WO2025057608A1 - Coupling device and medical robot device - Google Patents

Abstract

Provided is a coupling device for connecting a driven shaft and a drive shaft.　The coupling device comprises: a linear motion driven shaft part; a linear motion drive shaft part; and a coupling part for coupling the driven shaft part and the drive shaft part through surface joining. The driven shaft part comprises a linear slider including a first rotor and a first stator, and the drive shaft part comprises a linear actuator including a second rotor and a second stator. The coupling part couples the first rotor and the second rotor through surface joining and the first stator and the second stator through surface joining so that the first rotor and the second rotor move in the same direction.

Description

Coupling device and medical robot device

The technology disclosed in this specification (hereinafter referred to as "the present disclosure") relates to a coupling device that connects a driven part equipped with an end effector to a driving part including a motor that drives the end effector, and a medical robot device that uses the coupling device.

Currently, robotics technology is making inroads in various industrial fields, including medicine. In general, a robot arm (manipulator) is equipped with a driven part consisting of an end effector with one or more degrees of freedom at its distal end, and a driving part consisting of a motor that drives the end effector. In order to adapt a single manipulator to multiple applications, it is preferable for the end effector to be interchangeable. In this case, a coupling structure is required to connect the drive shaft of the power source and the driven shaft on the end effector side.

For example, a coupling structure has been proposed for a medical manipulator system that connects a surgical tool unit equipped with a surgical tool at its tip to a drive unit that drives the surgical tool (see Patent Document 1). In this medical manipulator system, the surgical tool unit and drive unit are connected via an adapter.

The coupling structure that connects the driven part and the driving part must satisfy engineering requirements, such as easy attachment and detachment for replacing the end effector, good power transmission efficiency, little backlash, and the ability to connect with good reproducibility. When applied to the medical field, an additional medical requirement is that the cleanliness of the driven part that is detached and replaced must be guaranteed.

JP 2022-27324 A

The objective of this disclosure is to provide a coupling device that connects a driven part equipped with an end effector to a driving part including a motor that drives the end effector while satisfying engineering requirements, as well as a medical robot device that utilizes the coupling device.

The present disclosure has been made in consideration of the above problems, and a first aspect thereof is:
A linear driven shaft portion;
A linear drive shaft portion;
a connecting portion that connects the driven shaft portion and the driving shaft portion by surface joining;
A coupling device comprising:

The driven shaft portion includes a linear slider including a first rotor and a first stator, and the driving shaft portion includes a linear actuator including a second rotor and a second stator. The connecting portion connects the first rotor and the second rotor, and the first stator and the second stator, respectively, by surface joints so that the moving directions of the first rotor and the second rotor are the same.

The connecting portion uses the attractive force of magnets to connect the first rotor and the second rotor, and the first stator and the second stator. Specifically, the connecting portion includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft portion, and a plurality of second magnets attached to each of the second rotor and the second stator of the drive shaft portion, and the second magnets are disposed on the second stator at locations corresponding to the first magnets attached to the first stator. Furthermore, one of the first stator and the second stator may have a positioning pin, and the other may have a pin hole that fits with the positioning pin.

In addition, a second aspect of the present disclosure is
a first robotic device supporting a surgical tool at a distal end;
a second robotic device coupled to the first robotic device;
Equipped with
a linear motion driven shaft portion of the first robot device and a linear motion drive shaft portion of the second robot device are connected by a surface joint;
The first robot device operates the surgical tool by power transmitted from the drive shaft portion to the driven shaft portion.
It is a medical robotic device.

The first robotic device supports the surgical tool so that it has a remote center of motion. The second robotic device is detachably connected to the first robotic device.

In addition, a third aspect of the present disclosure is
A link mechanism that supports a surgical tool at a distal end;
a linear driving shaft portion detachably connected to the linear driving shaft portion by surface contact;
Equipped with
The linear motion driven shaft drives the link drive unit by power transmitted from the linear motion drive shaft.
It is a medical robotic device.

This disclosure makes it possible to provide a coupling device and a medical robot device that connect a driven part and a driving part while satisfying not only engineering requirements but also medical requirements.

Note that the effects described in this specification are merely examples, and the effects brought about by this disclosure are not limited to these. Furthermore, this disclosure may have additional effects in addition to the effects described above.

Further objects, features and advantages of the present disclosure will become apparent from the following detailed description based on the embodiments and the accompanying drawings.

FIG. 1 is a diagram showing a basic configuration of a coupling device 100 according to the present disclosure (a separated state before a driven shaft and a driving shaft are coupled to each other). FIG. 2 is a diagram showing a basic configuration of the coupling device 100 according to the present disclosure (in a state in which the driven shaft and the driving shaft are coupled). FIG. 3 illustrates a basic configuration (with thrust and load applied) of a coupling device 100 according to the present disclosure. FIG. 4 is a diagram for explaining alignment required during coupling in the coupling device 100. As shown in FIG. FIG. 5 is a diagram for explaining a method for automatically coupling a rotor in the coupling device 100. As shown in FIG. FIG. 6 shows a variation of the coupling device 100 with a locating pin. FIG. 7 is a diagram illustrating an articulated link configuration of a robotic arm 700 to which the present disclosure can be applied. FIG. 8 is a side view of a robot arm 700 having an origami structure. FIG. 9 is a perspective view of a robot arm 700 having an origami structure viewed from the distal end. FIG. 10 is a diagram showing the external configuration of the drive unit 1000. As shown in FIG. FIG. 11 is a diagram showing the joint link configuration of the drive unit 1000. FIG. 12 is a diagram showing the bottom surface of the robot arm 700. FIG. 13 is a view showing the top surface of the drive unit 1000. As shown in FIG. FIG. 14 is a diagram showing the operation of connecting the robot arm 700 to the drive unit 1000. As shown in FIG. FIG. 15 is a diagram showing the operation of connecting the robot arm 700 to the drive unit 1000. As shown in FIG. FIG. 16 is a diagram showing the operation of connecting the robot arm 700 to the drive unit 1000. As shown in FIG. FIG. 17 is a diagram showing a modified example of the coupling device (an example for compensating for the height discrepancy). FIG. 18 is a view showing another modified example of the coupling device. FIG. 19 is a view showing still another modified example of the coupling device. FIG. 20 is a diagram showing an example of a schematic configuration of a medical robot system 2000. FIG. 21 is a diagram showing an example of the functional configuration of a medical robot system 2000. FIG. 22 is a diagram showing a general configuration of a linear slider 2200.

The following describes the embodiments of the present disclosure with reference to the drawings in the following order:

A. Overview B. Basic configuration C. Implementation example C-1. Configuration of robot arm C-2. Coupling structure applied to robot arm C-3. Features D. Modified example of coupling device E. Application example to medical robot system E-1. Schematic configuration of medical robot system E-2. Functional configuration of medical robot system E-3. Features

A. Overview In the mechatronics field, the transmission of power from the drive shaft of a motor to the driven shaft on the end effector side is one of the important issues. The coupling structure that connects the driven shaft and the drive shaft is required to satisfy engineering requirements such as easy attachment and detachment to easily replace the end effector even during work, good power transmission efficiency, small backlash, and good reproducibility of connection. Furthermore, in the medical field, in addition to the engineering requirements, the coupling structure is also required to ensure the cleanliness of the driven part side that is attached, detached, and replaced as a medical requirement.

When applied to the medical field, the driven shaft side, which is equipped with a surgical tool as an end effector, is in a sterilized clean area, while the other drive shaft side is separated from the clean area by being covered with a drape, for example, and it is required to maintain the cleanliness of the driven shaft side. For this reason, the components of the coupling part that connects the driven shaft and drive shaft must be sterilizable.

Moreover, in general surgical procedures, multiple surgical tools are used, so the surgical tools must be replaced smoothly. For this reason, a coupling structure that allows easy attachment and detachment of the driven shaft and driving shaft and is highly reproducible is required. For example, in the case of a coupling structure in which the driven shaft is attached to the driving shaft using a screw, it is difficult for non-engineers such as the surgeon or assistant to precisely screw it in place, and it also becomes difficult to smoothly replace surgical tools during surgery.

In the case of a coupling structure in which both the driving shaft and the driven shaft adopt a rotational system, the rotational force of the driving shaft generated by the rotary motor is transmitted to the driven shaft via the coupling structure. In this case, it is necessary to connect the driving shaft and the driven shaft coaxially. Therefore, it is necessary to perform the orientation of the two rotational axes (e.g., pan and tilt) and the alignment of the two translational axes perpendicular to the rotational axes, making it difficult to ensure precision. In addition, in the case of the rotational system, a backlash occurs because a reducer is used on at least one of the driving shaft side or the driven shaft side, making it difficult to transmit power without backlash. Low-backlash couplers are known in the industry, but their structure is complex, and there are concerns about the impact on costs and risk of failure due to the increased number of parts. In addition, such couplers have a complicated structure, making them difficult to sterilize (for example, gas does not easily penetrate during gas sterilization, making them unable to be sterilized sufficiently).

In consideration of the above-mentioned problems, the present disclosure proposes a coupling device that can precisely connect a driving shaft and a driven shaft and can also be applied to the medical field (medical robot systems, etc.). The coupling device according to the present disclosure employs a linear motion system for both the driving shaft and the driven shaft, and adopts a configuration in which the driving shaft and the driven shaft are connected by a surface joint.

Both the driving shaft and the driven shaft use linear sliders to achieve a linear motion system. The linear slider itself is a mechanical component well known in the industry. FIG. 22 shows a schematic diagram of a general configuration of a linear slider 2200. The illustrated linear slider 2200 is composed of the components of a stator 2201 and a rotor 2202. The stator 2201 is fixed to a mechanical ground, for example, and has a guide rail (details not shown in FIG. 22) that guides and supports the rotor 2202. The rotor 2202 is placed on the stator 2201 and reciprocates along the guide rail in the longitudinal direction of the stator 2201. When the linear slider 2200 is on the driving shaft side, it is further equipped with a motor (not shown in FIG. 22) that serves as a drive source for operating the rotor 2202, and can also be called a "linear actuator." On the other hand, when the linear slider 2200 is on the driven shaft side, the rotor 2202 moves linearly in the longitudinal direction of the stator 2201 due to the power transmitted from the outside (the driving shaft side). In this specification, the member that moves (linearly or rotatingly) relative to the stator in the linear slider and linear actuator is called the "rotor."

The coupling device according to the present disclosure is configured by arranging the linear actuator on the drive shaft side and the linear slider on the driven shaft side facing each other so that their longitudinal directions (i.e., the direction of movement of each rotor) are aligned, and connecting them to each other by surface bonding. Therefore, when the rotor on the drive shaft side is reciprocated in the longitudinal direction, the rotor on the driven shaft side also moves together with it, thereby achieving power transmission from the drive shaft to the driven shaft.

B. Basic Configuration Figures 1 and 2 show a schematic diagram of the basic configuration of a coupling device 100 according to the present disclosure. The coupling device 100 is composed of a linear slider 110 on the driven shaft side and a linear actuator 120 on the driving shaft side. Figure 1 shows a separated state before the linear slider 110 and the linear actuator 120 are coupled, and Figure 2 shows a coupled state in which the linear slider 110 and the linear actuator 120 are coupled by surface bonding.

The linear slider 110 on the driven shaft side has a rotor 111, which is the movable part, and a stator 112 that guides and supports the rotor 111 in the longitudinal direction. An end effector such as a surgical tool (not shown in FIG. 1) is attached to the linear slider 110.

On the other hand, the linear actuator 120 on the drive shaft side includes a rotor 121, which is the movable part, a stator 122 that guides and supports the rotor 121 in the longitudinal direction, and a motor (not shown in FIG. 1) that is the drive source that operates the rotor 121.

The coupling device 100 is configured by arranging the linear slider 110 and the linear actuator 120 facing each other so that their longitudinal directions (i.e., the directions of movement of the rotor 111 and the rotor 121) are aligned, and connecting them to each other by surface bonding.

The surface-to-surface connection between the linear slider 110 and the linear actuator 120 utilizes the attraction force of magnets. As shown in FIG. 1, on the linear slider 110 side, magnets 113 and 114 are arranged at both ends of the longitudinal direction of the stator 112, and magnet 115 is arranged on the upper surface of the rotor 111. On the linear actuator 120 side, magnets 123 and 124 are arranged at both ends of the longitudinal direction of the stator 122, and magnet 125 is arranged on the upper surface of the rotor 121. The polarity of each magnet is set so that an attraction force is generated between the opposing magnets 113 and 123, between the magnets 114 and 124, and between the magnets 115 and 125. Therefore, simply by bringing the linear slider 110 and the linear actuator 120 close to each other in an opposing relationship, the attraction force between the corresponding magnets realizes the connection between the linear slider 110 and the linear actuator 120, that is, the surface-to-surface connection between the driven shaft and the driving shaft, as shown in FIG. 2.

One method for fixing the magnets to the rotor and stator components is adhesion. By using a heat-resistant magnet, it is possible to use a thermosetting adhesive. In this case, it is also possible to use a high-pressure steam sterilization device to sterilize the coupling device 100.

In the connected state of the rotor 111 on the driven shaft side and the rotor 121 on the driving shaft side as shown in FIG. 2, when the rotor 121 is driven, a frictional force corresponding to the adhesive force between the magnets 115 and 125 is generated in the thrust direction. The thrust direction is the direction in which the rotor 121 moves longitudinally on the stator 122. If the adhesive force between the magnets 115 and 125 is F and the friction coefficient is μ, the frictional force N generated in the thrust direction is N = μF. As shown in FIG. 3, if a load in the opposite direction to the thrust direction of the rotor 121 is applied to the rotor 111, when the relationship of "thrust ≧ load" exists in the thrust direction, power can be transmitted from the driving shaft side (linear actuator 120) to the driven shaft side (linear slider 110) without backlash.

The alignment adjustment when connecting the driven shaft and the driving shaft in the coupling device 100 will be explained with reference to FIG. 4. As described above, the linear slider 110 on the driven shaft side and the linear actuator 120 on the driving shaft side are connected by a surface joint that utilizes the attractive force of magnets. FIG. 4 shows a side view and a top view of the coupling device 100 when surface jointed.

On the linear slider 110 side, magnets 113 and 114 are arranged at both ends of the stator 112 in the longitudinal direction, and magnet 115 is arranged on the top surface of the rotor 111. On the linear actuator 120 side, magnets 123 and 124 are arranged at both ends of the stator 122 in the longitudinal direction, and magnet 125 is arranged on the top surface of the rotor 121. The polarity of each magnet is set so that an attractive force is generated between the opposing magnets 113 and 123, between magnets 114 and 124, and between magnets 115 and 125.

When the linear slider 110 and the linear actuator 120 are brought close to each other facing each other, the magnetic attraction between the corresponding magnets connects the linear slider 110 and the linear actuator 120 through a surface joint. The alignment at this time is only the orientation of one axis of rotation in the longitudinal direction of the stator 112 on the linear slider 110 side and the stator 122 on the linear actuator 120 side, as shown in the top view of Figure 4, and this alignment is achieved by the magnetic attraction.

In the case of a coupling structure that employs a rotational method, when coupling, it is necessary to perform the orientation of the two rotational axes of the output shaft on the driving side and the input shaft on the driven side, and the alignment of the two translational axes that are perpendicular to the rotational axes (as described above). In contrast, the coupling device 100 according to the present disclosure employs a linear motion method and connects the driven shaft and driving shaft through surface contact, so that only one axis of rotation in the longitudinal direction is required for orientation, and the load of alignment is significantly reduced.

In addition, when the stator 112 of the linear slider 110 and the stator 122 of the linear actuator 120 are connected with their longitudinal orientations aligned, as shown in FIG. 5(a), the rotors 111 and 121 may not be connected because the positions of the rotors 111 and 121 are misaligned. Even in such a case, as shown in FIG. 5(b), the rotor 121 on the linear actuator 120 side can be moved in the longitudinal direction of the stator 122, for example, by a return-to-origin operation, thereby realizing automatic connection of the rotors 111 and 121. This is because, as shown in FIG. 5(c), when the rotors 111 and 121 are aligned with the other rotor 111, the magnetic attraction of the magnets 115 and 125 connects the rotors 111 and 121.

As described with reference to FIG. 4, the coupling device 100 according to the present disclosure requires only one axis of rotation in the longitudinal direction for alignment during coupling. This alignment can be made even easier by using a positioning pin. FIG. 6 shows a modified example of the coupling device 100 with a positioning pin. In the illustrated example, positioning pins 601 and 602 are attached to the stator 122 of the linear actuator 120 on the driving shaft side. On the other hand, pin holes 611 and 612 are drilled in the stator 112 of the linear slider 110 on the driven shaft side at locations opposite the positioning pins 601 and 602. Therefore, by coupling the linear slider 110 and the linear actuator 120 so that the positioning pins 601 and 602 are fitted into the pin holes 611 and 612, respectively, alignment between the stators 112 and 122 can be easily achieved. The top of Figure 6 shows the linear slider 110 and the linear actuator 120 in a separated state before they are connected, and the bottom of Figure 6 shows the linear slider 110 and the linear actuator 120 in a connected state using the engagement of the positioning pin 601 and the positioning pin 602 with the pin hole 611 and the pin hole 612.

In the example shown in Figure 6, a positioning pin is attached to the drive shaft side and a pin hole is provided on the driven shaft side, but the opposite may be true, with a positioning pin attached to the driven shaft side and a pin hole provided on the drive shaft side. In this case, however, an additional step of attaching a positioning pin is required each time the driven shaft side is replaced. Therefore, from the perspective of reducing the number of steps, a configuration in which a positioning pin is attached to the drive shaft side and a pin hole is provided on the driven shaft side, as shown in Figure 6, is more preferable.

The features of the coupling device 100 disclosed herein are summarized below.

(1) The coupling device 100 employs a linear motion system for the drive shaft and driven shaft to be coupled, and is configured to connect the drive shaft and driven shaft by surface contact. This reduces the degree of freedom required for alignment and orientation of the drive shaft and driven shaft, and reduces the workload of attachment and detachment.
(2) The coupling device 100 is configured to use the attractive force and frictional force of magnets to couple and transmit thrust between the drive shaft and the driven shaft, which enables power to be transmitted from the drive shaft to the driven shaft without backlash, improving the accuracy of driving the driven shaft.
(3) The coupling device 100 does not use mechanical parts such as screws to connect the drive shaft and the driven shaft. Therefore, the process of replacing the driven shaft on which an end effector such as a surgical tool is mounted can be simplified. In addition, even non-engineers such as surgeons and assistants can realize coupling with high reproducibility.
(4) The structure of the coupling device 100 is generally simplified. Therefore, the manufacturing process is simplified, leading to reduced costs. In addition, since the coupling device 100 has a simple structure that is not complicated, gas can easily penetrate during gas sterilization, facilitating the sterilization process.

C. Implementation Example In this section C, an implementation example of a robot arm to which a linear motion coupling device according to the present disclosure is applied will be described.

C-1. Robot arm configuration Fig. 7 shows the joint link configuration of a robot arm 700 to which the present disclosure can be applied. In the figure, the joint axis is represented by "q" and the link is represented by "l", and the serial numbers identifying each joint q and each link l are represented by subscripts in the lower left corner. However, there are two types of joint axes: rotary axes and linear axes.

The robot arm 700 is assumed to be a medical robot arm applied to surgical operations such as ophthalmic surgery (or fundus surgery), etc. That is, the tip of the end effector l _ee, which is the tip (distal end) link, is a surgical tool T such as forceps, and power given to the linear motion shaft q ₂₀ and the linear motion shaft q ₂₁ arranged near the bottom (mechanical ground) is transmitted by a slider link mechanism to give the end effector l _ee translational and rotational degrees of freedom.

The robot arm 700 roughly constitutes a parallel link mechanism, and the position where the longitudinal axis of the end effector l _ee intersects with the mechanical ground becomes the remote center of motion RCM of the end effector l _ee . Therefore, when the robot arm 700 is applied to ophthalmic surgery, the robot arm 700 is positioned so that the trocar inserted into the sclera (white of the eye) of the eye coincides with this RCM, thereby reducing the load applied to the insertion part when the end effector l _ee , which is a surgical tool, is operated or the eye moves, thereby realizing minimally invasive surgery. In other words, by moving the linear axis _q20 in a straight line, the end effector l _ee can be translated in the longitudinal direction (insertion direction) while remaining inserted in the trocar positioned on the RCM, and by moving the linear axis _q21 in a straight line, the end effector l _ee can be rotated while the position of the trocar is fixed.

The linear motion axis _q20 and the linear motion axis _q21 can each be configured as a linear slider on the driven shaft side in the coupling device according to the present disclosure, and can be linearly operated by connecting them to a linear actuator (neither shown) on the driving shaft side installed outside the robot arm 700 (specifically, on the robot device main body side on which the robot arm 700 is mounted). However, the specific configuration of the linear motion axis _q20 and the linear motion axis _q21 and details of the coupling with the driving shaft side will be described later.

While the linear axis _q20 and the linear axis _q21 are active axes that are driven by being connected to the drive axis, the other linear axis _q19 is a passive axis. This passive axis _q19 is inserted between the link l _ee and the link _l17 , and connects the joint axes _q10 and _q11 . The passive axis _q19 has the role of keeping the link _l15 and the link _l16 (and the link _l17 ) on a straight line while the end effector l _ee is translated and rotated by the operation of the linear axis _q20 and the linear axis _q21 , and of connecting the joint axes _q10 and _q11 at both ends of these links in a freely expandable and contractible manner. The passive axis _q19 performs linear motion so that the YZ plane passing through the joint axes _q10 , _q11 , and _q14 is constrained.

The robot arm 700 having the joint link configuration as shown in Fig. 7 can also be assembled like origami paper. Figs. 8 and 9 show an example of the configuration of the robot arm 700 using an origami structure. Fig. 8 is a side view of the robot arm 700 having an origami structure viewed from the side, and Fig. 9 is a perspective view of the robot arm 700 having an origami structure viewed from the distal end side. The linear motion axis _q20 and the linear motion axis _q21 move linearly by the transmission of power from an external source, but in Figs. 8 and 9, the linear motion axis _q20 and the linear motion axis _q21 are omitted for simplicity.

First, the origami structure will be described. The robot arm 700 having the origami structure is constructed using plate-like members that can be bent to have a hinge structure. The bent portions of the plate-like members function as (rotational) joint axes, and the portions connecting the bent portions function as links. The joint portions of the plate-like members are flexible and configured to be elastically deformable, and function as a hinge structure. The joint portions of the plate-like members are softer than the link portions, and conversely, the link portions of the plate-like members have higher rigidity than the joint portions. For example, the thickness of the joint portions of the plate-like members is smaller than the thickness of the link portions. The joint portions may further include one or more holes (micropores). By having the joint portions of the plate-like members be thinner or include holes, the joint portions can be made softer than the link portions, making them easier to bend.

The plate-like member can be made of materials such as carbon, iron, or composite materials. Different materials may be used for the joint and link parts, and the joint parts may be made of a softer material (a material with a different Young's modulus) than the link parts. Examples of soft materials used for the joint parts include polyimide, rubber, silicone, and elastomers.

Next, the link structure of the robot arm 700 will be described. The robot arm 700 is a parallel link mechanism that extends in the XZ plane, and includes multiple joint axes and links as shown in FIG. 7. This parallel link mechanism has two degrees of freedom in the X-axis and Z-axis directions, but no degree of freedom in the Y-axis direction.

Joint axes _q1 to _q21 are illustrated as multiple joint axes of the parallel link mechanism (however, in Figs. 8 and 9, illustration of linear axis _q20 and linear axis _q21 is omitted). Of these, joint axes _q1 , _q2 , _q7 , and _q10 are disposed on the base (mechanical ground) of the robot arm 700. The base of the robot arm 700 is the end opposite to the distal end (however, in Figs. 8 and 9, illustration of the end effector l _ee at the distal end is omitted).

As shown in Fig. 7, the linear motion of the linear axis _q21 , which is an active axis, is transmitted through link _l12 , joint axis _q18 , link _l11 , and joint axis _q17 to rotate link _l4 around joint axis _q1 . The linear motion of the linear axis _q20 , which is an active axis, is transmitted through link _l8 , joint axis _q16 , link _l7 , and joint axis _q15 to rotate link _l9 around joint axis _q7 . The linear axis _q20 and the linear axis _q21 , which are active axes, are each configured as a linear slider on the driven axis side in the coupling device according to the present disclosure, and can be linearly moved by being coupled to a linear actuator on the driving axis side (neither of which is shown in Figs. 7 to 9) installed below the base part of the robot arm 700. However, the specific configuration of the linear motion shaft _q20 and the linear motion shaft _q21 and the details of the coupling with the drive shaft side will be described later.

A plurality of links l ₁ to l ₁₅ and a distal end link (end effector) l _ee (however, l _ee is not shown in FIGS. 8 and 9 ) each extend in the XZ plane direction and connect the joint axes. Specifically, link l ₁ connects joint axis q ₁ and joint axis q _2. Link l ₂ connects joint axis q ₂ and joint axis q _3. Link l ₃ connects joint axis q ₃ and joint axis q _4. Link l ₄ connects joint axis q ₁ and joint axis q _4. Link l ₅ connects joint axis q ₃ and joint axis q _5. Link l ₆ connects joint axis q ₅ and joint axis q _13. Link l ₇ connects joint axis q ₄ and joint axis q _6. Link l ₁₄ connects joint axis q ₃ and joint axis q ₄ . Link _l15 connects joint axis _q12 and joint axis _q13 .

The robot arm 700 includes a parallel link mechanism _pl1 located on the base side, a parallel link mechanism _pl2 located on the distal end side, and a parallel link mechanism pl3 located between the parallel link mechanisms _{pl1 and pl2 .} The parallel link mechanism _pl1 located on the base side is composed of joint axis _q1 , joint axis _q2 , joint axis _q3 , joint axis _q4 , link _l1 , link l2, link _l3 , and _{link l4} . The parallel link mechanism _pl2 located on the distal end side is composed of joint axis _q11 , joint axis _q12 , joint axis _q13 , joint axis _q14 , link _l12 , link _l14 , link l6, _{and link l15 .} The parallel link mechanism pl3, located between the parallel link mechanism _pl1 and the parallel link mechanism _{pl2 ,} is composed of joint axis _q3 , joint axis _q4 , joint axis _q5 , joint axis _q6 , link l3, link _l5 , link _l6 , and link _{l7 .} The operation of each parallel link mechanism is well known in the art.

Link _l14 is a support link that supports an end effector l _ee (not shown in Figs. 8 and 9) such as a surgical tool at its distal end. The end effector l _ee supported by link _l14 extends in the direction in which the surgical tool is inserted into the body (or into the eye). Link _l13 is an opposing link that faces link _l14 and moves in parallel with link _l14 when the end effector l _ee is moved in the direction in which the surgical tool is inserted.

Joint axis _q7 is provided between joint axis _q1 and joint axis _q2 , and joint axis _q9 is provided between joint axis _q5 and joint axis _q6 . Link _l9 , joint axis _q15 , and link _l10 are connected between joint axis _q7 and joint axis q9 in this order. As can be seen from Figures 8 and ₉ , these components are made by bonding plate-like members together to form a V-shape, and do not interfere with the operation of parallel link mechanism _pl1 and parallel link mechanism _pl2 .

The linear motion of linear axis _q21 , which is the active axis, is transmitted via link _l12 , joint axis _q18 , link _l11 , and joint axis _q17 , and can rotate link _l4 around joint axis _q1 . When parallel link mechanism _pl1 located on the base side is operated by the rotation of link _l4 , parallel link mechanism pl3 located between parallel link mechanisms _pl1 and _pl2 and parallel link mechanism _pl2 located on the distal end side operate in conjunction with each other, and _{the end effector lee can} be pivoted or moved in the insertion direction with the remote motion center RCM as a fixed point.

The linear motion of linear axis _q20 , which is an active axis, is transmitted via link _l8 , joint axis _q16 , link _l7 , joint axis _q15 , and joint axis _q15 , and can rotate link _l9 around joint axis _q7 . Here, linear axis _q19 , which is a passive axis, is inserted between link _l16 and link _l17 , and connects joint axes _q10 and _q11 . While link _l9 rotates around joint axis _q7 due to the motion of each linear axis _q20 , linear axis _q19 keeps link _l15 and link _l16 (and link _l17 ) on a straight line, and connects joint axes _q10 and _q11 at both ends of these links in a freely expandable and contractible manner. When linear axis _q19 is displaced due to the linear motion of linear axis _q20 , link _l15 in the parallel link mechanism _pl2 located at the distal end moves in the extension direction, and therefore the end effector _lee supported by link _l14 moves in the insertion direction.

In short, the linear axis _q19 is connected between the joint axis _q10 and the joint axis _q11 via the link _l16 and the link _l17 so as to linearly move the end effector _lee in the insertion direction according to the amount of displacement. In the implementation example of the origami structure, the linear axis _q19 is configured to deform in the surface direction of the YZ plane perpendicular to the XZ plane. As shown in the lower left of Figure 8 and Figure 9, the linear axis _q19 is composed of a link mechanism in which the link _l16 and the link _l17 deform so as to have a V-shape on the YZ plane.

The joint link configuration of the linear axis _q19 consisting of a V-shaped link mechanism is shown in the lower right of Fig. 8. The linear axis _q19 is a passive axis, but while the end effector l _ee is translated and rotated by the operation of the linear axis _q20 and the linear axis _q21 , it has the role of keeping the link _l15 and the link _l16 (and the link _l17 ) on a straight line and of connecting the joint axes _q10 and _q11 at both ends of these links in a freely expandable and contractible manner.

8, the linear axis _q19 is configured by connecting a parallel link mechanism pl81 consisting of joint axis _q22 , joint axis _q23 , joint axis _q24 , joint axis _q25 , link _l18 , link _l19 , link _l20 , and link _l21 , and a parallel link mechanism _pl82 consisting of joint axis _q23 , joint axis _q24 , joint axis _q26 , joint axis _q27 , link _l18 , link _l19 , link _l20 , and link _l21 , via link _l20 . Therefore, the linear axis _q19 has a V-shape in which _{the parallel link mechanism pl81 and} the parallel link mechanism _pl82 overlap, with the link _l20 as the valley. When the parallel link mechanism pl ₈₁ and the parallel link mechanism pl ₈₂ are folded, the link l ₂₀ is displaced in the surface direction of the YZ plane, which becomes the displacement amount of the linear motion axis q _19. In addition, the link l ₁₈ is connected to the link l ₁₆ , and the link l ₂₃ is connected to the link l ₁₇ .

C-2. Coupling structure applied to robot arm As described in C-1 above, the two linear axes _q20 and _q21 can each be configured as a linear slider on the driven shaft side in the coupling device according to the present disclosure, and can be linearly operated by connecting to a linear actuator on the driving shaft side installed outside the robot arm 700 (specifically, on the robot device main body side on which the robot arm 700 is mounted). In this C-2, the specific configuration of the linear axes _q20 and _q21 and the coupling with the driving shaft side will be described in detail.

Fig. 10 shows an external configuration (perspective view) of a drive unit 1000 on the drive shaft side that operates each of linear motion shafts _q20 and _q21 disposed near the bottom of the robot arm 700. Fig. 11 shows a schematic diagram of a joint link configuration of the drive unit 1000.

As shown in FIG. 11, the drive unit 1000 includes a linear actuator 1010 for driving one linear axis q ₂₀ and a linear actuator 1020 for driving the other linear axis q ₂₁ .

One linear actuator 1010 includes a stator 1011, a rotor 1012, and a motor q _A,1 . The stator 1011 has a guide rail (not shown in FIG. 11) that guides and supports the rotor 1012, and is fixed to a mechanical ground. The rotor 1012 is placed on the stator 1011, and reciprocates in the longitudinal direction of the stator 1011 along the guide rail by power from the motor q _A,1 . The motor q _A,1 may be either a rotary motor or a linear motor as long as it can be converted into power in the longitudinal direction of the stator 1011.

Similarly, the other linear actuator 1020 includes a stator 1021, a rotor 1022, and a motor q _A,2 , and is configured so that the rotor 1022 reciprocates in the longitudinal direction of the stator 1011 by power from the motor q _A,1 .

10, the linear actuator 1010 and the linear actuator 1020 have the stators 1011 and 1021 supported and fixed to the frame 1030 so that their longitudinal directions (i.e., the linear directions of the rotors 1012 and 1022) coincide with the X direction. The frame 1030 is formed by assembling a plurality of sheet metal parts by screw fastening, for example, as shown in the figure. The frame 1030 also has openings 1031 and 1032 for exposing the upper surfaces of the rotors 1012 and 1022, respectively, over the range of movement in the X direction when the rotors 1012 and 1022 reciprocate in the X direction. The upper surface _C'1 of the rotor 1012 and the upper surface _C'2 of the rotor 1022 are coupling surfaces that couple with the rotors of the linear sliders on the driven shaft side. Therefore, the corresponding rotors on the driving shaft side and the driven shaft side can be coupled to each other through these openings 1031 and 1032.

Next, a method for connecting the robot arm 700 and the drive unit 1000 will be described. The principle of the coupling device disclosed herein is applied to the connection between the robot arm 700 and the drive unit 1000.

12 shows a bottom view of the robot arm 700 on the driven shaft side. The linear motion axis _q20 and the linear motion axis _q21 are respectively configured using a linear slider 1210 and a linear slider 1220. As already described with reference to FIG. 22, the linear slider 1210 and the linear slider 1220 are respectively composed of a stator and a rotor, the stator has a guide rail for guiding and supporting the rotor, and the rotor is placed on the stator and can reciprocate along the guide rail in the longitudinal direction of the stator. Here, the stators of the linear sliders 1210 and the linear sliders 1220 of the linear motion axis _q20 and the linear motion axis _q21 are supported and fixed to the link _l1 of the robot arm 700 so that the longitudinal direction (i.e., the rectilinear direction of the rotor) coincides with the X direction. The longitudinal movement of the rotor on one linear slider 1210 side is the motion of the linear axis q ₂₀ , and the longitudinal movement of the rotor on the other linear slider 1220 side is the motion of the linear axis q ₂₁ .

Link _l1 is made of a flat part made of sheet metal or the like, and has openings 1231 and 1232 for exposing the upper surfaces of the rotors of linear slider 1210 and linear slider 1220 over the range of motion when the rotors reciprocate in the X direction. The upper surfaces _C1 and _C2 of each rotor are connecting surfaces for connecting with the upper surface _C'1 of rotor 1012 of linear actuator 1010 on the drive shaft side and the upper surface _C'2 of rotor 1022 of linear actuator 1020, respectively.

13 shows a top view of the drive unit 1000 on the drive shaft side. As already described with reference to FIG. 10, the frame portion 1030 has openings 1031 and 1032 for exposing the top surfaces of the rotors 1012 and 1022 over the range of motion when the rotors 1012 and 1022 reciprocate in the X direction. The top surface _C'1 of the rotor 1012 and the top surface _C'2 of the rotor 1022 are coupling surfaces that couple with the rotors of the linear sliders on the driven shaft side.

As can be seen from Figures 12 and 13, the corresponding rotors on the driving shaft side and the driven shaft side can be brought into contact with each other via openings 1231 and 1232 provided in link _l1 on the robot arm 700 side and openings 1031 and 1032 provided in frame portion 1030 on the drive unit 1000 side.

The robot arm 700 and the drive unit 1000 are connected using the attraction force of a magnet.

On the robot arm 700 side, magnets 1251 and 1252 are arranged on the upper surface _C1 of the rotor of the linear slider 1210, and magnets 1253 and 1254 are arranged on the upper surface _C2 of the rotor of the linear slider 1220. In addition, four magnets 1255 to 1258 are arranged on the link _l1 that supports and fixes the stators of the linear slider 1210 and the linear slider 1220.

On the other hand, on the drive unit 1000 side, magnets 1351 and 1352 are arranged on the upper surface _C'1 of the rotor 1012 of the linear actuator 1010, and magnets 1353 and 1354 are arranged on the upper surface _C'2 of the rotor 1022 of the linear actuator 1020. Four magnets 1355 to 1358 are arranged on the upper surface of the frame part 1030 that supports and fixes the stator 1011 of the linear actuator 1010 and the stator 1021 of the linear actuator 1020. The positions of these magnets 1355 to 1358 correspond to the positions of the four magnets 1255 to 1258 arranged in the link _l1 on the robot arm 700 side.

The polarity of each magnet is set so that an attractive force is generated between opposing magnets 1251 and 1351, between magnets 1252 and 1352, between magnets 1253 and 1353, between magnets 1254 and 1354, between magnets 1255 and 1355, between magnets 1256 and 1356, between magnets 1257 and 1357, and between magnets 1258 and 1358. In the example shown in Figures 12 and 13, magnets 1251 to 1258 arranged on the robot arm 700 side are all set to S poles, and magnets 1351 to 1358 arranged on the drive unit 1000 are all set to N poles. However, the polarity combinations are not limited to these, and other polarity combinations may be used as long as an attractive force acts between opposing magnets. Additionally, magnets 1251-1258 and magnets 1351-1358 can be fixed by adhesion, and the use of heat-resistant magnets makes it possible to use a thermosetting adhesive (ibid.).

Therefore, as shown in Figures 14 to 16, by simply placing the robot arm 700 on the drive unit 1000, the two can be connected by the mutual attraction of the corresponding magnets. As already explained with reference to Figure 4, the alignment at this time is only the orientation of one axis of rotation in the longitudinal direction (i.e., the X direction) of the linear slider and the slider of the linear actuator, and this alignment is achieved by the attraction of the magnets.

In addition, when the robot arm 700 and the drive unit 1000 are connected with their longitudinal orientations aligned, the positions of the corresponding rotors on the linear slider and linear actuator may not match, resulting in the rotors not being connected to each other. In such a case, for example, by moving the rotor on the linear actuator side in the longitudinal direction (X direction) using a return-to-origin operation, when the rotor's position matches that of the corresponding rotor on the linear slider side, the magnetic attraction will connect the rotors to each other (see FIG. 5, for example).

The alignment required when connecting the robot arm 700 and the drive unit 1000 is only the orientation of one axis of rotation in the longitudinal direction. This alignment can be made even easier by using a positioning pin. In the example shown in Figures 12 and 13, the positioning pins 1341 and 1342 are attached to the frame part 1030 of the drive unit 1000, which is the drive shaft side, while the link _l1 , which is the bottom surface of the robot arm 700, which is the driven shaft side, has pin holes 1241 and 1242 drilled at locations facing the positioning pins 1341 and 1342. Therefore, by connecting the linear slider 110 and the linear actuator 120 so that the positioning pins 1341 and 1342 are fitted into the pin holes 1241 and 1242, respectively, the alignment between the stators 112 and 122 can be easily achieved.

C-3. Features The features of the robot arm 700 according to the implementation example of the present disclosure introduced in this section C will be summarized.

The adoption of a coupling structure that utilizes the magnetic attraction and positioning pins makes it easy to perform alignment work when attaching the robot arm 700 to the drive unit 1000. In addition, the robot arm 700 can be removed from the drive unit 1000 simply by pulling it against the magnetic attraction, reducing the workload of attachment and detachment and making it easy to replace the robot arm 700. Therefore, non-engineers such as surgeons and assistants can replace the robot arm 700 during work, achieving a coupling with high reproducibility.

The robot arm 700 and the drive unit 1000 are configured to use magnetic attraction and friction for coupling and thrust transmission between them. Therefore, it is possible to transmit the power generated by the actuators q _A,1 and q _A,2 on the drive unit 1000 side to the linear axis q ₂₀ and linear axis q ₂₁ on the robot arm 700 side without backlash, and as a result, the end effector (surgical tool) l _ee at the distal end of the robot arm 700 can be operated with high accuracy.

As can be seen from FIG. 12, the structure of the connection portion of the robot arm 700 with the drive unit 1000 is simplified. This simplifies the manufacturing process, leading to lower costs. In addition, the robot arm 700 has a simple structure overall that is not complicated, including the connection portion with the drive unit 1000, which allows gas to easily penetrate during sterilization, facilitating the sterilization process.

D. Modifications of the Coupling Device The basic configuration of the coupling device according to the present disclosure was described above in Section B. In this Section D, modifications (or improvements) of the coupling device will be described.

FIG. 17 shows the configuration of a modified coupling device 1700. The coupling device 1700 is configured by arranging a linear slider 1710 on the driven shaft side and a linear actuator 1720 on the driving shaft side facing each other.

The linear slider 1710 includes a rotor 1711 and a stator 1712 that guides and supports the rotor 1711 in the longitudinal direction. On the other hand, the linear actuator 1720 includes a rotor 1721 and a stator 1722 that guides and supports the rotor 1721 in the longitudinal direction, and the rotor 1721 moves linearly in the longitudinal direction of the stator 1722 by power obtained from a motor (not shown).

The surface joining of the linear slider 1710 and the linear actuator 1720 utilizes the attractive force of magnets. On the linear slider 1710 side, magnets 1713 and 1714 are arranged at both ends of the longitudinal direction of the stator 1712, and magnet 1715 is arranged on the top surface of the rotor 1711. On the linear actuator 1720 side, magnets 1723 and 1724 are arranged at both ends of the longitudinal direction of the stator 1722, and magnet 1725 is arranged on the top surface of the rotor 1721. The polarity of each magnet is set so that an attractive force is generated between the opposing magnets 1713 and 1723, between magnets 1714 and 1724, and between magnets 1715 and 1725.

Due to precision errors in machining, for example, on the linear slider 1710 side, there may be a discrepancy between the height of magnets 1713 and 1714 arranged on stator 1712 and the height of magnet 1715 arranged on rotor 1711. Components such as rotor 1711 and stator 1712 are expected to be manufactured by cutting, and machining errors are difficult to ignore. Similarly, on the linear actuator 1720 side, there may be a discrepancy between the height of magnets 1713 and 1714 arranged on stator 1712 and the height of magnet 1715 arranged on rotor 1711.

If the rotor 1711 on the driven shaft side and the rotor 1721 on the driving shaft side are not in close contact with each other due to a difference in height between the magnets, the magnetic attraction force of the magnets will decrease. As a result, when transmitting power from the rotor 1721 on the driving shaft side to the rotor 1711 on the driven shaft side, the friction force in the thrust direction will be weakened, resulting in a problem of reduced transmission efficiency.

Therefore, in the modified example shown in FIG. 17, the magnets are attached via a means for compensating for the height discrepancy. Specifically, magnets 1713 and 1714 are attached to stator 1712 via springs 1731 and 1732, respectively. When magnets 1713 and 1714 attached to stator 1712 are higher than magnet 1715 attached to rotor 1711, springs 1731 and 1732 contract to lower the heights of magnets 1713 and 1714, thereby compensating for the height discrepancy. As a result, rotor 1711 on the driven shaft side and rotor 1721 on the driving shaft side are in sufficient contact with each other, preventing a decrease in the magnetic attraction force and a decrease in the efficiency of power transmission from rotor 1721 on the driving shaft side to rotor 1711 on the driven shaft side.

Figure 18 shows another modified example configured to attach a magnet via a means for compensating for height discrepancy. In coupling device 1800 relating to the modified example shown in Figure 18, rotor 1711 having magnet 1715 attached thereto is attached to stator 1712 via base 1803 supported by springs 1801 and 1802. Stator 1712 is provided with a recess in which base 1803 can move in the height direction, and base 1803 is attached to the recess via springs 1801 and 1802. Springs 1801 and 1802 are preferably the same part. Springs 1801 and 1802 apply a preload in the height direction to rotor 1711 (and magnet 1715). Therefore, the height difference is compensated for so that the magnet 1715 attached to the rotor 1711 is not lower than the magnets 1713 and 1714 attached to the stator 1712. As a result, the rotor 1711 on the driven shaft side and the rotor 1721 on the driving shaft side are in sufficient contact with each other, preventing a decrease in the magnetic attraction force and a decrease in the efficiency of power transmission from the rotor 1721 on the driving shaft side to the rotor 1711 on the driven shaft side.

FIG. 19 shows yet another modified example in which the magnet is attached via a means for compensating for the height discrepancy. In the coupling device 1900 according to the modified example shown in FIG. 19, the rotor 1711 to which the magnet 1715 is attached is attached to the stator 1712 via an air gap 1901. The stator 1712 has a recess that allows the base 1902 to move in the height direction. The base 1902 supports the rotor 1711 and is attached to the stator 1712 via the air gap 1901. The air gap 1901 applies a preload in the height direction to the rotor 1711 (and the magnet 1715). Thus, the height discrepancy is compensated for so that the magnet 1715 attached to the rotor 1711 is not lower than the magnets 1713 and 1714 attached to the stator 1712. As a result, the rotor 1711 on the driven shaft side and the rotor 1721 on the driving shaft side are in close contact with each other, preventing a decrease in the magnetic attraction force and a decrease in the efficiency of power transmission from the rotor 1721 on the driving shaft side to the rotor 1711 on the driven shaft side.

In addition to springs and air gaps, various flexible parts that act as a preload in the height direction of the magnet can be used as a means for compensating for the height discrepancy. In Figs. 17 to 19, a modified example is shown in which the linear slider 1710 is equipped with a means for compensating for the height discrepancy, but the linear actuator 1720 may also be configured to be equipped with a means for compensating for the height discrepancy.

Although not shown in Figures 17 to 19, in all of the modified examples, by combining a positioning pin on the stator on the linear actuator side with a pin hole for fitting on the stator on the linear slider side (see Figure 6, for example), it is possible to easily adjust the orientation of one axis of rotation in the longitudinal direction.

E. Application Example to Medical Robot System In this section E, an application example in which the principle of the coupling device according to the present disclosure is applied to a medical robot system will be described.

E-1. Schematic configuration of a medical robot system Fig. 20 shows a schematic configuration example of a medical robot system 2000 used for surgical operations. The type of surgery referred to here includes laparoscopic surgery, laparoscopic surgery, superficial surgery, ophthalmic (eyeball or fundus) surgery, and the following description will be mainly based on ophthalmic surgery.

The medical robot system 2000 is of a master-slave type and is composed of a master device 2010 that instructs a user such as a surgeon to operate a surgical tool, and a slave device 2020 that drives the surgical tool according to instructions from the master device 2010. The master device 2010 and the slave device 2020 are interconnected via a transmission path 2030 such as an optical fiber.

The master device 2010 is placed outside the operating room or in a location away from the operating table inside the operating room. On the master device 2010 side, surgical field images and the like sent from the slave device 2020 are displayed on the screen of a monitor 2011, and a user such as a surgeon manually operates an operation input device 2012 while observing the surgical field image to remotely instruct the operation of surgical tools. The operation input device 2012 is, for example, a manipulator that can perform operations with three translational degrees of freedom to instruct the translational movement of the surgical tool T, three rotational degrees of freedom to instruct a change in the posture of the surgical tool T, and one degree of freedom of grasping, such as opening and closing forceps.

On the other hand, the slave device 2020 is placed near the operating table and drives surgical tools according to instructions from the master device 2010 to perform surgery on a patient lying on the operating table. The slave device 2020 also transmits images of the surgical field captured by a camera and other sensor information to the master device 2010, which then provides feedback to a user such as a surgeon.

The slave device 2020 includes a first robotic device 2021, a second robotic device 2022, and a microscope 2023. The microscope 2023 observes the surgical field. The field of view of the microscope 2023 may include the eyeball E and the surgical tool T inside the eyeball E. A user such as a surgeon may directly observe the surgical field through the eyepiece of the microscope 2023. Alternatively, an image of the surgical field taken by a camera (not shown) may be transmitted to the master device 2010 via the microscope 2023 and displayed on the screen of the monitor 2011, allowing the user to observe the surgical field from the display screen.

The first robotic device 2021 and the second robotic device 2022 are positioned near the operating table.

The first robot device 2021 supports a surgical tool such as forceps at its distal end. The first robot device 2021 is a robot arm configured by combining multiple parallel link mechanisms, for example as shown in Figures 7 to 9, and can pivot and move the surgical tool T supported at its distal end in the insertion direction with the remote motion center RCM as a fixed point. However, in Figure 20, the structure of the first robot device 2021 is simplified to avoid cluttering the drawing.

On the other hand, the second robot device 2022 is, for example, a serial link robot having three or more degrees of freedom, configured by connecting multiple links in series with joint axes. However, the second robot device 2022 may be a robot device having any configuration other than a serial link. In addition, the second robot device 2022 is assumed to be manually operated by a user such as an operator or an assistant by directly applying force, but of course some of the joint axes may be active joints, and the operation of the active joints may be controlled from the master device 2010. The second robot device 2022 is fixed to a mechanical ground at its base side and supports the first robot 2021 at its distal end. In addition to being directly fixed to the mechanical ground, the second robot device 2022 may be guided and supported by rails (not shown) laid on the mechanical ground so that it can move within the operating room along the rails. The rails may be laid in an arc shape around the patient's head, for example.

The principle of the coupling device according to the present disclosure is applied to connect the first robot device 2021 to the distal end of the second robot device 2022. The first robot device 2021 is the driven shaft side, and the second robot device 2022 is the driving shaft side. The first robot device 2021 realizes the pivot movement and translation movement of the surgical tool T by the power transmitted from the second robot device 2022. The first robot device 2021 is attached to the second robot device 2022 in a detachable and replaceable manner. When it is desired to replace the surgical tool T, the first robot device 2021 is removed from the second robot device 2022, and another first robot device 2021 supporting a new surgical tool T' is attached to the second robot device 2022. The first robot device 2021 may be disposable.

The first robot device 2021 is a robot arm having an origami structure formed by combining multiple parallel links as shown in Figures 7 to 9. The first robot device 2021 supports a surgical tool T at its distal end, and rotors of linear sliders for transmitting power to linear motion shafts _q20 and _q21 , which are respectively involved in the pivot motion and translation motion of the surgical tool T, are arranged on the bottom surface (see, for example, Figure 12).

On the other hand, a drive unit for operating each of the linear axes q and _q of the first robot device 2021, as shown in Figures 10 and ₁₁ , is mounted on the distal end of the second robot device 2022. This drive unit includes linear actuators driven by linear axes q _and q _, respectively, and the rotors of these linear actuators are connected to the rotor (described above) on the bottom surface of the first robot device 2021, making it possible to transmit power to the first robot device 2021.

The linear axis q ₂₀ and the linear axis q ₂₁ on the first robot device 2021 side are driven axes, and the linear axis q _A,1 and the linear axis q _A,2 on the second robot device 2022 side are driving axes. A linear motion system is adopted for these driving axes and driven axes, and the driving axes and driven axes are connected by surface joining using the magnetic attraction force. Therefore, complicated alignment and orientation are not required between the first robot device 2021 and the second robot device 2022. That is, as shown in FIG. 14 to FIG. 16, the connection between the two is realized by a simple operation of placing the first robot device 2021 on the distal end of the second robot device 2022. In addition, after the connection, the magnetic attraction force and friction force can be used to precisely transmit power from the second robot device 2022 to the first robot device 2021 without backlash.

The first robot device 2021 is driven by a linear actuator and is capable of precise manipulation of, for example, about 10 microns, and can be called a "fine-motion robot." In contrast, the second robot device 2022 can also be called a "coarse-motion robot" since it is manually operated. During surgery, the second robot device 2022 can be draped to effectively separate clean and non-clean areas.

When starting surgery, first, a user such as a surgeon manually moves the second robot device 2022 so as to insert the surgical tool T into the eyeball E. At that time, a trocar (not shown) is inserted at the insertion position of the surgical tool T into the eyeball E. Next, the user instructs the second robot device 2022 to move so as to align the remote motion center RCM of the surgical tool T with the insertion position. When the insertion position of the surgical tool T and the remote motion center RCM are in the same position, the load applied to the insertion position when the surgical tool T is pivoted and translated is reduced, thereby achieving minimally invasive surgery.

The first robot device 2021 can be remotely controlled from the master device 2010. A user such as a surgeon can instruct the pivot and translational movements of the surgical tool T by manually operating the operation input device 2012. In addition, sensor information such as external forces applied to the surgical tool T is fed back to the master device 2021. Bilateral control is performed by utilizing two-way communication between the master device 2010 and the slave device 2020 so that the displacement and force correspond between the master device 2010 and the slave device 2020.

Motion scaling may be used so that the physical displacement amount with which the user manually operates the operation input device 2012 matches the physical displacement amount of the surgical tool T. This enables fine remote operation from the master device 2010, making remote surgery easier. Note that the user who manually operates the operation input device 2012 and the user who manually operates the second robotic device 2022 may be the same or different. For example, the user who manually operates the operation input device 2012 may be the surgeon, and the user who manually operates the second robotic device 2022 may be an assistant.

If it becomes necessary to use another surgical tool T' during surgery, the currently inserted surgical tool T is removed from the eyeball E, the first robotic device 2021 and the second robotic device 2022 are withdrawn from the affected area, and the first robotic device 2021 is removed from the second robotic device 2022 in a safe location. Since the first robotic device 2021 and the second robotic device 2022 are only connected by the magnetic attraction force, this removal operation can be performed simply by lifting the first robotic device 2021. Thereafter, the surgical tool replacement is completed by simply placing the other first robotic device 2021 supporting the other surgical tool T' on the distal end of the second robotic device 2022, as described above (i.e., the case shown in Figures 14 to 16). Also, as described above, the clean area and the non-clean area can be effectively separated. Then, the user such as the surgeon can resume the surgery using a new surgical tool T'.

E-2. Functional Configuration of Medical Robot System In this section E-2, the functional configuration of the medical robot system 2000 described in section E-1 above will be described.

FIG. 21 shows an example of the functional configuration of a medical robot system 2000. As described above, the medical robot system 2000 is of a master-slave type and is composed of a master device 2010, which is used by a user such as a surgeon to instruct the operation of a surgical tool, and a slave device 2020, which drives the surgical tool according to instructions from the master device 2010, and the master device 2010 and the slave device 2020 are capable of bidirectional communication via a transmission path 2030. Bilateral control is performed between the master device 2010 and the slave device 2020, using bidirectional communication to correspond to the amount of displacement and the force.

The master device 2010 includes a master-side control unit 2111, an input unit 2112, a presentation unit 2113, and a master-side communication unit 2114. The master device 2010 operates under the overall control of the master-side control unit 2111.

The input unit 2112 includes the operation input device 2012 in FIG. 20, and is used by a user such as a surgeon to remotely operate the surgical tool T on the slave device 2020 side. The operation input device 2012 is, for example, a manipulator that can perform operations with three translational degrees of freedom for instructing translational movement of the surgical tool T, three rotational degrees of freedom for instructing a change in the posture of the surgical tool T, and one degree of freedom for grasping, such as opening and closing the forceps (when the surgical tool T is forceps). The input unit 2112 may further include an input device other than the operation input device 2012. For example, the input unit 2112 may further include a joystick, a foot switch, or another input device for performing 3D operations on the screen.

The presentation unit 2113 presents to the user information related to the surgery being performed in the slave device 2020, mainly based on sensor information acquired by a sensor unit 2123 (described later) on the slave device 2020 side. The presentation unit 2113 includes the monitor 2011 in FIG. 20. When an operative field image captured using a microscope 2023 is sent from the slave device 2020 with low latency, the presentation unit 2113 displays the operative field image in real time on the screen of the monitor 2011.

The presentation unit 2113 may have a force feedback function that is incorporated and implemented in the operation input device 2012. The force feedback function is realized, for example, by driving at least some of the axes of a manipulator (described above) having three translational degrees of freedom, a rotational degree of freedom, and a grasping degree of freedom with a motor. When the sensor unit 2123 on the slave device 2020 side is equipped with a function for measuring forces such as external forces and moments acting on the surgical tool T, and force feedback information is sent from the slave device 2020 with low latency, the presentation unit 2113 provides force feedback to the user in real time by driving the motor of the manipulator.

The master-side communication unit 2114 performs signal transmission and reception processing with the slave device 2020 via the transmission path 2030 under the control of the master-side control unit 2111. For example, if the transmission path 2030 is made of optical fiber, the master-side communication unit 2114 includes an electrical-to-optical conversion unit that converts an electrical signal sent from the master device 2010 into an optical signal, and an optical-to-electrical conversion unit that converts an optical signal received from the transmission path 2030 into an electrical signal. The master-side communication unit 2114 transfers operation commands for the surgical robot 2122 input by the user (surgeon) via the operation input device 2012 to the slave device 2020 via the transmission path 2030. The master-side communication unit 2114 also receives sensor information sent from the slave device 2020 via the transmission path 2030.

On the other hand, the slave device 2020 includes a slave-side control unit 2121, a surgical robot 2122, a sensor unit 2123, and a slave-side communication unit 2124. The slave device 2020 performs operations according to instructions from the master device 2010 under the overall control of the slave-side control unit 2121.

The surgical robot 2122 includes a first robot device 2021 and a second robot device 2022 in FIG. 20. The second robot device 2022 is connected to the first robot device 2021 at its tip, and the first robot device 2021 supports a surgical tool T at its distal end. As described above, the principle of the coupling device disclosed herein is applied to the connection between the first robot device 2021 and the second robot device 2022. The slave side control unit 2121 interprets the operation command sent from the master device 2010 via the transmission path 2030, converts it into a drive signal for a drive shaft for pivoting and translating the surgical tool T, and outputs it to linearly move the drive shaft on the second robot device 2022 side. Then, when power is transmitted to the driven shaft on the first robot device 2021 side without backlash due to the magnetic attraction force and friction force, the surgical tool at the distal end pivots and translates via the parallel link mechanism.

The sensor unit 2123 is equipped with multiple sensors that detect the status of the surgical robot 2122 itself and the status of the affected area during surgery, and is further equipped with an interface for acquiring sensor information from various sensor devices installed in the operating room. For example, the sensor unit 2123 is equipped with a force torque sensor (FTS) for measuring the external force and moment acting on the surgical tool T during surgery. The sensor unit 2123 is also equipped with an interface for acquiring an observation image of the affected area obtained by the microscope 2023.

The slave-side communication unit 2124 performs transmission and reception processing with the master device 2010 via the transmission path 2030 under the control of the slave-side control unit 2121. For example, if the transmission path 2030 is made of optical fiber, the slave-side communication unit 2124 includes an electrical-to-optical conversion unit that converts an electrical signal sent from the slave device 2020 into an optical signal, and an optical-to-electrical conversion unit that converts an optical signal received from the transmission path 2030 into an electrical signal.

The slave-side communication unit 2124 transfers the force data of the surgical tools acquired by the sensor unit 2123 and the surgical field image observed by the microscope 2023 to the master device 2010 via the transmission path 2030. The slave-side communication unit 2124 also receives operation commands for the surgical robot 2122 sent from the master device 2010 via the transmission path 2030.

E-3. Features The features of the medical robot system 2000 according to the application example of the present disclosure introduced in this section E will be summarized below.

A coupling structure that utilizes the magnetic attraction and positioning pins is used to connect the first robot device 2021, which is the driven shaft side, and the second robot device 2022, which is the driving shaft side, making alignment work easy when attaching them. In addition, the first robot device 2021 can be removed from the second robot device 2022 simply by pulling against the magnetic attraction, reducing the workload of attachment and detachment, and the surgical tool T can be easily replaced as a unit with the first robot device 2021. Therefore, non-engineers such as surgeons and assistants can replace the surgical tool T during surgery, achieving a coupling with high reproducibility.

The first robot device 2021, which is the driven shaft side, and the second robot device 2022, which is the driving shaft side, are connected and thrust is transmitted using magnetic attraction and friction. Therefore, power can be transmitted without backlash, and the surgical tool T at the distal end of the first robot device 2021 can be operated with high precision.

As shown in FIG. 12, the first robot device 2021 is made of a robot arm with a simplified structure at the connecting portion. This simplifies the manufacturing process, leading to reduced costs. In addition, the first robot device 2021 has a simple structure overall that is not complicated, including the connecting portion with the second robot device 2022, which allows easy penetration during gas sterilization and facilitates the sterilization process.

In section B above, it was explained that with the coupling device of the present disclosure, when a load in the opposite direction to the thrust transmitted from the drive shaft is applied to the driven shaft, and there is a relationship of "thrust ≧ load" in the thrust direction, power can be transmitted from the drive shaft to the driven shaft without backlash. When the medical robot system 2000 is applied to ophthalmic surgery, it is assumed that the load applied from the affected area (such as the fundus) to the surgical tool T, i.e., the driven shaft, is small, and the relationship of "thrust ≧ load" is established, so power can be transmitted precisely. Therefore, with the medical robot system 2000, precise and minimally invasive surgery can be realized.

The present disclosure has been described in detail above with reference to specific embodiments. However, the present disclosure should not be interpreted as being limited to the above-described embodiments, and it is self-evident that a person skilled in the art can modify or substitute the embodiments without departing from the gist of the present disclosure. Furthermore, the effects described in this specification are merely examples, and the effects brought about by the present disclosure are not limited, and there may be additional effects not described in this specification.

　Although the present specification has mainly described an embodiment in which the present disclosure is applied to a coupling device used in the medical field (such as a medical manipulator system), the gist of the present disclosure is not limited to this. For example, the coupling device according to the present disclosure can also be applied to a robot or manipulator system that performs various difficult or dangerous tasks in human industrial or production activities, such as maintenance work in nuclear power plants, thermal power plants, and petrochemical plants, transporting and assembling parts in manufacturing plants, cleaning in high-rise buildings, and rescue at fire scenes and other locations.

In short, this disclosure has been described in the form of examples, and the contents of this specification should not be interpreted in a restrictive manner. The claims should be taken into consideration in determining the gist of this disclosure.

In addition, this disclosure can also be configured as follows:

(1) a linear driven shaft portion;
A linear drive shaft portion;
a connecting portion that connects the driven shaft portion and the driving shaft portion by surface joining;
A coupling device comprising:

(2) The driven shaft portion includes a linear slider including a first rotor and a first stator,
the drive shaft includes a linear actuator including a second rotor and a second stator;
the connecting portion connects the first rotor and the second rotor, and the first stator and the second stator by surface joining, respectively, so that the moving directions of the first rotor and the second rotor are aligned with each other.
A coupling device as described in (1) above.

(3) One of the first stator and the second stator has a positioning pin, and the other has a pin hole into which the positioning pin is fitted.
A coupling device as described in (2) above.

(4) The connecting portion connects the first rotor and the second rotor, and connects the first stator and the second stator, by utilizing an attractive force of a magnet.
A coupling device according to any one of (2) or (3) above.

(5) The coupling portion includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft portion, and a plurality of second magnets attached to each of the second rotor and the second stator of the drive shaft portion,
The second magnet is disposed on the second stator at a position corresponding to the first magnet attached to the first stator.
A coupling device as described in (4) above.

(6) The first magnet is attached to at least one of the first rotor and the first stator via a relaxation member that relaxes the height difference, or the second magnet is attached to at least one of the second rotor and the second stator via a relaxation member that relaxes the height difference.
A coupling device as described in (5) above.

(6-1) The buffer member is a spring, an air gap, or other flexible part that applies a preload to the magnet in the height direction.
A coupling device as described in (6) above.

(7) After the first stator and the second stator are connected to each other, the connecting portion connects the first rotor to the second rotor through an operation of moving the second rotor on the second stator.
A coupling device according to any one of (4) to (6) above.

(8) a first robotic device supporting a surgical tool at a distal end;
a second robotic device coupled to the first robotic device;
Equipped with
a linear motion driven shaft portion of the first robot device and a linear motion drive shaft portion of the second robot device are connected by a surface joint;
The first robot device operates the surgical tool by power transmitted from the drive shaft portion to the driven shaft portion.
Medical robotic device.

(9) The first robotic device supports the surgical tool so as to have a remote center of motion.
The medical robot device described in (8) above.

(10) The second robotic device is detachably connected to the first robotic device.
A medical robot device according to any one of (8) or (9) above.

(11) The driven shaft portion includes a linear slider including a first rotor and a first stator,
the drive shaft includes a linear actuator including a second rotor and a second stator;
the first rotor and the second rotor, and the first stator and the second stator are connected by surface contact, respectively, such that the first rotor and the second rotor move in the same direction;
A medical robot device according to any one of (8) to (10) above.

(12) One of the first stator and the second stator has a positioning pin, and the other has a pin hole into which the positioning pin fits.
The medical robot device described in (11) above.

(13) The first rotor and the second rotor are connected to each other, and the first stator and the second stator are connected to each other, respectively, by utilizing an attractive force of a magnet.
The medical robot device according to any one of (11) or (12) above.

(14) The first robot device includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft, and the second robot device includes a plurality of second magnets attached to each of the second rotor and the second stator of the drive shaft,
The second magnet is disposed on the second stator at a position corresponding to the first magnet attached to the first stator.
The medical robot device described in (13) above.

(15) The first robot device attaches the first magnet to at least one of the first rotor and the first stator via a relaxation member that relaxes a height difference, or the second robot device attaches the second magnet to at least one of the second rotor and the second stator via a relaxation member that relaxes a height difference.
A medical robot device as described in (14) above.

(16) After the first stator and the second stator are coupled to each other, the second robot device couples the first rotor to the second rotor by moving the second rotor on the second stator.
The medical robot device according to any one of (13) to (15) above.

(17) A link mechanism part that supports a surgical tool at a distal end;
a linear driving shaft portion detachably connected to the linear driving shaft portion by surface contact;
Equipped with
The linear motion driven shaft drives the link drive unit by power transmitted from the linear motion drive shaft.
Medical robotic device.

(17-1) The link mechanism supports the surgical tool so as to have a remote center of motion.
The medical robot device described in (17) above.

(18) The driven shaft portion includes a linear slider including a first rotor and a first stator,
the drive shaft includes a linear actuator including a second rotor and a second stator;
the first rotor and the second rotor, and the first stator and the second stator are connected by surface contact, respectively, such that the first rotor and the second rotor move in the same direction;
The medical robot device described in (17) above.

(19) The first stator has a pin hole into which a positioning pin provided in the second stator on the drive shaft portion side is fitted.
The medical robot device described in (18) above.

(20) The first rotor and the first stator are respectively connected to the second rotor and the second stator on the drive shaft side by utilizing an attractive force of a magnet.
A medical robot device according to any one of (18) or (19) above.

(20-1) The driving mechanism further includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft portion,
a first magnet attached to the first stator is disposed at a position corresponding to a second magnet attached to the second stator of the drive shaft;
A medical robot device as described in (20) above.

(20-2) The first magnet is attached to at least one of the first rotor and the first stator via a relaxation member that relaxes a height difference.
The medical robot device described in (20-1) above.

100...coupling device, 110...linear slider, 111...rotor 112...slider, 113 to 115...magnet 120...linear actuator, 121...rotor, 122...slider 123 to 125...magnet 601, 602...positioning pin, 611, 612...pin hole 700...robot arm 1000 drive unit, 1010...linear actuator 1011...stator, 1012...rotor 1020...linear actuator, 1021...stator 1022...rotor, 1030...frame portion 1031, 3032...opening 1210, 1220...linear slider, 1231, 1232...opening 1241, 1242...pin hole, 1251 to 1258...magnet 1341, 1342...positioning pins, 1351 to 1358...magnets 1700...coupling device (modified example), 1710...linear slider 1711...rotor, 1712...stator, 1713 to 1715...magnets 1720...linear actuator, 1721...rotor 1722...stator, 1731, 1732...spring 1800...coupling device (modified example), 1801, 1802...spring 1803...base 1900...coupling device (modified example), 1901...air gap 1902...base 2000 medical robot system, 2010...master device 2011...monitor, 2012...operation input device, 2020...slave device 2021...first robot device, 2022...second robot device 2023...microscope, 2030...transmission path 2111: Master side control unit, 2112: Input unit, 2113: Presentation unit, 2114: Master side communication unit, 2121: Slave side control unit, 2122: Surgical robot, 2123: Sensor unit, 2124: Slave side communication unit, 2200: Linear slider, 2201: Stator, 2202: Rotor

Claims (20)

A linear driven shaft portion;
A linear drive shaft portion;
a connecting portion that connects the driven shaft portion and the driving shaft portion by surface joining;
A coupling device comprising: the driven shaft portion includes a linear slider including a first rotor and a first stator;
the drive shaft includes a linear actuator including a second rotor and a second stator;
the connecting portion connects the first rotor and the second rotor, and the first stator and the second stator by surface joining, respectively, so that the moving directions of the first rotor and the second rotor are aligned with each other.
2. The coupling device of claim 1. one of the first stator and the second stator has a positioning pin, and the other has a pin hole into which the positioning pin is fitted;
3. A coupling device according to claim 2. the connecting portion connects the first rotor and the second rotor, and the first stator and the second stator, by utilizing an attractive force of a magnet;
3. A coupling device according to claim 2. the coupling portion includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft portion, and a plurality of second magnets attached to each of the second rotor and the second stator of the drive shaft portion,
The second magnet is disposed on the second stator at a position corresponding to the first magnet attached to the first stator.
5. A coupling device according to claim 4. The first magnet is attached to at least one of the first rotor and the first stator via a relaxation member that relaxes the height difference, or the second magnet is attached to at least one of the second rotor and the second stator via a relaxation member that relaxes the height difference.
6. A coupling device according to claim 5. the coupling unit couples the first rotor to the second rotor through an operation of moving the second rotor on the second stator after the first stator and the second stator are coupled to each other;
5. A coupling device according to claim 4. a first robotic device supporting a surgical tool at a distal end;
a second robotic device coupled to the first robotic device;
Equipped with
a linear motion driven shaft portion of the first robot device and a linear motion drive shaft portion of the second robot device are connected by a surface joint;
The first robot device operates the surgical tool by power transmitted from the drive shaft portion to the driven shaft portion.
Medical robotic device. the first robotic device supports the surgical tool so as to have a remote center of motion;
The medical robotic device according to claim 8. the second robotic device is detachably connected to the first robotic device;
The medical robotic device according to claim 8. the driven shaft portion includes a linear slider including a first rotor and a first stator;
the drive shaft includes a linear actuator including a second rotor and a second stator;
the first rotor and the second rotor, and the first stator and the second stator are connected by surface contact, respectively, such that the first rotor and the second rotor move in the same direction;
The medical robotic device according to claim 8. one of the first stator and the second stator has a positioning pin, and the other has a pin hole into which the positioning pin is fitted;
The medical robotic device of claim 11. The first rotor and the second rotor are connected to each other, and the first stator and the second stator are connected to each other, respectively, by utilizing an attractive force of a magnet.
The medical robotic device of claim 11. the first robotic device includes a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft, and the second robotic device includes a plurality of second magnets attached to each of the second rotor and the second stator of the drive shaft,
The second magnet is disposed on the second stator at a position corresponding to the first magnet attached to the first stator.
The medical robotic device of claim 13. the first robot device attaches the first magnet to at least one of the first rotor and the first stator via a relaxation member that relaxes a height difference, or the second robot device attaches the second magnet to at least one of the second rotor and the second stator via a relaxation member that relaxes a height difference;
The medical robotic device of claim 14. After the first stator and the second stator are coupled, the second robot device couples the first rotor to the second rotor by moving the second rotor on the second stator.
The medical robotic device of claim 13. A link mechanism that supports a surgical tool at a distal end;
a linear driving shaft portion detachably connected to the linear driving shaft portion by surface contact;
Equipped with
The linear motion driven shaft drives the link drive unit by power transmitted from the linear motion drive shaft.
Medical robotic device. the driven shaft portion includes a linear slider including a first rotor and a first stator;
the drive shaft includes a linear actuator including a second rotor and a second stator;
the first rotor and the second rotor, and the first stator and the second stator are connected by surface contact, respectively, such that the first rotor and the second rotor move in the same direction;
The medical robotic device of claim 17. the first stator has a pin hole into which a positioning pin provided in the second stator on the drive shaft portion side is fitted;
20. The medical robotic device of claim 18. The first rotor and the first stator are respectively connected to the second rotor and the second stator on the drive shaft side by utilizing magnetic attraction.
20. The medical robotic device of claim 18.

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