1. Technical Field
The present invention relates to a robot, a control apparatus, and a robot system.
2. Related Art
In related art, robots with robot arms are known. In the robot arm, a plurality of arms (arm members) are coupled via joint parts and, as an end effector, e.g. a hand is attached to the arm on the most distal end side (on the most downstream side). The joint parts are driven by motors and the arms rotate by the driving of the joint parts. Then, for example, the robot grasps an object with the hand, moves the object to a predetermined location, and performs predetermined work such as assembly.
As the robot, Patent Document 1 (JP-A-2014-46401) discloses a vertical articulated robot. In the robot described in Patent Document 1, an action of moving a hand with respect to a base to a position different by 180° about a first rotation axis as a rotation axis (rotation axis extending in vertical directions) at the most proximal end side (on the most upstream side) is performed by rotation of a first arm as an arm at the most proximal end side (base side) with respect to the base about the first rotation axis.
In the robot described in Patent Document 1, when the hand is moved to the position different by 180° about the first rotation axis with respect to the base, a large space is required in order to prevent interferences of the robot.
An advantage of some aspects of the invention is to solve at least a part of the problems described above, and can be implemented as the following forms.
A robot according to an aspect of the invention includes an nth (n is an integer equal to or more than one) arm rotatable about an nth rotation axis, and an (n+1)th arm provided on the nth arm to be rotatable about an (n+1)th rotation axis in an axis direction different from an axis direction of the nth rotation axis, wherein a length of the nth arm is longer than a length of the (n+1)th arm, the nth arm and the (n+1)th arm can overlap as seen from the axis direction of the (n+1)th rotation axis, and a shortest time taken for a second action of rotating the (n+1)th arm from a first attitude to a first angle is shorter than a shortest time taken for a first action of rotating the nth arm from the first attitude to the first angle.
According to the robot, the nth arm and the (n+1)th arm can overlap as seen from the axis direction of the (n+1)th rotation axis, and a space for preventing interferences of the robot may be made smaller. Further, the robot according to the aspect of the invention is adapted so that the shortest time of the (n+1)th arm may be shorter than the shortest time of the nth arm when the nth arm and the (n+1)th arm are respectively independently rotated to the same angle. Accordingly, in the action in which the respective arms are simultaneously moved, when the (n+1)th arm is rotated more largely than the nth arm, the respective arms may be rotated without excessive degradation of the performances of the respective arms.
In the robot according to the aspect of the invention, it is preferable that a maximum velocity of the (n+1)th arm is larger than a maximum velocity of the nth arm.
With this configuration, in the action in which the respective arms are simultaneously moved, when the (n+1)th arm is rotated more largely than the nth arm, the respective arms may be rotated without excessive degradation of the performances of the respective arms.
In the robot according to the aspect of the invention, it is preferable that a maximum acceleration of the (n+1)th arm is larger than a maximum acceleration of the nth arm.
With this configuration, in the action in which the respective arms are simultaneously moved, when the (n+1)th arm is rotated more largely than the nth arm, the respective arms may be rotated without excessive degradation of the performances of the respective arms.
In the robot according to the aspect of the invention, it is preferable that the second action is performed via a state in which the nth arm and the (n+1)th arm overlap as seen from the axis direction of the (n+1)th rotation axis.
As described above, according to the robot of the aspect of the invention, the action via the state in which the nth arm and the (n+1)th arm overlap may be performed. In the action, the (n+1)th arm is rotated more largely than the nth arm for reduction of the space for preventing the interferences of the robot. Accordingly, as described above, the shortest time of the (n+1)th arm is set to be shorter than the shortest time of the nth arm, and thereby, also, in the action, the respective arms may be rotated without excessive degradation of the performances of the respective arms.
In the robot according to the aspect of the invention, it is preferable that an (n+2)th arm is provided on the (n+1)th arm and rotatable about an (n+2)th rotation axis parallel to the (n+1)th rotation axis, wherein the (n+1)th arm and the (n+2)th arm can overlap as seen from the axis direction of the (n+1)th rotation axis.
With this configuration, for example, in the robot having a hand on the distal end of the arm, the movable range of the hand may be made wider.
In the robot according to the aspect of the invention, it is preferable that a shortest time taken for a third action of rotating the (n+2)th arm from the first attitude to the first angle is shorter than a shortest time taken for the second action of the (n+1)th arm.
As described above, the shortest time of the (n+2)th arm may be shorter than the shortest time of the (n+1)th arm when the (n+1)th arm and the (n+2)th arm are respectively independently rotated to the same angle. Accordingly, in the action in which the (n+1)th arm and the (n+2)th arm are simultaneously moved, when (n+2)th arm is rotated more largely than the (n+1)th arm, the (n+1)th arm and the (n+2)th arm may be rotated without excessive degradation of the performances of the (n+1)th arm and the (n+2)th arm.
In the robot according to the aspect of the invention, it is preferable that the third action is performed via a state in which the (n+2)th arm and the (n+1)th arm overlap as seen from the axis direction of the (n+1)th rotation axis.
As described above, according to the robot of the aspect of the invention, the action via the state in which the (n+1)th arm and the (n+2)th arm overlap may be performed. In the action, the (n+2)th arm is rotated more largely than the (n+1)th arm for reduction of the space for preventing the interferences of the robot. Accordingly, as described above, the shortest time of the (n+2)th arm is set to be shorter than the shortest time of the (n+1)th arm, and thereby, also, in the action, the (n+1)th arm and the (n+2)th arm may be rotated without excessive degradation of the performances of the (n+1)th arm and the (n+2)th arm.
In the robot according to the aspect of the invention, it is preferable that, supposing that a ratio of a velocity of the nth arm to the maximum velocity of the nth arm when the nth arm and the (n+1)th arm are simultaneously rotated is RV1 and a ratio of a velocity of the (n+1)th arm to the maximum velocity of the (n+1)th arm when the nth arm and the (n+1)th arm are simultaneously rotated is RV2, a relationship of 0.8≦RV2/RV1<1.0 is satisfied.
With this configuration, in the action in which the nth arm and the (n+1)th arm are simultaneously moved, when the (n+1)th arm is moved more than the nth arm, the respective arms may be rotated without excessive degradation of the performances of the nth arm and the (n+1)th arm.
In the robot according to the aspect of the invention, it is preferable that, supposing that a ratio of an acceleration of the nth arm to a maximum acceleration of the nth arm when the nth arm and the (n+1)th arm are simultaneously rotated is RA1 and a ratio of an acceleration of the (n+1)th arm to a maximum acceleration of the (n+1)th arm when the nth arm and the (n+1)th arm are simultaneously rotated is RA2, a relationship of 0.8≦RA2/RA1<1.0 is satisfied.
With this configuration, in the action in which the nth arm and the (n+1)th arm are simultaneously moved, when the (n+1)th arm is moved more than the nth arm, the respective arms may be moved without excessive degradation of the performances of the nth arm and the (n+1)th arm. Further, the adjustment of the acceleration may be easier than the adjustment of the velocity.
In the robot according to the aspect of the invention, it is preferable that a base is provided on a proximal end side of the nth arm (n is one).
With this configuration, the nth arm and the (n+1)th arm may be rotated with respect to the base.
A control apparatus according to an aspect of the invention controls actions of the robot according to the aspect of the invention.
With this configuration, the control apparatus controlling actions of the robot that may reduce the space for preventing the interferences of the robot may be provided.
A robot system according to an aspect of the invention includes the robot according to the aspect of the invention and a control apparatus controlling actions of the robot.
With this configuration, the robot system including the robot that may reduce the space for preventing the interferences of the robot and the control apparatus controlling actions thereof may be provided.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
As below, a robot, a control apparatus, and a robot system according to the invention will be explained in detail based on preferred embodiments shown in the accompanying drawings.
Hereinafter, for convenience of explanation, the upside in
A robot system 100 shown in
The robot 1 shown in
As shown in
For example, an end effector such as a hand 91 that grasps a precision apparatus, a part, or the like may be detachably attached to the distal end of the sixth arm 17.
The robot 1 is a vertical articulated (six-axis) robot in which the base 11, the first arm 12, the second arm 13, the third arm 14, the fourth arm 15, the fifth arm 16, and the sixth arm 17 are sequentially coupled from the proximal end side toward the distal end side.
As below, the first arm 12, the second arm 13, the third arm 14, the fourth arm 15, the fifth arm 16, and the sixth arm 17 will be respectively also referred to as “arm”. The first drive source 401, the second drive source 402, the third drive source 403, the fourth drive source 4O4, the fifth drive source 405, and the sixth drive source 406 will be respectively also referred to as “drive source (drive unit)”.
Base
As shown in
Note that, in the embodiment, a plate-like flange 111 provided in the lower part of the base 11 is fixed to the attachment surface 102, however, the part fixed to the attachment surface 102 is not limited to that. For example, the part may be an upper surface of the base 11. The fixing method is not particularly limited, but e.g. a fixing method using a plurality of bolts or the like may be employed.
The location to which the base 11 is fixed is not limited to the ceiling of the installation space, but may be e.g. a wall, a floor, a ground of the installation space.
The robot arm 10 shown in
The first arm 12 has a bending shape. The first arm 12 has a first portion 121 connected to the base 11 and extending downward in the vertical direction from the base 11, a second portion 122 extending in the horizontal direction from the lower end of the first portion 121, a third portion 123 provided on an opposite end of the second portion 122 to the first portion 121 and extending in the vertical direction, and a fourth portion 124 extending in the horizontal direction from the distal end of the third portion 123. These first portion 121, second portion 122, third portion 123, and fourth portion 124 are integrally formed. Further, the second portion 122 and the third portion 123 are nearly orthogonal (crossing) as seen from the near side of the paper surface of
The second arm 13 has a longitudinal shape and is connected to the distal end of the first arm 12 (the opposite end of the fourth portion 124 to the third portion 123).
The third arm 14 has a longitudinal shape and is connected to the opposite end of the second arm 13 to the end to which the first arm 12 is connected.
The fourth arm 15 is connected to the opposite end of the third arm 14 to the end to which the second arm 13 is connected. The fourth arm 15 has a pair of supporting portions 151, 152 opposed to each other. The supporting portions 151, 152 are used for connection to the fifth arm 16.
The fifth arm 16 is located between the supporting portions 151, 152 and connected to the supporting portions 151, 152, and thereby, coupled to the fourth arm 15. Note that the structure of the fourth arm 15 is not limited to the structure, but may have one supporting portion (cantilever).
The sixth arm 17 has a flat plate shape and is connected to the distal end of the fifth arm 16. Further, the hand 91 is detachably attached to the distal end of the sixth arm 17 (the opposite end to the fifth arm 16). The hand 91 includes, but not particularly limited to, e.g. aconfiguration having a plurality of finger portions (fingers).
Each of the exteriors of the above described respective arms 12 to 17 may be formed by a single member or a plurality of members.
Next, referring to
As shown in
The joint 171 has a mechanism that rotatably supports the first arm 12 coupled to the base 11 with respect to the base 11. Thereby, the first arm 12 is rotatable around the first rotation axis (nth rotation axis) O1 in parallel to the vertical direction (about the first rotation axis O1) with respect to the base 11. Further, the first rotation axis O1 is a rotation axis on the most upstream side of the robot 1. The rotation about the first rotation axis O1 is performed by driving of the first drive source 401 having a motor 401M. Further, the first drive source 401 is driven by the motor 401M and a cable (not shown), and the motor 401M is controlled by the control apparatus 5 via a motor driver 301 electrically connected thereto. Note that the first drive source 401 may be adapted to transmit the drive power from the motor 401M by a reducer (not shown) provided with the motor 401M, or the reducer may be omitted.
The first arm 12 and the second arm 13 are coupled via a joint (connecting part) 172. The joint 172 has a mechanism that rotatably supports one of the first arm 12 and the second arm 13 coupled to each other with respect to the other. Thereby, the second arm 13 is rotatable around the second rotation axis O2 ((n+1)th rotation axis) in parallel to the horizontal direction (about the second rotation axis O2) with respect to the first arm12. The second rotation axis O2 is orthogonal to the first rotation axis O1. The rotation about the second rotation axis O2 is performed by driving of the second drive source 402 having a motor 402M. Further, the second drive source 402 is driven by the motor 402M and a cable (not shown), and the motor 402M is controlled by the control apparatus 5 via a motor driver 302 electrically connected thereto. Note that the second drive source 402 may be adapted to transmit the drive power from the motor 402M by a reducer (not shown) provided with the motor 402M, or the reducer may be omitted. The second rotation axis O2 may be parallel to the axis orthogonal to the first rotation axis O1, or the second rotation axis O2 may be different in axis direction from the first rotation axis O1, not orthogonal thereto.
The second arm 13 and the third arm 14 are coupled via a joint (connecting part) 173. The joint 173 has a mechanism that rotatably supports one of the second arm 13 and the third arm 14 coupled to each other with respect to the other. Thereby, the third arm 14 is rotatable around a third rotation axis O3 in parallel to the horizontal direction (about the third rotation axis O3) with respect to the second arm 13. The third rotation axis O3 is parallel to the second rotation axis O2. The rotation about the third rotation axis O3 is performed by driving of the third drive source 403. Further, the third drive source 403 is driven by a motor 403M and a cable (not shown), and the motor 403M is controlled by the control apparatus 5 via a motor driver 303 electrically connected thereto. Note that the third drive source 403 may be adapted to transmit the drive power from the motor 403M by a reducer (not shown) provided with the motor 403M, or the reducer may be omitted.
The third arm 14 and the fourth arm 15 are coupled via a joint (connecting part) 174. The joint 174 has a mechanism that rotatably supports one of the third arm 14 and the fourth arm 15 coupled to each other with respect to the other. Thereby, the fourth arm 15 is rotatable around a fourth rotation axis O4 in parallel to the center axis direction of the third arm 14 (about the fourth rotation axis O4) with respect to the third arm 14. The fourth rotation axis O4 is orthogonal to the third rotation axis O3. The rotation about the fourth rotation axis O4 is performed by driving of the fourth drive source 4O4. Further, the fourth drive source 4O4 is driven by a motor 4O4M and a cable (not shown), and the motor 4O4M is controlled by the control apparatus 5 via a motor driver 3O4 electrically connected thereto. Note that the fourth drive source 4O4 may be adapted to transmit the drive power from the motor 4O4M by a reducer (not shown) provided with the motor 4O4M, or the reducer may be omitted. The fourth rotation axis O4 may be parallel to the axis orthogonal to the third rotation axis O3, or the fourth rotation axis O4 may be different in axis direction from the third rotation axis O3, not orthogonal thereto.
The fourth arm 15 and the fifth arm 16 are coupled via a joint (connecting part) 175. The joint 175 has a mechanism that rotatably supports one of the fourth arm 15 and the fifth arm 16 coupled to each other with respect to the other. Thereby, the fifth arm 16 is rotatable around a fifth rotation axis O5 orthogonal to the center axis direction of the fourth arm 15 (about the fifth rotation axis O5) with respect to the fourth arm 15. The fifth rotation axis O5 is orthogonal to the fourth rotation axis O4. The rotation about the fifth rotation axis O5 is performed by driving of the fifth drive source 405. Further, the fifth drive source 405 is driven by a motor 405M and a cable (not shown), and the motor 405M is controlled by the control apparatus 5 via a motor driver 305 electrically connected thereto. Note that the fifth drive source 405 may be adapted to transmit the drive power from the motor 405M by a reducer (not shown) provided with the motor 405M, or the reducer may be omitted. The fifth rotation axis O5 may be parallel to the axis orthogonal to the fourth rotation axis O4, or the fifth rotation axis O5 may be different in axis direction from the fourth rotation axis O4, not orthogonal thereto.
The fifth arm 16 and the sixth arm 17 are coupled via a joint (connecting part) 176. The joint 176 has a mechanism that rotatably supports one of the fifth arm 16 and the sixth arm 17 coupled to each other with respect to the other. Thereby, the sixth arm 17 is rotatable around a sixth rotation axis O6 (about the sixth rotation axis O6) with respect to the fifth arm 16. The sixth rotation axis O6 is orthogonal to the fifth rotation axis O5. The rotation about the sixth rotation axis O6 is performed by driving of the sixth drive source 406. Further, the sixth drive source 406 is driven by a motor 406M and a cable (not shown), and the motor 406M is controlled by the control apparatus 5 via a motor driver 306 electrically connected thereto. Note that the sixth drive source 406 may be adapted to transmit the drive power from the motor 406M by a reducer (not shown) provided with the motor 406M, or the reducer may be omitted. The fifth rotation axis O5 may be parallel to the axis orthogonal to the fourth rotation axis O4, the sixth rotation axis O6 may be parallel to the axis orthogonal to the fifth rotation axis O5, or the sixth rotation axis O6 may be different in axis direction from the fifth rotation axis O5, not orthogonal thereto.
The robot 1 driving in the above described manner controls the actions of the arms 12 to 17 etc. while grasping a precision apparatus, a part, or the like with the hand 91 connected to the distal end of the sixth arm 17, and thereby, may perform respective work of carrying the precision apparatus, the part, etc. The driving of the hand 91 is controlled by the control apparatus 5.
The control apparatus 5 shown in
In the embodiment, the control apparatus 5 is provided separately from the robot 1, however, may be provided inside of the robot 1.
As above, the basic configuration of the robot 1 is briefly explained. The robot 1 having the configuration is the vertical articulated robot having the six (plurality of) arms 12 to 17 as described above, and thereby, the drive range is wider and higher workability may be exerted.
Further, as described above, in the robot 1, the proximal end side of the first arm 12 is attached to the base 11, and thereby, the respective arms 12 to 17 may be rotated with respect to the base 11. Furthermore, the robot 1 is of the suspended type with the base 11 attached to the ceiling 101, and the joint 171 as the connecting part between the base 11 and the first arm 12 is located above the joint 172 as the connecting part between the first arm 12 and the second arm 13 in the vertical direction. Accordingly, the work range of the robot 1 below the robot 1 in the vertical direction may be made wider.
Next, referring to
In the following explanation, the third arm 14, the fourth arm 15, the fifth arm 16, and the sixth arm 17 are considered in a condition that they are stretched straight, in other words, in a condition that the fourth rotation axis O4 and the sixth rotation axis O6 are aligned or in parallel as shown in
First, as shown in
Here, the length L1 of the first arm 12 is a distance between the second rotation axis O2 and a center line 611 extending in the leftward and rightward directions in
Further, as shown in
Here, the angle θ formed by the first arm 12 and the second arm 13 is an angle formed by a straight line passing through the second rotation axis O2 and the third rotation axis O3 (a center axis of the second arm 13 as seen from the axis direction of the second rotation axis O2) 621 and the first rotation axis O1 as seen from the axis direction of the second rotation axis O2 (see
Furthermore, as shown in
As shown in
Here, the total length L3 of the third arm 14, the fourth arm 15, the fifth arm 16, and the sixth arm 17 is a distance between the third rotation axis O3 and the distal end of the sixth arm 17 as seen from the axis direction of the second rotation axis O2 (see
In the robot 1 having the robot arm 10, the above described relationships are satisfied, and thereby, as shown in
By the driving of the robot arm 10, as shown in
Specifically, as shown in
Further, similarly, the height of the installation space of the robot 1 (the height in the vertical direction) may be made lower than the height of related art, specifically, e.g. 80% of the height of related art or less.
The action of moving the hand 91 as shown by the arrows 64 can be performed, and, when the hand 91 is moved to a position different by 180° about the first rotation axis O1, for example, the first arm 12 may not be rotated or the rotation angle (amount of rotation) of the first arm 12 may be made smaller. The rotation angle of the first arm 12 about the first rotation axis O1 is made smaller, and thereby, the rotation of the first arm 12 having portions protruding outward from the base 11 (the second portion 122, the third portion 123, and the fourth portion 124) may be made smaller, and interferences of the robot 1 with peripherals may be reduced.
Further, the action of moving the hand 91 as shown by the arrows 64 can be performed and the movement of the robot 1 may be reduced, and thereby, the robot 1 may be efficiently driven. Accordingly, the takt time may be shortened and the work efficiency may be improved. In addition, the distal end of the robot arm 10 may be linearly moved and the movement of the robot 1 may be easily grasped.
Here, to execute the above described action of moving the hand 91 of the robot 1 (the distal end of the robot arm 10) to a position different by 180° about the first rotation axis O1 by simply rotating the first arm 12 about the first rotation axis O1 like the robot of related art, the robot 1 may interfere with the peripherals, and thus, it is necessary to teach the robot 1 an evacuation point for avoiding the interference. For example, in the case where, when only the first arm 12 is rotated to 90° about the first rotation axis O1, the robot 1 also interferes with the peripherals, it is necessary to teach the robot 1 many evacuation points not to interfere with the peripherals. As described above, in the robot of related art, it is necessary to teach many evacuation points, and an enormous number of evacuation points are necessary. Therefore, a lot of effort and time are taken for teaching.
On the other hand, in the robot 1, when the action of moving the hand 91 to a position different by 180° about the first rotation axis O1 is executed, the number of regions and portions that may interfere is very small and the number of evacuation points to teach may be reduced and effort and time which are taken for teaching may be reduced. That is, in the robot 1, the number of evacuation points to teach may be about ⅓ of that of the robot of related art, and teaching is dramatically easier.
In the robot 1, a region (part) 105 of the third arm 14 and the fourth arm 15 surrounded by a dashed-two dotted line on the right in
Objects that can be mounted on the region 105 include e.g. a controller for controlling driving of a sensor of a hand, a hand eye camera, or the like, a solenoid valve for a suction mechanism, etc.
As a specific example, for example, when a suction mechanism is provided on the hand, if a solenoid valve or the like is provided in the region 105, the solenoid valve causes no obstruction when the robot 1 is driven. The region 105 is highly convenient as described above.
The above described robot 1 may move the distal end of the robot arm 10 to a target position by e.g. an operation (PTP operation) by PTP (Point To Point) control.
The PTP operation is an operation by control of designating (teaching) several points (teaching points) from the present position to the target position, however, not designating (restricting) paths of the distal end of the robot arm 10 from certain points to other points and attitudes of the respective arms 12 to 17 in the paths.
Generally, the PTP operation simultaneously moves the respective arms 12 to 17 so that the movement times of the respective arms 12 to 17 may be nearly the same.
As below, the PTP operation of the robot 1 will be explained with reference to
In the PTP operation of the robot 1, as described above, the points (teaching points) are designated, however, via points and attitudes to the points are not designated. Accordingly, for example, in the case where the point A and the point B different from each other are set and the distal end of the robot arm 10 is moved from the point A to the point B, it is considered that the robot 1 changes from a state in which the distal end of the robot arm 10 is located at the point Ain the attitude as shown in
In the movement to the attitude of the robot 1 as shown in
On the other hand, in the movement to the attitude of the robot 1 as shown in
As described above, in the robot 1, the interferences of the robot 1 with peripherals may be less in the action with the smaller rotation angle θ1 (the action that satisfies the relationship of rotation angle θ1<rotation angle θ2) like the movement to the attitude of the robot 1 shown in
Here, as shown in
However, as described above, in the PTP operation, the first arm 12 and the second arm 13 are moved nearly simultaneously so that the respective movement times of the first arm 12 and the second arm 13 may be the same. Accordingly, to make the arrival time TX1 of the first arm 12 equal to the arrival time TX2 of the second arm 13, the first arm 12 rotates at a velocity VX1 as shown by a solid line in
Now, in the robot 1 of the embodiment, as shown in
Note that
As shown in
That is, a ratio RV1 of the velocity V1 to the maximum velocity V1MAX (the velocity V1 of the first arm 12 in the PTP operation) may be made smaller than the above described ratio RX (see
Particularly, as described above, the robot 1 selects the action of the first arm 12 with the smaller rotation angle θ1 at an action via a state in which the first arm 12 and the second arm 13 overlap as seen from the second rotation axis O2. Accordingly, in the robot 1 that performs the action via the state in which the first arm 12 and the second arm 13 overlap, the shortest times T1, T2 (the maximum velocities V1MAX, V2MAX) are set as described above, and thereby, the effect that the first arm 12 and the second arm 13 may be rotated without excessive degradation of the performances of the first arm 12 and the second arm 13 may be especially pronouncedly exerted.
Note that, in the above description, the first arm 12 is rotated at the velocity V1 lower than the maximum velocity V1MAX according to the shortest time T2 of the second arm 13, however, the velocity V2 of the second arm 13 may be rotated at the velocity V2 lower than the maximum velocity V2MAX as appropriate.
Further, supposing that a ratio of the velocity V1 (the velocity of the first arm 12 in the PTP operation) to the maximum velocity V1MAX is RV1 and a ratio of the velocity V2 (the velocity of the second arm 13 in the PTP operation) to the maximum velocity V2MAX is RV2, the ratio RV1 and the ratio RV2 preferably satisfy a relationship of 0.8≦RV2/RV1<1.0 and more preferably satisfy a relationship of 0.9≦RV2/RV1<1.0.
As described above, when the ratio RV1 and the ratio RV2 are nearly equal, the first arm 12 and the second arm 13 may be rotated without excessive degradation of the respective performances of the first arm 12 and the second arm 13. That is, if the shortest times T1, T2 (the maximum velocities V1MAX, V2MAX) are set to satisfy the above described relationships, excessive degradation of the respective performances of the first arm 12 and the second arm 13 may be avoided. Further, the rotations of the first arm 12 and the second arm 13 at the ratio RV1 and the ratio RV2 are particularly effective at the above described action via the state in which the first arm 12 and the second arm 13 overlap.
Furthermore, in the robot 1, the shortest time T3 (the maximum velocity V3MAX) of the third arm 14 is set in addition to the above described settings of the shortest times T1, T2 (the maximum velocities V1MAX, V2MAX).
In the robot 1, like the above described relationships between the first arm 12 and the second arm 13, the interferences of the robot 1 with peripherals may be less in an action in which the rotation angle θ2 of the second arm 13 is smaller than the rotation angle θ3 of the third arm 14 compared in an action in which the rotation angle θ2 of the second arm 13 is larger than the rotation angle θ3 of the third arm 14.
Accordingly, in the robot 1, as shown in
Note that
As shown in
That is, a ratio RV2 of the velocity V2 (the velocity of the second arm 13 in the PTP operation) to the maximum velocity V2MAX may be made smaller than the above described ratio RX (see
Particularly, as described above, the robot 1 selects the action of the second arm 13 with the smaller rotation angle θ2 at an action via a state in which the second arm 13 and the third arm 14 overlap as seen from the second rotation axis O2. Accordingly, in the robot 1 that performs the action via the state in which the second arm 13 and the third arm 14 overlap, the shortest times T2, T3 (the maximum velocities V2MAX, V3MAX) are set as described above, and thereby, the effect that the second arm 13 and the third arm 14 may be rotated without excessive degradation of the performances of the second arm 13 and the third arm 14 may be especially pronouncedly exerted.
Note that, in the embodiment, the second arm 13 is rotated at the velocity V2 lower than the maximum velocity V2MAX according to the shortest time T3 of the third arm 14, however, the velocity V3 of the third arm 14 may be rotated at the velocity V3 lower than the maximum velocity V3MAX as appropriate.
Further, supposing that a ratio of the velocity V2 (the velocity of the second arm 13 in the PTP operation) to the maximum velocity V2MAX is RV2 and a ratio of the velocity V3 (the velocity of the third arm 14 in the PTP operation) to the maximum velocity V3MAX is RV3, the ratio RV2 and the ratio RV3 preferably satisfy a relationship of 0.8≦RV3/RV2<1.0 and more preferably satisfy a relationship of 0.9≦RV3/RV2<1.0.
As described above, when the ratio RV2 and the ratio RV3 are nearly equal, the second arm 13 and the third arm 14 may be rotated without excessive degradation of the respective performances of the second arm 13 and the third arm 14. That is, if the shortest times T2, T3 (the maximum velocities V2MAX, V3MAX) are set to satisfy the above described relationships, degradation of the respective performances of the second arm 13 and the third arm 14 may be avoided. Further, the rotations of the second arm 13 and the third arm 14 at the ratio RV2 and the ratio RV3 are particularly effective at the above described action via the state in which the second arm 13 and the third arm 14 overlap.
As described above, in the robot 1, the maximum velocity V2MAX of the second arm 13 is set to be larger than the maximum velocity V1MAX of the first arm 12. Further, the maximum velocity V3MAX of the third arm 14 is set to be larger than the maximum velocity V2MAX of the second arm 13. Therefore, in the robot 1, the first arm 12, the second arm 13, and the third arm 14 satisfy a relationship of maximum velocity V1MAX<maximum velocity V2MAX<maximum velocity V3MAX. That is, in the robot 1, the first arm 12, the second arm 13, and the third arm 14 satisfy a relationship of shortest time T3<shortest time T2<shortest time T1.
According to the robot 1, in the PTP operation, even when the third arm 14, the second arm 13, and the first arm 12 are rotated to the larger rotation angles in this order, the first arm 12, the second arm 13, and the third arm 14 may be rotated without excessive degradation of the performances of the first arm 12, the second arm 13, and the third arm 14.
Further, in the above description, the robot 1 is set (adapted) so that the maximum velocity V2MAX may be higher than the maximum velocity V1MAX, however, as shown in
Even in the configuration, the respective arms 12, 13 may be moved without excessive degradation of the respective performances of the first arm 12 and the second arm 13. Further, adjustment of the acceleration may be easily performed by e.g. adjustment of a reduction ratio of a reducer or adjustment of a control command.
Similarly, the maximum acceleration of the third arm 14 may be set to be larger than the maximum acceleration of the second arm 13.
Further, supposing that an acceleration of the first arm 12 in the PTP operation is A1 and the maximum acceleration of the first arm 12 is A1MAX, and an acceleration of the second arm 13 in the PTP operation is A2 and the maximum acceleration of the second arm 13 is A2MAX, a ratio RA1 of the acceleration A1 to the maximum acceleration A1MAX and a ratio RA2 of the acceleration A2 to the maximum acceleration A2MAX preferably satisfy a relationship of 0.8≦RA2/RA1<1.0 and more preferably satisfy a relationship of 0.9≦RA2/RA1<1.0.
Thereby, like the above described relationships of the ratios RV1, RV2, the first arm 12 and the second arm 13 may be rotated without excessive degradation of the respective performances of the first arm 12 and the second arm 13.
Similarly, supposing that an acceleration of the third arm 14 in the PTP operation is A3 and the maximum acceleration of the third arm 14 is A3MAX, a ratio RA3 of the acceleration A3 to the maximumacceleration A3MAX and the ratio RA2 preferably satisfy a relationship of 0.8≦RA3/RA2<1.0 and more preferably satisfy a relationship of 0.9≦RA3/RA2<1.0.
Furthermore, the above described settings of the maximum velocities V1MAX, V2MAX, V3MAX or the maximum accelerations A1MAX, A2MAX, A3MAX of the respective arms 12 to 14 may be made using capacities of motors, reduction ratios of reducers, etc. singly or in combination.
As above, the robot, the control apparatus, and the robot system according to the invention are explained according to the illustrated embodiments, however, the invention is not limited to those and the configurations of the respective parts may be replaced by arbitrary configurations having the same functions. Further, other arbitrary configurations may be added. Furthermore, the invention may include a combination of two or more arbitrary configurations (features) of the above described respective embodiments.
In the above described embodiments, the number of rotation axes of the robot arm of the robot is six, however, the invention is not limited to that. The number of rotation axes of the robot arm may be e.g. two, three, four, five, or seven or more. Further, in the above described embodiments, the number of arms of the robot is six, however, the invention is not limited to that. The number of arms of the robot may be e.g. two, three, four, five, or seven or more.
Furthermore, in the above described embodiments, the number of robot arms of the robot is one, however, the invention is not limited to that. The number of robot arms of the robot may be e.g. two or more. That is, the robot may be e.g. a multi-arm robot including a dual-arm robot.
In the above described embodiments, regarding conditions (relationships) of an nth rotation axis, an nth arm, an (n+1)th rotation axis, and an (n+1)th arm, the case where n is one, i.e., the case where the first rotation axis, the first arm, the second rotation axis, and the second arm satisfy the conditions is explained, however, the invention is not limited to that. The n may be an integer equal to or more than one, and the same conditions as those in the case where n is one may be satisfied with respect to an arbitrary integer equal to or more than one. Therefore, for example, the case where n is two, i.e., the case where the second rotation axis, the second arm, the third rotation axis, and the third arm may satisfy the same conditions as those in the case where n is one, the case where n is three, i.e., the case where the third rotation axis, the third arm, the fourth rotation axis, and the fourth arm may satisfy the same conditions as those in the case where n is one, the case where n is four, i.e., the case where the fourth rotation axis, the fourth arm, the fifth rotation axis, and the fifth arm may satisfy the same conditions as those in the case where n is one, or, the case where n is five, i.e., the case where the fifth rotation axis, the fifth arm, the sixth rotation axis, and the sixth arm may satisfy the same conditions as those in the case where n is one.
The entire disclosure of Japanese Patent Application No. 2015-175431, filed Sep. 7, 2015 is expressly incorporated by reference herein.
Number | Date | Country | Kind |
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2015-175431 | Sep 2015 | JP | national |