of the rotation angle AG, when the sampling interval Δt is unit time.

The rotational angular velocity delay unit 513 delays the input rotational angular velocity v by one sampling interval. The second subtraction unit 514 subtracts the rotational angular velocity vd delayed by the rotational angular velocity delay unit 513 from the rotational angular velocity v at the current time to generate the rotational angular acceleration α. Here, the difference Δv between the successive rotational angular velocities v corresponds to the rotational angular acceleration α, which is the derivative of the rotational angular velocity v, when the sampling interval Δt is unit time.

The first switch SW1 allows or prevents transmission of the rotational angular acceleration α to the inertia coefficient multiplication unit 515 by turning it ON or OFF. The first switch SW1 is turned ON or OFF by the control unit 504 when an ON command or OFF command for the first switch SW1 is input from the input unit 507.

The inertia coefficient multiplier 515 multiplies the rotational angular acceleration α by the inertia coefficient M to generate the inertia force compensation amount fi. The inertia adjustment coefficient multiplier 516 multiplies the inertia force compensation amount fi by the inertia adjustment coefficient Km to generate the adjusted inertia force compensation amount. Here, the inertia adjustment coefficient Km is a numerical value in the range of 0.0 or more and 1.0 or less. The primary filter 517 removes noise caused by sampling from the adjusted inertia force compensation amount and outputs it as the current command Ii for inertia force compensation.

The time constant of the primary filter 517 may be adjustable. In this case, when the operator inputs the time constant of the primary filter 517 from the input unit 507, the control unit 504 replaces the time constant of the primary filter 517 with the input time constant. The reason for making the time constant adjustable in this way is that noise differs for each input device 2. The same applies to the primary filter 521, which will be described later.

On the other hand, the second switch SW2 allows or prevents transmission of the rotational angular velocity v to the viscosity coefficient multiplication unit 519 by turning it ON or OFF. The second switch SW2 is turned ON or OFF by the control unit 504 when an ON command or OFF command for the second switch SW2 is input from the input unit 507.

The viscosity coefficient multiplication unit 519 multiplies the rotational angular velocity v by the viscosity coefficient D to generate a viscosity compensation amount fv. The viscosity adjustment coefficient multiplication unit 520 multiplies the viscosity compensation amount fv by the viscosity adjustment coefficient Kd to generate an adjusted viscosity compensation amount. Here, the viscosity adjustment coefficient Kd is a numerical value in the range of 0.0 or more and 1.0 or less. The primary filter 521 removes noise and other artifacts caused by sampling from the adjusted viscosity compensation amount, and outputs it as a current command Iv for viscosity compensation. The current command Ii for inertia force compensation and the current command Iv for viscosity force compensation constitute the current command Id for resistance force compensation.

The time constant of the primary filter 521 may be adjustable. In this case, when the operator inputs the time constant of the primary filter 521 from the input unit 507, the control unit 504 replaces the time constant of the primary filter 521 with the input time constant.

An adder 518 adds the current command Id for resistance force compensation and the current command Ig for gravity compensation to generate a compensation current command Ic.
[Operation]
First, the operation of the right input device 2A and the surgical manipulator 202 will be described.

3 and 6, for example, the operator inserts their thumb and index finger into a pair of finger insertion portions 74a of the operation unit 74 of the right input device 2A. When the operator moves the operation unit 74 left and right, the arm unit 11 rotates left and right about the first rotation axis A1 of the first joint JT1. When the operator moves the operation unit 74 back and forth, the arm unit 11 rotates back and forth about the second rotation axis A2 of the second joint JT2. When the operator moves the operation unit 74 up and down, the arm unit 11 rotates up and down about the third rotation axis A3 of the third joint JT3. When the operator rotates the wrist unit 12 left and right, the wrist unit 12 rotates left and right about the fourth rotation axis A4 of the fourth joint JT4. When the operator operates the operation unit 74 to change the orientation (posture) of the operation unit 74, the operation unit 74 moves (takes up) in the desired direction. Therefore, the operator can operate the input device 2A as intended.

When the operation unit 74 of the right input device 2A is operated, this operation is converted into a position command signal P by the input device controller C1, and the manipulator controller C2 controls the operation of the selected arm unit 401 of the surgical manipulator 202 in accordance with this position command signal P so that the surgical tool 402 of the selected arm unit 401 is positioned at a position corresponding to the operation unit 74. As a result, the selected arm unit 401 of the surgical manipulator 202 operates in accordance with the operator's operation of the right input device 2A. The arm unit 401 is selected by operating the pedal 4 of the hand control 100. The left input device 2B operates in a similar manner.

Next, we will explain gravity compensation and resistance force compensation for the operating force of the right input device 2A. We will assume that the first and second switches SW1 and SW2 are ON.

Referring to Figures 3 and 10, when the operation unit 74 of the right input device 2A is operated, the gravity compensation amount calculation unit 502 in the input device controller C1 determines the posture of the master arm 10 based on the input rotation angles AG of the first through seventh motors M1 through M7, calculates a gravity cancellation torque that cancels out the gravity torque generated at each rotation axis R1 through R7 of each joint JT1 through JT7 due to that posture, and sets this gravity cancellation torque as the gravity compensation amount. It also sends this gravity compensation amount as a current command Ig for performing gravity compensation for that gravity compensation amount.

On the other hand, a resistance force compensation amount calculation unit 503 calculates resistance force compensation amounts for the first to seventh joints JT1 to JT7 based on the input rotation angles AG of the first to seventh motors M1 to M7, and outputs these resistance force compensation amounts as current commands Id for performing resistance force compensation for the resistance force compensation amounts. An adder 518 then adds the current command Ig for gravity compensation and the current command Id for resistance force compensation to generate a compensation current command Ic, and a servo amplifier 505 outputs a drive current CR corresponding to the compensation current command Ic to each of the first to seventh motors M1 to M7.

As a result, the first through seventh motors M1-M7 generate torque according to the current command Ig and current command Id, which in turn controls the posture of the master arm 10 so that it does not change due to gravity, and generates an operating force that is force-compensated for the resistance force of the master arm 10. Therefore, by appropriately adjusting the force compensation amount for this resistance force (resistance force compensation amount), the operating force can be finely adjusted.

<Adjustment of Resistance Force Compensation Amount>
10 to 12, the operator inputs one of ranks A to E of the ranked force compensation amount according to his/her preference through input unit 507. Then, control unit 504 reads out the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd corresponding to rank A to E from storage unit 506, and replaces the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd used in inertia adjustment coefficient multiplication unit 516 and viscosity adjustment coefficient multiplication unit 520 with the read inertia adjustment coefficient Km and viscosity adjustment coefficient Kd, respectively. This allows the operating force to be adjusted to the operator's preference.

<Adjustment of Resistance Force Compensation Amount When Multiple Operators Are Present>
Next, adjustment of the resistance force compensation amount when there are multiple operators will be described.

Referring to Figures 10, 11, and 13, when there are multiple operators, for example, each operator is assigned an operator ID (X to Q). Each operator inputs their desired inertia adjustment coefficient Km and viscosity adjustment coefficient Kd (specified force compensation amount) and their own operator ID (X to Q) in advance via the input unit 507. The control unit 504 then stores the input inertia adjustment coefficient Km, viscosity adjustment coefficient Kd, and operator ID (X to Q) in the memory unit 506, correlating the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd with the operator ID (X to Q).

Then, the operator who actually intends to operate the input device 2 (here, the right input device 2A) of the surgical manipulator 202 inputs their own operator ID (X to Q) from the input unit 507. The control unit 504 then reads out the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd corresponding to that operator ID (X to Q) from the memory unit 506, and replaces the inertia adjustment coefficient Km and viscosity adjustment coefficient Kd used in the inertia adjustment coefficient multiplication unit 516 and the viscosity adjustment coefficient multiplication unit 520, respectively, with the read inertia adjustment coefficient Km and viscosity adjustment coefficient Kd. This allows the operating force to be set to the operating force desired by the operator.

<When you want to set the resistance force compensation amount to zero>
10 and 11 , when it is desired to set the inertial force compensation amount to zero, the operator inputs an OFF command for the first switch SW1 from the input unit 507. This causes the control unit 504 to turn off the first switch SW1, and the inertial force compensation amount becomes zero. Furthermore, when it is desired to set the viscous force compensation amount to zero, the operator inputs an OFF command for the second switch SW2 from the input unit 507. This causes the control unit 504 to turn off the second switch SW2, and the viscous force compensation amount becomes zero. This makes it possible to easily set the operating force for each joint.

As a result, the operator can easily and precisely adjust the operating force to a level that is comfortable for them.

(Other embodiments)
In the above embodiment, the arm unit 11 has three joints, but the arm unit 11 may have one or more joints.

In the above embodiment, the wrist unit 12 has four joints, but the wrist unit 12 may have one or more joints.

In the above embodiment, the rotational angular velocity and rotational angular acceleration were obtained from the rotational angle of the power transmission element, but the speed (angular velocity) and acceleration (each acceleration) of the power transmission element may also be obtained using a speed sensor and an acceleration sensor.

Many modifications and alternative embodiments will be apparent to those skilled in the art from the above description. Therefore, the above description should be construed as illustrative only.

The input device for a surgical manipulator of the present invention is useful as an input device for a surgical manipulator that allows for precise adjustment of operating force.

1 Main body 2 Input device 2A Right input device 2B Left input device 3 Support member 4 Pedal 5 Display unit 10 Master arm 11 Arm unit 12 Wrist unit 21 Base body 22 First link 23 Second link 24 Third link 25 Swing member 26 Auxiliary links 51 to 53 Bearing 62 Connecting member 71 Fourth link 72 Fifth link 73 Sixth link 74 Operation unit 74a Finger insertion unit 81 to 84 Bearing 100 Hand control 200 Robot-assisted surgery system 201 Positioner 202 Surgical manipulator 203 Operating table 204 Patient 401 Arm unit 402 Surgical tool 404 Link 501 Position calculation unit 502 Gravity compensation amount calculation unit 503 Resistance force compensation calculation unit 504 Control unit 505 Servo amplifier 506 Memory unit 507 Input units A1 to A7 1st to 7th rotation axes A9 to A11, 9th to 11th rotation axes AG, rotation angle CR, drive current E1 to E7, 1st to 7th rotation angle detectors G1 to G4, bevel gear mechanisms JT1 to JT7, 1st to 7th joints M1 to M7, 1st to 7th motors P, position of operation unit R1 to R7, 1st to 7th rotation axes R9 to R11, 9th to 11th rotation axes S1 to S7, main shaft SP1, tension coil spring SP2, compression coil spring SW1, first switch SW2, second switch

Claims (12)

a master arm having a joint and provided at its tip with an operation unit operated by an operator;
a motor that drives the joint of the master arm via a power transmission element;
a controller for controlling the operation of the motor;
a storage device that stores information about ranked adjusted inertia force compensation amounts obtained by multiplying an inertia force compensation amount obtained by multiplying an acceleration or a rotational angular acceleration of the power transmission element that moves in response to operation of the operation unit by the operator by an inertia coefficient, and a plurality of adjusted inertia force compensation amounts that are each multiplied by a plurality of inertia adjustment coefficients that are greater than 0, and ranking the ranked adjusted inertia force compensation amounts in order of magnitude;
an inertial force compensation amount input device for specifying one of the two or more ranked and adjusted inertial force compensation amounts,
The controller
calculating the inertial force compensation amount, which is a magnitude of a force that cancels out a part or all of the inertial force generated in the master arm due to the acceleration or the rotational angular acceleration, based on the acceleration or the rotational angular acceleration;
an input device for a surgical manipulator configured to adjust the amount of inertial force compensation to the amount of inertial force compensation corresponding to the ranked and adjusted amount of inertial force compensation designated by the inertial force compensation amount input device. a storage device that stores designated inertial force compensation amounts corresponding to each of a plurality of operators; and a designated inertial force compensation amount input device that identifies the operator corresponding to the designated inertial force compensation amount,
2. The input device for a surgical manipulator according to claim 1, wherein the controller is configured to adjust the amount of inertial force compensation to the specified amount of inertial force compensation corresponding to the operator specified by the specified inertial force compensation amount input device. the controller includes an acceleration acquisition unit that acquires the acceleration or the rotational angular acceleration of the power transmission element, an inertia force compensation amount calculation unit that calculates the inertia force compensation amount based on the acceleration or the rotational angular acceleration acquired by the acceleration acquisition unit and the inertia of the master arm, and an inertia force compensation amount power converter that supplies power to the motor for force compensation of the inertia force compensation amount,
3. The input device for a surgical manipulator according to claim 1, comprising: the master arm has a plurality of the joints,
the input device includes a plurality of power transmission elements; and a plurality of motors each driving a respective joint via the power transmission element;
4. The input device for a surgical manipulator according to claim 1, wherein the controller is configured to calculate, for each of the joints, the amount of inertia force compensation of a part driven by each of the joints based on the acceleration or the rotational angular acceleration, and to control operation of each of the motors so as to perform force compensation for the amount of inertia force compensation. An input device for a surgical manipulator according to claim 4, wherein the controller is configured to adjust the amount of inertial force compensation for each joint of the part driven by the joint. a master arm having a joint and provided at its tip with an operation unit operated by an operator;
a motor that drives the joint of the master arm via a power transmission element;
a controller for controlling the operation of the motor;
a memory that stores information about ranked adjusted viscous force compensation amounts obtained by multiplying a viscosity coefficient by a speed or a rotational angular velocity of the power transmission element that moves in response to the operation of the operation unit by the operator, and ranking a plurality of adjusted viscous force compensation amounts obtained by multiplying the viscosity compensation amount by a plurality of viscosity adjustment coefficients that are greater than 0 in order of magnitude;
a viscous force compensation amount input device for specifying one of the two or more ranked and adjusted viscous force compensation amounts,
The controller
calculating the viscous force compensation amount, which is a magnitude of a force that cancels out a part or all of a viscous force generated in the master arm due to the velocity or the rotational angular velocity, based on the velocity or the rotational angular velocity;
an input device for a surgical manipulator configured to adjust the viscous force compensation amount to the viscous force compensation amount corresponding to the ranked and adjusted viscous force compensation amount specified by the viscous force compensation amount input device. a memory that stores a designated viscous force compensation amount corresponding to each of the plurality of operators; and a designated viscous force compensation amount input device that identifies the operator corresponding to the designated viscous force compensation amount,
7. The input device for a surgical manipulator according to claim 6, wherein the controller is configured to adjust the viscous force compensation amount to the specified viscous force compensation amount corresponding to the operator specified by the specified viscous force compensation amount input device. The input device for a surgical manipulator according to claim 6 or 7, wherein the controller comprises: a velocity acquisition unit that acquires the velocity or the rotational angular velocity of the power transmission element; a viscous force compensation amount calculation unit that calculates the viscous force compensation amount based on the velocity or the rotational angular velocity acquired by the velocity acquisition unit and the viscosity of the master arm; and a viscous force compensation amount power converter that supplies power to the motor for force compensation of the viscous force compensation amount. the master arm has a plurality of the joints,
the input device includes a plurality of power transmission elements; and a plurality of motors each driving a respective joint via the power transmission element;
9. The input device for a surgical manipulator according to claim 6, wherein the controller is configured to calculate, for each of the joints, the amount of viscous force compensation for a portion driven by the joint based on the velocity or the rotational angular velocity, and to control operation of each of the motors so as to perform force compensation for the viscous force compensation amount. An input device for a surgical manipulator according to claim 9, wherein the controller is configured to adjust the amount of viscous force compensation for each joint in the portion driven by the joint. An input device for a surgical manipulator according to any one of claims 1 to 10, wherein the controller is further configured to control the operation of the motor so that the attitude of the master arm does not change due to gravity. An input device for a surgical manipulator according to any one of claims 1 to 11, wherein the controller is further configured to calculate the position of the operating unit based on the position of the power transmission element that moves in response to the operator's operation of the operating unit, and to output this calculated position of the operating unit to the surgical manipulator.