JP2005131733A - Link for walking type robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a link for a walking type robot in which maintenance can be executed in an operable state and by which the risk of causing new failures as a result of executing the maintenance can be avoided. <P>SOLUTION: A link body 70 constituting an outer shape of an upper arm part 7A is integrally molded by casting. An opening 70a, which is closed with a freely attachable/detachable lid body 71, is formed to a part of the link body 70. A motor 120 and a substrate 140 or the like, which can be taken out and put in from the opening 70a, are stored in the link body 70. The motor 120 and the substrate 140 or the like are fixed to the inner wall face of the link body 70 with bolts. When the interior components are subjected to the maintenance, the maintenance is executed from the opening 70a after removing the lid body 71. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a humanoid robot, such as a biped walking type, and more particularly to a structure of a link constituting a movable part such as an arm part or a leg part.

  In recent years, development of this type of walking robot has been remarkable, and there are various types such as a robot that mainly focuses on entertainment, and a work robot that assists and performs work. The humanoid walking robot has an arm and a leg connected to the torso via joints in the same manner as the structure of the human body, and the arm and the leg are housed inside the driving device. And it is moved by the computer etc. which control this drive device (for example, patent documents 1 and 2).

JP-A-7-205070 JP 2002-154077 A

  The movable parts such as arms and legs in the above conventional robot are generally formed by a link body such as a cylindrical casing, and in order to move the movable parts by driving the joints therein. Various interior parts such as a drive device including a motor, a drive transmission system, a control computer, and wiring cables not associated with them are housed. Since the link body can obtain a complicated design, it is often manufactured by casting light alloy or the like, and is generally a pair of halved parts that are divided in the radial direction (divided vertically). It is the structure which unites. With this halved structure, various interior parts are fixed to each halved part and then combined to assemble the link.

By the way, in such a link structure, when performing maintenance such as inspection and repair of interior parts, it is necessary to take a method in which a pair of halved parts are disconnected and the link is divided to expose the interior parts. Absent. Although this method has an advantage that a large work space can be obtained, it is disadvantageous in that the detaching work of the halved parts is complicated, and that the maintenance cannot be completed quickly while the robot is operable. Moreover, since all the interior parts are moved along with the detachment of the halved parts, there is a concern that the maintenance may cause a trouble that a part that does not require repair newly breaks down. Furthermore, a rib may be provided on the joining surface of the halved part, and a screw hole for joining may be formed in the rib. In this form, the weight of the rib causes an increase in the weight of the entire link, and the inside of the rib If there is a protrusion, there is also a problem that the protruding portion reduces the internal mounting volume of the link.
Therefore, an object of the present invention is to provide a link of a walking robot that can perform maintenance in an operable state and can avoid the possibility of causing a new failure by performing the maintenance. .

  The present invention is a link that is directly or indirectly connected to the base of a walking robot, and forms an outer shape of the link, and is a substantially cylindrical integral link body in which an opening is formed in part, A lid that covers the opening and is detachably attached to the link main body, and an interior part that can be inserted into and removed from the link main body through the opening and is fixed to the inner wall surface of the link main body. The link of the present invention is suitable for, for example, one that constitutes a movable part such as an arm part, a leg part, or a hand part of a robot.

  According to the link of the present invention, the maintenance for the interior parts in the link body can be performed from the opening by removing the lid from the link body. Since it is easy to make the robot operable with the lid removed, maintenance of the interior components in the link body can be performed while the robot is still operable. Further, since there is no need to remove the half parts and divide the link as in the prior art, maintenance can be easily performed from this point of view, and there is no possibility that a failure will occur at a new location.

  In the present invention, the lid is preferably made of a transparent material. According to this aspect, it is possible to visually check the interior parts in the link body through the lid body without removing the lid body from the link body. Therefore, there is an advantage that the interior parts can be inspected to some extent. Further, the link main body is not composed of a plurality of parts such as combining the half parts as in the prior art, but the link main body obtains the above-described operations and effects because it is an integral part. As such a link main body, what was shape | molded by casting light alloys etc. from a viewpoint which can obtain a complicated design is good.

  According to the link of the present invention, it is possible to easily perform maintenance of interior parts in the link main body while the robot is operable, and there is no possibility of causing a failure at a new location due to the maintenance. Play.

Hereinafter, an embodiment in which the present invention is applied to an upper arm portion (corresponding to a link in the present invention) of a humanoid robot will be described.
FIG. 1 is an overall view of a humanoid robot R capable of walking on two legs according to an embodiment, where (a) is a front view and (b) is a left side view. The robot R includes a waist 1 and a torso 2. The waist 1 has left and right legs 4 having feet 3 at the tip, and the torso 2 has a head 5 and a hand 6 at the tip. The left and right arm portions 7 are connected to each other. In the following description, the directions such as up / down, left / right, and front / back are the basic postures shown in FIG. 1 unless otherwise noted, that is, the palm of the hand portion 6 faces forward, the hand portion 6 and the arm portion 7 extend straight downward, The part 4 also extends straight and is based on a posture in which the body 2 and the head 5 are facing forward.

  The body 2 is mounted on the waist 1 so as to be horizontally rotated within a predetermined angle range in the left-right direction and tilted at a predetermined angle in the front-rear direction. It is attached to the left / right / front / back. Further, the upper arm portion 7 </ b> A of the arm portion 7 is connected to both shoulders of the body 2 via the shoulder joint portion 11. As shown in FIG. 2 (FIG. 2 shows the left arm portion 7), the arm portion 7 includes an upper arm portion 7A and a lower arm portion 7B connected to the upper arm portion 7A via an elbow joint portion 12, The hand part 6 is connected to the tip of the lower arm part 7B via the wrist joint part 13. The shoulder joint portion 11 has three joint axes extending in the front-rear direction, the left-right direction, and the up-down direction, and the shoulder joint portion 11 itself is attached to the body 2 so as to be rotatable about the joint axis in the left-right direction. . The joint axis in the front-rear direction is rotatably attached to the shoulder joint portion 11, and the joint axis in the vertical direction is attached to the joint axis in the front-rear direction. The upper arm portion 7A is rotatably attached to the vertical joint shaft. The elbow joint portion 12 has a joint axis extending in the left-right direction, and the lower arm portion 7B is swingable about the joint axis. The wrist joint portion 13 has two joint shafts extending in the vertical direction and the left-right direction, is rotatably attached to the tip of the lower arm portion 7B via the vertical joint shaft, and is connected via the left-right joint shaft. The hand portion 6 is swingably attached.

  The left and right legs 4 are connected to the lower end of the waist 1 via the hip joint 14. The hip joint portion 14 is configured such that a joint shaft extending in the left-right direction is attached to a joint shaft extending in the front-rear direction attached to the waist 1 so as to be rotatable around the axis, and the leg portion 4 is attached to the joint shaft in the left-right direction. The upper leg 4A is swingably attached. The leg portion 4 includes an upper leg portion 4A and a lower leg portion 4B connected to the upper leg portion 4A via a knee joint portion 15. The leg portion 3 is connected to the tip of the lower leg portion 4B via an ankle joint portion 16. Are connected. The knee joint portion 15 has a joint axis extending in the left-right direction, and the lower leg portion 4B is swingable about the joint axis. The ankle joint part 16 has two joint axes extending in the left-right direction and the front-rear direction, and the foot part 3 is swingable about these joint axes. In addition, since the joint axis which comprises each said joint part 11-16 is incorporated, it is not illustrated in FIG.

  Each of the movable parts described above, that is, the body 2, the foot 3, the leg 4 (upper leg 4A and lower leg 4B), the head 5, the hand 6, and the arm 7 (upper arm 7A and lower arm 7B). The rotation or swing operation is performed by a drive system using a motor as a drive source and a computer for controlling these drive systems. A battery, which is a power source for the computer and the motor, is housed in an appropriate place. In this case, the computer is housed in the body 2 and the battery is housed in the waist 1. In FIG. 1 and FIG. 2, the leg 4, the arm 7, and the joints 11 to 16 form an appearance design and are covered with a cover for protection, and are driven and actually moved. That is, the driven element is present in the cover. These driven elements are formed by casting with a light alloy such as a magnesium alloy.

  3 and 4 show the shoulder joint 11, the upper arm 7A, and the elbow joint 12 with such a cover removed, and FIG. 5 is a cross-sectional view of this portion. The shoulder joint portion 11 includes a casing 110 as a driven element. The upper surface of the casing 110 in the drawing is opposed to the side surface of the body 2, and the body 2 is centered on a joint axis in the left-right direction (not shown). It is attached so that it can rotate freely. A cylindrical joint shaft 111 in the longitudinal direction is rotatably mounted in the casing 110, and the joint shaft 111 is rotated by a driving device (not shown). As shown in FIG. 5, the joint shaft 111 is integrally formed with a vertical joint shaft 112 extending downward perpendicular to the joint shaft 111, and the harmonic drive type speed reducer is formed on the joint shaft 112. The upper arm portion 7A is connected via the unit 80A. As a result, the arm portion 7 swings about the joint shaft 111 in the front-rear direction. 3 to 5, from the state shown in FIG. 1, the upper arm portion 7 </ b> A is rotated 90 ° around the joint axis 111 to be raised horizontally, and the inner side around the joint axis 112 (FIG. 1B). , Counterclockwise (90 °).

  As shown in FIG. 6, the reduction gear unit 80 </ b> A is rotated via a cross roller bearing 83 on a flex spline support shaft 82 fixed to the joint shaft 112 by a bolt 81, and both the joint shaft 112 and the flex spline support shaft 82. A gear case 84 that is freely supported, a cap 86 that is stacked below the gear case 84 with a circular spline 85 interposed therebetween, and a cover ring 87 that is stacked above the gear case 84 are provided. An input shaft 88 is externally mounted on the flex spline support shaft 82, and a driven pulley 89 (timing pulley) is integrally fixed to the lower end of the input shaft 88. A cap 86 is rotatably supported with respect to the input shaft 88 via an input shaft bearing 90, and a web generator 92 fixed to the input shaft 88 with a bolt 91 and a flex spline support shaft 82 together with the bolt 81. The flex spline 93 is interposed between the circular spline 85 and the input shaft 88.

  As shown in FIG. 4, the upper arm portion 7 </ b> A includes a cylindrical link body 70 whose axial direction extends in the vertical direction as a driven element that is a main body. A rectangular opening 70a having an appropriate size is formed in the side portion of the link body 70, and the opening 70a is closed by a lid 71 that is detachably fixed to the link body 70 with a bolt 72. It has come to come off. The lid 71 has a large number of slits 71a for heat dissipation and weight reduction. Further, as shown in FIGS. 4B and 6, a flange portion 73 is formed at the upper end opening edge of the link body 70. As shown in FIG. 6, the reduction gear unit 80A is fixed to the link body 70 by screwing bolts 94 that pass from the cover ring 87 through the gear case 84, the circular spline 85, and the cap 86 into the flange 73. Thus, the shoulder joint portion 11 and the upper arm portion 7A are connected.

  As shown in FIGS. 4 and 5, the link main body 70 houses a motor 120 that is a drive source for driving the reduction gear unit 80A to rotate the upper arm portion 7A around the joint shaft 112 in the vertical direction. ing. As shown in FIG. 5, the motor 120 has a drive pulley (timing pulley) 121 arranged upward, and its axial direction is parallel to that of the link main body 70. The bolts 123 are fixed to the inner wall surface of the link body 70. In this fixed state, the driving pulley 121 of the motor 120 and the driven pulley 89 of the speed reducer unit 80A are close to each other in a parallel state, and the timing belt 124 is wound around these pulleys 89 and 121.

  When the motor 120 is driven, the rotational force is transmitted to the driven pulley 89 of the speed reducer unit 80A via the timing belt 124, and the input shaft 88 and the flex spline support shaft 82 try to rotate following this. Since the flex spline support shaft 82 is fixed to the joint shaft 111 via the joint shaft 112 of the shoulder joint portion 11, these do not rotate, and the reaction force is transmitted to the motor 120 side so that the motor 120 is fixed. The link main body 70, that is, the upper arm portion 7 </ b> A rotates around the joint shaft 112.

  The link body 70 is formed as a single body by casting a light alloy as described above. As shown in FIGS. 4B and 5, the axial direction is orthogonal to the link body 70 at the lower end. A cylindrical elbow joint shaft holder 74 is integrally formed, and further above (on the boundary between the link main body 70 and the elbow joint shaft holder 74), the axial direction is the same as that of the elbow joint shaft holder 74. A parallel cylindrical motor insertion portion 75 is integrally formed. A motor 130 that swings the lower arm portion 7 </ b> B is inserted into the link main body 70 from the motor insertion portion 75, and the end on the back side in the insertion direction is fixed to the inner wall surface of the link main body 70. A reduction gear unit 80B similar to the reduction gear unit 80A is housed and fixed in the elbow joint shaft holder 74. As shown in FIG. 5, one end of a flex spline support shaft 82b of the reduction gear unit 80B is accommodated. Further, the output shaft 95 is fixed. The lower arm portion 7B is fixed to the output shaft 95. The driving pulley 131 of the motor 130 and the driven pulley 89b of the reduction gear unit 80B are exposed to the outside, and a timing belt 132 is wound around the pulleys 89b and 131.

  When the motor 130 is driven, the rotational force is transmitted to the driven pulley 89b of the speed reducer unit 80B via the timing belt 132, and the input shaft 88b, the flex spline support shaft 82b, the output of the speed reducer unit 80B follows this. The shaft 95 rotates, and thereby the lower arm portion 7B swings.

  As described above, the rotation motor 120 around the vertical axis of the upper arm portion 7A and the swinging motor 130 of the lower arm portion 7B are housed and fixed in the link main body 70 as shown in FIG. As described above, the link main body 70 further accommodates a plurality of motor control boards 140 connected to the computer and wirings (not shown) for the connection. The substrate 140 is fixed with bolts 141 to a boss 76 formed on the inner wall surface of the link body 70 as shown in FIG. The motor 120 and the substrate 140 can be taken in and out of the link main body 70 through the opening 70a, and can be fixed to the inner wall surface of the link main body 70 using the opening 70a. When the fixing operation is completed, the opening 70 a is closed by the lid 71.

  Although the present embodiment has been described above, according to the upper arm portion 7A, it is necessary to perform maintenance such as inspection and repair on the interior parts housed in the link body 70, that is, the motor 120, the board 140, the wiring, and the like. In such a case, the lid 71 can be removed from the link body 70 and the opening 70a can be easily performed. Even when the lid 71 is removed, the robot R can be operated, so that the interior parts in the link body 70 can be maintained while the robot R is still operable. In addition, since there is no need to divide the link body as in the prior art, maintenance can be easily performed from this point of view, and in addition, such a division causes a failure at a new location. There is no risk of malfunction.

  The lid 71 that closes the opening 70a of the link main body 70 is desirably one that increases the strength of the upper arm portion 7A while being fixed to the link main body 70. Further, as shown in FIG. 3B, when a transparent lid 71B is employed, the interior parts in the link body 70 can be visually observed through the lid 71B without removing the lid 71B from the link body 70. Therefore, there is an advantage that the interior parts can be inspected to some extent. In the case of making the lid transparent, it is preferable to form the lid with a material having some strength such as reinforced plastic.

  In the above embodiment, the present invention is applied to the upper arm portion 7A, but it goes without saying that the present invention can be applied to the lower arm portion 7B, the leg portion 4 or the like in the robot R. .

It is (a) front view and (b) left side view of a bipedal walking robot according to an embodiment of the present invention. It is (a) front view of the arm part of the robot, (b) side view, (c) perspective view. (A) is a perspective view of an upper arm part and a shoulder joint part in a state where the cover of the robot is removed, and (b) is a perspective view of a modified example in which a transparent lid is mounted in the same figure. (A) is a perspective view of the state which removed the cover from the link main body of an upper arm part, (b) is an exploded perspective view of (a). It is sectional drawing of the part shown to Fig.3 (a). It is a partial cross section figure of a reduction gear unit.

Explanation of symbols

2 ... trunk (base), 7A ... upper arm (link), 70 ... link body, 70a ... opening,
71, 71B ... lid, 120 ... motor (interior part), 140 ... substrate (interior part),
R: Biped robot.

Claims (4)

A link directly or indirectly connected to the base of the walking robot,
A link body of a substantially cylindrical one that forms the outer shape of the link and has an opening formed in part;
A lid that covers the opening and is detachably attached to the link body;
A walking robot link comprising: an interior part that can be inserted into and removed from the link body through the opening and is fixed to an inner wall surface of the link body.   The walking robot link according to claim 1, wherein the lid is made of a transparent material.   The link of the walking robot according to claim 1 or 2, wherein the link main body is formed into an integral body by casting. The link of the walking robot according to any one of claims 1 to 3, wherein a movable part such as an arm part, a leg part, or a hand part of the robot is configured.

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