Coupling device and medical robot device

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

[0001] 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 that includes a motor that drives the end effector, and a medical robot device that uses the coupling device.

[0002] Robot technology is now widely used in various industrial fields, including medicine. A robot arm (manipulator) typically includes a driven unit, such as an end effector with one or more degrees of freedom at its distal end, and a driving unit, such as a motor, that drives the end effector. 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 to the driven shaft of the end effector.

[0003] For example, a coupling structure has been proposed for connecting a surgical tool unit equipped with a surgical tool at its tip to a drive unit that drives the surgical tool in a medical manipulator system (see Patent Document 1). In this medical manipulator system, the surgical tool unit and the drive unit are connected via an adapter.

[0004] The coupling structure that connects the driven part and the driving part must meet engineering requirements such as easy attachment and detachment for replacing the end effector, good power transmission efficiency, little backlash, and good reproducibility in connection.When applied to the medical field, an additional medical requirement is that the driven part, which is detached and replaced, must be able to be kept clean.

[0005] Japanese Patent Application Laid-Open No. 2022-27324

[0006] An object of the present disclosure is to provide a coupling device that connects a driven part having an end effector to a driving part including a motor that drives the end effector while satisfying engineering requirements, and a medical robotic device that utilizes the coupling device.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and a first aspect thereof is a coupling device including: a linear-acting driven shaft portion; a linear-acting driving shaft portion; and a connecting portion that connects the driven shaft portion and the driving shaft portion by surface contact.

[0008] The driven shaft includes a linear slider including a first rotor and a first stator, and 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, respectively, by surface contact so that the first rotor and the second rotor move in the same direction.

[0009] The coupling portion couples the first rotor and the second rotor, and the first stator and the second stator, using the attractive force of a magnet. Specifically, the coupling portion includes a plurality of first magnets attached to the first rotor and the first stator of the driven shaft portion, respectively, and a plurality of second magnets attached to the second rotor and the second stator of the drive shaft portion, respectively, 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.

[0010] A second aspect of the present disclosure is a medical robot device comprising: a first robot device that supports a surgical tool at a distal end; and a second robot device that connects to the first robot device, wherein a linear-motion driven shaft portion on the first robot device side and a linear-motion driving shaft portion on the second robot device side are connected by a surface joint, and the first robot device operates the surgical tool by power transmitted from the driving shaft portion to the driven shaft portion.

[0011] The first robotic device supports the surgical tool so as to have a remote center of motion, and the second robotic device is detachably coupled to the first robotic device.

[0012] A third aspect of the present disclosure is a medical robot device comprising: a link mechanism that supports a surgical tool at a distal end; and a linear motion driven shaft that is detachably connected to a linear motion driving shaft by a surface joint, wherein the linear motion driven shaft drives the link driving section by power transmitted from the linear motion driving shaft.

[0013] According to the present disclosure, it is possible to provide a coupling device and a medical robot device that connect a driven part and a driving part while satisfying engineering requirements and further medical requirements.

[0014] It should be noted that the effects described in this specification are merely examples, and the effects brought about by the present disclosure are not limited to these. Furthermore, the present disclosure may also bring about additional effects in addition to the effects described above.

[0015] Further objects, features, and advantages of the present disclosure will become apparent from the following detailed description based on the embodiments and accompanying drawings.

[0016] FIG. 1 is a diagram showing the basic configuration of a coupling device 100 according to the present disclosure (a separated state before the driven shaft and the drive shaft are coupled). FIG. 2 is a diagram showing the basic configuration of a coupling device 100 according to the present disclosure (a state in which the driven shaft and the drive shaft are coupled). FIG. 3 is a diagram showing the basic configuration of a coupling device 100 according to the present disclosure (a state in which a thrust and a load are applied). FIG. 4 is a diagram for explaining the alignment required for coupling in the coupling device 100. FIG. 5 is a diagram for explaining a method for automatically coupling rotors in the coupling device 100. FIG. 6 is a diagram showing a modified example of the coupling device 100 including a positioning pin. FIG. 7 is a diagram showing the joint link configuration of a robot 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 viewed from the side. 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 a drive unit 1000. 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 diagram showing the top surface of the drive unit 1000. FIG. 14 is a diagram showing the process of connecting the robot arm 700 to the drive unit 1000. FIG. 15 is a diagram showing the process of connecting the robot arm 700 to the drive unit 1000. FIG. 16 is a diagram showing the process of connecting the robot arm 700 to the drive unit 1000. FIG. 17 is a diagram showing a modified example of the coupling device (an example that compensates for height discrepancies). FIG. 18 is a diagram showing another modified example of the coupling device. FIG. 19 is a diagram showing yet another modified example of the coupling device. FIG. 20 is a diagram showing an example of the schematic configuration of a medical robot system 2000. FIG. 21 is a diagram showing an example of the functional configuration of the medical robot system 2000. FIG. 22 is a diagram showing a general configuration of a linear slider 2200.

[0017] Hereinafter, embodiments of the present disclosure will be described in the following order with reference to the drawings.

[0018] A. Overview B. Basic configuration C. Implementation examples C-1. Configuration of robot arm C-2. Coupling structure applied to robot arm C-3. Features D. Modified examples of coupling device E. Application examples to medical robot system E-1. Schematic configuration of medical robot system E-2. Functional configuration of medical robot system E-3. Features

[0019] A. Overview In the mechatronics field, power transmission 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 drive shaft is required to meet engineering requirements such as easy attachment and detachment to allow for easy replacement of end effectors even during operation, good power transmission efficiency, little backlash, and the ability to connect with good reproducibility. Furthermore, in the medical field, in addition to engineering requirements, the coupling structure is also required to ensure the cleanliness of the driven part, which is detached and replaced, as a medical requirement.

[0020] When applied to the medical field, the driven shaft side, which is equipped with a surgical tool as an end effector, is located 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, 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.

[0021] Furthermore, because general surgical procedures require the use of multiple surgical tools, smooth tool exchange is essential. Therefore, a coupling structure that allows for easy attachment and detachment of the driven shaft and drive shaft and high reproducibility is required. For example, in a coupling structure that uses screws to attach the driven shaft to the drive shaft, it is difficult for non-engineers, such as surgeons or assistants, to precisely tighten the screws, and it also makes it difficult to smoothly exchange surgical tools during surgery.

[0022] In a coupling structure in which both the drive shaft and the driven shaft are rotational, the rotational force of the drive shaft generated by a rotary motor is transmitted to the driven shaft via the coupling structure. In this case, the drive shaft and the driven shaft must be coaxially coupled. Therefore, 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 must be performed, making it difficult to ensure precision. Furthermore, in the case of a rotational coupling, backlash occurs due to the use of a reducer on at least one of the drive shaft and the driven shaft, making it difficult to transmit power without backlash. While low-backlash couplers are known in the industry, their complex structure raises concerns about increased costs and the risk of failure due to the increased number of parts. Furthermore, the intricate and complex structure of such couplers makes them difficult to sterilize (e.g., gas penetration during gas sterilization is difficult, resulting in insufficient sterilization).

[0023] In view of the above-mentioned problems, the present disclosure proposes a coupling device that can precisely couple a drive shaft and a driven shaft, which can also be applied to the medical field (such as a medical robot system). The coupling device according to the present disclosure employs a linear motion system for both the drive shaft and the driven shaft, and adopts a configuration in which the drive shaft and the driven shaft are coupled by a surface joint.

[0024] Both the driving shaft and the driven shaft use linear sliders to achieve linear motion. Linear sliders themselves are mechanical components well known in the art. FIG. 22 schematically shows the general configuration of a linear slider 2200. The illustrated linear slider 2200 comprises a stator 2201 and a rotor 2202. The stator 2201 is fixed to, for example, a mechanical ground and has guide rails (details not shown in FIG. 22) that guide and support the rotor 2202. The rotor 2202 is mounted on the stator 2201 and moves back and forth in the longitudinal direction of the stator 2201 along the guide rails. When the linear slider 2200 is on the driving shaft side, it further includes 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 by power transmitted from the outside (drive shaft side). Note that in this specification, in linear sliders and linear actuators, the member that moves (linearly or rotatingly) relative to the stator is called the "rotor."

[0025] The coupling device according to the present disclosure is configured by arranging a linear actuator on the drive shaft side and a linear slider on the driven shaft side facing each other so that their longitudinal directions (i.e., the directions of movement of the rotors) are aligned, and connecting them by surface contact. Therefore, when the rotor on the drive shaft side moves back and forth in the longitudinal direction, the rotor on the driven shaft side also moves integrally, thereby achieving power transmission from the drive shaft to the driven shaft.

[0026] B. Basic Configuration Figures 1 and 2 schematically show 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 drive shaft side. Figure 1 shows the linear slider 110 and the linear actuator 120 in a separated state before they are coupled, and Figure 2 shows the linear slider 110 and the linear actuator 120 in a coupled state in which they are coupled by surface contact.

[0027] The linear slider 110 on the driven shaft side includes a rotor 111, which is a movable part, and a stator 112 that guides and supports the rotor 111 in the longitudinal direction. An end effector (not shown in FIG. 1 ), such as a surgical tool, is attached to the linear slider 110.

[0028] 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 which guides and supports the rotor 121 in the longitudinal direction, and a motor (not shown in Figure 1) which is the driving source for operating the rotor 121.

[0029] The coupling device 100 is configured by arranging a linear slider 110 and a linear actuator 120 opposite each other so that their longitudinal directions (i.e., the moving directions of the rotors 111 and 121) coincide with each other, and connecting them to each other by surface contact.

[0030] The surface-to-surface connection between the linear slider 110 and the linear actuator 120 utilizes the attractive force of magnets. As shown in FIG. 1 , on the linear slider 110 side, magnets 113 and 114 are disposed at both ends of the stator 112 in the longitudinal direction, and magnet 115 is disposed on the upper surface of the rotor 111. On the linear actuator 120 side, magnets 123 and 124 are disposed at both ends of the stator 122 in the longitudinal direction, and magnet 125 is disposed on the upper 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 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 while facing each other, the attractive force between the corresponding magnets realizes connection between the linear slider 110 and the linear actuator 120, i.e., a surface-to-surface connection between the driven shaft and the driving shaft, as shown in FIG. 2 .

[0031] One method for fixing the magnets to the rotor and stator components is by gluing. 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.

[0032] In a coupled state in which the rotor 111 on the driven shaft side and the rotor 121 on the driving shaft side are shown in Figure 2, when the rotor 121 is driven, a frictional force corresponding to the attractive 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 attractive force between the magnets 115 and 125 is F and the coefficient of friction is μ, the frictional force N generated in the thrust direction is N = μF. As shown in Figure 3, if a load is applied to the rotor 111 in the opposite direction to the thrust direction of the rotor 121, when the relationship "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.

[0033] Alignment adjustment when coupling a driven shaft and a driving shaft in the coupling device 100 will be described 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 coupled by surface contact using the attractive force of magnets. Fig. 4 shows a side view and a top view of the coupling device 100 when surface contact is made.

[0034] On the linear slider 110 side, magnets 113 and 114 are disposed at both ends of the stator 112 in the longitudinal direction, and a magnet 115 is disposed on the upper surface of the rotor 111. On the linear actuator 120 side, magnets 123 and 124 are disposed at both ends of the stator 122 in the longitudinal direction, and a magnet 125 is disposed on the upper 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 the magnets 114 and 124, and between the magnets 115 and 125.

[0035] When the linear slider 110 and the linear actuator 120 are brought close to each other and opposed to each other, the magnetic attraction between the corresponding magnets connects the linear slider 110 and the linear actuator 120 by surface contact. As shown in the top view of Figure 4, the alignment at this time is only the orientation of one axis of rotation in the longitudinal direction of each of the stator 112 on the linear slider 110 side and the stator 122 on the linear actuator 120 side, and this alignment is achieved by the magnetic attraction.

[0036] In the case of a coupling structure that employs a rotational system, when coupling, it is necessary to perform the orientation of the two rotational axes of the output shaft on the driving part side and the input shaft on the driven part 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 system and connects the driven shaft and driving shaft by surface contact, so only one axis of rotation in the longitudinal direction is required for orientation, which significantly reduces the load of alignment.

[0037] Furthermore, 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, the rotors 111 and 121 may not be connected to each other due to misalignment of their positions, as shown in Fig. 5(a). Even in such a case, as shown in Fig. 5(b), automatic connection of the rotors 111 and 121 can be achieved by moving the rotor 121 on the linear actuator 120 side in the longitudinal direction of the stator 122, for example, by performing a return-to-origin operation. This is because, as shown in Fig. 5(c), when the positions of the rotors 111 and 121 and the other rotor 111 are aligned, the rotors 111 and 121 are connected to each other due to the attraction force of their magnets 115 and 125.

[0038] As described with reference to FIG. 4 , the coupling device 100 according to the present disclosure requires only one axis of alignment during coupling: longitudinal rotation. This alignment can be further facilitated 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, which is the driving shaft side. On the other hand, pin holes 611 and 612 are drilled in the stator 112 of the linear slider 110, which is the driven shaft side, at locations opposite the positioning pins 601 and 602, respectively. 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 upper part of Figure 6 shows the separated state before the linear slider 110 and linear actuator 120 are connected, and the lower part of Figure 6 shows the state in which the linear slider 110 and linear actuator 120 are connected by utilizing the engagement of positioning pins 601 and 602 with pin holes 611 and 612.

[0039] 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 conversely, a positioning pin may be attached to the driven shaft side and a pin hole provided on the drive shaft side. However, in this case, 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.

[0040] The features of the coupling device 100 according to the present disclosure are summarized below.

[0041] (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 through a surface joint. This reduces the degree of freedom required for alignment and orientation between the drive shaft and driven shaft, easing the workload of attachment and detachment. (2) The coupling device 100 utilizes magnetic attraction and friction to couple and transmit thrust between the drive shaft and driven shaft. This enables backlash-free power transmission from the drive shaft to the driven shaft, improving the accuracy of driving the driven shaft. (3) The coupling device 100 does not use mechanical components such as screws to couple the drive shaft and driven shaft. This simplifies the process of replacing the driven shaft equipped with an end effector such as a surgical tool. Furthermore, even non-engineers, such as surgeons and assistants, can achieve highly reproducible couplings. (4) Overall, the coupling device 100 has a simplified structure. This simplifies the manufacturing process and reduces costs. Furthermore, since coupling device 100 has a simple, uncomplicated structure, it is easily permeable during gas sterilization, making the sterilization process easier.

[0042] C. Implementation Example In this section C, an implementation example of a robot arm to which a linear-acting coupling device according to the present disclosure is applied will be described.

[0043] C-1. Robot Arm Configuration Figure 7 shows the joint link configuration of a robot arm 700 to which the present disclosure can be applied. In the figure, joint axes are represented by "q" and links by "l," with serial numbers identifying each joint q and each link l indicated by subscripts in the lower left corner. However, there are two types of joint axes: rotary axes and linear axes.

[0044] The robot arm 700 is assumed to be a medical robot arm applied to a surgical operation such as an ophthalmic operation (or fundus operation). ee The tip of the is a surgical tool T such as forceps, and the linear axis q 20 and linear axis q 21The power given to the end effector is transmitted by the slider link mechanism. ee is given translational and rotational degrees of freedom.

[0045] The robot arm 700 roughly constitutes a parallel link mechanism, and the end effector ee The position where the longitudinal axis of the end effector intersects with the mechanical ground is 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, and the end effector 1, which is a surgical tool, can be moved. ee Since the load applied to the insertion part when the eyeball is moved or when the eye is operated is reduced, minimally invasive surgery can be realized. 20 By moving the end effector in a straight line, ee can be translated in the longitudinal direction (insertion direction) while being inserted into the trocar positioned in the RCM, and the linear axis q 21 By moving the trocar in a straight line, the end effector moves while keeping the trocar in a fixed position. ee can be made to rotate.

[0046] Linear axis q 20 and linear axis q 21 can be configured as a linear slider on the driven shaft side in the coupling device according to the present disclosure, and can be made to perform linear motion by connecting with a linear actuator (neither of which is shown) on the drive shaft side installed outside the robot arm 700 (specifically, on the robot device main body side on which the robot arm 700 is mounted). 20 and linear axis q 21 The specific configuration and details of the coupling with the drive shaft will be described later.

[0047] In addition, the linear axis q 20 and linear axis q 21 is the active axis that is driven by connecting with the drive shaft, while the other linear axis q 19is the passive axis. This passive axis q 19 is link l ee Link with 17 and is inserted between the joint axis q 10 and q 11 Passive axis q is connected between 19 is the linear axis q 20 and linear axis q 21 The operation of the end effector ee While translating and rotating the link l 15 Link with 16 (and link 17 ) on a straight line, and the joint axes q 10 and q 11 It has the role of connecting the two freely. 19 is the joint axis q 10 , joint axis q 11 , and joint axis q 14 It moves linearly so that the YZ plane passing through is constrained.

[0048] The robot arm 700 having the joint link configuration shown in Figure 7 can also be assembled like origami. Figures 8 and 9 show an example of the configuration of the robot arm 700 using an origami structure. Figure 8 is a side view of the robot arm 700 having an origami structure viewed from the side, and Figure 9 is a perspective view of the robot arm 700 having an origami structure viewed from the distal end side. 20 and linear axis q 21 is linearly actuated by the transmission of power from the outside, but for the sake of simplicity, in Figs. 8 and 9, the linear axis q 20 and linear axis q 21 is omitted from the illustration.

[0049] First, the origami structure will be described. The robot arm 700 having the origami structure is constructed using plate-shaped members that can be bent to form a hinge structure. The bent portions of the plate-shaped members function as (rotational) joint axes, and the portions connecting the bent portions function as links. The joint portions of the plate-shaped members are flexible and configured to be elastically deformable, functioning as a hinge structure. The joint portions of the plate-shaped members are softer than the link portions; conversely, the link portions of the plate-shaped members have higher rigidity than the joint portions. For example, the thickness of the joint portions of the plate-shaped members is smaller than the thickness of the link portions. The joint portions may further include one or more holes (micropores). By making the joint portions of the plate-shaped members thinner or including holes, the joint portions can be made softer than the link portions, making them easier to bend.

[0050] The plate-like members can be made of materials such as carbon, iron, and composite materials. Different materials may be used for the joints and the links, and the joints 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 joints include polyimide, rubber, silicone, and elastomer.

[0051] Next, we will explain the link structure of the robot arm 700. 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 Figure 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.

[0052] The parallel link mechanism has a plurality of joint axes, which are joint axes q1 to q 21 (However, in FIGS. 8 and 9, the linear axis q 20 and linear axis q 21 (The illustration of joint axis q1, joint axis q2, joint axis q7, and joint axis q 10 is placed 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, the end effector 1 at the distal end is ee(The illustration is omitted.)

[0053] As shown in FIG. 7, the linear axis q 21 The linear motion of link l 12 , joint axis q 18 , Link 11 , and joint axis q 17 The force is transmitted through the link l4 to rotate around the joint axis q1. 20 The linear motion of link l8 and joint axis q 16 , link l7, and joint axis q 15 The force is transmitted through the link l9 to rotate around the joint axis q7. 20 and linear axis q 21 are configured as linear sliders on the driven shaft side in the coupling device according to the present disclosure, and can be linearly moved by connecting them to linear actuators on the driving shaft side (none of which are shown in FIGS. 7 to 9) installed below the base part of the robot arm 700. However, the linear movement axis q 20 and linear axis q 21 The specific configuration and details of the coupling with the drive shaft will be described later.

[0054] Multiple links l1 to l 15 and the distal end link (end effector) l ee (However, ee 8 and 9) extend in the XZ plane direction and connect the joint axes. Specifically, link l1 connects joint axis q1 and joint axis q2. Link l2 connects joint axis q2 and joint axis q3. Link l3 connects joint axis q3 and joint axis q4. Link l4 connects joint axis q1 and joint axis q4. Link l5 connects joint axis q3 and joint axis q5. Link l6 connects joint axis q5 and joint axis q6. 13 Link l7 connects joint axis q4 and joint axis q6. Link l 14 Link l connects joint axis q3 and joint axis q4. 15 is the joint axis q 12 and joint axis q 13 Connect the two.

[0055] 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 q 11 , joint axis q 12 , joint axis q 13 , joint axis q 14 , Link 12 , Link 14 , Link l6, Link l 15 The parallel link mechanism pl3, located between the parallel link mechanisms pl1 and 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.

[0056] Link 14 is an end effector such as a surgical tool at the distal end. ee (not shown in Figures 8 and 9). 14 The end effector l supported by ee The link 1 extends in the direction of insertion of the surgical tool into the body (or the eye). 13 is link l 14 and the end effector l ee When moving the link l in the insertion direction of the surgical instrument, 14 It moves parallel with

[0057] The joint axis q7 is provided between the joint axis q1 and the joint axis q2, and the joint axis q9 is provided between the joint axis q5 and the joint axis q6. Between the joint axis q7 and the joint axis q9, there is a link l9, a joint axis q 15 , Link 10 These components are made by joining plate-like members together to form a V-shape, as can be seen from Figures 8 and 9, and do not interfere with the operation of the parallel link mechanism pl1 and the parallel link mechanism pl2.

[0058] The linear axis q is the active axis 21 The linear motion of link l 12 , joint axis q 18 , Link 11 , and joint axis q 17 When the parallel link mechanism pl1 located on the base side is operated by the rotation of the link l4, the parallel link mechanism pl3 located between the parallel link mechanism pl1 and the parallel link mechanism pl2, and the parallel link mechanism pl2 located on the distal end side, operate in conjunction with each other, and the end effector l ee can be pivoted and moved in the insertion direction with the remote motion center RCM as a fixed point.

[0059] The linear axis q is the active axis 20 The linear motion of the link l8 and the joint axis q 16 , link l7, joint axis q 15 , and joint axis q 15 The force is transmitted through the link l9, which can rotate around the joint axis q7. 19 is link l 16 Link with 17 and is inserted between the joint axis q 10 and q 11 The linear axis q is connected between 19 is the linear axis q 20 While link l rotates around joint axis q by the action of 15 Link with 16 (and link 17 ) on a straight line, and the joint axes q 10 and q 11 The linear axis q is connected to the shaft. 20 The linear motion of the linear axis q 19 When the link l is displaced, the link l in the parallel link mechanism p12 located at the distal end side 15 moves in the extension direction, and therefore, link l 14 The end effector l supported by ee moves in the insertion direction.

[0060] In short, the linear axis q 19 is the end effector l according to the displacement amount ee Link l is inserted in the linear direction. 16 Link with 17 via the joint axis q 10 and joint axis q 11 In the implementation example of the origami structure, the linear axis q 19 is configured to deform in the plane direction of the YZ plane perpendicular to the XZ plane. 19 is the link l on the YZ plane. 16 Link with 17 The link mechanism deforms to have a V-shape.

[0061] At the bottom right of FIG. 8, a linear axis q consisting of a V-shaped link mechanism is shown. 19 The joint link configuration is shown. 19 is a passive axis, but the linear axis q 20 and linear axis q 21 The operation of the end effector ee While translating and rotating the link l 15 Link with 16 (and link 17 ) on a straight line, and the joint axes q 10 and q 11 Its role is to provide flexible connections between the

[0062] In the example shown in the lower right of FIG. 19 is the joint axis q 22 , joint axis q 23 , joint axis q 24 , joint axis q 25 , Link 18 , Link 19 , Link 20 , Link 21 Parallel link mechanism p1 consisting of 81 and joint axis q 23 , joint axis q 24 , joint axis q 26 , joint axis q 27 , Link 18 , Link 19 , Link20 , Link 21 Parallel link mechanism p1 consisting of 82 And, link l 20 Therefore, the linear axis q 19 is link l 20 The parallel link mechanism p 81 and parallel link mechanism pl 82 The parallel link mechanism pl has a V-shape. 81 and parallel link mechanism pl 82 When is collapsed, link l 20 is displaced in the surface direction of the YZ plane, and this is the linear axis q 19 The displacement of link l 18 Here is the link 16 connected to link l 23 Here is the link 17 is connected to.

[0063] C-2. Coupling structure applied to robot arm As mentioned in C-1 above, the two linear axes q 20 and linear axis q 21 can be configured as a linear slider on the driven shaft side in the coupling device according to the present disclosure, and can be operated in a linear motion by connecting with a linear actuator on the drive shaft side installed outside the robot arm 700 (specifically, on the robot device main body side on which the robot arm 700 is mounted). 20 and linear axis q 21 The specific configuration of the drive shaft and the coupling with the drive shaft side will be described in detail.

[0064] FIG. 10 shows a linear axis q located near the bottom of the robot arm 700. 20 and linear axis q 21 11 shows an external configuration (perspective view) of a drive unit 1000 on the drive shaft side that operates each of the above. Also, FIG. 11 shows a schematic diagram of the joint link configuration of the drive unit 1000.

[0065] As shown in FIG. 11, the drive unit 1000 has one linear axis q 20 and a linear actuator 1010 for driving the other linear axis q21 The actuator 1020 includes a linear actuator 1020 for driving the

[0066] 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 the motor q A,1 The motor q reciprocates along the guide rail in the longitudinal direction of the stator 1011. A,1 As long as the motor can be converted into power in the longitudinal direction of the stator 1011, it may be either a rotary motor or a linear motor.

[0067] Similarly, the other linear actuator 1020 includes a stator 1021, a rotor 1022, and a motor q A,2 and the rotor 1022 is a motor q A,1 The stator 1011 is configured to reciprocate in the longitudinal direction by the power from the rotor 1012.

[0068] Referring to FIG. 10 , the linear actuators 1010 and 1020 have stators 1011 and 1021 supported and fixed to a frame 1030 so that their respective longitudinal directions (i.e., the linear directions of the rotors 1012 and 1022) coincide with the X direction. The frame 1030 is formed, for example, by assembling a plurality of sheet metal parts using screw fastening or the like, as shown in the figure. The frame 1030 also has openings 1031 and 1032 for exposing the top surfaces of the rotors 1012 and 1022, respectively, over their respective ranges of motion in the X direction when the rotors 1012 and 1022 reciprocate in the X direction. The top surfaces C′1 and C′2 of the rotors 1012 and 1022 are coupling surfaces that couple with the rotors of the linear sliders on the driven shaft side. Therefore, the corresponding rotors on the drive shaft side and the driven shaft side can be coupled to each other via these openings 1031 and 1032.

[0069] Next, a description will be given of a method for connecting the robot arm 700 and the drive unit 1000. The principle of the coupling device according to the present disclosure is applied to the connection between the robot arm 700 and the drive unit 1000.

[0070] 12 shows a bottom view of the robot arm 700 on the driven axis side. 20 and linear axis q 21 are respectively configured using a linear slider 1210 and a linear slider 1220. As already explained with reference to FIG. 22, the linear slider 1210 and the linear slider 1220 are each composed of a stator and a rotor, the stator has a guide rail that guides and supports the rotor, and the rotor is mounted on the stator and can reciprocate along the guide rail in the longitudinal direction of the stator. Here, the linear motion axis q 20 and linear axis q 21 The stators of the linear sliders 1210 and 1220 are supported and fixed to the link l1 of the robot arm 700 so that the longitudinal direction (i.e., the linear direction of the rotor) coincides with the X direction. The longitudinal movement of the rotor on one side of the linear slider 1210 is along the linear axis q 20 The rotor on the other linear slider 1220 side moves in the longitudinal direction along the linear axis q 21 The behavior is as follows.

[0071] Link l is made of a flat part made of sheet metal or the like, and has openings 1231 and 1232 for exposing the top surface of each rotor over the range of motion when each rotor of linear slider 1210 and linear slider 1220 reciprocates in the X direction. Top surfaces C and C of each rotor are connecting surfaces for connecting with top surface C' of rotor 1012 of linear actuator 1010 on the drive shaft side and top surface C' of rotor 1022 of linear actuator 1020, respectively.

[0072] 13 shows a top view of the drive unit 1000 on the drive shaft side. As already explained 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.

[0073] As can be seen from Figures 12 and 13, the corresponding rotors on the drive shaft side and the driven shaft side can be brought into contact with each other through 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.

[0074] The robot arm 700 and the drive unit 1000 are connected by magnetic attraction.

[0075] On the robot arm 700 side, magnets 1251 and 1252 are arranged on the upper surface C1 of the rotor of linear slider 1210, and magnets 1253 and 1254 are arranged on the upper surface C2 of the rotor of linear slider 1220. In addition, four magnets 1255 to 1258 are arranged on link l1 that supports and fixes the stators of linear slider 1210 and linear slider 1220.

[0076] On the other hand, on the drive unit 1000 side, magnets 1351 and 1352 are arranged on the upper surface C'1 of rotor 1012 of linear actuator 1010, and magnets 1353 and 1354 are arranged on the upper surface C'2 of rotor 1022 of linear actuator 1020. Four magnets 1355 to 1358 are arranged on the upper surface of frame portion 1030 that supports and fixes stator 1011 of linear actuator 1010 and stator 1021 of linear actuator 1020. The positions of these magnets 1355 to 1358 correspond to the positions of the four magnets 1255 to 1258 arranged on link l1 on the robot arm 700 side.

[0077] 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 FIGS. 12 and 13 , magnets 1251 to 1258 arranged on the robot arm 700 side are all set to south poles, and magnets 1351 to 1358 arranged on the drive unit 1000 are all set to north poles. However, the polarity combinations are not limited to these, and other polarity combinations may be used as long as an attractive force is generated between opposing magnets. The magnets 1251 to 1258 and the magnets 1351 to 1358 may be fixed by adhesive, and the use of heat-resistant magnets allows the use of a thermosetting adhesive (same as above).

[0078] 14 to 16, the robot arm 700 and the drive unit 1000 can be connected by the attractive force of the corresponding magnets simply by placing the robot arm 700 on the drive unit 1000. As already explained with reference to FIG. 4, the alignment required 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 attractive force of the magnets.

[0079] Furthermore, when the robot arm 700 and the drive unit 1000 are connected with their longitudinal orientations aligned, the rotors of the corresponding linear slider and linear actuator may not be aligned in position, resulting in the rotors not being aligned. In such a case, for example, by moving the rotor of the linear actuator in the longitudinal direction (X direction) using a return-to-origin operation, the rotors will be aligned with the corresponding rotor of the linear slider due to the magnetic attraction (see, for example, FIG. 5).

[0080] The only alignment required when connecting the robot arm 700 and the drive unit 1000 is orientation around one axis, the longitudinal rotation. This alignment can be made even easier by using positioning pins. In the example shown in FIGS. 12 and 13 , positioning pins 1341 and 1342 are attached to the frame portion 1030 of the drive unit 1000, which is the drive shaft side, while pin holes 1241 and 1242 are drilled in the link l1, which is the bottom surface of the robot arm 700, which is the driven shaft side, at locations opposite 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 fit into the pin holes 1241 and 1242, respectively, alignment between the stators 112 and 122 can be easily achieved.

[0081] 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 below.

[0082] The adoption of a coupling structure utilizing the magnetic attraction and positioning pins facilitates alignment work when attaching the robot arm 700 to the drive unit 1000. Furthermore, the robot arm 700 can be detached from the drive unit 1000 simply by pulling it against the magnetic attraction, reducing the workload of attachment and detachment and facilitating replacement of the robot arm 700. Therefore, non-engineers such as surgeons or assistants can replace the robot arm 700 during operation, achieving a highly reproducible coupling.

[0083] The robot arm 700 and the drive unit 1000 are configured to use magnetic attraction and friction for coupling and thrust transmission. A,1 and actuator q A,2 The power generated by each of the above is transmitted to the linear axis q of the robot arm 700 without backlash. 20 and linear axis q 21, and as a result, the end effector (surgical tool) 1 at the distal end of the robot arm 700 ee can be operated with high precision.

[0084] 12, the structure of the connecting portion of the robot arm 700 with the drive unit 1000 is simplified. This simplifies the manufacturing process and leads to lower costs. Furthermore, because the robot arm 700 has a simple, uncomplicated structure overall, including the connecting portion with the drive unit 1000, gas can easily penetrate during gas sterilization, facilitating the sterilization process.

[0085] 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.

[0086] 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.

[0087] 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 1711 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).

[0088] The surface-to-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, respectively, and magnet 1715 is arranged on the upper 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, respectively, and magnet 1725 is arranged on the upper 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, respectively.

[0089] Due to precision errors in machining, for example, on the linear slider 1710 side, a discrepancy may occur between the height of the magnets 1713 and 1714 arranged on the stator 1712 and the height of the magnet 1715 arranged on the rotor 1711. Components such as the rotor 1711 and the stator 1712 are expected to be manufactured by cutting, and machining errors are difficult to ignore. Similarly, on the linear actuator 1720 side, a discrepancy may occur between the height of the magnets 1713 and 1714 arranged on the stator 1712 and the height of the magnet 1715 arranged on the rotor 1711.

[0090] If the magnetic contact between the rotor 1711 on the driven shaft and the rotor 1721 on the driving shaft is insufficient due to a difference in height between the magnets, the magnetic attraction force will be reduced, resulting in a problem of reduced transmission efficiency when power is transmitted from the rotor 1721 on the driving shaft to the rotor 1711 on the driven shaft due to a weakened friction force in the thrust direction.

[0091] 17 shows a modified example in which the magnets are attached via a means for compensating for the height difference. 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 difference. As a result, rotor 1711 on the driven shaft and rotor 1721 on the driving shaft are brought into 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 to rotor 1711 on the driven shaft.

[0092] FIG. 18 shows another modified example configured to mount magnets via a means for compensating for height discrepancies. In the coupling device 1800 according to the modified example shown in FIG. 18, a rotor 1711, to which a magnet 1715 is attached, is attached to a stator 1712 via a base 1803 supported by springs 1801 and 1802. The stator 1712 has a recess that allows the base 1803 to move in the height direction, and the base 1803 is attached to the recess via springs 1801 and 1802. It is preferable that the springs 1801 and 1802 are the same component. The springs 1801 and 1802 apply a preload in the height direction to the rotor 1711 (and the magnet 1715). Therefore, the height discrepancy is compensated for so that the magnet 1715 attached to the rotor 1711 does not become 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 power transmission efficiency from the rotor 1721 on the driving shaft side to the rotor 1711 on the driven shaft side.

[0093] FIG. 19 shows yet another modified example configured to attach magnets via a means for compensating for height discrepancies. In the coupling device 1900 according to the modified example shown in FIG. 19 , a rotor 1711, to which a magnet 1715 is attached, is attached to a stator 1712 via an air gap 1901. The stator 1712 has a recess that allows a 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). Therefore, the height discrepancy is compensated for so that the magnet 1715 attached to the rotor 1711 does not become 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 power transmission efficiency from the rotor 1721 on the driving shaft side to the rotor 1711 on the driven shaft side.

[0094] As a means for compensating for the height discrepancy, in addition to a spring or an air gap, various flexible parts that act on a magnet with a preload in the height direction can be used. Although Figures 17 to 19 show modified examples in which a means for compensating for the height discrepancy is provided on the linear slider 1710 side, a configuration in which a means for compensating for the height discrepancy is provided on the linear actuator 1720 side may also be used.

[0095] Although not shown in Figures 17 to 19, in all of the modified examples, by combining the attachment of a positioning pin to the stator on the linear actuator side with the provision of a pin hole for fitting in the stator on the linear slider side (see, for example, Figure 6), it is possible to easily adjust the orientation of one axis of rotation in the longitudinal direction.

[0096] 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.

[0097] E-1. Schematic Configuration of Medical Robot System Figure 20 shows an example of the schematic configuration of a medical robot system 2000 used in surgical operations. The types of surgery referred to here include laparoscopic surgery, laparoscopic surgery, superficial surgery, and ophthalmic (eye or fundus) surgery, but the following explanation will be focused primarily on ophthalmic surgery.

[0098] The medical robot system 2000 is of a master-slave type and comprises a master device 2010, which a user such as a surgeon instructs to operate a surgical tool, and a slave device 2020, which drives the surgical tool in accordance with 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.

[0099] The master device 2010 is placed outside the operating room or in a location within the operating room away from the operating table. On the master device 2010 side, a surgical field image 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 remotely instructs the operation of a surgical tool by manually operating an operation input device 2012 while observing the surgical field image. The operation input device 2012 is a manipulator that can perform, for example, three translational degrees of freedom for instructing translational movement of the surgical tool T, three rotational degrees of freedom for instructing a change in posture of the surgical tool T, and one grasping degree of freedom for opening and closing forceps, etc.

[0100] On the other hand, the slave device 2020 is placed near the operating table and drives surgical tools in accordance with instructions from the master device 2010 to perform surgery on a patient lying on the operating table. The slave device 2020 also transmits surgical field images captured by a camera and other sensor information to the master device 2010, which then provides feedback to a user such as a surgeon.

[0101] 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 captured 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.

[0102] The first robotic device 2021 and the second robotic device 2022 are positioned near the operating table.

[0103] 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, as shown in Figures 7 to 9, for example, and can pivot or 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 depicted in a simplified form to avoid cluttering the drawing.

[0104] 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. Furthermore, the second robot device 2022 is intended to be manually operated by a user, such as a surgeon or an assistant, who directly applies force to the second robot device. However, some of the joint axes may be active joints, and the operation of the active joints may be controlled by the master device 2010. The second robot device 2022 is fixed to a mechanical ground at its base 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. For example, the rails may be laid in an arc shape around the patient's head.

[0105] The principle of the coupling device according to the present disclosure is applied to coupling the first robotic device 2021 to the distal end of the second robotic device 2022. The first robotic device 2021 is on the driven shaft side, and the second robotic device 2022 is on the driving shaft side. The first robotic device 2021 realizes pivotal and translational movements of the surgical tool T by power transmitted from the second robotic device 2022. The first robotic device 2021 is detachably and replaceably attached to the second robotic device 2022. When it is desired to replace the surgical tool T, the first robotic device 2021 is removed from the second robotic device 2022, and another first robotic device 2021 supporting a new surgical tool T' is attached to the second robotic device 2022. The first robotic device 2021 may be disposable.

[0106] The first robot device 2021 is a robot arm having an origami structure, which is configured by combining a plurality of parallel links, as shown in Figures 7 to 9. The first robot device 2021 supports a surgical tool T at its distal end, and has linear axes q on its bottom surface, which are respectively involved in the pivotal movement and translational movement of the surgical tool T. 20 and linear axis q21 The rotor of each linear slider is positioned to transmit power to the rotor (see, for example, FIG. 12).

[0107] On the other hand, the distal end of the second robot device 2022 is provided with a linear axis q 20 and linear axis q 21 The drive unit is mounted to operate each of the linear axis q. A,1 and q A,2 The rotors of these linear actuators are connected to the rotor (described above) on the bottom surface of the first robot device 2021, thereby making it possible to transmit power to the first robot device 2021.

[0108] Linear axis q on the first robot device 2021 side 20 and linear axis q 21 is the driven axis, and the linear axis q A,1 and q A,2 is the drive shaft. A linear motion system is adopted for these drive shafts and driven shafts, and the drive shaft and driven shaft are connected by a surface joint that utilizes the attractive force of magnets. Therefore, complex alignment or orientation is not required between the first robot device 2021 and the second robot device 2022. That is, as shown in FIGS. 14 to 16 , the first robot device 2021 can be connected to the second robot device 2022 simply by placing the first robot device 2021 on the distal end of the second robot device 2022. Furthermore, after connection, power can be transmitted from the second robot device 2022 to the first robot device 2021 precisely and without backlash using the attractive force and friction of the magnets.

[0109] The first robotic device 2021 is driven by a linear actuator and is capable of precise operation with a precision of, for example, about 10 microns, and can be called a "fine-motion robot." In contrast, the second robotic device 2022 can also be called a "coarse-motion robot" because it is manually operated. During surgery, the second robotic device 2022 can be draped to effectively separate clean and non-clean areas.

[0110] 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 moves the second robot device 2022 under guidance 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.

[0111] The first robot device 2021 can be remotely controlled from the master device 2010. A user such as a surgeon can manually operate the operation input device 2012 to instruct the pivotal and translational movements of the surgical tool T. In addition, sensor information such as external forces applied to the surgical tool T is fed back to the master device 2021. Using two-way communication between the master device 2010 and the slave device 2020, bilateral control is performed so that the displacement amounts and forces correspond between the master device 2010 and the slave device 2020.

[0112] Motion scaling may be used so that the physical displacement amount of the user manually operating 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 side, making remote surgery easier. Note that the user manually operating the operation input device 2012 and the user manually operating the second robotic device 2022 may be the same or different. For example, the user manually operating the operation input device 2012 may be the surgeon, and the user manually operating the second robotic device 2022 may be an assistant.

[0113] If a different surgical tool T' needs to be used 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 retracted from the affected area, and the first robotic device 2021 is detached from the second robotic device 2022 in a safe location. Because the first robotic device 2021 and the second robotic device 2022 are connected only by magnetic attraction, this detachment can be performed simply by lifting the first robotic device 2021. Thereafter, the surgical tool replacement is completed by the simple operation of 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). Furthermore, as described above, the clean area and the non-clean area can be effectively separated. The user, such as the surgeon, can then resume the surgery using a new surgical tool T'.

[0114] 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 explained.

[0115] 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 includes 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 in accordance with instructions from the master device 2010. 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 so that the displacement amount and force correspond to each other.

[0116] 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.

[0117] 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. 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 grasping degree of freedom, such as opening and closing forceps (if 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.

[0118] 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.

[0119] 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, with motors, at least some of the axes of a manipulator (described above) that has three translational degrees of freedom, a rotational degree of freedom, and a grasping degree of freedom. 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 when 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 motors of the manipulator.

[0120] 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 converter that converts electrical signals sent from the master device 2010 into optical signals, and an optical-to-electrical converter that converts optical signals received from the transmission path 2030 into electrical signals. The master-side communication unit 2114 transfers operation commands for the surgical robot 2122 input by the user (operator) 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.

[0121] 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 operates in accordance with instructions from the master device 2010 under the overall control of the slave-side control unit 2121.

[0122] The surgical robot 2122 includes a first robotic device 2021 and a second robotic device 2022 shown in FIG. 20 . The second robotic device 2022 is coupled to the first robotic device 2021 at its tip, and the first robotic device 2021 supports a surgical tool T at its distal end. As described above, the coupling principle of the present disclosure is applied to the coupling between the first robotic device 2021 and the second robotic device 2022. The slave-side control unit 2121 interprets operation commands sent from the master device 2010 via the transmission path 2030, converts the commands into drive signals for driving the drive shaft for pivoting and translating the surgical tool T, and outputs the drive signals to linearly move the drive shaft on the second robotic device 2022 side. When power is transmitted to the driven shaft on the first robotic device 2021 side without backlash due to the magnetic attraction force and frictional force, the surgical tool at the distal end pivots and translates via the parallel link mechanism.

[0123] The sensor unit 2123 is equipped with a plurality of 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 external forces and moments 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 taken by the microscope 2023.

[0124] 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.

[0125] The slave-side communication unit 2124 transfers force data of the surgical tool acquired by the sensor unit 2123 and images of the surgical field 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.

[0126] 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.

[0127] A coupling structure utilizing magnetic attraction and a positioning pin is used to connect the first robotic device 2021, which is the driven shaft side, and the second robotic device 2022, which is the driving shaft side, making alignment during installation easy. Furthermore, the first robotic device 2021 can be detached from the second robotic device 2022 simply by pulling against the magnetic attraction, reducing the workload of attachment and detachment, and allowing for easy replacement of the surgical tool T as a single unit with the first robotic device 2021. Therefore, non-engineers such as surgeons or assistants can replace the surgical tool T during surgery, achieving a highly reproducible coupling.

[0128] 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 frictional force. 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.

[0129] As shown in Figure 12, the first robot device 2021 is made up of a robot arm with a simplified structure for the connecting portion. This simplifies the manufacturing process and leads to lower costs. Furthermore, the first robot device 2021 has a simple structure that is not complicated overall, including the connecting portion with the second robot device 2022, which allows for easy penetration during gas sterilization and facilitates the sterilization process.

[0130] Section B above explained that, with the coupling device according to the present disclosure, when a load is applied to the driven shaft in the opposite direction to the thrust transmitted from the drive shaft, and the relationship "thrust ≧ load" holds 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 "thrust ≧ load" holds, allowing for precise power transmission. Therefore, the medical robot system 2000 enables precise and minimally invasive surgery.

[0131] The present disclosure has been described in detail above with reference to specific embodiments. However, the present disclosure should not be construed as being limited to the above-described embodiments, and it is obvious that those skilled in the art can modify or substitute the embodiments without departing from the spirit 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 thereto, and additional effects not described in this specification may exist.

[0132] 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 (e.g., a medical manipulator system), the gist of the present disclosure is not limited thereto. 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 at nuclear power plants, thermal power plants, and petrochemical plants, part transport and assembly work at manufacturing plants, cleaning in high-rise buildings, and rescue at fire scenes and other locations.

[0133] In short, the present disclosure has been described in the form of examples, and the contents of the specification should not be interpreted as limiting. To determine the gist of the present disclosure, the claims should be taken into consideration.

[0134] The present disclosure may also be configured as follows.

[0135] (1) A coupling device comprising: a linear-acting driven shaft; a linear-acting driving shaft; and a connecting portion that connects the driven shaft and the driving shaft by surface contact.

[0136] (2) The coupling device described in (1) above, wherein the driven shaft portion includes a linear slider including a first rotor and a first stator, the drive shaft portion includes a linear actuator including a second rotor and a second stator, and the connecting portion connects the first rotor and the second rotor, and the first stator and the second stator, respectively, by surface contact so that the moving directions of the first rotor and the second rotor are the same.

[0137] (3) The coupling device according to (2) above, wherein one of the first stator and the second stator has a positioning pin, and the other has a pin hole that fits with the positioning pin.

[0138] (4) The coupling device according to any one of (2) or (3), wherein the connecting portion utilizes the attractive force of a magnet to connect the first rotor and the second rotor, and the first stator and the second stator.

[0139] (5) The coupling device described in (4) above, wherein 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 arranged on the second stator at locations corresponding to the first magnets attached to the first stator.

[0140] (6) The coupling device described in (5) above, wherein 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.

[0141] (6-1) The coupling device according to (6) above, wherein the buffer member is a spring, an air gap, or other flexible component that applies a preload to the magnet in the height direction.

[0142] (7) The coupling device according to any one of (4) to (6), wherein the connecting portion connects the first rotor to the second rotor by moving the second rotor on the second stator after the first stator and the second stator are connected.

[0143] (8) A medical robot device comprising: a first robot device that supports a surgical tool at a distal end; and a second robot device that is connected to the first robot device, wherein a linear motion driven shaft portion of the first robot device and a linear motion driving shaft portion of the second robot device are connected by a surface joint, and the first robot device operates the surgical tool by power transmitted from the driving shaft portion to the driven shaft portion.

[0144] (9) The medical robot device according to (8), wherein the first robot device supports the surgical tool so as to have a remote center of motion.

[0145] (10) The medical robot device according to any one of (8) or (9), wherein the second robot device is detachably connected to the first robot device.

[0146] (11) A medical robot device according to any one of (8) to (10) above, wherein the driven shaft comprises a linear slider including a first rotor and a first stator, the drive shaft comprises a linear actuator including a second rotor and a second stator, and the first rotor and the second rotor, and the first stator and the second stator are connected by surface joints so that the directions of movement of the first rotor and the second rotor are the same.

[0147] (12) The medical robot device according to (11), wherein one of the first stator and the second stator has a positioning pin, and the other has a pin hole that fits with the positioning pin.

[0148] (13) The medical robot device according to any one of (11) or (12) above, wherein the first rotor and the second rotor, and the first stator and the second stator are connected to each other by utilizing the attractive force of a magnet.

[0149] (14) The medical robot device described in (13) above, wherein 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, and the second magnets are arranged on the second stator at locations corresponding to the first magnets attached to the first stator.

[0150] (15) The medical robot device described in (14) above, wherein 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 the 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 the height difference.

[0151] (16) The medical robot device according to any one of (13) to (15), wherein, 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.

[0152] (17) A medical robot device comprising: a link mechanism that supports a surgical instrument at a distal end; and a linear-motion driven shaft that is detachably connected to a linear-motion driving shaft by a surface joint; wherein the linear-motion driven shaft drives the link driving section by power transmitted from the linear-motion driving shaft.

[0153] (17-1) The medical robot device according to (17), wherein the link mechanism supports the surgical tool so as to have a remote center of motion.

[0154] (18) The medical robot device described in (17) above, wherein the driven shaft portion comprises a linear slider including a first rotor and a first stator, the drive shaft portion comprises a linear actuator including a second rotor and a second stator, and the first rotor and the second rotor, and the first stator and the second stator are respectively connected by surface joints so that the moving directions of the first rotor and the second rotor are the same.

[0155] (19) The medical robot device according to (18), wherein the first stator has a pin hole that fits with a positioning pin provided on the second stator on the drive shaft side.

[0156] (20) The medical robot device described in either (18) or (19) above, wherein 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.

[0157] (20-1) A medical robot device as described in (20) above, further comprising a plurality of first magnets attached to each of the first rotor and the first stator of the driven shaft, wherein the first magnets attached to the first stator are positioned at locations corresponding to the second magnets attached to the second stator of the drive shaft.

[0158] (20-2) The medical robot device according to (20-1) above, wherein 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.

[0159] DESCRIPTION OF SYMBOLS 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 part 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

1. A coupling device comprising: a linear motion driven shaft portion; a linear motion driving shaft portion; and a connecting portion that connects the driven shaft portion and the driving shaft portion by a surface joint.

2. The coupling device according to claim 1, wherein the driven shaft portion comprises a linear slider including a first rotor and a first stator, the drive shaft portion comprises a linear actuator including a second rotor and a second stator, and 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.

3. The coupling device according to claim 2, wherein one of said first stator and said second stator has a positioning pin, and the other has a pin hole that fits with said positioning pin.

4. The coupling device according to claim 2, wherein the connecting portion utilizes the attractive force of a magnet to connect the first rotor and the second rotor, and the first stator and the second stator.

5. A coupling device as described in claim 4, wherein the coupling portion includes a plurality of first magnets attached to each of the first rotor and first stator of the driven shaft portion, and a plurality of second magnets attached to each of the second rotor and second stator of the drive shaft portion, and the second magnets are arranged on the second stator at locations corresponding to the first magnets attached to the first stator.

6. A coupling device as described in claim 5, wherein 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.

7. The coupling device according to claim 4, wherein the coupling portion couples the first rotor to the second rotor through an action of moving the second rotor on the second stator after the first stator and the second stator are coupled.

8. A medical robot device comprising: a first robot device that supports a surgical tool at a distal end; and a second robot device that connects to the first robot device, wherein a linear motion type driven shaft portion of the first robot device and a linear motion type driving shaft portion of the second robot device are connected by a surface joint, and the first robot device operates the surgical tool by power transmitted from the driving shaft portion to the driven shaft portion.

9. The medical robotic device according to claim 8, wherein the first robotic device supports the surgical tool so as to have a remote center of motion.

10. The medical robotic device according to claim 8, wherein the second robotic device is detachably connected to the first robotic device.

11. The medical robot device of claim 8, wherein the driven shaft comprises a linear slider including a first rotor and a first stator, the drive shaft comprises a linear actuator including a second rotor and a second stator, and the first rotor and the second rotor, and the first stator and the second stator are respectively connected by surface joints so that the moving directions of the first rotor and the second rotor are aligned.

12. The medical robot device according to claim 11, wherein one of the first stator and the second stator has a positioning pin, and the other has a pin hole that fits with the positioning pin.

13. The medical robot device according to claim 11, wherein the first rotor and the second rotor, and the first stator and the second stator are respectively connected to each other by utilizing the attractive force of a magnet.

14. The medical robot device of claim 13, wherein 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, and the second magnets are disposed on the second stator at locations corresponding to the first magnets attached to the first stator.

15. The medical robot device according to claim 14, wherein the first robot device has the first magnet attached to at least one of the first rotor and the first stator via a mitigation member that mitigates the height discrepancy, or the second robot device has the second magnet attached to at least one of the second rotor and the second stator via a mitigation member that mitigates the height discrepancy.

16. The medical robotic device of claim 13, wherein after the first stator and the second stator are coupled, the second robotic device couples the first rotor to the second rotor through an action of moving the second rotor on the second stator.

17. A medical robot device comprising: a link mechanism section that supports a surgical instrument at a distal end; and a linear motion driven shaft section that is detachably connected to a linear motion driving shaft section by a surface joint, wherein the linear motion driven shaft section drives the link driving section by power transmitted from the linear motion driving shaft section.

18. The medical robot device described in claim 17, wherein the driven shaft portion comprises a linear slider including a first rotor and a first stator, the driving shaft portion comprises a linear actuator including a second rotor and a second stator, and the first rotor and the second rotor, and the first stator and the second stator are respectively connected by surface joints so that the moving directions of the first rotor and the second rotor are aligned.

19. The medical robot device according to claim 18, wherein the first stator has a pin hole that fits with a positioning pin provided on the second stator on the drive shaft portion side.

20. The medical robot device according to claim 18, wherein 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 attractive forces.

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