WO2019039131A1 - Parallel link device and master-slave system - Google Patents

Abstract

Provided are a parallel link device and a master-slave system which utilizes the parallel link device. This parallel link device is provided with: a stationary section having a plurality of actuators; a plurality of link sections individually connected to the stationary section through the plurality of actuators; and a movable section supported by the plurality of link sections. The actuators each incorporate a motor, an encoder which detects the rotational angle of the output shaft of the motor, a torque sensor which detects torque acting on the output shaft of the motor, and a brake which stops the rotation of the motor.

Description

Parallel link device and master-slave system

The technology disclosed herein relates to a parallel link device and a master-slave system using the parallel link device.

The parallel link device has features such as being able to make the movable part to be a hand very light, to be able to be configured relatively inexpensively, and to be able to collect and arrange the motors for driving at the root, so there is no need to move the motor itself. doing. In recent years, parallel link devices have attracted attention as robots for various industries, such as transport and packing operations in industrial applications and master consoles for medical applications.

The parallel link device is basically configured by combining a plurality of actuators and a link mechanism. For example, it comprises three sets of parallel link mechanisms, three sets of motorized links for driving each parallel link mechanism, and an output member connected to the distal end of each parallel link mechanism and to which an end effector such as a surgical instrument is attached Parallel link devices are known (see, for example, Patent Document 1). Vertical and horizontal movement of the output member, that is, the end effector can be realized by the rotational drive of the three motors via parallel link mechanisms.

Japanese Patent Publication No. 4-45310 JP, 2016-83581, A

An object of the technology disclosed in the present specification is to provide a parallel link device and a master-slave system using the parallel link device.

According to a first aspect of the technology disclosed in the present specification, a fixing unit having a plurality of actuator units, a plurality of link units each connected to the fixing unit via the plurality of actuator units, and a plurality of links A movable unit supported by the drive unit, the actuator unit including a motor, an encoder for detecting a rotation angle of an output shaft of the motor, a torque sensor for detecting a torque applied to the output shaft of the motor, and the motor The parallel link device incorporates a brake for stopping the rotation of the.

The parallel link device according to the first aspect can be applied to, for example, either or both of the master side and the slave side in a master-slave system. Further, when applied to the slave side, the movable portion may be configured to be able to connect a medical unit such as an endoscope, a microscope, a catheter system, forceps, forceps, or a cutting instrument. Further, a force sensor may be disposed on the movable portion.

The parallel link device according to the first aspect may further include a control unit that controls the operation of the brake. Then, when an abnormality occurs in the parallel link device or any of the actuator units, the control unit operates the brake to stop the operation of the actuator unit or the entire parallel link device. You may make it The control unit can detect an abnormality based on, for example, a detection result of the torque sensor or the encoder.

A second aspect of the technology disclosed in the present specification includes a master device and a slave device, and at least one of the master device and the slave device includes an actuator that incorporates a motor, an encoder, a torque sensor, and a brake. A master-slave system having a parallel link device operating as a drive source.

However, the term "system" as used herein refers to a logical aggregation of a plurality of devices (or functional modules for achieving a specific function), and each device or functional module is in a single housing. It does not matter whether it is or not.

For example, both the master device and the slave device have the parallel link device, and the motor of the actuator of the slave device according to the detection result of the encoder of the actuator of the master device according to a bilateral control method. While driving the motor of the actuator of the master device according to the detection result of the torque sensor of the actuator of the slave device.

The driving of the actuator may be stopped by operating the brake based on the detection result of the torque sensor or the detection result of the encoder.

According to the technology disclosed herein, it is possible to provide a parallel link device and a master-slave system using the parallel link device.

The effects described in the present specification are merely examples, and the effects of the present invention are not limited thereto. In addition to the effects described above, the present invention may exhibit additional effects.

Other objects, features, and advantages of the technology disclosed herein will be apparent from the more detailed description based on the embodiments described below and the accompanying drawings.

FIG. 1 is a diagram showing an example of the functional configuration of a master-slave robot system 1. FIG. 2 is a diagram showing a configuration example of the parallel link device 200. As shown in FIG. FIG. 3 is a cross-sectional view of the actuator device 300. As shown in FIG. FIG. 4 is an exploded perspective view of the actuator device 300. FIG. 5 is an enlarged view of components on the input side of the actuator device 300. As shown in FIG. FIG. 6 is an enlarged view of components on the output side of the actuator device 300. As shown in FIG. FIG. 7 is an enlarged view of a region 304 in FIG. FIG. 8 is a view schematically showing a cross section by the line AA shown in FIG. FIG. 9 is a cross-sectional view of the actuator device 1000. FIG. 10 is an exploded perspective view of the actuator device 1000. FIG. FIG. 11 is a flowchart showing a schematic processing procedure for stopping the operation of parallel link apparatus 200 in response to the detection of an abnormality. FIG. 12 is a view schematically showing a control block diagram of the actuator device 300. As shown in FIG. FIG. 13 is a diagram showing a hardware configuration of the information processing apparatus 2100.

Hereinafter, embodiments of the technology disclosed herein will be described in detail with reference to the drawings.

FIG. 1 schematically shows an example of the functional configuration of a master-slave robot system 1 to which the technology disclosed in this specification can be applied. The illustrated robot system 1 is a medical robot system that performs endoscopic surgery such as, for example, the abdominal cavity and the chest cavity. Support arm device on the slave side (not shown in FIG. 1) and an end effector such as a medical instrument attached to the support arm device according to an instruction input by the user via the input device such as a controller on the master side Is driven, and the medical instrument performs various treatments on the operative part of the patient.

The illustrated robot system 1 comprises a master device 10, a slave device 20, and a control system 30 for driving the slave device 20 in accordance with a user's instruction input via the master device 10. When the user operates the master device 10, an operation command to the slave device 20 is transmitted by the wired or wireless communication means through the control system 30, and the slave device 20 is operated.

The master device 10 includes an input unit 11 for a user such as an operator to perform an input operation, and a force presentation unit 12 for presenting a force to the user operating the input unit 11.

The input unit 11 can be configured by, for example, an input mechanism such as a lever, a grip, a button, a jog dial, a tact switch, and a foot pedal switch. However, the specific configuration of the input unit 11 is not limited to the above, and various known configurations that can be provided in an input device of a general master-slave robot system can be used.

Further, the force presentation unit 12 is configured by, for example, a servomotor that drives a lever or a grip that constitutes the input unit 11, and a servomotor that drives a support arm device that supports the input unit 11. The force presentation unit 12 drives, for example, a lever, an arm, or the like that configures the input unit 11 so as to give resistance to the operation of the input unit 11 by the user according to the force acting on the medical device on the slave device 20 side. (Also referred to as haptic feedback) presents the user with the force acting on the medical device.

On the other hand, the slave device 20 includes a support arm device having a surgical tool such as forceps attached to the tip (end effector), a drive unit 21 for driving the support arm device and the surgical tool at the tip, and a state in the support arm device. A state detection unit 22 for detecting is provided. In addition to the forceps, the tip of the support arm device may be attached with an imaging device such as a medical instrument, a catheter system, an endoscope or a microscope that touches the patient during surgery such as a forceps or a cutting instrument. .

The illustration of the support arm device is omitted in FIG. 1 for the sake of convenience. The support arm device has six degrees of freedom of position and orientation for changing the position and orientation of the end effector in three-dimensional space, and also has one degree of freedom for grasping the object by forceps attached to the tip.

The drive unit 21 corresponds to, for example, an actuator unit for driving a link mechanism that constitutes the support arm device. Further, in the case of a medical instrument having a drive portion such as forceps attached to the tip of the support arm device, the drive unit 21 also corresponds to a motor for operating the drive portion. By driving the motor according to the control amount calculated by the control system 30, the arm unit and the medical instrument operate as instructed by the user via the master device 10.

The state detection unit 22 includes, for example, a force sensor (torque sensor) that detects an external force acting on each link of the support arm device, an encoder that detects a rotation angle of a joint, or the like. In the present embodiment, the torque sensor and the encoder are incorporated in an actuator unit for driving a joint, but the details will be described later.

The control system 30 realizes, between the master device 10 and the slave device 20, drive control of the support arm device on the slave device 20 side and information transmission regarding force presentation to the master device 10 side. However, part or all of the functions of the control system 30 may be provided in at least one of the slave device 20 or the master device 10. For example, a central processing unit (CPU) (not shown) of at least one of the master device 10 and the slave device 20 functions as the control system 30. Alternatively, the CPUs of the master device 10 and the slave device 20 cooperate to function as the control system 30. The specific configuration of the control system 30 will be described later.

Note that FIG. 1 illustrates only the configuration that is particularly necessary to describe an embodiment according to the technology disclosed in the present specification. The robot system 1 may include other functional blocks that a general master-slave robot system has, in addition to the illustrated functional blocks. Various well-known configurations can be applied to configurations whose illustration is omitted, so the detailed description thereof is omitted in the present specification.

When driving control of the slave device 20 from the master device 10 side, information indicating an instruction for driving the support arm device input by the user via the input unit 11 of the master device 10 is transmitted to the control system 30. Be done. As in the case of the robot forceps described above, when the medical instrument has a drive part, the information indicating the instruction for driving the medical instrument input through the input unit 11 is also a master device. 10 may be input to control system 30.

The control system 30 calculates a control amount for driving the support arm device on the slave device 20 side based on the instruction input from the user via the input unit 11. For example, when drive control of the support arm device is performed by force control, the control system 30 generates, as the control amount, each joint necessary to realize the desired operation instructed by the user. Calculate the torque to be calculated. If the medical device has a drive part, the control system 30 calculates a control amount for driving the medical device.

Information on the control amount calculated by the control system 30 is transmitted to the drive unit 21 on the slave device 20 side. The drive unit 21 drives each joint of the support arm device according to the control amount calculated by the control system 30, and the support arm device operates as instructed by the user via the input unit 11. Further, if the medical instrument attached to the tip of the support arm device has a drive part, the user drives the motor for operating the drive part according to the control amount calculated by the control system 30. The medical device operates as instructed by the input unit 11.

In addition, while the support arm device and the medical instrument at the tip thereof are operating, the state detection unit 22 including a torque sensor, an encoder, etc. is a force (torque) acting on each joint, a rotation angle of each joint, etc. Is detected as a state in the support arm device. Information indicating the state of the support arm device detected by the state detection unit 22 is transmitted to the control system 30. The control system 30 sequentially grasps the current state of the support arm device based on the information, and calculates the above-mentioned control amount based on the current state of the grasped support arm device.

Here, it is presumed that the force acting on each joint detected by the force sensor reflects the force acting on the medical instrument attached to the tip of the support arm device. The control system 30 extracts the component of the force acting on the medical instrument from the forces acting on the respective joints detected by the force sensor, and transmits the components to the force presentation unit 12 of the master device 10. The force presentation unit 12 drives a lever or the like that configures the input unit 11 so as to give resistance to the operation of the input unit 11 by the user who is an operator, for example, according to the force acting on the medical instrument. Present the force acting on the medical instrument to the operator. As described above, the robot system 1 according to the present embodiment has a function of detecting the force acting on the medical instrument and feeding back the force to the operator. This can contribute to the realization of minimally invasive treatment under an endoscope.

FIG. 2 shows a configuration example of a parallel link device 200 used as a support arm device in at least one of the master device 10 and the slave device 20.

The illustrated parallel link apparatus 200 is a delta parallel link composed of three link units 210, 220, and 230, and has a triaxial translational structure. Each link portion 210, 220, 230 is rotatably coupled to the fixing portion 240. The fixing unit 240 is equipped with actuator units 211, 221, and 231 configured of servomotors and the like, which drive connection portions with the link units 210, 220, and 230, respectively. In addition, the movable portion 250 is supported at the distal end of each link portion 210, 220, 230. The movable portions 250 move relative to the fixed portion 240 in a three-dimensional space by driving the link portions 210, 220, and 230 by the actuator portions 211, 221, and 231, respectively. In addition, although illustration is abbreviate | omitted in FIG. 2, surgical tools, such as forceps, forceps, a cutting instrument, an endoscope, a microscope, a catheter system, are attached to the movable part 250. As shown in FIG.

In this embodiment, each of the actuator units 211, 221, and 231 has an servo motor, an encoder for measuring a rotation angle of an output shaft of the motor, a torque sensor for detecting a torque acting on the output shaft of the motor, and an output of the motor The main feature lies in the integrated construction of a brake for braking the rotation of the shaft. However, the detailed configuration of the actuator units 211, 221, and 231 will be described later.

The link portions 210, 220, and 230 are arranged at intervals of approximately 120 degrees with reference to the center point 241 set on the mounting surface of the fixing portion 240. Therefore, the parallel link device 20 forms a substantially symmetrical shape with respect to the axis 242 passing through the center point 241 so as to be orthogonal to the mounting surface of the fixed portion 240.

Each link unit 210, 220, 230 includes a drive link 212, 222, 232 and a pair of passive links 213, 223, 233, respectively. The drive links 212, 222, 232 extend radially outward extending radially from a center point 241 on the fixed portion 240. Further, one end of each of the drive links 211, 221, 231 is connected to the output shaft of the actuator portion 211, 221, 231, respectively. And each link part 210, 220, 230 is rotatable in the vertical plane containing axis 242 (above-mentioned) centering on the output axis of actuator part 211, 221, 231, respectively.

One end of a pair of passive links 213, 223, 233 is rotatably connected to the other end of the drive links 212, 222, 232. Also, as described above, the movable portion 250 is attached to the other end (distal end) of the pair of passive links 213, 223, 233.

Therefore, by synchronously rotating the three actuator units 211, 221, 231, the drive links 212, 222, 232 and the passive links 213, 223, 233 rotate within their respective vertical planes, and As a result, the movable portion 250 connected to the distal end of each link portion 210, 220, 230 is moved vertically and horizontally to move the movable portion 250 (or an end effector such as a forceps attached to the movable portion 250) Can be displaced to any position in three-dimensional space.

When the parallel link device 200 is used on the master device 10 side, for example, the input unit 11 is attached to the movable unit 250. The user can hold the input unit 11 including an input mechanism such as a lever or a grip and displace it to any position in the three-dimensional space. The driving links 212, 222, and 232 of the link units 210, 220, and 230 are generated by the encoders incorporated in the actuator units 211, 221, and 231 that drive the connection between the fixing unit 240 and the link units 210, 220, and 230. The rotation angle of the movable portion 250 or the position of the movable portion 250 or the input portion 11 in three-dimensional space can be derived. A signal indicating the rotation angle of the drive links 212, 222, 232 is transmitted to the control device 30 as information indicating an instruction for displacing the end effector (surgical instrument) on the slave device 20 side.

Further, by driving each of the actuator units 211, 221, and 231, a translational force can be presented to the user operating the input unit 11 attached to the movable unit 250. For example, when a force acting on the surgical instrument is detected by the state detection unit 22 (torque sensor) when displacing the surgical instrument on the slave device 20 side, each actuator section 211 according to the control amount calculated according to the acting force. , 221, 231 can present the user with translational forces acting on the tool.

On the other hand, when the parallel link device 200 is used on the slave device 10 side, for example, surgical instruments such as an endoscope, a microscope, a catheter system, forceps, forceps, and a cutting tool are attached to the movable portion 250. By driving each of the actuator units 211, 221, and 231 in accordance with the control amount calculated according to the information instructing the displacement of the surgical instrument from the control device 30, the user on the master device 10 side operates on the movable unit 250 as instructed. The surgical tool can be displaced.

Also, when displacing the surgical tool on the slave device 20 side, the torque applied to each link unit 210, 220, 230 is detected based on the detection result by each torque sensor built in the actuator units 211, 221, 231. Furthermore, it is possible to derive an external force applied to the surgical instrument through a predetermined matrix operation. The detection signal of each torque sensor is transmitted to the control device 30 as information indicating an instruction for presenting the user with the translational force acting on the surgical instrument on the master device 10 side.

The parallel link device 200 according to the present embodiment is mainly characterized in that actuator units 211, 221, 231 having an encoder, a torque sensor, and a brake are mounted for driving each link unit 210, 220, 230. There is a feature. This has the advantage that the position and orientation of the robot can be obtained without attaching an external sensor to the link mechanism or other parts. In addition, the parallel link device 200 can also obtain an advantage that external force can be measured without attaching a force sensor or a torque sensor to an end effector or another part.

In terms of mechanism, the parallel link device 200 can reduce the mass and inertia of the entire robot, and can improve control performance. In the present embodiment, virtual inertia can be further reduced according to the torque measurement value by utilizing the fact that each of the actuator units 211, 221, and 231 incorporates a torque sensor. When performing direct teaching on the parallel link device 200, it is possible to give the user the impression of a robot that is apparently lightweight and has low inertia. In addition, it is possible to compensate for the weight of each link unit 210, 220, 230, etc. according to the torque measurement value.

In addition, when an abnormal value of the rotation angle or torque is detected in at least one of the actuator units 211, 221, 231, safety can be ensured by braking the rotation of the output shaft of the motor by the built-in brake. it can.

For example, the control device 30 can input detection signals of the encoders and torque sensors of the respective actuator units 211, 221, 231 from the master device 10 or the slave device 20, and detect an abnormal value of the rotation angle or torque. Alternatively, the control device 30 may detect an abnormality that has occurred in the master device 10 or the slave device 20 using other means. Of course, the abnormality may be detected when the emergency stop button provided on the master device 10 or the slave device 20 is pressed by the user. In any case, the control device 30 can ensure safety by outputting a control signal for operating the brakes of the actuator units 211, 221, 231 to at least one of the master device 10 and the slave device 20. .

FIG. 11 shows, in the form of a flowchart, a schematic processing procedure for stopping the operation of parallel link device 200 in accordance with abnormality detection in robot system 1 using parallel link device 200.

In the control device 30, predetermined abnormality detection processing is performed (step S1201), and it is checked whether or not an abnormality has occurred on the robot system 1 (step S1202).

The control device 30 inputs detection signals of the encoders and torque sensors of the respective actuator units 211, 221, 231 from the master device 10 or the slave device 20 as abnormality detection processing, and detects an abnormal value of the rotation angle or torque. Can. Alternatively, the control device 30 may detect an abnormality that has occurred in the master device 10 or the slave device 20 using other means. Of course, the abnormality may be detected when the emergency stop button provided on the master device 10 or the slave device 20 is pressed by the user.

Then, when an abnormality is detected in at least one of the master device 10 and the slave device 20, the control device 30 performs control to operate the brakes of the actuator units 211, 221, 231 for one or both of the corresponding devices. A signal is output (step S1203). As a result, at least one of the master device 10 and the slave device 20 can stop its operation to ensure safety.

The stopping operation according to the abnormality detection as shown in FIG. 11 is not performed by the control device 30 outside the actuator units 211, 221, 231 (or the parallel link device 200), but individual actuator units It is also possible to configure so as to be executed by the control unit inside 211, 221, 231 (or the control unit mounted on the parallel link device 200).

The mechanism which measures external force in parallel link device 200 concerning this embodiment is explained. It is assumed that torques τ1, τ2, and τ3 are detected from torque sensors built in the actuator units 211, 221, and 231 for driving the link units 210, 220, and 230, respectively. Then, the torques τ1, τ2, and τ3 can be converted into external forces Fx, Fy, and Fz in three directions by matrix calculation as shown in the following equation (1).

That is, from the torque value detected by the torque sensor incorporated in each of the actuator units 211, 221, 231, even if an external force is applied to any part of the parallel link device 200, the external force can be measured. For example, when direct teaching is performed on the parallel link apparatus 200, any part of the link sections 210, 220, 230 other than the end effector can be grasped and operated, which is convenient.

Since the operation by the end effector attached to the movable portion 250 is performed when using the normal parallel link device 200, the external force applied to the end effector is calculated based on the torque measurement value in each of the actuator portions 211, 221, 231. It will be. Of course, even when an external force is applied to a site other than the end effector, the external force can be measured similarly.

In order to measure the external force applied to the end effector, there are also many robot devices in which a force sensor is disposed on an end effector such as a surgical instrument (see, for example, Patent Document 2). However, this type of robot apparatus can not measure an external force applied to a site where no force sensor is provided, such as an arm unit, and thus may cause a dangerous situation during work. On the other hand, the parallel link device 200 according to the present embodiment is configured to measure the external force in the entire device using the actuator units 211, 221, and 231 with built-in torque sensor for driving each link unit. Therefore, it is possible to measure even when an unexpected large external force or disturbance is applied. That is, according to the parallel link apparatus 200 which concerns on this embodiment, the unexpected external force added to arbitrary site | parts is detected, and a safe force control system can be constructed | assembled.

Further, in the parallel link device 200 according to the present embodiment, since each of the actuator units 211, 221, and 231 has a built-in brake, the emergency condition such as when an unexpected large external force is applied is described above. Thus, it is possible to activate the brake and immediately stop its operation.

Note that as a modification of the parallel link device 200, the force sensor 251 may be additionally provided to the movable portion 250 (or the end effector). By combining the torque measurement value of the torque sensor built in each actuator unit 211, 221, 231 with the force detection value by the force sensor 251, the external force applied to each link unit 210, 220, 230 is linked to the link unit 210, 220 , 230 can be estimated. For example, external forces F1, F2, and F3 applied to the link units 210, 220, and 230 are estimated by comparing the force detection value of the force sensor 251 with the torque measurement value of each of the actuator units 211, 221, and 231. It is possible to estimate in more detail the site to which the external force is applied.

The parallel link device 200 shown in FIG. 2 can be applied to both the master device 10 and the slave device 20 to construct a bilateral system. Bilateral control is a control method of operating the slave from the master at the same time in control of the master-slave system and feeding back the state of the slave to the master, and can present power to the user operating the master device 10.

According to this embodiment, the movable portion 250, that is, the three-dimensional end effector, is detected based on the rotation angle detected by the encoder incorporated in the actuator portions 211, 221, 231 for driving the link portions 210, 220, 230. Position information can be measured. At the same time, it is possible to detect the external force applied to the movable portion 250, that is, the end effector, based on each torque value detected by the torque sensor incorporated in the actuator portions 211, 221, 231. In the robot system 1 driven by the bilateral control system, the control device 30 intervenes to transmit information on the position and force of the end effector between the master device 10 and the slave device 20. Then, on the master device 10 side, it is possible to present the user with a feeling of the external environment on the slave device 20 side. Therefore, the robot system 1 driven by the bilateral control system can be applied to medical applications such as remote palpation and surgery, care, and the like.

The parallel link device to which the technology disclosed in this specification can be applied is not limited to the configuration shown in FIG. For example, the technology disclosed in the present specification can be applied to a parallel link device provided with two or more link parts, for example.

Moreover, although illustration is abbreviate | omitted, the technique disclosed by this specification is applicable similarly also to the parallel link apparatus of various installation systems, such as floor standing, wall hanging, ceiling hanging, and shelf placement. In the case of using a parallel link device 200 as a user interface on the master device 10 side in a master-slave system for performing medical applications such as remote palpation and surgery, and nursing care, as shown in FIG. "Horizontal mounting" in which the part 250 is arranged in the horizontal direction, and "vertical mounting" in which the fixed part 240 is installed on the floor and the movable part 250 is arranged substantially vertically upward of the fixed part 240 Is considered suitable.

FIGS. 3 to 6 show configuration examples of the actuator device 300 that can be applied to the drive of the link portions 210, 220, 230 of the parallel link device 200. FIG. However, FIG. 3 is a view showing a cross section of the actuator device 300. More specifically, a cross section cut through a plane passing through a central axis X of the motor shaft 326 described later and orthogonal to the axial direction of the motor shaft 326. FIG. 4 is an exploded perspective view of the actuator device 300. As shown in FIG. 5 is an enlarged view of components on the input side of the actuator device 300, and FIG. 6 is an enlarged view of components on the output side of the actuator device 300. As shown in FIG.

Here, the input side of the actuator device 300 is the side opposite to the side where the wave gear reducer 310 is located with respect to the motor 320 (on the right side of the drawing in the example shown in FIG. 3). Further, the output side of the actuator device 300 is the side where the wave gear reducer 310 is positioned with respect to the motor 320 (left side in the example of FIG. 3). The central axis X may be identical to the central axis of the actuator device 300.

As shown in FIGS. 3 and 4, the actuator device 300 includes a housing 390, a wave gear reducer 310, a motor 320, a brake 330, an input encoder 340 and an output encoder 350, a torque sensor 360, and an input. A side cover 370 and an output side cover 372 are provided. For example, the respective configurations of the input cover 370, the input encoder 340, the brake 330, the motor 320, the wave gear reducer 310, the output encoder 350, the torque sensor 360, and the output cover 372 in the axial direction of the motor shaft 326 An element is disposed within the housing 390.

The motor 320 has a cylindrical rotor (rotator) 324. The wave gear reducer 310 has a wave generator 404 coaxial with the motor shaft 326, and is included in the rotor 324. In other words, the motor 320 and the wave gear reducer 310 are nested. According to such a configuration, the actuator device 300 can be miniaturized by efficiently arranging the wave gear reducer 310 and the motor 320 in the axial direction of the motor shaft 326. In addition, since the motor 320 having a larger size can be disposed with respect to the volume of the actuator device 300, or the rotation radius of the motor 320 can be made larger, the actuator device 300 can be compact while achieving high output. Is possible.

The motor 320 is rotated by being energized to generate rotational torque. In addition, the wave gear reducer 310 reduces the rotational torque output from the motor 320 and outputs the reduced rotational torque to the torque sensor 360. The torque sensor 360 measures the rotational torque transmitted from the wave gear reducer 310. When an external component (not shown) is coupled to the torque sensor 360, the torque sensor 360 outputs a rotational torque to the external component.

The housing 390 supports the wave gear reducer 310, the stator (stator) 322 of the motor 320, and the like in its inside. The housing 390 may have a cylindrical shape, but is not limited to a specific shape, and may be a prism (such as a square prism).

The wave gear reducer 310 has, for example, a cylindrical shape. Also, the wave generator 404 and the output shaft 312 included in the wave gear reducer 310 may be coaxial with the motor shaft 326, respectively.

The output shaft 312 is configured by combining a flexspline 402 and a bracket 420 which will be described later. In the example shown in FIG. 3, in the opening 422 provided in the bracket 420, a part of the flexspline 402 and the bracket 420 are firmly fastened by a spring pin or the like. However, the output shaft 312 may be only the flexspline 402 or only the bracket 420.

Further, in the example shown in FIGS. 3 and 4, the wave gear reducer 310 is configured by a combination of the circular spline 400, the flex spline 402, and the wave generator 404. Specifically, the circular spline 400, the flex spline 402, and the wave generator 404 are disposed in this order from the outside to the inside of the wave gear reducer 310.

The circular spline 400 has a cylindrical first outer circumferential surface 1300 contained in the rotor 324 and a cylindrical second outer circumferential surface 1302 larger in diameter than the first outer circumferential surface 1300. The second outer circumferential surface 1302 is fixed or supported to the inner wall of the housing 390. Also, the circular spline 400 further includes at least one other outer circumferential surface 1304 adjacent to the first outer circumferential surface 1300 and the second outer circumferential surface 1302.

Further, teeth (hereinafter, also referred to as “inner circumferential teeth”) are engraved on the inner periphery of the circular spline 400. The pitch of the inner peripheral teeth is the same as the pitch of teeth (hereinafter, also referred to as “peripheral teeth”) engraved on the outer periphery of the flexspline 402. Further, the number of inner peripheral teeth is larger than the number of outer peripheral teeth of the flexspline 402 by a predetermined number (for example, two). Further, the inner peripheral teeth and the outer peripheral teeth of the flexspline 402 are arranged to mesh with each other.

In addition, a cross roller bearing 314 is fixed to an inner peripheral surface 1306 facing the second outer peripheral surface 1302. Cross roller bearings 314 rotatably support the output shaft 312.

For example, the inner circumferential surface 1306 is fixed to the outer ring 440 of the cross roller bearing 314. More specifically, the outer ring 440 is preloaded by the inner circumferential surface 1306 and the outer lock ring 480. Also, the inner ring 442 of the cross roller bearing 314 is preloaded by the bracket 420 and the inner lock ring 482. By using the cross roller bearing 314 as described above, since it is possible to receive moment loads other than the motor shaft 326, smooth torque transmission can be realized. A ball bearing may be used instead of the cross roller bearing 314.

The flexspline 402 is a cup-shaped metal elastic body. The flexspline 402 is fixed to the wave generator 404. Further, as shown in FIG. 3, a bearing 316 is fixed to the inside (for example, the root inner side) of the flexspline 402. The bearing 316 rotatably supports the motor shaft 326. Further, as shown in FIGS. 3 and 6, the flexspline 402 is screwed to the torque sensor 360 by a screw (eg, a bolt).

As shown in FIGS. 3 and 4, the wave generator 404 is configured by combining an elliptical portion 406 and a bearing 408. The elliptical portion 406 has an elliptical shape. In addition, the oval portion 406 is fixed to the rotor 324, the motor shaft 326, and the flexspline 402. According to such a configuration, when the rotor 324 of the motor 320 rotates, the wave generator 404 rotates in synchronization with the rotor 324. The flexspline 402 fixed to the wave generator 404 bends in an elliptical shape according to the rotation of the wave generator 404 (while being elastically deformed), and the inner peripheral teeth of the circular spline 400 and the outer peripheral teeth of the flexspline 402 It rotates in the state engaged in two places of the major axis direction of the said ellipse. Thereby, the flexspline 402 decelerates and rotates with respect to the wave generator 404. Then, the output shaft 312 rotates at the speed decelerated in this manner. Furthermore, a torque corresponding to the rotation of the output shaft 312 is transmitted to the torque sensor 360 via the output shaft 312.

The motor 320 is rotated by being energized to generate rotational torque. The motor 320 is configured by, for example, a brushless motor. Further, as shown in FIGS. 3 and 4, the motor 320 includes a stator 322, a rotor 324, and a motor shaft 326. The combination of the stator 322 and the rotor 324 constitutes a motor magnetic circuit. For example, when a three-phase alternating current is supplied to the stator 322, the motor 320 generates a rotational torque by generating a rotating magnetic field between the stator 322 and the plurality of motor magnets 542 included in the rotor 324. .

As shown in FIG. 3, the stator 322 is fixed to the inner wall of the housing 390. Also, as shown in FIG. 3 and FIG. 4, the stator 322 includes a stack core 520 and a motor coil 522. For example, the outer peripheral surface of the stack core 520 is fixed to the inner wall of the housing 390. Motor coil 522 is fixed to the inner circumferential surface of stack core 520.

The rotor 324 has a cylindrical shape and is disposed so as to enclose the first outer circumferential surface 1300 of the circular spline 400. The rotor 324 also includes a motor yoke 540 and a plurality of motor magnets 542. For example, as shown in FIGS. 3 and 5, the motor yoke 540 is provided with a support 2720 including a surface orthogonal to the extending direction of the rotor 324 and supporting the motor shaft 326. For example, the support portion 2720 is fixed to the wave generator 404.

The motor magnet 542 may be a permanent magnet. Further, as shown in FIGS. 4 and 5, a plurality of motor magnets 542 are disposed on the outer peripheral surface of the motor yoke 540 at equal intervals, for example. Here, the number of poles of the plurality of motor magnets 542 is, for example, eight or more. The cogging torque decreases as the number of poles increases, which is preferable.

According to the above configuration, the motor magnet 542 having a larger size can be disposed in the housing 390 without changing the structure of the wave gear reducer 310. In addition, since it is also possible to employ | adopt the motor magnet 542 of a different size for every scene which applies the actuator apparatus 300, various motor outputs are realizable. Although not directly related to the present embodiment, in the robot arm of the serial link structure, the holding torque required is also different because the weight is different for each joint. According to the structure of the actuator device 300 shown in FIG. 3 to FIG. 6, an appropriate output is realized for each joint by appropriately changing the motor magnetic circuit unit (for example, the size of the motor and magnet 542) for each joint. be able to.

The motor shaft 326 is a rotating shaft of the motor 320. As shown in FIG. 3, the motor shaft 326 is rotatably supported around the central axis X by a bearing 316 and a bearing 338 described later. As described above, the bearing 316 is installed inside the base of the flexspline 402. That is, the distance between the two bearings (bearing 316 and bearing 338) supporting the motor shaft 326 is large. Thereby, for example, the swing of the motor shaft 326 at the time of driving the motor 320 can be suppressed. Further, since the bearing 316 and the bearing 338 are respectively installed in the empty space, the actuator device 300 can be further miniaturized.

Also, the motor shaft 326 may have a hollow structure. As shown in FIGS. 3 and 4, a hollow tube 380 can be disposed inside the motor shaft 326.

The brake 330 is a mechanism for stopping the rotation of the rotor 324. The brake 330 may be a non-excitation type brake. Further, the brake 330 is disposed on the opposite side of the wave gear reducer 310 with respect to the motor 320. That is, the brake 330 is disposed at a position before deceleration by the wave gear reducer 310. According to such a configuration, the brake torque required to stop the rotation of the rotor 324 can be reduced by the reduction ratio of the wave gear reducer 310.

The configuration of the brake 330 is described in further detail below. The brake 330 includes a main body portion 332, a rotation portion 334, a mover 336, and an elastic member (not shown).

The rotation unit 334 is disposed farther than the main body 332 with reference to the position of the motor 320. In addition, the rotating unit 334 is coaxial with the motor shaft 326 and is fixed to the wave generator 404. For example, the rotating unit 334 is fixed to one end of the wave generator 404 and rotates in synchronization with the rotor 324. Further, as described later, an input encoder disk 344 is fixed to the rotating portion 334. According to such a configuration, when the coaxiality of the rotor 324, the rotation shaft of the wave gear reducer 310, and the brake 330 is set with high accuracy, the accuracy of measurement by the input encoder 340 can be enhanced, and it is smooth. Torque transmission can be realized.

The mover 336 is made of an armature or the like, and is disposed in the gap between the main body 332 and the rotating portion 334.

The elastic member is, for example, a compression coil spring, is fixed to the main body portion 332 and the mover 336, and is configured to apply an elastic force toward the rotating portion 334 to the mover 336. For example, when the electromagnet 620 described later is not energized, the mover 336 is pressed against the rotating portion 334 by the elastic member. As a result, due to the friction of the contact surface between the rotating portion 334 and the mover 336, a friction torque serving as a brake torque is generated, and the rotation of the rotating portion 334 is stopped. As a result, the rotation of the rotor 324 connected to the rotating unit 334 via, for example, the wave generator 404 is stopped.

As shown in FIG. 4, an electromagnet 620 is fixed to the main body 332. The electromagnet 620 draws the mover 336 to the main body 332 in accordance with the current flow. For example, the electromagnet 620 at the time of energization draws the mover 336 to the main body portion 332, thereby releasing the brake torque, so that the rotating portion 334 becomes rotatable. As a result, the rotor 324 also becomes rotatable. On the other hand, since the electromagnet 620 does not draw the mover 336 to the main body 332 when the current is not supplied, the brake torque is not released, the rotating portion 334 can not rotate, and the rotor 324 can not rotate.

Further, as shown in FIG. 3, a bearing 338 is fixed substantially at the center of the main body 332. The bearing 338 rotatably supports the motor shaft 326.

Further, the main body portion 332 supports the wave gear reducer 310 by being disposed to be pressed against the side surface of the wave gear reducer 310. Further, as shown in FIG. 3, the housing 390 and the main body portion 332 are fixed in an inlay structure. Thereby, the coaxiality of the rotor 324, the rotation shaft of the wave gear reducer 310, and the brake 330 can be easily increased.

The input encoder 340 is disposed on the input side of the actuator device 300 to measure the rotation angle of the rotor 324. For example, the input encoder 340 is an absolute encoder that measures the absolute angle of the rotor 324. Thus, for example, the control device 30 that controls the actuator device 300 can change the output of the motor 320 in real time based on the measurement result of the rotation angle of the rotor 324 by the input encoder 340.

Further, as shown in FIG. 4, the input encoder 340 includes an input encoder substrate 342 and a disk-shaped input encoder disc 344. Hereinafter, the configuration of the input encoder 340 will be described in more detail with reference to FIGS. 7 and 8. However, FIG. 7 is an enlarged view of the area 304 shown in FIG. 8 is a view schematically showing a cross section taken along the line AA shown in FIG.

As shown in FIG. 7, a magnetic field measurement element 720 is mounted on the input encoder substrate 342. For example, as shown in FIG. 8, the magnetic field measurement element 720 is configured by combining a permanent magnet 4500 and a Hall element (Integrated Circuit) 4202.

As shown in FIG. 4, the input encoder holder 724 is fixed to the input encoder substrate 342. The input encoder holder 724 and the input encoder bracket 722 fixed to the main body 332 of the brake 330 are fixed by, for example, an inlay structure. The input encoder bracket 722 is fixed to the main body 332 by, for example, a jig so as to be coaxial with the main body 332 of the brake 330.

The input encoder disk 344 is, for example, a magnetic disk in which a plurality of slits (openings) having a predetermined pattern are formed. Further, as shown in FIG. 5, the input encoder disk 344 is fixed to the rotating portion 334 of the brake 330. According to such a configuration, when the input encoder disk 344 rotates in response to the rotation of the rotating portion 334, the input encoder disk (slit is formed) for the biased magnetic field generated by the permanent magnet 4500. As the 344 traverses, the flux density changes. The magnetic flux density measured by the magnetic field measurement element 720 (more specifically, the Hall IC 4502) changes. Therefore, based on the change of the magnetic flux density measured by the magnetic field measurement element 720, the absolute rotation angle of the rotor 324 can be measured.

The output encoder 350 is disposed on the output side of the actuator device 300 and measures the rotation angle of the output shaft 312. The output encoder 350 is disposed, for example, between the torque sensor 360 and the housing 390. The output encoder 350 is an absolute encoder that measures the absolute rotation angle of the output shaft 312. As shown in FIG. 4, the output encoder 350 is composed of an output encoder board 352 and a disk-shaped output encoder disc 354.

A magnetic field measurement element 820 is mounted on the output encoder substrate 352. The magnetic field measurement element 820 is configured, for example, by combining a permanent magnet and a Hall element. The magnetic field measuring element 820 may be the same element as the magnetic field measuring element 720 (described above) mounted on the input encoder substrate 342. For example, as shown in FIG. 6, an output substrate holder 926 is attached to the output encoder substrate 352. The output substrate holder 926 and a torque sensor distortion body 362, which will be described later, are fixed by, for example, an inlay structure.

The output encoder disk 354 is, for example, a magnetic disk in which a plurality of slits (openings) having a predetermined pattern are formed. The output encoder disc 354 may be the same disc as the input encoder disc 344 described above.

As shown in FIG. 3, the output encoder disk 354 is fixed to a housing 390 (eg, a groove formed in the housing 390). According to such a configuration, in accordance with the rotation of the output shaft 312 of the wave gear reducer 310, the torque sensor distortion body 362 rotates. Then, by rotating the output encoder substrate 352 in accordance with the rotation of the torque sensor distortion body 362, a slit is formed for the biased magnetic field generated by the permanent magnet (included in the magnetic field measurement element 820). The flux density changes as the output encoder disk 354 relatively traverses. Therefore, based on the change of the magnetic flux density measured by the magnetic field measuring element 820, the absolute rotation angle of the output shaft 312 can be measured.

Although the above describes the configuration example in which both the input encoder 340 and the output encoder 350 are magnetic encoders, the application scope of the technology disclosed in the present specification is not limited to this. For example, at least one of the input encoder 340 and the output encoder 350 may be an optical encoder.

The torque sensor 360 is fixed to the output shaft 312 of the wave gear reducer 310, and measures a torque according to the rotation of the output shaft 312. Further, the torque sensor 360 includes a torque sensor distortion body 362 and a torque sensor substrate 364.

As shown in FIG. 4, the torque sensor strain body 362 has a first rotary body 920 fixed to the output shaft 312, a second rotary body 924, a first rotary body 920 and a second rotation. A plurality of straining portions 922 fixed to a body 924 are provided. When rotational torque is applied to the first rotary body 920, each of the plurality of strain-flexing parts 922 can transmit the rotational torque to the second rotary body 924 while causing distortion, for example.

The torque sensor substrate 364 measures the rotational torque in accordance with the detection result of the strain generated in each of the plurality of strain generating portions 922. For example, strain gauges (not shown) are attached to each of the plurality of strain generating portions 922, and each strain gauge detects strain generated in the strain generating portion 922. Then, the torque sensor substrate 364 measures the input rotational torque based on the detection result of the other strain possessed by each strain generating unit 922.

The external force applied to the torque sensor 360 is transmitted to the inside (the wave gear reducer 310 or the like) of the actuator device 300 via the strain generating portion 922. Therefore, the torque sensor substrate 364 can accurately measure the torque corresponding to the external force according to the detection result of the strain generated in the strain generating portion 922. In addition, the measurement result by the torque sensor 360 is transmitted to the control device 30 outside the actuator device 300 via a cable (for example, coaxial cable) 382 connected to the torque sensor 360 and inserted into the hollow tube 380. Can. In this case, control device 30 can appropriately control (feedback control) the value of the three-phase alternating current supplied to stator 322 in accordance with the received measurement result. By this, the actuator device 300 can output a target torque even when receiving an external force.

The strain gauge used for the torque sensor 360 may be, for example, any of a magnetostrictive type, a capacitive type, a semiconductor strain gauge type, or a general-purpose strain gauge type.

The hollow tube 380 is disposed inside the motor shaft 326, and its both ends are supported by the input side cover 370 and the output side cover 372. For example, the hollow tube 380 may be supported by bearings (not shown) provided on the input side cover 370 and the output side cover 372, respectively. The input side cover 370 and the output side cover 372 are respectively formed using a resin material with small sliding resistance such as polyacetal (POM) resin. The hollow tube 380 may also be made of metal. In this case, since the friction generated when the input cover 370 and the output cover 372 support the hollow tube 380 is extremely small, the same effect as the bearing can be realized. Further, the actuator device 300 can be further miniaturized in the axial direction of the motor shaft 326.

The cable 382 can be inserted into the hollow tube 380. For example, a cable connecting the input encoder 340 and the output encoder 350, and a cable connecting each of the input encoder 340, the output encoder 350, and the torque sensor 360 to an external device (for example, the control device 30). And so on. As an example, at least one power supply line for supplying power to input encoder 340, output encoder 350, and torque sensor 360 is inserted into hollow tube 380. In addition, at least one signal line for transmitting a signal between each of the input encoder 340, the output encoder 350, and the torque sensor 360 and an external device (for example, the control device 30) is inserted into the hollow tube 380. Be done.

The inside of the motor shaft 326 has the smallest rotation radius in the actuator device 300, and no other components exist inside the motor shaft 326. Therefore, as described above, by disposing the hollow tube 380 inside the motor shaft 326, the wiring structure can be simplified, and multiple rotations of the motor 320 can be realized. For example, the clearance within the motor shaft 326 can be kept constant. Further, since the motor shaft 326 and the cable 382 do not come in contact with each other, useless friction torque is not generated inside the actuator device 300. Also, for example, each of the input encoder 340, the output encoder 350, and the torque sensor 360 can be connected to the control device 30 with one cable.

Here, the features of the actuator device 300 applied to the parallel link device 200 according to the present embodiment will be summarized.

The actuator device 300 includes a motor 320 having a cylindrical rotor 324 and a wave gear reducer 310 incorporated in the rotor 324, and can realize a small size and high output. The actuator device 300 can arrange the motor 320 (e.g., the motor magnet 542 or the like) of a larger size with respect to the volume, and the rotation radius of the motor 320 becomes larger. Therefore, since the generated magnetic flux density is increased, the actuator device 300 can achieve high output even with a small size.

Further, an input encoder 340 and an output encoder 350 are disposed at positions before and after deceleration of the wave gear reducer 310, respectively. By using an absolute encoder for the input encoder 340 and the output encoder 350, the relationship between the absolute angle on the input side of the actuator device 300 and the absolute angle on the output side can always be measured. For example, even if the actuator is moved due to an external force applied to the output side of the actuator device 300 while the power is stopped, the relationship between the absolute angle on the input side and the absolute angle on the output side at power on. Can be grasped immediately. Therefore, the home position return operation at the time of power on becomes unnecessary.

Further, a torque sensor 360 is disposed on the output shaft 312 of the wave gear reducer 310. Therefore, the output torque can be measured in real time. When the actuator device 300 is mounted for driving the link portion of the parallel link device 200 as shown in FIG. 2, it becomes possible to give a torque command while detecting the external force applied to the movable portion 250. In addition, when such a parallel link device 200 is used as a support arm device of the master device 10 or the slave device 20 in the robot system 1 of a master-slave system for medical use, it contributes to the realization of a minimally invasive procedure. can do.

The actuator device 300 also includes a non-excitation type brake 330 or the like. Therefore, when an abnormality occurs, by stopping the output of the actuator device 300, the operation of the parallel link device 200 is also stopped, and safety can be ensured. For example, when an abnormality is detected based on detection signals of the input encoder 340 or the output encoder 350 and the torque sensor 360, the output of the actuator device 300 can be stopped to ensure safety.

In addition, since the actuator device 300 includes all the component parts such as the motor, the encoder, the torque sensor, and the brake in the housing 390 so as to be unitized, the actuator device 300 is not limited to the parallel link device 200 shown in FIG. It is easy to install it on various robot devices.

FIGS. 9 and 10 show the configuration of an actuator device 1000 according to a modification of the actuator device 300 described above. However, FIG. 9 is a view showing a cross section of the actuator device 300. More specifically, it is cut at a plane that passes through the central axis X of the motor shaft 326 described later and is orthogonal to the axial direction of the motor shaft 326. FIG. 10 is an exploded perspective view of the actuator device 300. FIG. The same components as those of the actuator device 300 are denoted by the same reference numerals.

The actuator device 1000 is characterized mainly in that a wave gear reducer 310 that is larger than the actuator device 300 is disposed to enable higher output. Similarly to the actuator device 300, the actuator device 1000 can also be applied to drive the link portions 210, 220, and 230 of the parallel link device 200.

As can be seen from FIG. 9, a part of the main body 332 of the brake 330 is contained in the rotor 324. For example, the wave gear reducer 310 is included in the rotor 324 on the first side of the rotor 324 with the support portion 2720 as a boundary. Further, on the second side opposite to the first side with the support portion 2720 as a boundary, a part of the main body portion 332 is included in the rotor 324. In other words, the brake 330 and the wave gear reducer 310 are nested. According to such a configuration, the actuator device 1000 can be further miniaturized or thinned in the axial direction of the motor shaft 326.

FIG. 12 schematically shows a control block diagram of the actuator device 300. As shown in FIG. The control unit 1301 is equipped with a wired or wireless communication interface, and can communicate with an external device such as the control device 30.

The control unit 1301 outputs, for example, a control signal (or a current signal) for rotating and driving the motor 1302 in accordance with a control command from the control device 30.

Further, the control unit 1301 processes detection signals of the encoder 1303, the torque sensor 1304, or other sensors (not shown) incorporated in the actuator device 300. Then, the control unit 1301 externally outputs the processing result of the detection signal to the control device 30 (or another external device) through the communication interface.

Furthermore, the control unit 1301 processes a detection signal of the encoder 1303, the torque sensor 1304, or other sensors (not shown) incorporated in the actuator device 300, and executes parallel processing on which the actuator device 300 is mounted. It can be determined whether or not an abnormality has occurred in the link device 200 or the actuator device 300 itself.

When the control unit 1301 determines that an abnormality has occurred in the parallel link device 200 mounting the actuator device 300 or the actuator device 300 itself, the brake 1305 is used to stop the rotation of the motor 1301 urgently. Output a control signal to operate the Further, in order to stop the rotation of the motor 1301 urgently, the control unit 1301 responds to the reception of the stop instruction from the control device 30 (or other external device) via the communication interface. A control signal for operating the brake 1305 is output.

FIG. 13 shows the hardware configuration of an information processing apparatus 2100 that can operate as the control system 30 in the robot system 1 shown in FIG.

The illustrated information processing apparatus 2100 mainly includes a CPU 2101, a ROM (Read Only Memory) 2103, and a RAM (Random Access Memory) 2105, and further, a host bus 2107, a bridge 2109, an external bus 2111, and an interface 2113. , An input device 2115, an output device 2117, a storage device 2119, a drive 2121, a connection port 2123, and a communication device 2125.

The CPU 2101 functions as an arithmetic processing unit and a control unit, and controls the overall operation or a part of the information processing apparatus 2100 according to various programs recorded in the ROM 2103, the RAM 2105, the storage device 2119, or the removable storage medium 2127. The ROM 2103 stores programs and calculation parameters used by the CPU 2101 in a non-volatile manner. The RAM 2105 temporarily stores a program used by the CPU 2101, a parameter that appropriately changes in the execution of the program, and the like. These are mutually connected by a host bus 2107 configured by an internal bus such as a CPU bus. The function of the control system 30 in the robot system 1 shown in FIG. 1 can be realized, for example, by the CPU 2101 executing a predetermined program.

The host bus 2107 is connected to an external bus 2111 such as a peripheral component interconnect (PCI) bus via a bridge 2109. Further, an input device 2115, an output device 2117, a storage device 2119, a drive 2121, a connection port 2123, and a communication device 2125 are connected to the external bus 2111 via an interface 2113.

The input device 2115 is, for example, an operation device operated by the user, such as a mouse, a keyboard, a touch panel, a button, a switch, a lever, and a pedal. Also, the input device 2115 may be, for example, a remote controller (so-called, remote control) using infrared rays or other radio waves, a mobile phone or a smart phone, or a PDA (Personal Digital Assistant) corresponding to the operation of the information processing apparatus 2100. Etc.) may be used. Furthermore, the input device 2115 includes, for example, an input control circuit that generates an input signal based on the information input by the user using the operation device described above, and outputs the generated input signal to the CPU 2101. The user of the information processing device 2100 can input various data to the information processing device 2100 and instruct processing operations by operating the input device 2115.

The output device 2117 is configured of a device capable of visually or aurally notifying the user of the acquired information. Such devices include display devices such as CRT display devices, liquid crystal display devices, plasma display devices, EL display devices and lamps, audio output devices such as speakers and headphones, and printer devices. The output device 2117 outputs, for example, results obtained by various processes performed by the information processing device 2100. Specifically, the display device displays the result obtained by the various processes performed by the information processing device 2100 as text or an image. On the other hand, the audio output device converts an audio signal composed of reproduced audio data, acoustic data and the like into an analog signal and outputs it as audio. The monitor 260 provided in the master device 10 can be realized by, for example, the output device 2117.

The storage device 2119 is a device for data storage configured as an example of a storage unit of the information processing device 2100. The storage device 2119 is configured of, for example, a magnetic storage unit device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, a magneto-optical storage device, or the like. The storage device 2119 stores programs executed by the CPU 2101, various data, and the like.

The drive 2121 is a reader / writer for a recording medium, and is built in or externally attached to the information processing apparatus 2100. The drive 2121 reads out information recorded on a removable recording medium 2127 such as a mounted magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and outputs the information to the RAM 2105 or the like. The drive 2121 can also write a record on a removable recording medium 2127 such as a mounted magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory. The removable recording medium 2127 is, for example, a DVD medium, an HD-DVD medium, or a Blu-ray (registered trademark) medium. Also, the removable recording medium 2127 may be a Compact Flash (registered trademark) (CF: Compact Flash), a flash memory, an SD memory card (Secure Digital memory card), or the like. Further, the removable recording medium 2127 may be, for example, an IC (Integrated Circuit) card or an electronic device in which a non-contact IC chip is mounted.

The connection port 2123 is a port for direct connection to the information processing apparatus 2100. Examples of the connection port 2123 include a Universal Serial Bus (USB) port, an IEEE 1394 port, and a Small Computer System Interface (SCSI) port. As another example of the connection port 2123, there are an RS-232C port, an optical audio terminal, a high-definition multimedia interface (HDMI (registered trademark)) port, and the like. By connecting the external connection device 2129 to the connection port 2123, the information processing apparatus 2100 directly acquires various data from the external connection device 2129 or provides various data to the external connection device 2129.

The communication device 2125 is, for example, a communication interface configured of a communication device or the like for connecting to a communication network (network) 2131. The communication device 2125 is, for example, a communication card for a wired or wireless LAN (Local Area Network), Bluetooth (registered trademark) or WUSB (Wireless USB). The communication device 2125 may also be a router for optical communication, a router for Asymmetric Digital Subscriber Line (ADSL), a modem for various types of communication, or the like. The communication device 2125 can transmit and receive transmission signals with the Internet or another communication device according to a predetermined protocol such as TCP / IP. Further, the communication network 2131 connected to the communication device 2125 is configured by a network or the like connected by wire or wireless, and may be, for example, the Internet, home LAN, infrared communication, radio wave communication or satellite communication. .

The example of the hardware configuration of the information processing apparatus 2100 capable of realizing the function of the control system 30 in the robot system 1 according to the present embodiment has been described above. Each of the components described above may be configured using a general-purpose member, or may be configured by hardware specialized for the function of each component. Therefore, it is possible to change the hardware configuration to be used as appropriate according to the technical level at which the present embodiment is implemented. Although not shown in FIG. 13, naturally, various configurations corresponding to the information processing apparatus 2100 configuring the control system 30 according to the present embodiment are provided.

A computer program for realizing the functions of the information processing apparatus 2100 constituting the control system 30 according to the present embodiment as described above can be prepared and implemented on a personal computer or the like. In addition, a computer readable recording medium in which such a computer program is stored can be provided. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory or the like. In addition, the above computer program may be distributed via, for example, a network without using a recording medium. Further, the number of computers that execute the computer program is not particularly limited. For example, a plurality of computers (for example, a plurality of servers) may execute the computer program in cooperation with each other. Note that a single computer or a computer in which a plurality of computers cooperate is also referred to as a “computer system”.

The technology disclosed herein has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiment without departing from the scope of the technology disclosed herein.

The parallel link device disclosed herein can be applied to various industrial fields including the medical field. For example, the parallel link device disclosed herein can be applied to industrial robots such as machine tools. The parallel link device disclosed in the present specification can be applied to various installation methods such as floor mounting, wall mounting, ceiling mounting, shelf mounting, etc., depending on the application and the like. In addition, the technology disclosed herein can be applied to various types of parallel link devices provided with two or more link units.

Further, the parallel link device disclosed in the present specification can be applied to at least one of the master side and the slave side in a master-slave robot system. The master-slave system to which the technology disclosed herein is applied can secure both control performance and safety, and can be applied to medical applications such as remote palpation and surgery, care, and the like.

A master-slave system to which the technology disclosed herein is applied can be driven by various control systems including a bilateral control system and a unilateral control system.

In short, although the technology disclosed herein has been described in the form of exemplification, the contents of the specification should not be interpreted in a limited manner. In order to determine the scope of the technology disclosed herein, the claims should be referred to.

Note that the technology disclosed in the present specification can also be configured as follows.
(1) A fixed unit having a plurality of actuator units, a plurality of link units respectively connected to the fixed unit via the plurality of actuator units, and a movable unit supported by the plurality of link units,
The actuator unit incorporates a motor, an encoder for detecting a rotation angle of an output shaft of the motor, a torque sensor for detecting a torque applied to the output shaft of the motor, and a brake for stopping rotation of the motor.
Parallel link device.
(2) The movable unit is configured to be connectable to a medical unit.
The parallel link device according to (1) above.
(3) The apparatus further comprises a force sensor disposed in the movable portion.
The parallel link device according to any one of the above (1) or (2).
(4) The control apparatus further includes a control unit that controls the operation of the brake.
The parallel link device according to any one of the above (1) to (3).
(5) The control unit controls the operation of the brake based on the detection result of the torque sensor or the encoder.
The parallel link device according to (4) above.
(6) applied to the master side in the master-slave system
The parallel link device according to any one of the above (1) to (5).
(7) Applied to the slave side in the master-slave system
The parallel link device according to any one of the above (1) to (6).
(8) The motor includes a cylindrical rotor and a reduction gear included in the rotor.
The parallel link device according to any one of the above (1) to (7).
(9) The reduction gear is a wave gear reduction gear,
The parallel link device according to (8) above.
(10) The torque sensor is fixed to an output shaft of the reduction gear.
The parallel link device according to any one of the above (8) or (9).
(11) The brake is disposed on the opposite side of the reduction gear to the motor.
The parallel link device according to any one of the above (8) to (10).
(12) The brake is
With the fixed body part,
A rotating unit coaxial with the rotation shaft of the motor;
The parallel link device according to (11) above.
(13) The brake is
A mover disposed between the main body portion and the rotating portion;
An elastic member configured to apply an elastic force toward the rotating portion to the mover, and fixed to the main body portion;
An electromagnet that draws the mover toward the main body when energized;
Further comprising
The parallel link device according to (12) above.
(14) The encoder
A first encoder for measuring a rotation angle of the motor;
And a second encoder for measuring the rotation angle of the reduction gear.
The parallel link device according to any one of the above (8) to (13).
(15) The first encoder is disposed on the side where the brake is located with respect to the motor,
The second encoder is disposed between the torque sensor fixed to the output shaft of the reducer, and a housing supporting the reducer and the stator of the motor.
The parallel link device according to (14) above.
(16) The rotation shaft of the motor is hollow,
The apparatus further comprises a cable inserted into the rotation shaft of the motor.
The parallel link device according to any one of the above (1) to (15).
(17) A master device and a slave device are provided,
At least one of the master device and the slave device has a parallel link device operating with an actuator including a motor, an encoder, a torque sensor, and a brake as a drive source.
Master-slave system.
(18) At least the slave device comprises the parallel link device;
The tip of the parallel link device is configured to be connectable to a medical unit,
The master-slave system according to (17) above.
(19) The master device and the slave device both have the parallel link device,
According to the detection result of the encoder of the actuator of the master device by a bilateral control system, the motor of the actuator of the slave device is driven, and the detection result of the torque sensor of the actuator of the slave device Drive the motor of the actuator on the side of the master device according to
The master-slave system according to any one of the above (17) or (18).
(20) The brake is operated based on the detection result of the torque sensor or the detection result of the encoder to stop driving of the actuator.
The master-slave system according to any one of the above (17) to (19).

DESCRIPTION OF SYMBOLS 1 ... Robot system 10 ... Master apparatus, 11 ... Input part, 12 ... Force presentation part 20 ... Slave apparatus, 21 ... Drive part, 22 ... State detection part 30 ... Control system 200 ... Parallel link apparatus 210 ... Link part, 211 ... Actuator section 212 ... Drive link, 213 ... Passive link 220 ... Link section, 221 ... Actuator section 222 ... Drive link, 223 ... Passive link 230 ... Link section, 231 ... Actuator section 232 ... Drive link, 233 ... Passive link 240 ... Fixed part, 250 ... movable part, 251 ... Force sensor 2100 ... Information processing device, 2101 ... CPU, 2103 ... ROM
2105 ... RAM, 2107 ... host bus, 2109 ... bridge 2111 ... external bus, 2113 interface, 2115 ... input device 2117 ... output device, 2119 ... storage device, 2121 ... drive 2123 ... connection port, 2125 ... communication device

Claims (20)

A fixed part having a plurality of actuator parts, a plurality of link parts respectively connected to the fixed part via the plurality of actuator parts, and a movable part supported by the plurality of link parts,
The actuator unit incorporates a motor, an encoder for detecting a rotation angle of an output shaft of the motor, a torque sensor for detecting a torque applied to the output shaft of the motor, and a brake for stopping rotation of the motor.
Parallel link device. The movable portion is configured to be connectable to a medical unit.
The parallel link device according to claim 1. It further comprises a force sensor disposed on the movable part,
The parallel link device according to claim 1. The controller further includes a control unit that controls the operation of the brake.
The parallel link device according to claim 1. The control unit controls the operation of the brake based on a detection result of the torque sensor or the encoder.
The parallel link device according to claim 4. Applied to the master side in the master-slave system,
The parallel link device according to claim 1. Applied to the slave side in a master-slave system,
The parallel link device according to claim 1. The motor includes a cylindrical rotor and a reduction gear included in the rotor.
The parallel link device according to claim 1. The reduction gear is a wave gear reduction gear,
The parallel link device according to claim 8. The torque sensor is fixed to an output shaft of the reduction gear.
The parallel link device according to claim 8. The brake is disposed on the opposite side of the reduction gear to the motor.
The parallel link device according to claim 8. The brake is
With the fixed body part,
A rotating unit coaxial with the rotation shaft of the motor;
The parallel link device according to claim 11. The brake is
A mover disposed between the main body portion and the rotating portion;
An elastic member configured to apply an elastic force toward the rotating portion to the mover, and fixed to the main body portion;
An electromagnet that draws the mover toward the main body when energized;
Further comprising
The parallel link device according to claim 12. The encoder
A first encoder for measuring a rotation angle of the motor;
And a second encoder for measuring the rotation angle of the reduction gear.
The parallel link device according to claim 8. The first encoder is disposed on the side where the brake is located with respect to the motor,
The second encoder is disposed between the torque sensor fixed to the output shaft of the reducer, and a housing supporting the reducer and the stator of the motor.
The parallel link device according to claim 14. The rotating shaft of the motor is hollow,
The apparatus further comprises a cable inserted into the rotation shaft of the motor.
The parallel link device according to claim 1. It has a master device and a slave device,
At least one of the master device and the slave device has a parallel link device operating with an actuator including a motor, an encoder, a torque sensor, and a brake as a drive source.
Master-slave system. At least the slave device comprises the parallel link device,
The tip of the parallel link device is configured to be connectable to a medical unit,
A master-slave system according to claim 17. Both the master device and the slave device have the parallel link device,
According to the detection result of the encoder of the actuator of the master device by a bilateral control system, the motor of the actuator of the slave device is driven, and the detection result of the torque sensor of the actuator of the slave device Drive the motor of the actuator on the side of the master device according to
A master-slave system according to claim 17. The brake is operated based on the detection result of the torque sensor or the detection result of the encoder to stop driving of the actuator.
A master-slave system according to claim 17.

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