JP5500921B2 - Multi-finger hand device - Google Patents

Description

  The present invention relates to a multi-finger hand device including at least three finger mechanisms.

  In recent years, multi-fingered hand devices that imitate human hands are known. This type of multi-finger hand device includes a base and a plurality of finger mechanisms. Each finger mechanism is provided with a plurality of joints and is rotatable for each joint, thereby enabling bending and stretching operations (see, for example, Patent Document 1).

  By the way, this type of multi-finger hand device has a thumb mechanism corresponding to the thumb of a human hand, but it is necessary to have a configuration different from other finger mechanisms in order to perform an operation close to the movement of a human thumb. There is.

  Specifically, the human thumb is positioned on the side lined up with other fingers when the hand is opened by the carpal joint, and rotates to the side facing the palm when gripping an object. In order to perform this operation in the multi-finger hand device, the thumb mechanism requires a rotation shaft having an axis in a direction different from the joints of the other finger mechanisms. And in the thing of patent document 1, the axis line of the rotating shaft which performs opening operation | movement of a thumb mechanism is located on the extended line of the extended state of a middle finger mechanism.

JP 2008-183629 A

  In a human hand, when picking up a cylindrical object with three fingers, the thumb, index finger, and middle finger, the fingertip of the index finger and the fingertip of the middle finger are brought into contact with one side of the object and vice versa. The fingertip of the thumb is abutted from the side. However, when the same operation is performed by the multi-finger hand device described in Patent Document 1, the finger mechanism of the thumb mechanism from the opposite side of the center position between the fingertip of the pointing mechanism and the fingertip of the middle finger mechanism that is in contact with one side of the object. When the fingertip is about to come into contact, the axis of the rotating shaft that performs the opening operation of the thumb mechanism is positioned on the extended line of the middle finger mechanism, causing an unnecessary moment around the rotating shaft. There is an inconvenience that cannot be gripped stably.

  An object of the present invention is to provide a multi-finger hand device that can realize a stable gripping state of an object using the thumb, index, and middle finger mechanisms.

The present invention includes a base portion and at least three finger mechanisms connected to the base portion, and the three finger mechanisms respectively have a bending mechanism that mimics the movement of the index finger in a human hand, and the movement of the middle finger. A multi-finger hand device having a middle finger mechanism having a simulated bending / extension function and a thumb mechanism having a bending / extension function imitating the movement of a thumb, wherein each of the indicating finger mechanism and the middle finger mechanism is uniaxial , A proximal interphalangeal joint that rotates in one axis about an axis parallel to the rotational axis of the distal interphalangeal joint, and the proximal interphalangeal joint and a metacarpophalangeal joint that pivots around two axes and about an axis extending along a direction intersecting the parallel around the axis and this axis the rotation axis of the thumb mechanism is rotated in one axis A thumb interphalangeal joint that rotates and a single axis that rotates about an axis parallel to the rotation axis of the thumb interphalangeal joint A metacarpophalangeal joint, a first rotation axis having an axis parallel to the rotation axis of the thumb metacarpophalangeal joint, and an axis extending along a direction intersecting the axis of the first rotation axis a carpometacarpal joint pivots two axes of the second rotating shaft, a second rotation shaft of the carpometacarpal joint of the thumb mechanism is its axis, metacarpophalangeal of the index finger mechanism The finger mechanism is disposed so as to extend through the center between the joint and the middle finger joint of the middle finger mechanism in the fingertip direction of the indicating finger mechanism and the middle finger mechanism in an extended state . The drive cylinder is configured to be a second rotation shaft of the thumb mechanism, and includes a cylinder main body that is rotatably supported by the base portion. .

The thumb mechanism provided in the multi-finger hand device according to the present invention includes a 1-axis thumb interphalangeal joint, a 1-axis thumb metacarpophalangeal joint, and a 2-axis carpal joint. The same bending and stretching operation as the thumb can be performed. In addition, according to the present invention, the second rotation axis of the carpal middle joint of the thumb mechanism (that is, the rotation axis that performs the opening operation of the thumb mechanism) is configured so that the middle finger joint of the finger mechanism and the middle finger mechanism have the above structure. An axis extending between the metacarpophalangeal joints. According to this, when the fingertip of the thumb mechanism is opposed to the center between the fingertip of the index finger mechanism and the fingertip of the middle finger mechanism when performing an operation of picking up the object, the second rotation axis of the carpal joint , And the object can be stably gripped while suppressing unnecessary moments around the second rotation axis.
Further, the second rotation shaft, its axis, wherein the index finger mechanism of metacarpophalangeal joints through the center between the metacarpophalangeal joints of the middle finger mechanism, said extending condition index finger mechanism and the middle finger mechanism The fingertip of the thumb mechanism can be placed in a well-balanced manner against both the fingertip of the index finger mechanism and the fingertip of the middle finger mechanism, thereby obtaining an extremely stable object gripping state. be able to.
Further, the thumb mechanism includes a drive cylinder that drives a first rotation shaft of the carpal joint, and the drive cylinder serves as the second rotation shaft of the thumb mechanism and is rotatable. By providing the cylinder main body supported by the base, the thumb mechanism can be configured more compactly while obtaining a smooth operation of the carpal joint.

The present invention also includes a base and at least three finger mechanisms connected to the base, the three finger mechanisms each having a bending / extending function imitating the movement of the index finger in a human hand, A multi-finger hand device which is a middle finger mechanism having a bending / extension function imitating movement and a thumb mechanism having a bending / extension function imitating movement of a thumb, wherein the indicating finger mechanism and the middle finger mechanism are respectively A distal interphalangeal joint that rotates in one axis, a proximal interphalangeal joint that rotates in one axis about an axis parallel to the rotational axis of the distal interphalangeal joint, and the proximal phalange and a metacarpophalangeal joint that pivots around two axes and about an axis extending along a direction crossing between the axes of rotation and this parallel to the pivot axis of the joint, the thumb mechanism is a one-axis Rotating thumb interphalangeal joint and pivoting around one axis parallel to the pivot axis of the thumb interphalangeal joint A thumb metacarpophalangeal joint, a first rotation axis having an axis parallel to the rotation axis of the thumb metacarpophalangeal joint, and an axis extending along the direction intersecting the axis of the first rotation axis A carpal joint that rotates around two of the second rotation axes, and the second rotation axis of the carpal joint of the thumb mechanism has an axis line in the finger mechanism. The finger joint is disposed so as to extend through the center between the finger joint and the middle finger joint of the middle finger mechanism in the direction of the fingertip of the extended finger mechanism and the middle finger mechanism . The rotation shaft of 2 is formed hollow and is disposed in the base, and a drive cylinder for driving the rotation of the first rotation shaft is provided inside the second rotation shaft. It is characterized by.
The thumb mechanism provided in the multi-finger hand device according to the present invention includes a 1-axis thumb interphalangeal joint, a 1-axis thumb metacarpal joint, and a 2-axis carpal joint. The same bending and stretching operations can be performed. In addition, according to the present invention, the second rotation axis of the carpal middle joint of the thumb mechanism (that is, the rotation axis that performs the opening operation of the thumb mechanism) is configured so that the middle finger joint of the finger mechanism and the middle finger mechanism have the above structure. An axis extending between the metacarpophalangeal joints. According to this, when the fingertip of the thumb mechanism is opposed to the center between the fingertip of the index finger mechanism and the fingertip of the middle finger mechanism when performing an operation of picking up the object, the second rotation axis of the carpal joint , And the object can be stably gripped while suppressing unnecessary moments around the second rotation axis.
Further, the second rotation shaft, its axis, wherein the index finger mechanism of metacarpophalangeal joints through the center between the metacarpophalangeal joints of the middle finger mechanism, said extending condition index finger mechanism and the middle finger mechanism The fingertip of the thumb mechanism can be placed in a well-balanced manner against both the fingertip of the index finger mechanism and the fingertip of the middle finger mechanism, thereby obtaining an extremely stable object gripping state. be able to.
Furthermore, the drive cylinder that rotates the first rotation shaft of the carpal joint is stored inside the second rotation shaft, and the thumb mechanism is compact while obtaining smooth operation of the carpal joint. Can be configured.

1 is a schematic configuration diagram illustrating a multi-finger hand device according to an embodiment of the present invention. Explanatory drawing which shows typically each joint of a hand main body. Explanatory drawing which shows the internal structure of a hand main body from the back side of a hand. Explanatory sectional drawing which shows one of the finger mechanisms with which a hand main body is equipped. Explanatory sectional drawing which shows the thumb mechanism with which a hand main body is equipped. Explanatory drawing which shows typically the structure of a part of drive means in this embodiment. Explanatory drawing which shows typically the action | operation of a drive means.

  An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the multi-fingered hand device 1 of the present embodiment is composed of a hand main body 2 imitating a human hand and driving means 3 for driving the hand main body 2 and is preferably used for a so-called humanoid robot. It is something that can be done.

  The hand body 2 includes a base part 4, a thumb mechanism 5, an indicating finger mechanism 6, a middle finger mechanism 7, a ring finger mechanism 8, and a little finger mechanism 9, which are five finger mechanisms each having a bending and stretching function corresponding to five fingers. It has. The base 4 includes a frame 10 that connects and supports each finger mechanism, and the front side of the base 4 is the back of the hand and the back side is the palm. FIG. 1 shows the palm side of the hand body 2.

  Each finger mechanism is covered with a finger skin member 11 with each joint exposed, and the base portion 4 is covered with a base skin member 12.

  Each finger mechanism includes a plurality of finger joints and joints as schematically shown in FIG. The index finger mechanism 6, the middle finger mechanism 7, the ring finger mechanism 8, and the little finger mechanism 9 are respectively a DIP joint 13 (distal interphalangeal joint), a PIP joint 14 (proximal interphalangeal joint), respectively, from the fingertip side. An MP1 joint 15 and an MP2 joint 16 are provided, and each joint is rotatable.

The DIP joint 13 rotates about one axis, and the PIP joint 14 rotates about one axis parallel to the DIP joint 13. MP1 joint 15 and MP2 joint 16, which forms the metacarpophalangeal joints rotated biaxially, MP1 joint 15, rotates about an axis parallel with the PIP joint 14, MP2 joint 16, It rotates about an axis extending along the direction intersecting the axis of the MP1 joint 15.

  The DIP joint 13, the PIP joint 14, and the MP1 joint 15 are configured to rotate in a direction toward the palm side of the base 4 to perform bending and stretching movements such as a gripping operation. The MP2 joint 16 can swing each finger mechanism in a direction in which each finger mechanism approaches or separates, for example, an operation of spreading a hand.

  As shown schematically in FIG. 2, the thumb mechanism 5 includes, in order from the fingertip side, an IP joint 17 (finger interphalangeal joint), an MP joint 18 (finger metacarpophalangeal joint), a CM1 joint 19 and a CM2 joint 20. It is possible to rotate for each joint.

The IP joint 17 rotates about one axis, and the MP joint 18 rotates about one axis parallel to the IP joint 17. CM1 joint 19 and CM2 joint 20, which forms the carpometacarpal joint pivots biaxial, CM1 joint 19, rotates about an axis parallel with the MP joint 18, CM2 joint 20 Rotate about an axis extending along the direction intersecting the axis of the CM1 joint 19.

  The IP joint 17, the MP joint 18, and the CM 1 joint 19 rotate in the direction toward the palm side of the base 4 or the finger pad side of any of the other four finger mechanisms 6, 7, 8, 9. Bending and stretching movements such as gripping movements can be performed. The CM2 joint 20 rotates the thumb mechanism 5 so as to face the palm side or the finger pad side of any of the other four finger mechanisms 6, 7, 8, 9.

  Of the five finger mechanisms, the thumb finger mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 correspond to the three finger mechanisms of the present invention, and are dexterous fingers that perform dexterous operations including a pinch operation at the fingertips, as will be described later. The ring finger mechanism 8 and the little finger mechanism 9 are force fingers that perform a force operation including a gripping operation according to the operation of the dexterous finger.

  As shown in FIGS. 3 and 4, the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 that are dexterous fingers include a six-axis force sensor 21 that is a force sensor. The six-axis force sensor 21 is attached to each fingertip member 22 of the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 in an inclined posture. The six-axis force sensor 21 measures a six-axis force acting on the fingertip member 22 of a dexterous finger, that is, a translational force in three orthogonal directions (x-axis, y-axis, z-axis) and a moment around each axis. To do. The fingertip force of the dexterous finger is controlled based on the measurement value of the six-axis force output from the six-axis force sensor 21.

  Explaining the configuration of the finger mechanism 6, as shown in FIG. 4, the finger mechanism 6 includes a first driven fluid pressure cylinder 23 that rotates the rotation shaft 151 of the MP1 joint 15 and a rotation of the PIP joint 14. And a second driven fluid pressure cylinder 24 for rotating the shaft 141.

  The cylinder body 231 of the first driven fluid pressure cylinder 23 corresponds to a human metacarpal bone, and is supported by the frame 10 (see FIG. 1) of the base 4 so as to be rotatable by the rotation shaft 161 of the MP2 joint 16. ing. The cylinder body 241 of the second driven fluid pressure cylinder 24 corresponds to a human proximal phalanx, and is rotatably connected to the first driven fluid pressure cylinder 23 via the rotation shaft 151 of the MP1 joint 15. Yes.

  A pipe 244 that supplies fluid to the cylinder body 241 of the second driven fluid pressure cylinder 24 is accommodated in the rotation shaft 151 of the MP1 joint 15. Thereby, the piping 244 does not get in the way when the MP1 joint 15 is rotated, and the bending operation of the index finger mechanism 6 can be performed smoothly.

  In addition, by arranging the cylinder body 241 of the second driven fluid pressure cylinder 24 between the MP1 joint 15 and the PIP joint 14 along the longitudinal direction of the finger mechanism 6, the finger mechanism 6 can be configured in a compact manner. Can do.

  The DIP joint 13 is connected to the PIP joint 14 via a connecting member 25 corresponding to a human middle phalanx. A support member 26 that supports the six-axis force sensor 21 connected to the fingertip member 22 is rotatably connected to the rotation shaft 131 of the DIP joint 13. One end of the connecting member 25 is rotatably connected to the rotating shaft 141 of the PIP joint 14, and the other end is connected to the rotating shaft 131 of the DIP joint 13.

  Further, a link member 27 is provided between the PIP joint 14 and the DIP joint 13. The link member 27 connects the cylinder body 241 of the second driven fluid pressure cylinder 24 and the support member 26 that supports the six-axis force sensor 21 of the fingertip member 22.

  In the first driven fluid pressure cylinder 23, when the fluid is supplied into the cylinder body 231, the piston 232 slides and the piston rod 233 expands and contracts to rotate the MP1 joint 15. Thereby, the index finger mechanism 6 bends and stretches via the MP1 joint 15.

  In the second driven fluid pressure cylinder 24, when the fluid is supplied into the cylinder body 241, the piston 242 slides and the piston rod 243 expands and contracts to rotate the PIP joint 14. At this time, since the PIP joint 14 and the DIP joint 13 are connected by the connecting member 25 and the link member 27, the DIP joint 13 follows the rotation of the PIP joint 14 by the second driven fluid pressure cylinder 24. Rotate.

  Since the DIP joint 13 is configured to be interlocked with the rotation of the PIP joint 14 by the second driven fluid pressure cylinder 24, not only can the operation be similar to the movement of a human finger, A cylinder or the like for driving becomes unnecessary, and the index finger mechanism 6 can be configured to be lightweight.

  With the above configuration, the finger mechanism 6 is bent by extending the piston rods 231 and 241 of the first driven fluid pressure cylinder 23 and the second driven fluid pressure cylinder 24 and contracts the piston rods 231 and 241. It will be in an extended state.

  As shown in FIG. 3, the MP2 joint 16 of the index finger mechanism 6 is rotated by a third driven fluid pressure cylinder 28 in which the piston rod 283 expands and contracts along the arrangement direction of the finger mechanisms. The third driven fluid pressure cylinder 28 swings the index finger mechanism 6 in a direction close to the middle finger mechanism 7 by extending the piston rod 283 and contracts the piston rod 283 from the middle finger mechanism 7 by contracting the piston rod 283. Swing in the direction of separation.

  As shown in FIG. 4, coil springs 14 s, 15 s, and 16 s (torsion springs) are provided in each of the PIP joint 14, the MP1 joint 15, and the MP2 joint 16. The coil springs 14s, 15s of the PIP joint 14 and the MP1 joint 15 extend the finger mechanism 6 in the extending direction. The coil spring 16 s of the MP2 joint 16 urges the index finger mechanism 6 in a direction in which it is separated from the middle finger mechanism 7. In other words, the urging directions of the coil springs 14s, 15s, and 16s are the same as the contraction directions of the piston rods 233, 243, and 283 of the three driven fluid pressure cylinders 23, 24, and 28.

  Although the configuration of the index finger mechanism 6 has been described in detail above, the configuration of the middle finger mechanism 7 is also the same as that of the index finger mechanism 6, and thus description thereof is omitted.

  The ring finger mechanism 8 and the little finger mechanism 9, which are the force fingers, of the above-described configuration of the finger mechanism 6, except that the six-axis force sensor 21 and the third driven fluid pressure cylinder 28 are not provided. It is the same composition as. Since the ring finger mechanism 8 and the little finger mechanism 9 do not include the third driven fluid pressure cylinder 28, the MP2 joint 16 freely rotates according to the force operation, and the MP2 joint 16 is biased by the coil spring 16 s. It naturally returns to a predetermined position.

  Next, the structure of the thumb mechanism 5 used as a dexterous finger will be described. As shown in FIG. 5, the thumb mechanism 5 includes a first driven fluid pressure cylinder 29 (drive cylinder) that rotates the rotation shaft 191 of the CM1 joint 19 (the first rotation shaft of the carpal-carpal joint). And a second driven fluid pressure cylinder 30 for rotating the rotation shaft 181 of the MP joint 18.

  The cylinder body 291 of the first driven fluid pressure cylinder 29 is used as a rotation axis of the CM2 joint 20 (second rotation axis of the carpal joint), and the frame 10 of the base 4 is freely rotatable. It is supported by.

  As shown in FIGS. 2 and 3, the axis a of the rotation axis of the CM2 joint 20 (the cylinder body 291 of the first driven fluid pressure cylinder 29) is the middle finger joint and the middle finger mechanism 7. The middle finger phalangeal joint is disposed so as to extend in the fingertip direction of the extended finger mechanism 6 and the middle finger mechanism 7 preferably through the center. According to this, when performing the object pinching operation, the fingertip of the thumb mechanism 5 can be opposed to the center of the fingertip of the index finger mechanism 6 and the fingertip of the middle finger mechanism 7 to reduce the rotation operation around the CM2 joint 20. Out. In addition, the fingertip of the thumb mechanism 5 can be opposed to both the fingertip of the index finger mechanism 6 and the fingertip of the middle finger mechanism 7 with good balance. As a result, an unnecessary moment around the CM2 joint 20 can be suppressed and the object can be stably grasped, and the accuracy of the measurement value by each 6-axis force sensor 21 can be improved, and the fingertip force on the dexterous finger can be controlled. It can be performed with high accuracy.

  Furthermore, when the cylinder body 291 of the first driven fluid pressure cylinder 29 is also used as the CM2 joint 20 rotation shaft, the first driven fluid pressure cylinder 29 and the rotation shaft of the CM2 joint 20 are provided separately. It becomes compact compared to. In addition, the first driven fluid pressure cylinder 29 does not oscillate as the CM2 joint 20 rotates, and the oscillating space is not required. Therefore, the configuration can be made extremely compact.

  The cylinder body 301 of the second driven fluid pressure cylinder 30 is rotatably connected to the first driven fluid pressure cylinder 29 via the rotation shaft 191 of the CM1 joint 19.

  A pipe 304 that supplies fluid to the cylinder body 301 of the second driven fluid pressure cylinder 30 is housed inside the rotation shaft 191 of the CM1 joint 19. Thereby, the piping 304 does not get in the way when the CM1 joint 19 is rotated, and the bending mechanism of the thumb mechanism 5 can be smoothly performed.

  An IP joint 17 is connected to the MP joint 18 via a connecting member 31. A fingertip member 22 is rotatably connected to the rotation shaft 171 of the IP joint 17. One end of the connecting member 31 is rotatably connected to the rotating shaft 181 of the MP joint 18, and the other end is connected to the rotating shaft 171 of the IP joint 17.

  Further, a link member 32 is provided between the MP joint 18 and the IP joint 17. The link member 32 connects the cylinder body 301 of the second driven fluid pressure cylinder 30 and the support member 33 that supports the six-axis force sensor 21 of the fingertip member 22.

  In the first driven fluid pressure cylinder 29, when the fluid is supplied into the cylinder body 291, the piston 292 slides and the piston rod 293 expands and contracts to rotate the CM1 joint 19. Thereby, the index finger mechanism 6 bends and stretches via the CM1 joint 19.

  In the second driven fluid pressure cylinder 30, when a fluid is supplied into the cylinder body 301, the piston 302 slides and the piston rod 303 expands and contracts to rotate the MP joint 18. At this time, since the MP joint 18 and the IP joint 17 are connected by the connecting member 31 and the link member 32, the IP joint follows the rotation of the MP joint 18 by the second driven fluid pressure cylinder 30. 17 rotates.

  Since the IP joint 17 is configured to be interlocked with the rotation of the MP joint 18 by the second driven fluid pressure cylinder 30, not only an operation close to the movement of a human finger can be obtained, but also the IP joint 17 A cylinder or the like for driving becomes unnecessary, and the thumb mechanism 5 can be configured to be lightweight.

  With the above configuration, the thumb mechanism 5 is bent by extending the piston rods 293 and 303 of the first driven fluid pressure cylinder 29 and the second driven fluid pressure cylinder 30 and contracts the piston rods 293 and 303. It will be in an extended state.

  As shown in FIG. 3, the CM2 joint 20 of the thumb mechanism 5 is rotated around the axis a by a third driven fluid pressure cylinder 34 in which the piston rod 343 extends and contracts along the arrangement direction of the finger mechanisms.

  The thumb mechanism 5 extends to the palm side of the base 4 by extending the piston rod 343 of the third driven fluid pressure cylinder 34 and contracts the piston rod 343 of the third driven fluid pressure cylinder 34. It rotates in a direction adjacent to the index finger mechanism 6.

  As shown in FIG. 5, the supply of fluid to the cylinder body 291 of the first driven fluid pressure cylinder 29 is performed by the bearing portion of the cylinder body 291 of the first driven fluid pressure cylinder 29 that is the rotation shaft of the CM2 joint 20. This is performed via a fluid path 294 formed in the interior of 101. Thereby, the cylinder main body 291 of the first driven fluid pressure cylinder 29 can be smoothly rotated, and the thumb mechanism 5 can be smoothly rotated by the CM2 joint 20.

  As shown in FIGS. 3 and 5, coil springs 18s, 19s, and 20s (torsion springs) are provided in the MP joint 18, the CM1 joint 19, and the CM2 joint 20, respectively. The coil springs 18s and 19s of the MP joint 18 and the CM1 joint 19 extend the thumb mechanism 5 in the extending direction. The coil spring 20s of the CM2 joint 20 is provided so as to surround the outer periphery of the cylinder body 291 of the first driven fluid pressure cylinder 29, and is attached in a direction in which the thumb mechanism 5 is rotated in a direction adjacent to the index finger mechanism 6. Rush. In other words, the biasing directions of the coil springs 18s, 19s, and 20s are the same as the contraction directions of the piston rods 293, 303, and 343 of the three driven fluid pressure cylinders 29, 30, and 34.

  Although not shown, the finger skin member 11 covering the finger pad side of the hand body 2 and the base skin member 12 covering the palm side are provided with a plurality of contact sensors at predetermined positions.

  The configuration of the hand body 2 has been described above. Next, the driving means 3 for driving each finger mechanism of the hand body 2 will be described.

  As shown in FIG. 1, the driving means 3 includes a driving cylinder unit 35 provided outside the hand body 2, a controller 36 that controls the hand body 2 via the driving cylinder unit 35, and each of the driven fluids described above. The pressure cylinders 23, 24, 28, 29, 30, and 34 are configured.

  As shown in FIG. 1, the drive cylinder unit 35 includes a plurality of drive fluid pressure cylinders 37. As shown in FIG. 6, the driving fluid pressure cylinder 37 includes a cylinder main body 371 that contains fluid, a piston 372 that slides inside the cylinder main body 371, and a hollow piston rod 373 that is connected to the piston 372. And. Further, the drive fluid pressure cylinder 37 includes a ball screw 38 inserted into the piston rod 373 along the axis of the piston rod 373, and a nut 39 fixed inside the piston rod 373 and screwed into the ball screw 38. The motor 40 is configured to move the piston rod 373 back and forth through the nut 39 by rotationally driving the ball screw 38, and the encoder 41 for detecting the operation amount of the motor 40.

  The motor 40 rotationally drives the ball screw 38 via a belt 44 hung on pulleys 42 and 43 as rotation transmission means. Thereby, the axis line of the output shaft 401 of the motor 40 and the piston rod 373 becomes parallel, and the motor 40 can be provided adjacent to the cylinder main body 371 to be compact.

  A total of 13 drive fluid pressure cylinders 37 of the drive cylinder unit 35 are provided corresponding to the driven fluid pressure cylinders 23, 24, 28, 29, 30, 34 incorporated in the hand body 2, one by one. It has been. Although schematically shown in FIG. 1, each of the driving fluid pressure cylinders 37 of the driving cylinder unit 35 and each of the driven fluid pressure cylinders 23, 24, 28, 29, 30, 34 of the hand body 2 are each a fluid pressure transmission pipe. 45 and connected separately.

  With this configuration, as shown schematically in FIGS. 7A and 7B, if the fluid is sent and sucked into the driving fluid pressure cylinder 37, each driven fluid pressure cylinder 23 (24, 28, 29, 30, 34), the fluid is press-fitted and discharged, and the finger mechanism 6 (7, 8, 9, 5) is driven by the driven fluid pressure cylinder 37. At this time, the controller 36 controls the fluid delivery amount and the suction amount in the driving fluid pressure cylinder 37 via the motor 40, whereby the finger mechanism 6 is driven by the driven fluid pressure cylinder 23 (24, 28, 29, 30, 34). (7, 8, 9, 5) can be made to perform desired bending and stretching operations. By providing the drive cylinder unit 35 outside the hand main body 2, the hand main body 2 can be made small and light, and for example, the hand main body 2 having the same size as a standard human hand can be obtained. Further, since each finger mechanism 5, 6, 7, 8, 9 is operated by the fluid pressure of each driving fluid pressure cylinder 37 and each driven fluid pressure cylinder 23, 24, 28, 29, 30, 34, it is small in size. Sufficient gripping force can be obtained.

  Further, as shown in FIG. 1, the controller 36 is connected to the drive cylinder unit 35 via the signal line 46, and the driven fluid pressure cylinders 37 to the driven fluid pressure cylinders 23, 24, 28, 29, 30, 34. The bending and stretching of each finger mechanism is controlled by adjusting the working fluid pressure transmitted to. Further, the controller 36 is connected to the hand main body 2 via the signal line 47 and obtained from each of the six-axis force sensors 21 of the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 that are used as dexterous fingers and the contact sensor. Based on the obtained information, each drive fluid pressure cylinder 37 is controlled. Accordingly, the controller 36 performs control so that a gripping operation imitating a human operation is performed by each finger mechanism of the hand body 2 having the above-described configuration.

  For example, when the controller 36 performs an operation of grasping a cylindrical object (not shown) by each finger mechanism of the hand body 2, the controller 36 controls the finger mechanism as follows.

  First, an operation of pinching an object with the fingertips of the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 which are dexterous fingers is performed. At this time, the axis a (see FIG. 2) of the rotation axis (cylinder body 291) of the CM2 joint 20 extends through the center between the middle finger joint of the index finger mechanism 6 and the middle finger joint of the middle finger mechanism 7. Since the fingertip of the thumb mechanism 5 smoothly faces between the fingertip of the index finger mechanism 6 and the fingertip of the middle finger mechanism 7, the pinching state of the object is extremely stable.

  Next, the object is gripped by the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 until it comes into contact with the base skin member 12 on the palm side. At this time, the controller 36 determines the position, size, and position of the object based on the information of each 6-axis force sensor 21 and the contact sensors provided on the finger skin member 11 on the finger pad side and the base skin member 12 on the palm side. Calculate posture, etc. Since the controller 36 operates the thumb mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 based on the calculation result, the posture of the object while balancing the object when continuously shifting from the pinching operation to the gripping operation. Can be manipulated dexterously. Moreover, since the axis a of the rotation axis (cylinder main body 291) of the CM2 joint 20 is at the center between the middle finger joint of the index finger mechanism 6 and the middle finger joint of the middle finger mechanism 7, unnecessary mo- mains are not generated. The posture of the object can be stabilized even when shifting to the gripping operation.

  Subsequently, the controller 36 operates the ring finger mechanism 8 and the little finger mechanism 9 to grasp the object with a relatively strong force by the ring finger mechanism 8 and the little finger mechanism 9 which are the finger fingers. The mechanism 6 and the middle finger mechanism 7 hold the object with a relatively strong force. By performing such an operation under the control of the controller 36, it is possible to perform an object gripping operation imitating a human being.

  In the above-described embodiment, the multi-finger hand device 1 including five finger mechanisms simulating a human hand has been described. However, for example, the thumb finger mechanism 5, the index finger mechanism 6, and the middle finger mechanism 7 may be used.

  DESCRIPTION OF SYMBOLS 1 ... Multi-finger hand apparatus, 4 ... Base, 5 ... Thumb mechanism, 6 ... Indicating finger mechanism, 7 ... Middle finger mechanism, 13 ... DIP joint (distal interphalangeal joint), 14 ... PIP joint (proximal interphalangeal joint) ), 15... MP1 joint (metacarpal joint), 16... MP2 joint (metacarpal joint), 17... IP joint (interphalangeal joint), 18. CM1 joint (carpal joint), 20 ... CM2 joint (carpal joint), 29 ... first driven fluid pressure cylinder (drive cylinder), 191 ... rotation axis (first rotation axis), 291 ... Cylinder body (second rotating shaft).

Claims (2)

A base, and at least three finger mechanisms connected to the base, the three finger mechanisms each having a flexion / extension function imitating the movement of the index finger in a human hand, and a flexion / extension function imitating the movement of the middle finger A multi-finger hand device which is a middle finger mechanism having a thumb and a thumb mechanism having a bending and stretching function imitating the movement of a thumb,
Each of the index finger mechanism and the middle finger mechanism is rotated about one axis about a distal interphalangeal joint that rotates about one axis, and an axis parallel to the rotation axis of the distal interphalangeal joint. metacarpophalangeal that pivots about two axes of the proximal interphalangeal joint, the axis around which extends along a direction intersecting the axis around the axis and this parallel to the rotation axis of the joint between the proximal phalanx of With articulated joints,
The thumb mechanism includes a thumb interphalangeal joint that rotates about one axis, a thumb metacarpophalangeal joint that rotates about one axis around an axis parallel to the rotation axis of the thumb interphalangeal joint, and the middle finger Two axes of a first rotation axis having an axis parallel to the rotation axis of the finger joint and a second rotation axis having an axis extending along the direction intersecting the axis of the first rotation axis With a carpal joint that rotates,
It said second pivot axis of the carpometacarpal joint of the thumb mechanism is its axis, through the center between the metacarpophalangeal joints of the metacarpophalangeal joint of the index finger mechanism the middle finger mechanism, extended state Arranged to extend in the fingertip direction of the index finger mechanism and the middle finger mechanism ,
The thumb mechanism includes a drive cylinder that drives the first rotation shaft, and the drive cylinder serves as the second rotation shaft of the thumb mechanism and is rotatably supported by the base portion. A multi-finger hand device comprising a main body. A base, and at least three finger mechanisms connected to the base, the three finger mechanisms each having a flexion / extension function imitating the movement of the index finger in a human hand, and a flexion / extension function imitating the movement of the middle finger A multi-finger hand device which is a middle finger mechanism having a thumb and a thumb mechanism having a bending and stretching function imitating the movement of a thumb,
Each of the index finger mechanism and the middle finger mechanism is rotated about one axis about a distal interphalangeal joint that rotates about one axis, and an axis parallel to the rotation axis of the distal interphalangeal joint. metacarpophalangeal that pivots about two axes of the proximal interphalangeal joint, the axis around which extends along a direction intersecting the axis around the axis and this parallel to the rotation axis of the joint between the proximal phalanx of With articulated joints,
The thumb mechanism includes a thumb interphalangeal joint that rotates about one axis, a thumb metacarpophalangeal joint that rotates about one axis around an axis parallel to the rotation axis of the thumb interphalangeal joint, and the middle finger Two axes of a first rotation axis having an axis parallel to the rotation axis of the finger joint and a second rotation axis having an axis extending along the direction intersecting the axis of the first rotation axis With a carpal joint that rotates,
It said second pivot axis of the carpometacarpal joint of the thumb mechanism is its axis, through the center between the metacarpophalangeal joint of the metacarpophalangeal joint of the index finger mechanism the middle finger mechanism, extended state Arranged to extend in the fingertip direction of the index finger mechanism and the middle finger mechanism ,
The second rotation shaft of the thumb mechanism is formed hollow and disposed at the base, and a drive cylinder that drives the rotation of the first rotation shaft inside the second rotation shaft A multi-fingered hand device characterized by that.