JP5289179B2 - Robot hand and its control system, control method and control program - Google Patents

Description

  The present invention relates to a robot hand that includes a palm and a plurality of fingers extending from the palm, and performs adjustment of the position and posture of the palm and gripping of an object by each movement of the plurality of fingers.

  There has been proposed a method of controlling the operation of a robot hand so as to hold or change the way of holding the object after grasping the object (see Patent Document 1).

JP 2005-349491 A

  However, if an object placed at a location is pinched by multiple finger mechanisms and lifted from this location without being firmly grasped, the force of the finger mechanisms is insufficient due to the multiple finger mechanisms This may cause the object to fall. In particular, when the balance of an object when it is picked up by a plurality of finger mechanisms is deflected, the posture of the object changes, and there is a possibility that it may cause trouble when gripping the object thereafter. Although it is conceivable to increase the force of the finger mechanism in order to securely pick up the object, it is not preferable because the driving mechanism for driving the finger mechanism is increased in weight and size.

  Accordingly, an object of the present invention is to provide a system or the like that can control the operation of the hand so that the object can be stably lifted from the placement location.

A control system of the present invention for solving the above problems is a control system for a robot hand comprising a palm and a plurality of finger mechanisms extending from the palm, wherein the position of the palm And the position of the palm and the movement of the plurality of finger mechanisms are controlled based on the first calculation processing element for recognizing the position and posture of the object and the recognition result of the first calculation processing element. A second arithmetic processing element, and the second arithmetic processing element is placed at a certain position by controlling movement of two or more first type finger mechanisms among the plurality of finger mechanisms. By holding an object on the first type finger mechanism and controlling part or all of the position and posture of the palm and the movement of the first type finger mechanism, the object becomes the first type finger mechanism. While being pinched by a mechanism, a part of the object is in contact with the location, while the other body is changed in posture so that it floats from the location, and a part of the palm of the hand is placed on the object. And the movement of the second type of finger mechanism that is separated from the first type of finger mechanism among the plurality of finger mechanisms is controlled by the second type of finger mechanism. was gripped part that floats from the point, the position of the palm portion, by controlling the orientation or position and orientation, and the second type of the palm portion in a state where the finger mechanism the object is gripped with the object In addition to the second type finger mechanism, the first type finger mechanism is caused to grip the object by increasing the area of the contact portion of the first type and controlling the movement of the first type finger mechanism. It is characterized by that.

  According to the control system of the present invention, the object is pinched by the movement of the first type finger mechanism, and the other part is lifted while keeping a part of the object in contact with the placement position. At this time, since the total mass of the object is not applied to the first type finger mechanism, it is not necessary to increase the force of the first type finger mechanism to the extent that the object is picked up. Therefore, the weight reduction or size reduction of the drive mechanism of the first type finger mechanism can be achieved.

  Next, by controlling the position, posture or position and posture of the palm, the contact portion between the palm and the object is expanded, and the movement of the plurality of finger mechanisms is controlled. An object is gripped by a plurality of finger mechanisms. For this reason, the object is firmly held in a state where the object is in contact with the palm and each of the plurality of finger mechanisms. Then, the object can be stably lifted from the placement location while being firmly held by the hand.

  Note that the component of the present invention “recognizes” information means that the component as a computer hardware resource (CPU or the like) reads information from a storage device, retrieves information from a database, Information, measuring, calculating, estimating or predicting information by appropriately performing arithmetic processing based on basic information output from a sensor, and storing information in a storage device, etc. It means any information calculation processing that prepares information in a usable state for necessary calculation processing or the like.

  In the control system of the first invention, the first arithmetic processing element recognizes a division between a heavy part having a high mass density across the center of mass position of the object and a lightweight part having a lower mass density than the heavy part. The second arithmetic processing element controls the movement of the first type finger mechanism, so that the lightweight part of the object placed at the location is held on the first type finger mechanism, By controlling part or all of the position and posture of the palm and the movement of the first type finger mechanism, the lightweight portion of the object is pinched by the first type finger mechanism, While the object is in contact with the portion in the weight portion, the posture of the object may be changed so that the lightweight portion is lifted from the portion, and the palm portion may be partially in contact with the object ( 2 invention).

  According to the control system configured as described above, a place that can be held by the first type finger mechanism is selected in view of the deflectability of the mass distribution of the object, so that the load on the first type finger mechanism is reduced. For this reason, the posture of the object changed while being pinched by the first type finger mechanism can be stably maintained. Therefore, following this, the object can be lifted stably from its place by firmly grasping the object by the hand as described above.

  In the control system according to the first or second invention, the second arithmetic processing element controls the movement of the second kind of finger mechanism, so that the second kind of finger mechanism floats from the part of the object. The first type finger mechanism is moved away from the object while the object is held by the second type finger mechanism by controlling the movement of the first type finger mechanism. After the separation, the area of the contact portion between the palm and the object may be increased by controlling the position, posture or position and posture of the palm (third invention).

  According to the control system having the above configuration, the first type finger mechanism and the object are not bound to each other's movement or the like by separating the first type finger mechanism from the object. The position, posture or position and posture of the part can be easily changed. Thereby, from the viewpoint of causing the hand to hold the object firmly, the contact portion between the palm of the hand and the object can be appropriately and sufficiently widened. As a result, the object can be firmly grasped by the hand as described above, and the object can be stably lifted from the placement position.

  In the control system of the third invention, there are two or more of the second type finger mechanisms, and the second arithmetic processing element controls the movement of some of the second type of finger mechanisms, thereby After the portion of the object floating above the part is held by some second-type finger mechanisms, the movement of the first-type finger mechanism is controlled, whereby the some second-type fingers are controlled. The first type finger mechanism is separated from the object in a state where the object is held by the mechanism, and then the movement of the remaining second type finger mechanisms is controlled, whereby the part of the second type In addition to the finger mechanism, the remaining second-type finger mechanism may hold a portion of the object floating from the location (fourth invention).

  According to the control system of the configuration, the object is grabbed by only a part of the second type finger mechanism, and the remaining second type finger mechanism and the object are not bound to each other's movement, etc. Accordingly, the position, posture or position and posture of the palm can be easily changed. Thereby, from the viewpoint of causing the hand to hold the object firmly, the contact portion between the palm of the hand and the object can be appropriately and sufficiently widened. As a result, the object can be firmly grasped by the hand as described above, and the object can be stably lifted from the placement position.

  In one control system of the first to fourth inventions, there is a difference in the degree of freedom of active movement in the plurality of finger mechanisms, and a finger mechanism having a high degree of freedom is defined as the first type finger mechanism. While controlling the movement, the finger mechanism having a low degree of freedom may be controlled as the second type finger mechanism (the fifth invention).

  According to the control system of this configuration, the first type of finger mechanism having a relatively high degree of freedom of active movement is suitable for an operation of “pinch” that requires dexterity rather than an operation of “grabbing” an object. In view of the above, each operation of the plurality of finger mechanisms can be appropriately controlled according to the function or role thereof.

  In this configuration, the structure or mechanism related to some finger mechanisms has been simplified in order to reduce the weight or the size of the hand, so that the degree of freedom of active movement of the some finger mechanisms is different. This is particularly significant when designed to be low compared to the finger mechanism.

  In one control system of the first to fifth inventions, a part of an edge of the palm is formed in a rounded shape that is continuous with a plane of the hand, and the second arithmetic processing element is a position of the palm. By controlling part or all of the movement of the first kind of finger mechanism and the posture, a part formed in the rounded shape of the edge of the palm is first brought into contact with the object. Then, by controlling the position, posture or position and posture of the palm part, the plane of the hand of the palm part and the object are brought into contact with the object while the object is held by the second type finger mechanism. You may increase the area of a contact location (6th invention).

  According to the control system having the above configuration, when the palm of the hand first comes into contact with the object in the rounded part, the contact part between the hand plane and the object that is continuous with the rounded part is smoothly smoothed. Can be increased. Thereby, from the viewpoint of causing the hand to hold the object firmly, the contact portion between the palm of the hand and the object can be appropriately and sufficiently widened. Then, as described above, the object can be firmly held by the hand, and the object can be stably lifted from the placement location.

  A robot hand according to the present invention includes a palm portion, a plurality of finger mechanisms extending from the palm portion, and a control system according to any one of the first to sixth inventions. .

  The robot hand control program of the present invention causes a computer to function as any one of the control systems of the first to sixth inventions.

The control method of the present invention is a control method of a robot hand comprising a palm part and a plurality of finger mechanisms extending from the palm part, the position and posture of the palm part, and the object Recognizing the position and orientation, and controlling the movement of two or more first-type finger mechanisms of the plurality of finger mechanisms based on the recognition result, the object placed at a certain location is The object can be held by the first type of finger mechanism by being held by the first type of finger mechanism and controlling part or all of the position and posture of the palm and the movement of the first type of finger mechanism. While being pinched, a part of the object is in contact with the part, while the posture of the object is changed so that another part is lifted from the part, and a part of the palm is applied to the object. The plurality of By controlling the movement of the two finger mechanisms which are classified as the first type of finger mechanisms among the mechanism, so gripped part that floats from the point of the object to the second type of finger mechanisms By controlling the position, posture or position and posture of the palm, the area of the contact portion between the palm and the object can be increased while the object is held by the second type finger mechanism. In addition to controlling the movement of the first type finger mechanism, the first type finger mechanism is caused to grip the object in addition to the second type finger mechanism.

The structure explanatory view of the robot which has a hand as one embodiment of the present invention. FIG. FIG. The structure explanatory view of the 1st finger mechanism which a hand has. Structure explanatory drawing of the 2nd finger mechanism which a hand has. Structure explanatory drawing of a hand and a drive device. Explanatory drawing regarding the action | operation of a hand. FIG. 3 is a configuration explanatory diagram of a hand control system. Explanatory drawing regarding the control method of operation | movement of a hand. Explanatory drawing regarding the control method of the holding | grip operation | movement of the object by operation | movement of a hand. Explanatory drawing regarding the control method of the holding | grip operation | movement of the object by operation | movement of a hand.

  An embodiment of the present invention will be described with reference to the drawings.

  First, a configuration of a robot having a robot hand as a component as an embodiment of the present invention will be described.

  The robot R shown in FIG. 1 is a legged mobile robot. Like a human, the robot R extends from both sides of the base B0, the head B1 disposed above the base B0, and the top of the base B0. The left and right arm bodies B2, the hand 1 provided at the tip of each of the left and right arm bodies B2, and the left and right leg bodies B4 extending downward from the lower portion of the base body B0 are provided. The robot R may be not only a legged mobile robot but also any kind of robot having a mechanism corresponding to the arm body B2 for changing the position and posture of the hand 1.

  The robot R includes a control device 2 that controls its operation. The control device 2 may be a distributed control device including a main control unit and one or a plurality of sub control units connected through an internal network of the robot R.

  The base B0 is composed of an upper part and a lower part that are connected vertically so as to be relatively rotatable about the yaw axis. The head B1 can move, such as rotating around the yaw axis with respect to the base B0. The head B1 is mounted with a pair of left and right head cameras C1 that can sense light in various frequency bands, such as a CCD camera and an infrared camera that have an imaging range in front of the robot R. A waist camera (active sensor) for measuring the position, orientation, and the like of the object by detecting the reflected light of the object of the near-infrared laser light emitted toward the front lower side of the robot R below the base B0. ) C2 is installed.

  The arm body B2 includes a first arm body link B22 and a second arm body link B24. The base body B0 and the first arm body link B21 are connected via a shoulder joint mechanism (first arm joint mechanism) B21, and the first arm body link B22 and the second arm body link B24 are connected to an elbow joint mechanism (second arm). The second arm link B24 and the hand 1 are connected via a wrist joint mechanism (third arm joint mechanism) B25. The shoulder joint mechanism B21 has a degree of freedom of rotation around the roll, pitch and yaw axes, the elbow joint mechanism B23 has a degree of freedom of rotation around the pitch axis, and the wrist joint mechanism B25 is around the roll, pitch and yaw axes. It has a degree of freedom of rotation.

  The leg B4 includes a first leg link B42, a second leg link B44, and a foot B5. The base B0 and the first leg link B42 are connected via a hip joint mechanism (first leg joint mechanism) B41, and the first leg link B42 and the second leg link B44 are connected to a knee joint mechanism (second leg joint). The mechanism) is connected via B43, and the second leg link B44 and the foot B5 are connected via an ankle joint mechanism (third leg joint mechanism) B45.

  The hip joint mechanism B41 has a degree of freedom of rotation about the roll, the pitch, and the roll axis, the knee joint mechanism B43 has a degree of freedom of rotation about the pitch axis, and the ankle joint mechanism B45 rotates about the roll and the pitch axis. Has a degree of freedom. The hip joint mechanism B41, the knee joint mechanism B43, and the ankle joint mechanism B45 constitute a “leg joint mechanism group”. The translational and rotational degrees of freedom of each joint mechanism included in the leg joint mechanism group may be changed as appropriate. In addition, an arbitrary one of the hip joint mechanism B41, the knee joint mechanism B43, and the ankle joint mechanism B45 may be omitted, and the leg joint mechanism group may be configured by a combination of the remaining two joint mechanisms. . Further, when the leg body B4 has a second leg joint mechanism different from the knee joint, the leg joint mechanism group may be configured to include the second leg joint mechanism. An elastic material B52 as disclosed in Japanese Patent Application Laid-Open No. 2001-129774 is provided on the bottom of the foot B5 in order to alleviate the impact when landing.

[Explanation about the hand]
Here, the configuration of the hand 1 will be described.

  The hand 1 includes a palm portion 10 and five finger mechanisms 11 to 15 extending from the palm portion 10. The palm portion 10 includes a frame 101 that connects and supports each finger mechanism, and the front side of the palm portion 10 is the back of the hand and the back side is the palm. FIG. 3 shows the palm side of the hand 1. The palm 10 is covered with a palm skin member 102. Each of the first finger mechanism 11, the second finger mechanism 12, the third finger mechanism 13, the fourth finger mechanism 14, and the fifth finger mechanism 15 includes five fingers of a human hand, that is, a thumb, an index finger, a middle finger, It corresponds to each of the ring finger and the little finger. Each of the finger mechanisms 11 to 15 is covered with a finger skin member (not shown) with the joint exposed.

[Explanation about first finger mechanism]
As schematically shown in FIG. 2, the first finger mechanism 11 is connected to a link member fixed to the palm 10 through a CM1 joint, a CM2 joint, an MP joint, and an IP joint in order. The finger link member is provided.

  The CM1 joint and the CM2 joint constitute a “wrist-middle-hand joint mechanism” having a degree of freedom of rotation “2”. The CM1 joint and the CM2 joint rotate about axes that are orthogonal or substantially orthogonal to each other. The MP joint constitutes a “thumb middle metaphalangeal joint mechanism” with a rotational degree of freedom “1”. The IP joint constitutes an “interphalangeal joint mechanism” with a rotational degree of freedom “1”. The CM2 joint, the MP joint, and the IP joint rotate around axes that are parallel or substantially parallel to each other.

  The first finger mechanism 11 bends and stretches due to the rotation of the CM2 joint, the MP joint, and the IP joint, and can perform operations such as bending toward the palm of the palm 10. The CM1 joint rotates the first finger mechanism 11 so as to face the palm side.

[Explanation regarding second to fifth finger mechanisms]
Each of the finger mechanisms 11 to 15 is connected through the MP1 joint, the MP2 joint, the PIP joint, and the DIP joint in order from the link member fixed to the palm 10 as schematically shown in FIG. A plurality of finger link members.

  The MP1 joint and the MP2 joint constitute a “metacarpophalangeal joint mechanism” with a degree of freedom of rotation “2”. The MP1 joint and the MP2 joint rotate about axes that are orthogonal to each other. The PIP joint constitutes a “proximal interphalangeal joint mechanism” having a rotational degree of freedom “1”. The DIP joint constitutes a “distal interphalangeal joint mechanism” having a rotational degree of freedom “1”. The MP2 joint, the PIP joint, and the DIP joint rotate around axes that are parallel or substantially parallel to each other.

  Each of the finger mechanisms 12 to 15 is bent and stretched by the rotation of the MP2 joint, the PIP joint, and the DIP joint, and can be operated, for example, bent toward the palm side of the palm 10. The MP1 joint is capable of performing operations such as swinging each of the finger mechanisms 11 to 15 so that the finger mechanisms 12 to 15 are close to or away from each other, and spreading hands when compared to a human.

[Explanation of sensor]
Each of the finger mechanisms 11 to 15 includes a six-axis force sensor S1 as shown in FIG. 3 and FIG. 4 or FIG. The six-axis force sensor S1 is attached to the fingertip member of each finger mechanism in an inclined posture. The six-axis force sensor S1 measures the six-axis force acting on the fingertip member of each finger mechanism, that is, the translational force in the directions of the three axes (x-axis, y-axis, z-axis) orthogonal to each other and the moment around each axis. To do. Based on the measurement value of the six-axis force output from the six-axis force sensor S1, the strength and direction of the force in each finger mechanism and the direction are controlled.

  At a plurality of locations on the palm side of the palm 10, pressure sensors S <b> 2 that output a signal corresponding to the load or pressure at each location are provided. Similarly, pressure sensors S <b> 2 that output signals corresponding to the load or pressure at each location may be provided at a plurality of locations on the finger pad side of each of the finger mechanisms 11 to 15.

[Explanation on the first type finger mechanism (dexterous finger) and the second type finger mechanism (force finger)]
The five finger mechanisms 11 to 15 are classified into a first type finger mechanism and a second type finger mechanism according to the degree of freedom of active movement. The first finger mechanism 11, the second finger mechanism 12, and the third finger mechanism 13 are classified into “first type finger mechanisms” having a high degree of freedom. The fourth finger mechanism 14 and the fifth finger mechanism 15 are divided into “second type finger mechanisms” having a lower degree of freedom than the first type finger mechanisms.

[Explanation of Type 1 Finger Mechanism]
[Configuration of first finger mechanism]
As shown in FIG. 4, the first finger mechanism 11 divided into the first type of finger mechanism has a CM2 joint rotation axis CM21 (a second rotation axis of the wrist middle-hand joint mechanism). A first driven fluid pressure cylinder 32 (CM2) to be rotated and a second driven fluid pressure cylinder 32 (MP) to rotate the rotation axis MP1 of the MP joint are provided.

  The cylinder body 321 (CM2) of the first driven fluid pressure cylinder 32 (CM2) is a rotation axis of the CM1 joint (second rotation axis of the wrist middle wrist joint), and the palm can be rotated freely. It is supported by the frame 101 of the section 10.

  Thus, by using the cylinder body 321 (CM2) of the first driven fluid pressure cylinder 32 (CM2) as the CM1 joint rotation shaft, the rotation of the first driven fluid pressure cylinder 32 (CM2) and the CM1 joint is performed. Compared with the case where the moving shaft is provided separately, it becomes compact. In addition, the first driven fluid pressure cylinder 32 (CM2) does not swing at all with the rotation of the CM1 joint, and the space for the swing is not required, so that the configuration can be made extremely compact.

  The cylinder body 321 (MP) of the second driven fluid pressure cylinder 32 (MP) is rotatably connected to the first driven fluid pressure cylinder 32 (CM2) via the rotation shaft CM21 of the CM2 joint. .

  A pipe 324 (MP) for supplying a fluid to the cylinder body 321 (MP) of the second driven fluid pressure cylinder 32 (MP) is accommodated in the rotation shaft CM21 of the CM2 joint. Thereby, the piping 324 (MP) does not get in the way when the CM2 joint rotates, and the bending operation of the first finger mechanism 11 can be performed smoothly.

  The IP joint is connected to the MP joint via a connecting member IPL1. The fingertip member is rotatably connected to the rotation shaft IP1 of the IP joint. One end of the connecting member IPL1 is rotatably connected to the rotation shaft MP1 of the MP joint, and the other end is connected to the rotation shaft IP1 of the IP joint.

  Further, a link member IPL2 (link mechanism) is provided between the MP joint and the IP joint. The link member IPL2 connects the cylinder body 321 (MP) of the second driven fluid pressure cylinder 32 (MP) and the support member IPL3 that supports the six-axis force sensor S1 of the fingertip member.

  In the first driven fluid pressure cylinder 32 (CM2), when the fluid is supplied into the cylinder body 321 (CM2), the piston 322 (CM2) slides, and the piston rod 323 (CM2) expands and contracts, so that the CM2 joint Rotate. As a result, the second finger mechanism 12 bends and stretches at the CM2 joint.

  In the second driven fluid pressure cylinder 32 (MP), the piston 322 (MP) slides when the fluid is supplied into the cylinder body 321 (MP), and the piston rod 323 (MP) expands and contracts to cause the MP joint. Rotate. At this time, the MP joint and the IP joint are connected by the connecting member IPL1 and the link member IPL2, thereby following the rotation of the MP joint due to the movement of the second driven fluid pressure cylinder 32 (MP). The IP joint rotates.

  Since the IP joint is configured to be interlocked with the rotation of the MP joint by the second driven fluid pressure cylinder 32 (MP), not only the movement close to the movement of a human finger can be obtained, but also the IP joint A cylinder or the like for driving becomes unnecessary, and the first finger mechanism 11 can be configured to be lightweight.

  With the above configuration, the first finger mechanism 11 extends the piston rods 323 (CM2) and 323 (MP) of the first driven fluid pressure cylinder 32 (CM2) and the second driven fluid pressure cylinder 32 (MP). As a result, the piston rods 323 (CM2) and 323 (MP) are contracted to be extended.

  As shown in FIG. 3, the CM1 joint of the first finger mechanism 11 is caused by a third driven fluid pressure cylinder 32 (CM1) in which the piston rod 323 (CM1) expands and contracts along the arrangement direction of each finger mechanism. It is rotated. The first finger mechanism 11 rotates to the palm side of the palm 10 by extending the piston rod 323 (CM1) of the third driven fluid pressure cylinder 32 (CM1), and the third driven fluid pressure cylinder 32 is rotated. By rotating the piston rod 323 (CM1) of (CM1), the piston rod 323 is rotated in a direction adjacent to the second finger mechanism 12.

  As shown in FIG. 4, the supply of fluid to the cylinder body 321 (CM2) of the first driven fluid pressure cylinder 32 (CM2) is the first driven fluid pressure cylinder which is the rotation shaft of the CM1 joint. This is performed via a fluid path 32 (CM2) 4 formed inside the bearing portion 101 of the cylinder body 321 (CM2) of 32 (CM2). Thereby, the cylinder body 321 (CM2) of the first driven fluid pressure cylinder 32 (CM2) can be smoothly rotated, and the first finger mechanism 11 can be smoothly moved by the rotation of the CM1 joint.

  As shown in FIGS. 3 and 4, coil springs (torsion springs) CM12, CM22, and MP2 are provided in the CM1 joint, the CM2 joint, and the MP joint, respectively. The coil springs MP2 and CM22 of the MP joint and the CM2 joint extend the first finger mechanism 11 in the extending direction. The coil spring CM12 of the CM1 joint is provided so as to surround the outer periphery of the cylinder body 321 (CM2) of the first driven fluid pressure cylinder 32 (CM2), and the first finger mechanism 11 is adjacent to the second finger mechanism 12. Energize in the direction of rotation in the direction of alignment. In other words, the biasing directions of the coil springs CM12, CM22, and MP2 are the piston rods 323 (CM1), 323 (CM2) of the three driven fluid pressure cylinders 32 (CM1), 32 (CM2), and 32 (MP). And the direction of contraction of 323 (MP).

[Configuration of second finger mechanism]
As shown in FIG. 5, the second finger mechanism 12 includes a first driven fluid pressure cylinder 32 (MP2) that rotates the rotation axis MP21 of the MP2 joint (the first rotation axis of the metacarpophalangeal joint). ) And a second driven fluid pressure cylinder 32 (PIP) for rotating the rotation axis PIP1 of the PIP joint.

  The cylinder body 321 (MP2) of the first driven fluid pressure cylinder 32 (MP2) corresponds to a human metacarpal bone, and a rotation axis MP11 of the MP1 joint (a first rotation axis of the metacarpophalangeal joint mechanism). Is supported by the frame 101 (see FIG. 1) of the palm 10 so as to be rotatable. The cylinder body 321 (PIP) of the second driven fluid pressure cylinder 32 (PIP) corresponds to a human proximal phalanx, and the first driven fluid pressure cylinder 32 (MP2) via the rotation axis MP21 of the MP2 joint. Is pivotally connected to the motor.

  A pipe 324 (PIP) for supplying a fluid to the cylinder body 321 (PIP) of the second driven fluid pressure cylinder 32 (PIP) is accommodated in the rotation shaft MP21 of the MP2 joint. Thereby, the piping 324 (PIP) does not get in the way when the MP2 joint is rotated, and the bending operation of the second finger mechanism 12 can be performed smoothly.

  Further, by disposing the cylinder body 321 (PIP) of the second driven fluid pressure cylinder 32 (PIP) along the longitudinal direction of the second finger mechanism 12 between the MP2 joint and the PIP joint, the second finger The mechanism 12 can be configured compactly.

  The DIP joint is connected to the PIP joint via a connecting member DIPL1 corresponding to the human middle phalanx. A support member DIPL2 that supports a six-axis force sensor S1 connected to the fingertip member is rotatably connected to the rotation shaft DIP1 of the DIP joint. One end of the connecting member DIPL1 is rotatably connected to the rotating shaft PIP1 of the PIP joint, and the other end is connected to the rotating shaft DIP1 of the DIP joint.

  Further, a link member DIPL3 (link mechanism) is provided between the PIP joint and the DIP joint. The link member DIPL2 connects the cylinder body 321 (PIP) of the second driven fluid pressure cylinder 32 (PIP) and the support member DIPL2 that supports the six-axis force sensor S1 of the fingertip member.

  In the first driven fluid pressure cylinder 32 (MP2), the piston 322 (MP2) slides when the fluid is supplied into the cylinder body 321 (MP2), and the piston rod 323 (MP2) expands and contracts, thereby causing the MP2 joint. Rotate. Thereby, the 2nd finger mechanism 12 bends and stretches via MP2 joint.

  In the second driven fluid pressure cylinder 32 (PIP), when a fluid is supplied into the cylinder body 321 (PIP), the piston 322 (PIP) slides, and the piston rod 323 (PIP) expands and contracts to expand the PIP joint. Rotate. At this time, since the PIP joint and the DIP joint are connected by the connecting member DIPL1 and the link member DIPL3, the DIP joint follows the rotation of the PIP joint by the second driven fluid pressure cylinder 32 (PIP). Rotate.

  Since the DIP joint is configured to be interlocked with the rotation of the PIP joint by the second driven fluid pressure cylinder 32 (PIP), 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 second finger mechanism 12 can be configured to be lightweight.

  With the above configuration, the second finger mechanism 12 extends the piston rods 323 (MP2) and 323 (PIP) of the first driven fluid pressure cylinder 32 (MP2) and the second driven fluid pressure cylinder 32 (PIP). As a result, the piston rod 323 is bent and the piston rods 323 (MP2) and 323 (PIP) are contracted to be extended.

  As shown in FIG. 3, the MP1 joint of the second finger mechanism 12 is caused by a third driven fluid pressure cylinder 32 (MP1) in which the piston rod 323 (MP1) expands and contracts along the direction of arrangement of the finger mechanisms. It is rotated. The third driven fluid pressure cylinder 32 (MP1) extends the piston rod 323 (MP1), thereby swinging the second finger mechanism 12 in the direction approaching the third finger mechanism 13, and the piston rod 323 (MP1). The second finger mechanism 12 is swung in a direction away from the third finger mechanism 13 by contracting.

  As shown in FIG. 5, each of the MP1 joint, the MP2 joint and the PIP joint is provided with a coil spring (torsion spring) MP12, MP22 and PIP2. The coil springs PIP2 and MP22 of the PIP joint and the MP2 joint urge the second finger mechanism 12 in the extending direction. The coil spring MP12 of the MP1 joint biases the second finger mechanism 12 away from the third finger mechanism 13. In other words, the biasing directions of the coil springs MP12, MP22 and PIP2 are the piston rods 323 (MP1), 323 (MP2) of the three driven fluid pressure cylinders 32 (MP1), 32 (MP2) and 32 (PIP) and The direction is the same as the shrinkage direction of H.323 (PIP).

  The configuration of the second finger mechanism 12 that is the first type finger mechanism has been described in detail above, but the configuration of the third finger mechanism 13 that is the first type finger mechanism is the same as that of the second finger mechanism 12. .

[Configuration of the second type finger mechanism]
Each of the fourth finger mechanism 14 and the fifth finger mechanism 15 divided into the second kind of finger mechanism includes a third driven fluid pressure cylinder 32 (MP1) of the above-described configuration of the second finger mechanism 12. Except for being omitted, the second finger mechanism 12 has the same configuration. In the fourth finger mechanism 14 and the fifth finger mechanism 15, since the third driven fluid pressure cylinder 32 (MP1) is omitted, the MP1 joint freely rotates according to the force operation, and the coil spring of the MP1 joint The MP12 is automatically returned to a predetermined position by urging the MP12. That is, the second type finger mechanism has a lower degree of freedom of active movement than that of the first type finger mechanism.

[Configuration of drive unit]
The configuration of the drive mechanism of the hand 1 will be described. The driving mechanism includes a plurality of driving fluid pressure cylinders (master cylinders) 31 and a plurality of driven fluid pressure cylinders (slave cylinders) 32 (i) (i = CM1, CM2, MP, MP1, MP2) shown in FIG. , PIP) (see FIGS. 3, 4 and 5). A total of 13 drive fluid pressure cylinders 31 are provided corresponding to each of the driven fluid pressure cylinders 32 (i). The driving fluid pressure cylinder 31 and the driven fluid pressure cylinder 32 (i) of the hand 1 are connected to each other via a fluid pressure transmission pipe 33 (pipe). The fluid pressure transmission pipe 33 is flexible enough to change its diameter or cross-sectional area according to the fluid pressure.

  Each of the plurality of driving fluid pressure cylinders 31 is arranged as a unit or distributed in an appropriate location of the robot R (for example, the internal space of the base body B0 or the arm body B2).

  The driving fluid pressure cylinder 31 includes a cylinder body 311 that contains a fluid therein, a piston (master piston) 312 that slides inside the cylinder body 311, and a hollow piston rod 313 that is connected to the piston 312. ing. Furthermore, the driving fluid pressure cylinder 31 includes a ball screw 314 inserted into the piston rod 313 along the axis of the piston rod 313, and a screwing member 315 fixed inside the piston rod 313 and screwed into the ball screw 314. The motor 30 (rotation drive device) that moves the piston rod 313 back and forth via the screwing member 315 by rotating the ball screw 314, and the encoder S3 for detecting the operation amount of the motor 30 are provided. The driving fluid pressure cylinder 31 is provided with a pressure sensor S4 that outputs a signal corresponding to the fluid pressure inside the cylinder body 311.

  The motor 30 rotationally drives the ball screw 314 via a belt 302 hung on pulleys 301 and 303 as rotation transmission means. As a result, the axis of the output shaft 300 of the motor 30 and the piston rod 313 are parallel to each other, and the motor 30 can be provided adjacent to the cylinder body 311 to be compact.

  With this configuration, as schematically shown in FIG. 7, when the master piston 312 is driven forward, the fluid flows out from the driving fluid pressure cylinder 31, and the corresponding driven fluid pressure is supplied via the pipe 33. Each of the finger mechanisms 11 to 15 is driven by the fluid flowing into the cylinder 32 (i) and the piston (slave piston) 322 (i) of the driven fluid pressure cylinder 32 (i) moving forward. On the contrary, when the master piston 312 is driven backward, the fluid flows from the driving fluid pressure cylinder 31 and flows out from the corresponding driven fluid pressure cylinder 32 (i) via the pipe 33 to follow. Each of the finger mechanisms 11 to 15 is driven when the piston 322 (i) of the fluid pressure cylinder 32 (i) moves backward.

[Hand control]
The control device 2 is configured by a computer (configured by a memory such as a CPU, a ROM and a RAM, and a circuit such as an A / D circuit and an I / O circuit). According to the control device 2, the control program is appropriately read from the memory by the CPU, and the operation of the hand 1 is controlled according to the read program.

  The control device 2 controls the movement of each joint mechanism of the arm body B2, the movement of each joint of the leg body B4, and the like by controlling the operation of each of the plurality of actuators 4 mounted on the robot R. The control device 2 controls each movement or force of the finger mechanisms 11 to 15 by controlling the position of the master piston 312.

  The control device 2 includes a first arithmetic processing element 21 and a second arithmetic processing element 22 as shown in FIG.

  The first arithmetic processing element 21 is in contact with an object at each tip of the finger mechanisms 11 to 15 based on an output signal of the six-axis force sensor S1 provided at each tip of the finger mechanisms 11 to 15. Measure the position, the pressure applied to the object and the direction of the pressure. The first arithmetic processing element 21 is based on the output signals and the like of the plurality of pressure sensors S2 arranged at a plurality of positions on the palm side of the palm 10 and the position of the load center in the palm 10 and the palm 10 The load is measured. The first arithmetic processing element 21 is based on the output signals of the encoder S3 and the fluid pressure sensor S4, the position of the piston 322 (i) of the driven fluid pressure cylinder 32 (i), and each of the finger mechanisms 11-15. The rotation angle at each joint i is measured.

  The second arithmetic processing element 22 is configured so that the measurement position of the load center in the palm 10 is a target in a state where the object is held by the hand 1 and is in contact with each of the plurality of finger mechanisms 11 to 15 and the palm 10. The pressure applied to the object from each of the plurality of finger mechanisms 11 to 15 is controlled so that the measurement value of the load applied to the palm portion 10 is included in the target load range while being included in the palm area PA. The second arithmetic processing element 22 controls the rotation angle and thus the position and posture of the finger mechanisms 11 to 15 based on the measurement result of the rotation angle at each joint i of the finger mechanisms 11 to 15. .

  The functions of the robot R, the hand 1 and the control device 2 configured as described above will be described.

[Basic control]
The rotation angles (slave joint angles) θslv at the respective joints of the finger mechanisms 11 to 15 are based on the respective output signals of the encoder S3 and the fluid pressure sensor S4 by the first arithmetic processing element 21, and the relational expressions (1) to (1) to Measured according to (6).

  For the sake of explanation, as shown in FIG. 7, the direction of the swing axis of the finger link member constituting each of the finger mechanisms 11 to 15 is defined as the Z direction, and the forward / backward direction of the driven piston 322 (i) is defined as Consider a Cartesian coordinate system defined as the X direction.

  The rotation angle (slave joint angle) θslv is expressed by the relational expression (1).

θslv = φ + tan ⁻¹ (h / Px) −θ0 (θ0> 0),
^{φ = cos -1 {(Px 2} + (L2) 2 + h 2 - (L1) 2) / (2L (Px 2 + h 2) 1/2)} - θ0 ‥ (1)
“H” is a crank offset, which is an interval in the Y direction between the swing shaft of the finger link member and the rear end swing shaft of the rod 323 (i). “L1” is the distance (rod length) between the rear end swing shaft and the front end swing shaft of the rod 323 (i). “L2” is the distance (crank length) between the swing shaft of the finger link member and the tip swing shaft of the rod 323 (i). The values of the crank offset h, the rod length L1, and the crank length L2 are stored in the memory.

  “Px” is the position (slave piston position) Px of the slave piston 322 (i), and is expressed by the relational expression (2).

Px = P0−Strkslv (2)
“P0” is the reference position of the slave piston 322 (i).

  “Strkslv” is the displacement (slave stroke) of the slave piston 322 (i) from the reference position p0, and is expressed by the relational expression (3).

Strkslv = Strkmst (Smst / Sslv)-StrkOffsetmst + StrkExpslv (3)
“Smst” is a cross-sectional area of the master piston 312. “Sslv” is the cross-sectional area of the slave piston 322 (i). “StrkOffsetmst” is an offset (master stroke offset) of the master piston 312. The cross-sectional areas Smst and Sslv or their ratio (Smst / Sslv) and the value of the master stroke offset StrkOffsetmst are stored in the memory.

  “Strkmst” is the displacement amount (master stroke) of the master piston 312 and can be calculated according to the relational expression (4) based on the rotational position MotPosmst of the motor 30 according to the output signal of the encoder S3.

Strkmst = MotPosmst / Rr (4)
“Rr” is a reduction ratio of the speed reduction mechanism (see FIG. 6) configured by the pulleys 301 and 303 and the belt 302, and is stored in advance in a memory.

  “StrkExpslv” is a slave stroke displacement amount due to a change in cross-sectional area or expansion or contraction of the pipe 33, and can be calculated according to the relational expression (5) based on the cross-sectional area Sslv of the slave piston 323 (i) and the pipe expansion amount Exppip. .

SstrkExpslv = Exppip / Sslv (5)
“Exppip” is the pipe expansion amount (volume change amount), and in addition to the measured fluid pressure Prsact corresponding to the output signal of the fluid pressure sensor S4, the hydraulic target value Prscmd, the coefficient Kpip representing the flexibility of the pipe 33, and Based on the length Lpip of the pipe 33, it is expressed according to the relational expression (6). The hydraulic target value Prscmd, the coefficient Kpip indicating the level of flexibility of the pipe 33, and the length Lpip of the pipe 33 are stored in the memory.

Exppip = (Prscmd-Prsact), Kpip, Lpip (6)
In addition to the slave joint angle θslv measured as described above by the first arithmetic processing element 21, based on the respective output signals of the six-axis force sensor S1 and the pressure sensor S2, as described later, the second arithmetic processing element 22 Each movement or force of the finger mechanisms 11 to 15 is controlled.

[Applied control]
The first arithmetic processing element 21 recognizes information necessary for gripping the object, such as the position and posture of the palm 10 and the position, posture, shape, and size of the object to be gripped using the hand 1. (FIG. 9 / STEP002).

  For controlling the object gripping operation of the robot R, a wrist coordinate system, a hand coordinate system, and an object coordinate system are defined in addition to the robot coordinate system. The “robot coordinate system” is defined to define the position and orientation of the robot R in the world coordinate system. The “wrist coordinate system” is defined, for example, with the representative point of the wrist joint mechanism B25 as the origin and the three rotation axes of the wrist joint mechanism B25 as three orthogonal axes. The “hand coordinate system” has, for example, a point on the hand plane of the palm 10 as an origin, a pair of orthogonal axes parallel to the hand plane as an x-axis and a y-axis, and an axis perpendicular to the hand plane as a z-axis. Is defined as The “object coordinate system” is defined with the representative point of the object as the origin, for example. The positions and postures of the wrist coordinate system and the hand coordinate system with respect to the robot coordinate system are factors that vary depending on the operation of the robot R, such as the bending angles of the shoulder joint mechanism B21, the elbow joint mechanism B23, and the wrist joint mechanism B25, and the memory. Can be calculated according to a forward kinematics calculation method based on certain factors representing the size of the robot R, such as the lengths of the first arm link B22 and the second arm link B22 stored in FIG.

  The position and posture of the palm 10 are measured based on an output signal from a sensor corresponding to the operation state of the robot R, such as a rotary encoder for measuring the bending angle of each joint mechanism of the arm body B2. The position and posture of the palm 10 are recognized by coordinate values or Euler angles in the robot coordinate system. Based on the output signal of an operation state sensor such as a rotary encoder, the positions and postures of the arm R2 and leg B4 of the robot R can also be recognized.

  Image analysis obtained through one or both of the head camera C1 and the waist camera C2 recognizes the position and posture of the base body B0 in a fixed coordinate system (a coordinate system fixed regardless of the movement of the robot R). .

  Based on the operation amount of the motor 30 according to the output signal of the encoder S3, the positions and postures of the tip portions of the finger mechanisms 11 to 15 are recognized. The position of the tip of each finger mechanism is determined by the bending angle of each joint mechanism according to the output signal of the encoder S3, the position of the root of each finger mechanism unchanged in the hand coordinate system, and the phalangeal link of each finger mechanism. Based on the length or the like, it is defined as a position and orientation in the calculated hand coordinate system according to the forward kinematics calculation method.

  The position, posture, shape, and size of the object are recognized based on an image of the peripheral range of the robot R captured by one or both of the head camera C1 and the waist camera C2. The position and orientation of the object are recognized by coordinate values and Euler angles in the robot coordinate system. Since the position and orientation of the object in the robot coordinate system change as the position and orientation of the robot R (for example, the position of the base body B0 and the orientation of the basic frontal plane) change, they are sequentially recognized or measured. Note that the input information may be recognized by the first arithmetic processing element 21 when part or all of the information to be recognized is input to the control device 2 from a terminal device outside the robot R.

  Further, the operation of the actuator 4 is controlled by the second arithmetic processing element 22 based on the position of the object recognized by the first arithmetic processing element 21, so that the spare of the robot R for gripping the object by the hand 1 is reserved. The target operation is controlled (FIG. 9 / STEP004). Specifically, the position and posture of the robot R are adjusted by moving the leg B4 as necessary. In addition, the palm 10 is adjusted to an appropriate position and posture for gripping the object by moving the arm body B2.

  Further, based on the position and posture of the object recognized by the first arithmetic processing element 21, the second arithmetic processing element 22 controls the movements of the finger mechanisms 11 to 15 and the movement of the arm body B2 as necessary. Thus, the object is gripped by the hand 1. Here, a hammer is used as an example as an object. Note that the type of object to be grasped by the hand 1 can be variously changed.

  Specifically, first, the tip of the first finger mechanism 11 abuts on one side of a part of the object (hammer handle), while the tip of each of the second finger mechanism 12 and the third finger mechanism 13 The movements of the first-type finger mechanisms 11 to 13 are controlled so as to contact the other side of a part of the object (FIG. 9 / STEP006). As a result, the object is pinched by the first type finger mechanisms 11 to 13 as shown in FIG.

  Based on the output of the six-axis force sensor S <b> 1, the first arithmetic processing element 21 measures the load and the direction received by each tip of the first type finger mechanisms 11 to 13. Based on the measurement result, the strength and direction of the force for pinching each object of the first type finger mechanisms 11 to 13 can be controlled.

  Further, part or all of the position and posture of the palm 10 and the movements of the first type finger mechanisms 11 to 13 are controlled so as to change the posture of the object (FIG. 9 / STEP008).

As a result, as shown in FIG. 10B, in a state where the object is pinched by the first-type finger mechanisms 11 to 13, a part of the object (hammer head) comes into contact with the placement location. On the other hand, the posture of the object is adjusted so that the other part (hammer handle) is lifted from the mounting position. The posture of the object is changed by driving the arm body B2 so that the wrist coordinate system rotates about one axis of the object coordinate system.
Further, as shown in FIG. 10C, a part of the palm 10 can be brought into contact with the object. The portion of the palm 10 that is first brought into contact with the object is continuous with the plane of the hand in a cross-sectional view, and can detect contact suitably even if there is some error in the object or measurement error in the object. The shape is rounded so that it can be made (see FIG. 10C).

  Further, the movement of the fifth finger mechanism 15 is controlled so that the fifth finger mechanism 15 that is one of the second-type finger mechanisms 14 to 15 is bent to entrain the object (FIG. 9 / STEP010). . As a result, as shown in FIG. 11A, the fifth finger mechanism 15 is made to hold a portion (hammer handle) floating from the place where the object is placed.

  Further, the movements of the first type finger mechanisms 11 to 13 are controlled so that the respective tip portions of the first type finger mechanisms 11 to 13 are separated from the object (FIG. 9 / STEP012). As a result, as shown in FIG. 11B, the first type finger mechanisms 11 to 13 are separated from the object while the object is held by the fifth finger mechanism 15.

  Subsequently, the position, posture or position and posture of the palm portion 10 are controlled so as to increase the area of the contact portion between the palm portion 10 and the object (FIG. 9 / STEP014). Thus, as shown in FIG. 11 (c), the palm 10 is first brought into contact with the object around one axis of the palm coordinate system so that the plane of the hand contacts the object. It is tilted with the part as a fulcrum.

  Further, the movement of the fourth finger mechanism 14 is controlled so that the fourth finger mechanism 14, which is the other finger mechanism among the second type finger mechanisms 14 to 15, is bent and entrains an object (FIG. 9 / STEP016). ). As a result, as shown in FIG. 11 (c), in addition to the fifth finger mechanism 15, the portion (hammer handle) floating from the place where the object is placed is held by the fourth finger mechanism 14. Each of the fourth finger mechanism 14 and the fifth finger mechanism 15 is configured so that the pressure applied to the object from the fourth finger mechanism 14 is gradually increased while the pressure applied to the object from the fifth finger mechanism 15 is gradually decreased. The operation may be controlled.

  And each movement of the 1st finger mechanism 11, the 2nd finger mechanism 12, and the 3rd finger mechanism 13 is controlled so that each of the 1st type finger mechanisms 11-13 bends and entrains an object (Drawing). 9 / STEP018). As a result, as shown in FIG. 11 (d), in addition to the second type finger mechanisms 14 to 15, the first type finger mechanisms 11 to 13 are caused to grip the object.

  Note that the load applied to the palm 10 and the load center position are controlled by controlling the movements of the finger mechanisms 11 to 15 while the object is gripped by the hand 1 as shown in FIG. May be fine-tuned. The load applied to the palm portion 10 and the load center position can be controlled based on the output signals of the load sensors S2 arranged at a plurality of locations on the palm side of the palm portion 10. The first arithmetic processing element 21 measures the load center p0 in the palm 10 and the load f0 applied to the palm 10 based on the output signals of the plurality of pressure sensors S2 arranged on the palm 10. Since this calculation method is described in detail in Japanese Patent Application Laid-Open No. 2007-196372, description thereof is omitted here.

  According to the hand 1 that exhibits the above function, after the object is pinched by the movement of the first type finger mechanisms 11 to 13, the other part is left in contact with the placement location. It is lifted (see FIG. 9 / STEP006 to STEP008, FIGS. 10A and 10B). At this time, since the total mass of the object is not applied to the first type finger mechanisms 11 to 13, it is not necessary to increase the force of the first type finger mechanisms 11 to 13 to the extent that the object is picked up. Therefore, the drive mechanism 3 of the first type finger mechanisms 11 to 13 can be reduced in weight or size.

  Further, in view of the fact that the first-type finger mechanisms 11 to 13 having a relatively high degree of freedom of active motion are suitable for an operation of “pinch” that requires dexterity rather than an operation of “grabbing” an object. The operations of the finger mechanisms 11 to 15 can be appropriately controlled according to their functions or roles. In this configuration, the structure or mechanism related to a part of the finger mechanism is simplified in order to reduce the weight or the size of the hand 1, so that the freedom of active movement of the part of the finger mechanism is reduced. This is particularly significant when designed to be low compared to other finger mechanisms.

  Further, by controlling the position and posture of the palm 10, the contact portion between the palm 10 and the object is expanded (see FIG. 9 / STEP014 and FIG. 11C). At this time, the first-type finger mechanisms 11 to 13 are separated from the object while the object is held by the fifth finger mechanism 15 (see FIG. 9 / STEP012, FIG. 11B). Further, the object is not grasped by the fourth finger mechanism 14 which is one of the second type finger mechanisms (see FIG. 11C). Thereby, each of the finger mechanisms 11 to 14 and the object are not bound to each other's movement or the like, so that the position, posture or position and posture of the palm 20 can be easily changed accordingly.

  Further, a part of the edge of the palm 10 that first contacts the object is formed in a rounded shape that is continuous with the plane of the hand. For this reason, after the palm portion 10 first abuts on the object in the rounded portion, the contact portion between the hand plane and the object continuous with the rounded portion can be increased smoothly. (See FIG. 9 / STEP008, STEP014, FIG. 10 (c), and FIG. 11 (c)).

  Further, by controlling the movement of the plurality of finger mechanisms 11 to 15, the object is gripped by the plurality of finger mechanisms 11 to 15 (FIG. 9 / STEP018). For this reason, an object is firmly grasped in the state which contact | abutted to each of the palm part 10 and the several finger mechanisms 11-15. Then, the object can be stably lifted from the place where the object is held firmly by the hand 1.

  As another embodiment of the present invention, the following object gripping method by the hand 1 may be executed.

  First, the first arithmetic processing element 21 recognizes a heavy part and a light part of an object. “Weight part” means a part having a high mass density across the center of mass of the object. When the object is a hammer, its head (exactly, the portion excluding the vicinity of the base of the head) corresponds to the weight portion. “Lightweight portion” means a portion having a mass density lower than that of the weight portion. When the object is a hammer, the handle (more precisely, the portion including the handle and the base of the head) corresponds to the lightweight portion.

  For example, the image analysis obtained through the head camera C1 recognizes that the object is a hammer having a head and a handle by pattern matching using templates of a plurality of types of objects stored in a database or a storage device. . It is retrieved from a database or a storage device that the head of the hammer corresponds to the heavy weight part and that the hammer handle corresponds to the light weight part.

  Then, based on the recognition result of the first arithmetic processing element 21, the second arithmetic processing element 22 holds the lightweight part (for example, hammer handle) of the object on the first kind of finger mechanisms 11 to 13, and the object becomes the heavy part. The position of the object is changed so that the lightweight portion is lifted from the placement location (see FIGS. 10A and 10B), while abutting on the placement location (eg the table) at the head (for example, the head of the hammer). For example, when the head of the hammer recognized as the heavy part of the object has a columnar shape having an axis orthogonal to the handle of the hammer recognized as the lightweight part of the object, the central axis of the column is the x axis of the object coordinate system. The axis extending in the longitudinal direction of the hammer handle is defined as the y-axis of the object coordinate system.

  According to the control system having the above configuration, a place that can be pinched by the first type finger mechanisms 11 to 13 is selected in view of the deflectability of the mass distribution of the object. The load is reduced. For this reason, the posture of the object changed while being pinched by the first type finger mechanisms 11 to 13 can be stably maintained. Therefore, following this, the object can be lifted stably from its place by firmly grasping the object by the hand 1 as described above.

  Note that the number of finger mechanisms may be three, four, six, etc., as long as there are at least two first-type finger mechanisms for gripping operation and one or more second-type finger mechanisms for gripping operation. It may be changed to an arbitrary number of 3 or more.

  In the above embodiment, the active degree of freedom of movement of the MP1 joint (or CM1 joint) is differentiated, so that the degree of freedom of active movement is differentiated between the first type and second type finger mechanisms. It was done. In addition, the active rotational degree of freedom in any combination of MP1 joint (or CM1 joint), MP2 joint (or CM2 joint), PIP joint (or MP joint) and DIP joint (or IP joint) is differentiated. Thereby, the freedom degree of active movement may be differentiated between the first type and second type finger mechanisms (see FIG. 2).

  When changing the position, posture or position and posture of the palm 10 (see FIG. 9 / STEP014, FIGS. 11B and 11C), some or all of the first-type finger mechanisms 11 to 13 become objects. It may remain in contact. Further, the position, posture, or position and posture of the palm 10 may be changed while the object is grasped by all of the second type finger mechanisms 14 to 15.

  Each finger mechanism of the hand 1 is driven by transmitting the force of a prime mover (electric motor) via a wire, a pulley, and the like, for example, as in the hand described in Japanese Patent Application Laid-Open No. 2003-181787. May be. Also in this case, the plurality of finger mechanisms may be classified into a first type finger mechanism and a second type finger mechanism.

DESCRIPTION OF SYMBOLS 1 ... Hand, 2 ... Control apparatus, 10 ... Palm part of hand, 11 ... 1st finger mechanism, 12 ... 2nd finger mechanism, 13 ... 3rd finger mechanism, 14 ... 4th finger mechanism, 15 ... 5th finger mechanism, 21 ... 1st arithmetic processing element, 22 ... 2nd arithmetic processing element

Claims (9)

A control system for a robot hand comprising a palm part and a plurality of finger mechanisms extending from the palm part,
A first arithmetic processing element for recognizing the position and posture of the palm and the position and posture of the object;
A second arithmetic processing element that controls the position and posture of the palm and the movement of the plurality of finger mechanisms based on the recognition result by the first arithmetic processing element;
The second arithmetic processing element controls the movement of two or more first-type finger mechanisms of the plurality of finger mechanisms, so that the object placed in a certain place is moved to the first-type finger. Pinch the mechanism,
By controlling part or all of the position and posture of the palm and the movement of the first type finger mechanism, the object is held in the state where the object is pinched by the first type finger mechanism. While the portion is in contact with the location, the posture of the object is changed so that the other portion is lifted from the location and a part of the palm is contacted with the object,
By controlling the movement of the second type of finger mechanism that is separated from the first type of finger mechanism among the plurality of finger mechanisms, the second type of finger mechanism floats from the location of the object. Grab the part,
By controlling the position, posture or position and posture of the palm, the area of the contact portion between the palm and the object is increased in a state where the object is held by the second type finger mechanism, And,
A control system that controls movement of the first type of finger mechanism to cause the first type of finger mechanism to grip the object in addition to the second type of finger mechanism. The control system according to claim 1,
The first arithmetic processing element recognizes a division between a weight part having a high mass density across a mass center position in the object and a light part having a mass density lower than the weight part;
The second arithmetic processing element controls the movement of the first type finger mechanism, so that the lightweight portion of the object placed at the location is held on the first type finger mechanism,
By controlling part or all of the position and posture of the palm and the movement of the first type finger mechanism, the lightweight portion of the object is pinched by the first type finger mechanism, While the object is in contact with the part in the weight part, the posture of the object is changed so that the lightweight part is lifted from the part, and the palm part is in contact with the object partially. Control system. The control system according to claim 1 or 2,
The second arithmetic processing element controls the movement of the second type finger mechanism to cause the second type finger mechanism to hold a portion floating from the part of the object, and then By controlling the movement of the kind of finger mechanism, the first kind of finger mechanism is separated from the object in a state where the object is held by the second kind of finger mechanism, A control system characterized by increasing an area of a contact portion between the palm and the object by controlling the posture or the position and the posture. The control system according to claim 3, wherein
There are two or more types of finger mechanisms of the second kind,
The second arithmetic processing element controls the movement of a part of the second type finger mechanism, so that the part of the second type finger mechanism holds the part floating from the part of the object. Thereafter, by controlling the movement of the first type of finger mechanism, the first type of finger mechanism is separated from the object while the object is being held by the partial second type of finger mechanism. In the above, by controlling the movement of the remaining second type finger mechanism, the remaining second type finger mechanism floats from the portion of the object in addition to the partial second type finger mechanism. A control system characterized by grabbing the part. In the control system according to one of claims 1 to 4,
The plurality of finger mechanisms have a difference in the degree of freedom of active movement, and the finger mechanism having a high degree of freedom is used as the first type of finger mechanism to control the movement, and the finger mechanism having a low degree of freedom A control system for controlling the movement of the second-type finger mechanism. The control system according to one of claims 1 to 5,
A part of the edge of the palm is formed in a rounded shape that is continuous with the plane of the hand,
The second arithmetic processing element controls the position and posture of the palm and part or all of the movement of the first type finger mechanism to form a rounded edge of the palm. After the first part is brought into contact with the object, the position, posture or position and posture of the palm is controlled, so that the object is grasped by the second type finger mechanism. A control system that increases an area of a contact portion between the flat surface of the palm and the object.   A robot hand, comprising: a palm portion; a plurality of finger mechanisms extending from the palm portion; and the control system according to claim 1.   A program for controlling a robot hand, which causes a computer to function as the control system according to any one of claims 1 to 6. A control method of a robot hand comprising a palm portion and a plurality of finger mechanisms extending from the palm portion,
Recognizing the position and posture of the palm and the position and posture of the object;
Based on the recognition result, by controlling the movement of two or more first-type finger mechanisms of the plurality of finger mechanisms, the object placed at a certain place is used as the first-type finger mechanism. Pinch,
By controlling part or all of the position and posture of the palm and the movement of the first type finger mechanism, the object is held in the state where the object is pinched by the first type finger mechanism. While the portion is in contact with the location, the posture of the object is changed so that the other portion is lifted from the location and a part of the palm is contacted with the object,
By controlling the movement of the second type of finger mechanism that is separated from the first type of finger mechanism among the plurality of finger mechanisms, the second type of finger mechanism floats from the location of the object. Grab the part,
By controlling the position, posture or position and posture of the palm, the area of the contact portion between the palm and the object is increased in a state where the object is held by the second type finger mechanism, And,
A control method comprising controlling the movement of the first type finger mechanism to cause the first type finger mechanism to grip the object in addition to the second type finger mechanism.

Images