Patent Publication Number: US-9895800-B2

Title: Robot, robot control device, and robot system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/197,692 filed Mar. 5, 2014, which claims priority to Japanese Patent Application No. 2013-118670 filed Jun. 5, 2013, both of which are hereby expressly incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a robot, a robot control device, and a robot system. 
     2. Related Art 
     In a robot described in JP-A-2011-136395, a six-axis sensor which detects accelerations in the directions of an X axis, a Y axis, and a Z axis orthogonal to each other and accelerations around the X axis, the Y axis, and the Z axis is provided in a front end portion, that is, a sixth link on a front-most end side. A vibrational component of angular velocity around an intended axis is obtained for each link on the basis of the detection result of the six-axis sensor. As such, control for suppressing vibration is performed. The vibrational component of the angular velocity of the link is called “torsional angular velocity”, “vibrational angular velocity”, or the like. 
     In the robot described in JP-A-2011-136395, since the posture of the six-axis sensor changes with the motion of the robot, it is necessary to perform coordinate axis transformation or the like, called Jacobi&#39;s transformation, from the detection result of the six-axis sensor, and to obtain the vibrational component of the angular velocity of each link. Moreover, it is necessary to perform computation in conformity with the rotation angle of a motor which changes every moment. 
     Since complicated and enormous computation processing is required, there is a problem in that a control device which has a high-performance and an expensive CPU (Central Processing Unit) or the like is required. This causes an increase in cost. 
     Also, since the complicated and enormous computation processing is required, there is a problem in that a computation error is likely to occur. If such an error occurs, it is not possible to sufficiently suppress vibration due to the computation error. 
     SUMMARY 
     An advantage of some aspects of the invention is that it provides a robot, a robot control device, and a robot system capable of suppressing vibration easily and reliably. 
     An aspect of the invention is directed to a robot including a base, a first arm which is connected to the base rotatably around a first rotating axis as a rotation center, a second arm which is connected to the first arm rotatably around a second rotating axis, which is an axis orthogonal to the first rotating axis or an axis parallel to the axis orthogonal to the first rotating axis, as a rotation center, a third arm which is connected to the second arm rotatably around a third rotating axis, which is an axis parallel to the second rotating axis, as a rotation center, a first angular velocity sensor which is provided in the first arm, and a second angular velocity sensor which is provided in the third arm, in which the angle between a detection axis of the first angular velocity sensor and the first rotating axis is a predetermined first angle, and the angle between a detection axis of the second angular velocity sensor and the third rotating axis is a predetermined second angle. 
     With this configuration, it is possible to suppress vibration easily and reliably. 
     That is, first, the angular velocity of the first arm can be detected by the first angular velocity sensor. Since the third rotating axis is parallel to the second rotating axis, the angular velocity of the third arm including the rotation amount of the second arm can be detected by the second angular velocity sensor. Then, it is possible to suppress vibration on the basis of these detection results. 
     Since the angular velocity of the third arm including the rotation amount of the second arm is detected by the second angular velocity sensor instead of the angular velocity of the second arm, it is possible to suppress vibration more reliably. 
     It is possible to reduce the number of angular velocity sensors, to reduce cost, and to simplify the configuration of the robot compared to a case where an angular velocity sensor is also provided in the second arm. 
     In the robot according to the aspect of the invention, it is preferable that the first angle is 0°, and the second angle is 0°. 
     With this configuration, even if the posture of the robot changes, the detection axis of the angular velocity of the first angular velocity sensor is constant. For this reason, it is not necessary to correct the angular velocity of the first arm detected by the first angular velocity sensor with the direction of the first angular velocity sensor. 
     Since the third rotating axis and the second rotating axis are orthogonal to the first rotating axis or are parallel to the axis orthogonal to the first rotating axis, even if the posture of the robot changes, for example, even if the first arm rotates or the second arm rotates, the detection axis of the angular velocity of the second angular velocity sensor is constant. For this reason, it is not necessary to correct the angular velocity of the third arm detected by the second angular velocity sensor with the direction of the second angular velocity sensor. 
     Accordingly, complicated and enormous computation is not required. Therefore, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot. 
     In the robot according to the aspect of the invention, it is preferable that the first angle is greater than 0° and equal to or smaller than 15°, and the second angle is greater than 0° and equal to or smaller than 15°. 
     With this configuration, a computation error is less likely to occur, and it is possible to suppress vibration reliably. 
     In the robot according to the aspect of the invention, it is preferable that the first angular velocity sensor is an angular velocity sensor which detects the angular velocity around the first rotating axis of the first arm, and the second angular velocity sensor is an angular velocity sensor which detects a composite angular velocity of the angular velocity around the second rotating axis of the second arm and the angular velocity around the third rotating axis of the third arm. 
     With this configuration, it is possible to detect the angular velocity of the first arm and the angular velocity of the third arm with high precision. 
     In the robot according to the aspect of the invention, it is preferable that an “a” axis orthogonal to the first rotating axis and a “b” axis orthogonal to both the first rotating axis and the a axis are set, and when the angle between the detection axis of the first angular velocity sensor and the first rotating axis around the a axis is α 1 , the angle between the detection axis of the first angular velocity sensor and the first rotating axis around the b axis is β 1 , and the angular velocity which is detected by the first angular velocity sensor with the rotation around the first rotating axis of the first arm is ω 1 , the angular velocity around the first rotating axis of the first arm is output as ω 1  cos α 1  cos β 1 . 
     With this configuration, complicated and enormous computation is not required, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot. 
     In the robot according to the aspect of the invention, it is preferable that a “c” axis orthogonal to the second rotating axis and a “d” axis orthogonal to both the second rotating axis and the c axis are set, and when the angle between the detection axis of the second angular velocity sensor and the second rotating axis around the c axis is α 2 , the angle between the detection axis of the second angular velocity sensor and the second rotating axis around the d axis is β 2 , and the angular velocity which is detected by the second angular velocity sensor with the rotation around the second rotating axis of the third arm is ω 2 , the angular velocity around the second rotating axis of the second arm is output as ω 2  cos α 2  cos β 2 . 
     With this configuration, complicated and enormous computation is not required, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot. 
     In the robot according to the aspect of the invention, it is preferable that the second angular velocity sensor is arranged in the first arm through a first posture adjustment mechanism, and the second angular velocity sensor is arranged in the third arm through a second posture adjustment mechanism. 
     With this configuration, it is possible to adjust the posture of each of the first and second angular velocity sensors. 
     It is preferable that the robot according to the aspect of the invention further includes a first angular velocity sensor unit having a first housing, and the first angular velocity sensor and a circuit unit which are provided in the first housing, the circuit unit AD converting and transmitting a signal output from the first angular velocity sensor, and a second angular velocity sensor unit having a second housing, and the second angular velocity sensor and a circuit unit which are provided in the second housing, the circuit unit AD converting and transmitting a signal output from the second angular velocity sensor, in which the first angular velocity sensor unit is provided in the first arm, and the second angular velocity sensor unit is provided in the third arm. 
     With this configuration, it is possible to simplify the configuration compared to a case where the circuit unit is provided separately. 
     In the robot according to the aspect of the invention, it is preferable that the appearance of each of the first housing and the second housing is a rectangular parallelepiped, the detection axis of the first angular velocity sensor matches (is aligned with) the normal to the largest surface of the rectangular parallelepiped of the first housing, and the detection axis of the second angular velocity sensor matches (is aligned with) the normal to the largest surface of the rectangular parallelepiped of the second housing. 
     With this configuration, it is possible to allow the directions of the detection axis of the first angular velocity sensor and the detection axis of the second angular velocity sensor to be recognized easily and reliably, and to allow the first angular velocity sensor and the second angular velocity sensor to take an appropriate posture easily. 
     In the robot according to the aspect of the invention, it is preferable that the first housing has an attachment portion to be attached to the first arm in a corner portion of the first housing, and the second housing has an attachment portion to be attached to the third arm in a corner portion of the second housing. 
     With this configuration, it is possible to attach the first angular velocity sensor unit to the first arm reliably, and to attach the second angular velocity sensor unit to the third arm reliably. 
     It is preferable that the robot according to the aspect of the invention further includes a fixing member which is conductive and fixes the attachment portion of the first housing to the first arm, the circuit unit of the first angular velocity sensor unit being grounded to the first arm by the fixing member, and a fixing member which is conductive and fixes the attachment portion of the second housing to the third arm, the circuit unit of the second angular velocity sensor unit being grounded to the third arm by the fixing member. 
     With this configuration, it is possible to reduce the number of components and to simplify the configuration. 
     In the robot according to the aspect of the invention, it is preferable that the first arm has a housing and an arm-side attachment portion formed integrally with the housing, and the first angular velocity sensor unit is attached directly to the arm-side attachment portion. 
     With this configuration, it is possible to allow the first angular velocity sensor unit to rotate integrally with the first arm reliably. 
     In the robot according to the aspect of the invention, it is preferable that the third arm has a housing and an arm-side attachment portion formed integrally with the housing, and the second angular velocity sensor unit is attached directly to the arm-side attachment portion. 
     With this configuration, it is possible to allow the second angular velocity sensor unit to rotate integrally with the third arm reliably. 
     It is preferable that the robot according to the aspect of the invention further includes a cable which is provided in the first arm and supplies power to the robot, in which the first angular velocity sensor is arranged in an end portion of the first arm on an opposite side to the cable. 
     With this configuration, it is possible to prevent the first angular velocity sensor from being affected by noise from the cable, and to prevent a circuit or a wiring on the first angular velocity sensor side from being short-circuited by the cable. 
     It is preferable that the robot according to the aspect of the invention further includes a cable which is provided in the third arm and supplies power to the robot, in which the second angular velocity sensor is arranged in an end portion of the third arm on an opposite side to the cable. 
     With this configuration, it is possible to prevent the second angular velocity sensor from being affected by noise from the cable, and to prevent a circuit or a wiring on the second angular velocity sensor side from being short-circuited by the cable. 
     It is preferable that the robot according to the aspect of the invention further includes a fourth arm which is connected to the third arm rotatably around a fourth rotating axis, which is an axis orthogonal to the third rotating axis or an axis parallel to the axis orthogonal to the third rotating axis, as a rotation center, a fifth arm which is connected to the fourth arm rotatably around a fifth rotating axis, which is an axis orthogonal to the fourth rotating axis or an axis parallel to the axis orthogonal to the fourth rotating axis, as a rotation center, and a sixth arm which is connected to the fifth arm rotatably around a sixth rotating axis, which is an axis orthogonal to the fifth rotating axis or an axis parallel to the axis orthogonal to the fifth rotating axis, as a rotation center. 
     With this configuration, a more complicated motion can be easily performed. 
     In the robot according to the aspect of the invention, it is preferable that the first rotating axis matches (is aligned with) the normal to an installation surface of the base. 
     With this configuration, it is possible to easily control the robot. 
     Another aspect of the invention is directed to a robot including a base, a first arm which is connected to the base rotatably around a first rotating axis as a rotation center, a second arm which is connected to the first arm rotatably around a second rotating axis, which is an axis orthogonal to the first rotating axis or an axis parallel to the axis orthogonal to the first rotating axis, as a rotation center, a third arm which is connected to the second arm rotatably around a third rotating axis, which is an axis parallel to the second rotating axis, as a rotation center, a first angular velocity sensor which is provided in the first arm, and a second angular velocity sensor which is provided in the second arm, in which the angle between a detection axis of the first angular velocity sensor and the first rotating axis is a predetermined first angle, and the angle between a detection axis of the second angular velocity sensor and the third rotating axis is a predetermined second angle. 
     With this configuration, it is possible to suppress vibration easily and reliably. 
     That is, first, the angular velocity of the first arm can be detected by the first angular velocity sensor. Since the third rotating axis is parallel to the second rotating axis, the angular velocity of the third arm including the rotation amount of the second arm can be detected by the second angular velocity sensor. Then, it is possible to suppress vibration on the basis of these detection results. 
     Since the angular velocity of the third arm including the rotation amount of the second arm is detected by the second angular velocity sensor instead of the angular velocity of the second arm, it is possible to suppress vibration more reliably. 
     It is possible to reduce the number of angular velocity sensors, to reduce cost, and to simplify the configuration of the robot compared to a case where an angular velocity sensor is also provided in the second arm. 
     Still another aspect of the invention is directed to a robot control device which controls the actuation of a robot, in which the robot includes a base, a first arm which is connected to the base rotatably around a first rotating axis as a rotation center, a second arm which is connected to the first arm rotatably around a second rotating axis, which is an axis orthogonal to the first rotating axis or an axis parallel to the axis orthogonal to the first rotating axis, as a rotation center, a third arm which is connected to the second arm rotatably around a third rotating axis, which is an axis parallel to the second rotating axis, as a rotation center, a first angular velocity sensor which is provided in the first arm, and a second angular velocity sensor which is provided in the third arm, the angle between a detection axis of the first angular velocity sensor and the first rotating axis is a predetermined first angle, the angle between a detection axis of the second angular velocity sensor and the third rotating axis is a predetermined second angle, and the robot control device includes a receiving unit which receives a first signal output from the first angular velocity sensor provided in the first arm and a second signal output from the second angular velocity sensor provided in the third arm, a calculation unit which obtains a vibrational component of the first arm and a vibrational component of the third arm on the basis of the first signal and the second signal received by the receiving unit, and a control unit which controls the actuation of the robot on the basis of the vibrational component of the first arm and the vibrational component of the third arm obtained by the calculation unit. 
     With this configuration, it is possible to suppress vibration easily and reliably. 
     That is, first, the vibrational component of the angular velocity of the first arm can be obtained by the calculation unit on the basis of the angular velocity of the first arm detected by the first angular velocity sensor. Since the third rotating axis is parallel to the second rotating axis, the vibrational component of the angular velocity of the third arm including the vibrational component of the angular velocity of the second arm can be obtained by the calculation unit on the basis of the angular velocity of the third arm including the rotation amount of the second arm detected by the second angular velocity sensor. Then, it is possible to suppress vibration on the basis of the vibrational component of the angular velocity of the first arm and the vibrational component of the angular velocity of the third arm. 
     Since the vibrational component of the angular velocity of the third arm including the vibrational component of the angular velocity of the second arm is obtained by the calculation unit on the basis of the angular velocity of the third arm including the rotation amount of the second arm detected by the second angular velocity sensor, instead of the vibrational component of the angular velocity of only the second arm, it is possible to suppress vibration more reliably. 
     Yet another aspect of the invention is directed to a robot system including the robot according to the aspect of the invention, and a robot control device which controls the actuation of the robot. 
     With this configuration, it is possible to suppress vibration easily and reliably. 
     That is, first, the angular velocity of the first arm can be detected by the first angular velocity sensor. Since the third rotating axis is parallel to the second rotating axis, the angular velocity of the third arm including the rotation amount of the second arm can be detected by the second angular velocity sensor. Then, it is possible to suppress vibration on the basis of these detection results. 
     Since the angular velocity of the third arm including the rotation amount of the second arm is detected by the second angular velocity sensor instead of the angular velocity of the second arm, it is possible to suppress vibration more reliably. 
     It is possible to reduce the number of angular velocity sensors, to reduce cost, and to simplify the configuration of the robot compared to a case where an angular velocity sensor is also provided in the second arm. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is a perspective view when a robot according to a first embodiment of the invention is viewed from a front side. 
         FIG. 2  is a perspective view when the robot shown in  FIG. 1  is viewed from a rear side. 
         FIG. 3  is a schematic view of the robot shown in  FIG. 1 . 
         FIG. 4  is a block diagram of a part of a robot system having the robot shown in  FIG. 1 . 
         FIG. 5  is a front view of the robot shown in  FIG. 1 . 
         FIG. 6  is a diagram showing the vicinity of a first angular velocity sensor in a first arm of the robot shown in  FIG. 1 . 
         FIG. 7  is a diagram showing the vicinity of a speed reducer in a third arm of the robot shown in  FIG. 1 . 
         FIG. 8  is a sectional view of a first angular velocity sensor unit of the robot shown in  FIG. 1 . 
         FIG. 9  is a plan view of a gyro element in an angular velocity sensor. 
         FIGS. 10A and 10B  are diagrams showing the actuation of the gyro element shown in  FIG. 9 . 
         FIGS. 11A and 11B  are diagrams showing the slope between a detection axis of an angular velocity sensor and a rotating axis of an arm. 
         FIG. 12  is a block diagram of a part of the robot shown in  FIG. 1 . 
         FIG. 13  is a block diagram of a part of the robot shown in  FIG. 1 . 
         FIG. 14  is a block diagram of a part of the robot shown in  FIG. 1 . 
         FIG. 15  is a block diagram of a part of the robot shown in  FIG. 1 . 
         FIG. 16  is a block diagram of a part of the robot shown in  FIG. 1 . 
         FIG. 17  is a perspective view showing a position adjustment member in a robot according to a second embodiment of the invention. 
         FIG. 18  is a perspective view showing a second arm of a robot according to a third embodiment of the invention. 
         FIG. 19  is a diagram showing the slope between a detection axis of an angular velocity sensor and a rotating axis of an arm. 
         FIG. 20  is a block diagram of a part of the robot shown in  FIG. 18 . 
         FIG. 21  is a block diagram of a part of the robot shown in  FIG. 18 . 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, a robot, a robot control device, and a robot system according to the invention will be described in detail on the basis of a preferred embodiment shown in the accompanying drawings. 
     First Embodiment 
       FIG. 1  is a perspective view when a robot according to a first embodiment of the invention is viewed from a front side.  FIG. 2  is a perspective view when the robot shown in  FIG. 1  is viewed from a rear side.  FIG. 3  is a schematic view of the robot shown in  FIG. 1 .  FIG. 4  is a block diagram of apart of a robot system having the robot shown in  FIG. 1 .  FIG. 5  is a front view of the robot shown in  FIG. 1 .  FIG. 6  is a diagram showing the vicinity of a first angular velocity sensor in a first arm of the robot shown in  FIG. 1 .  FIG. 7  is a diagram showing the vicinity of a speed reducer in a third arm of the robot shown in  FIG. 1 .  FIG. 8  is a sectional view of a first angular velocity sensor unit of the robot shown in  FIG. 1 . FIG.  9  is a plan view of a gyro element in an angular velocity sensor.  FIGS. 10A and 10B  are diagrams showing the actuation of the gyro element shown in  FIG. 9 .  FIGS. 11A and 11B  are diagrams showing the slope between a detection axis of an angular velocity sensor and a rotating axis of an arm.  FIGS. 12 to 16  are block diagrams of a part of the robot shown in  FIG. 1 . 
     Hereinafter, for convenience of description, the upper side in  FIGS. 1 to 3 and 5 to 8  is referred to as “up” or “upward”, and the lower side is referred to as “down” or “downward”. The base side in  FIGS. 1 to 3 and 5 to 7  is referred to as “base end”, and the opposite side is referred to as “front end”. In  FIG. 8 , reference numerals of the respective units of a second angular velocity sensor unit are written in parentheses corresponding to a first angular velocity sensor unit, and a diagram of the second angular velocity sensor unit is omitted. 
     A robot system (industrial robot system)  10  shown in  FIGS. 1 to 4  can be used in, for example, a manufacturing process for manufacturing precision equipment, such as a wristwatch, and has a robot (industrial robot)  1 , and a robot control device (control unit)  20  (see  FIG. 4 ) which controls the actuation of the robot  1 . The robot  1  and the robot control device  20  are electrically connected together. The robot control device  20  can be constituted by, for example, a personal computer (PC) embedded with a CPU (Central Processing Unit) or the like. The robot control device  20  will be described below in detail. 
     The robot  1  includes a base  11 , four arms (links)  12 ,  13 ,  14 , and  15 , a wrist (link)  16 , and six driving sources  401 ,  402 ,  403 ,  404 ,  405 , and  406 . The robot  1  is a vertical articulated (six-axis) robot (robot body) in which the base  11 , the arms  12 ,  13 ,  14 , and  15 , and the wrist  16  are connected in this order from the base end to the front end. In the vertical articulated robot, the base  11 , the arms  12  to  15 , and the wrist  16  may be collectively referred to as “arm”, the arm  12  may be referred to as a “first arm”, the arm  13  may be referred to as a “second arm”, the arm  14  may be referred to as a “third arm”, the arm  15  may be referred to as a “fourth arm”, and the wrist  16  may be referred to as “fifth arm and sixth arm”, separately. In this embodiment, the wrist  16  has the fifth arm and the sixth arm. An end effector or the like can be attached to the wrist  16 . 
     The arms  12  to  15  and the wrist  16  are supported to be separately displaceable with respect to the base  11 . Although the length of each of the arms  12  to  15  and the wrist is not particularly limited, and in the illustrated configuration, the length of each of the first arm  12 , the second arm  13 , and the fourth arm  15  is set to be longer than the third arm  14  and the wrist  16 . 
     The base  11  and the first arm  12  are connected together through a joint  171 . The first arm  12  has a first rotating axis O 1  parallel to a vertical direction as a rotation center with respect to the base  11 , and is rotatable around the first rotating axis O 1 . The first rotating axis O 1  matches (is aligned with) the normal to a top surface of a floor  101  which is an installation surface of the base  11 . The rotation around the first rotating axis O 1  is performed by driving of the first driving source  401  having a motor  401 M. The first driving source  401  is driven by the motor  401 M and a cable (not shown), and the motor  401 M is controlled by the robot control device  20  through a motor driver  301  electrically connected to the motor  401 M (see  FIG. 4 ). Although the first driving source  401  may be configured to transmit a driving force from the motor  401 M by a speed reducer (not shown) provided along with the motor  401 M or a speed reducer may be omitted, in this embodiment, the first driving source  401  has a speed reducer. 
     The first arm  12  and the second arm  13  are connected together through a joint  172 . The second arm  13  is rotatable around a second rotating axis O 2  as an axial center parallel to a horizontal direction with respect to the first arm  12 . The second rotating axis O 2  is orthogonal to the first rotating axis O 1 . The rotation around the second rotating axis O 2  is performed by driving of the second driving source  402  having a motor  402 M. The second driving source  402  is driven by the motor  402 M and a cable (not shown), and the motor  402 M is controlled by the robot control device  20  through a motor driver  302  electrically connected to the motor  402 M (see  FIG. 4 ). Although the second driving source  402  may be configured to transmit a driving force from the motor  402 M by a speed reducer  45  (see  FIG. 5 ) provided along with the motor  402 M or a speed reducer may be omitted, in this embodiment, the second driving source  402  has the speed reducer  45 . The second rotating axis O 2  may be parallel to an axis orthogonal to the first rotating axis O 1 . 
     The second arm  13  and the third arm  14  are connected together through a joint  173 . The third arm  14  has a third rotating axis O 3  parallel to the horizontal direction as a rotation center with respect to the second arm  13 , and is rotatable around the third rotating axis O 3 . The third rotating axis O 3  is parallel to the second rotating axis O 2 . The rotation around the third rotating axis O 3  is performed by driving of the third driving source  403 . The third driving source  403  is driven by a motor  403 M and a cable (not shown), and the motor  403 M is controlled by the robot control device  20  through a motor driver  303  electrically connected to the motor  403 M (see  FIG. 4 ). Although the third driving source  403  may be configured to transmit a driving force from the motor  403 M by the speed reducer  45  provided along with the motor  403 M or a speed reducer may be omitted, in this embodiment, the third driving source  403  has the speed reducer  45 . 
     The third arm  14  and the fourth arm  15  are connected together through a joint  174 . The fourth arm  15  has a fourth rotating axis O 4  parallel to a center axis direction of the third arm  14  as a rotation center with respect to the third arm  14  (base  11 ), and is rotatable around the fourth rotating axis O 4 . The fourth rotating axis O 4  is orthogonal to the third rotating axis O 3 . The rotation around the fourth rotating axis O 4  is performed by driving of the fourth driving source  404 . The fourth driving source  404  is driven by a motor  404 M and a cable (not shown), and the motor  404 M is controlled by the robot control device  20  through a motor driver  304  electrically connected to the motor  404 M (see  FIG. 4 ). Although the fourth driving source  404  may be configured to transmit a driving force from the motor  404 M by a speed reducer (not shown) provided along with the motor  404 M or a speed reducer may be omitted, in this embodiment, the fourth driving source  404  has a speed reducer. The fourth rotating axis O 4  may be parallel to an axis orthogonal to the third rotating axis O 3 . 
     The fourth arm  15  and the wrist  16  are connected together through a joint  175 . The wrist  16  has a fifth rotating axis O 5  parallel to the horizontal direction as a rotation center with respect to the fourth arm  15 , and is rotatable around the fifth rotating axis O 5 . The fifth rotating axis O 5  is orthogonal to the fourth rotating axis O 4 . The rotation around the fifth rotating axis O 5  is performed by driving of the fifth driving source  405 . The fifth driving source  405  is driven by a motor  405 M and a cable (not shown), and the motor  405 M is controlled by the robot control device  20  through a motor driver  305  electrically connected to the motor  405 M (see  FIG. 4 ). Although the fifth driving source  405  may be configured to transmit a driving force from the motor  405 M by a speed reducer (not shown) provided along with the motor  405 M or a speed reducer may be omitted, in this embodiment, the fifth driving source  405  has a speed reducer. The wrist  16  has a sixth rotating axis O 6  perpendicular to the fifth rotating axis O 5  as a rotation center through a joint  176 , and is rotatable around the sixth rotating axis O 6 . The sixth rotating axis O 6  is orthogonal to the fifth rotating axis O 5 . The rotation around the sixth rotating axis O 6  is performed by driving of the sixth driving source  406 . The sixth driving source  406  is driven by a motor  406 M and a cable (not shown), and the motor  406 M is controlled by the robot control device  20  through a motor driver  306  electrically connected to the motor  406 M (see  FIG. 4 ). Although the sixth driving source  406  may be configured to transmit a driving force from the motor  406 M by a speed reducer (not shown) provided along with the motor  406 M or a speed reducer may be omitted, in this embodiment, the sixth driving source  406  has a speed reducer. The fifth rotating axis O 5  may be parallel to an axis orthogonal to the fourth rotating axis O 4 , and the sixth rotating axis O 6  may be parallel to an axis orthogonal to the fifth rotating axis O 5 . 
     As shown in  FIG. 6 , the first arm  12  is provided with a first angular velocity sensor  31 , that is, a first angular velocity sensor unit  71  having the first angular velocity sensor  31  is provided. The angular velocity around the first rotating axis O 1  of the first arm  12  is detected by the first angular velocity sensor  31 . 
     As shown in  FIG. 7 , the third arm  14  is provided with a second angular velocity sensor  32 , that is, a second angular velocity sensor unit  72  having the second angular velocity sensor  32 . The angular velocity (the angular velocity of the third arm  14  including the rotation amount of the second arm  13 , and the same applies to the below) around the second rotating axis O 2  of the third arm  14  is detected by the second angular velocity sensor  32 . 
     The first angular velocity sensor  31  and the second angular velocity sensor  32  are not particularly limited, and for example, a gyro sensor or the like may be used. 
     In the robot  1 , vibration of the first arm  12 , the second arm  13 , and the third arm  14  is suppressed, thereby suppressing vibration of the entire robot  1 . However, in order to suppress vibration of the first arm  12 , the second arm  13 , and the third arm  14 , instead of providing the angular velocity sensor in each of the first arm  12 , the second arm  13 , and the third arm  14 , as described above, the first angular velocity sensor  31  and the second angular velocity sensor  32  are respectively provided only in the first arm  12  and the third arm  14 , and the actuation of the driving sources  401  and  402  is controlled on the basis of the detection results of the first angular velocity sensor  31  and the second angular velocity sensor  32 . Accordingly, it is possible to reduce the number of angular velocity sensors, to reduce cost, and to simplify the circuit configuration compared to a case where the angular velocity sensor is provided in each of the first arm  12 , the second arm  13 , and the third arm  14 . Since the angular velocity of the third arm  14  including the rotation amount of the second arm  13 , instead of the angular velocity of the second arm  13  is detected by the second angular velocity sensor  32  it is possible to suppress vibration more reliably. The actuation of the second driving source  402  which rotates the second arm  13  on the base end side from the third arm  14  is controlled, whereby it is possible to increase the effect of suppressing vibration of the robot  1 . 
     In the driving sources  401  to  406 , a first position sensor  411 , a second position sensor  412 , a third position sensor  413 , a fourth position sensor  414 , a fifth position sensor  415 , and a sixth position sensor  416  are respectively provided in the motors or the speed reducers. These position sensors are not particularly limited, and for example, an encoder, a rotary encoder, a resolver, a potentiometer, or the like may be used. The rotation angles of the shaft portions of the motors or the speed reducers of the driving sources  401  to  406  are detected by the position sensors  411  to  416 . The motors of the driving sources  401  to  406  are not particularly limited, and for example, a servomotor, such as an AC servomotor or a DC servomotor, is preferably used. The respective cables may be inserted into the robot  1 . 
     As shown in  FIG. 4 , the robot  1  is electrically connected to the robot control device  20 . That is, the driving sources  401  to  406 , the position sensors  411  to  416 , and the angular velocity sensors  31  and  32  are electrically connected to the robot control device  20 . 
     The robot control device  20  can actuate the arms  12  to  15  and the wrist  16  separately, that is, can control the driving sources  401  to  406  through the motor drivers  301  to  306  separately. In this case, the robot control device  20  performs detection by the position sensors  411  to  416 , the first angular velocity sensor  31 , and the second angular velocity sensor  32 , and controls the driving of the driving sources  401  to  406 , for example, the angular velocity, the rotation angle, or the like on the basis of the detection results. A control program is stored in a recording medium embedded in the robot control device  20  in advance. 
     As shown in  FIGS. 1 and 2 , if the robot  1  is a vertical articulated robot, the base  11  is a portion which is located on the lowermost side of the vertical articulated robot and is fixed to the floor  101  of the installation space. A fixing method is not particularly limited, and for example, in this embodiment shown in  FIGS. 1 and 2 , a fixing method by a plurality of bolts  111  is used. A fixing location of the base  11  in the installation space may be a wall or a ceiling of the installation space, instead of the floor. 
     The base  11  has a hollow base body (housing)  112 . The base body  112  can be divided into a cylindrical portion  113  having a cylindrical shape, and a boxlike portion  114  having a boxlike shape which is formed integrally in the outer circumferential portion of the cylindrical portion  113 . In the base body  112 , for example, the motor  401 M or the motor drivers  301  to  306  are stored. 
     Each of the arms  12  to  15  has a hollow arm body (housing)  2 , a driving mechanism  3 , and a sealing unit  4 . Hereinafter, for convenience of description, the arm body  2 , the driving mechanism  3 , and the sealing unit  4  of the first arm  12  are respectively referred to as “arm body  2   a ”, “driving mechanism  3   a ”, and “sealing unit  4   a ”, the arm body  2 , the driving mechanism  3 , and the sealing unit  4  of the second arm  13  are respectively referred to as “arm body  2   b ”, “driving mechanism  3   b ”, and “sealing unit  4   b ”, the arm body  2 , the driving mechanism  3 , and the sealing unit  4  of the third arm  14  are respectively referred to as “arm body  2   c ”, “driving mechanism  3   c ”, and “sealing unit  4   c ”, and the arm body  2 , the driving mechanism  3 , and the sealing unit  4  of the fourth arm  15  are respectively referred to as “arm body  2   d ”, “driving mechanism  3   d ”, and “sealing unit  4   d”.    
     Each of the joints  171  to  176  has a rotation support mechanism (not shown). The rotation support mechanism is a mechanism which rotatably supports one of two arms connected together with respect to the other arm, a mechanism which rotatably supports one of the base  11  and the first arm  12  connected together with respect to the other, or a mechanism which rotatably supports one of the fourth arm  15  and the wrist  16  connected together with respect to the other. In an example of the fourth arm  15  and the wrist  16  connected together, the rotation support mechanism can rotate the wrist  16  with respect to the fourth arm  15 . Each rotation support mechanism has a speed reducer (not shown) which reduces the rotation speed of the corresponding motor at a predetermined reduction ratio, and transmits the driving force to the corresponding arm, a wrist body  161  of the wrist  16 , and a support ring  162 . As described above, in this embodiment, the speed reducer and the motor are referred to as a driving source. 
     The first arm  12  is connected to the upper end port ion (front end portion) of the base  11  in a posture inclined with respect to the horizontal direction. In the first arm  12 , the driving mechanism  3   a  has the motor  402 M and is stored in the arm body  2   a . The arm body  2   a  is sealed airtight by the sealing unit  4   a . The arm body  2   a  has a pair of tongue piece portions  241   a  and  241   b  on the front end side, and a root portion  251  on the base end side. The tongue piece portion  241   a  and the tongue piece portion  241   b  are separated from each other and opposite to each other. The tongue piece portions  241   a  and  241   b  are inclined with respect to the root portion  251 , and thus, the first arm  12  is inclined with respect to the horizontal direction. A base end portion of the second arm  13  is arranged between the tongue piece portion  241   a  and the tongue piece portion  241   b.    
     The installation position of the first angular velocity sensor  31  in the first arm  12  is not particularly limited, and in this embodiment, as shown in  FIG. 6 , the first angular velocity sensor  31 , that is, the first angular velocity sensor unit  71  is provided in an end portion of the root portion  251  of the arm body  2   a  of the first arm  12  on an opposite side to an internal cable  85 . The cable  85  is a cable which supplies power to the motors  401 M to  406 M of the robot  1 . Accordingly, it is possible to prevent the first angular velocity sensor  31  from being affected by noise from the cable  85 , and to prevent a below-described circuit unit  713 , a wiring, and the first angular velocity sensor  31  of the first angular velocity sensor unit  71  from being short-circuited by the cable  85 . 
     Here, for the driving mechanism  3  and the speed reducer, representatively, the driving mechanism  3  which is provided in the arm body  2   a  of the first arm  12  and rotates the second arm  13  will be described. 
     As shown in  FIG. 5 , the driving mechanism  3  has a first pulley  91  which is connected to the shaft portion of the motor  402 M, a second pulley  92  which is arranged to be separated from the first pulley  91 , and a belt (timing belt)  93  which is stretched between the first pulley  91  and the second pulley  92 . The second pulley  92  and the shaft portion of the second arm  13  are connected together by the speed reducer  45 . 
     The speed reducer  45  is not particularly limited, and for example, a so-called “planetary gear-type” speed reducer having a plurality of gears, a harmonic drive (“Harmonic Drive” is Registered Trademark), or the like may be used. 
     A main cause for vibration of the arms  12  to  15  and the wrist  16  of the robot  1  is, for example, distortion or deflection of the speed reducer  45 , expansion and contraction of the belt  93 , deflection of the arms  12  to  15  and the wrist  16 , or the like. 
     The second arm  13  is connected to a front end portion of the first arm  12 . In the second arm  13 , the driving mechanism  3   b  has the motor  403 M and is stored in the arm body  2   b . The arm body  2   a  is sealed airtight by the sealing unit  4   b . The arm body  2   b  has a pair of tongue piece portions  242   a  and  242   b  on the front end side, and a root portion  252  on the base end side. The tongue piece portion  242   a  and the tongue piece portion  242   b  are separated from each other and opposite to each other. A base end portion of the third arm  14  is arranged between the tongue piece portion  242   a  and the tongue piece portion  242   b.    
     The third arm  14  is connected to a front end portion of the second arm  13 . In the third arm  14 , the driving mechanism  3   c  has the motor  404 M and is stored in the arm body  2   c . The arm body  2   c  is sealed airtight by the sealing unit  4   c . The arm body  2   c  is constituted by a member corresponding to the root portion  251  of the arm body  2   a  and the root portion  252  of the arm body  2   b.    
     The installation position of the second angular velocity sensor  32  in the third arm  14  is not particularly limited, and in this embodiment, as shown in  FIG. 7 , the second angular velocity sensor  32  that is, the second angular velocity sensor unit  72  is provided in an end portion of the arm body  2   c  of the third arm  14  on an opposite side to the internal cable  85 . Accordingly, it is possible to prevent the second angular velocity sensor  32  from being affected by noise from the cable  85 , and to prevent a circuit unit  723 , a wiring, and the second angular velocity sensor  32  of the second angular velocity sensor unit  72  from being short-circuited by the cable  85 . 
     The fourth arm  15  is connected to a front end portion of the third arm  14  in parallel with the center axis direction. In the fourth arm  15 , the driving mechanism  3   d  has the motors  405 M and  406 M and is stored in the arm body  2   d . The arm body  2   d  is sealed airtight by the sealing unit  4   d . The arm body  2   d  has a pair of tongue piece portions  244   a  and  244   b  on the front end side, and a root portion  254  on the base end side. The tongue piece portion  244   a  and the tongue piece portion  244   b  are separated from each other and opposite to each other. The support ring  162  of the wrist  16  is arranged between the tongue piece portion  244   a  and the tongue piece portion  244   b.    
     The wrist  16  is connected to a front end portion (an end portion on an opposite side to the base  11 ) of the fourth arm  15 . In the wrist  16 , for example, a manipulator (not shown) which holds precision equipment, such as a wristwatch, is detachably mounted as a functional unit (end effector) in the front end portion (the end portion on an opposite side to the fourth arm  15 ). The manipulator is not particularly limited, and for example, a configuration in which a plurality of finger portions are provided may be used. The robot  1  controls the operations of the arms  12  to  15 , the wrist  16 , and the like while holding the precision equipment with the manipulator, thereby conveying the precision equipment. 
     The wrist  16  has a cylindrical wrist body (sixth arm)  161 , and the ring-shaped support ring (fifth arm)  162  which is constituted separately from the wrist body  161  and is provided in the base end portion of the wrist body  161 . 
     A front end surface  163  of the wrist body  161  is a flat surface, and becomes a mounting surface on which the manipulator is mounted. The wrist body  161  is connected to the driving mechanism  3   d  of the fourth arm  15  through the joint  176 , and rotates around the sixth rotating axis O 6  by driving of the motor  406 M of the driving mechanism  3   d.    
     The support ring  162  is connected to the driving mechanism  3   d  of the fourth arm  15  through the joint  175 , and rotates around the fifth rotating axis O 5  along with the wrist body  161  by driving of the motor  405 M of the driving mechanism  3   d.    
     A constituent material of the arm body  2  is not particularly limited, and for example, various metal materials may be used and of these, aluminum or an aluminum alloy is particularly preferably used. If the arm body  2  is a casting which is molded using a mold, aluminum or an aluminum alloy is used as the constituent material of the arm body  2 , whereby it is possible to easily perform metallic molding. 
     A constituent material of each of the base body  112  of the base  11 , the wrist body  161  of the wrist  16 , and the support ring  162  is not particularly limited, and for example, the same material as the constituent material of the arm body  2  may be used. As a constituent material of the wrist body  161  of the wrist  16 , stainless steel is preferably used. 
     A constituent material of the sealing unit  4  is not particularly limited, and for example, various resin materials and various metal materials may be used. A resin material is used as the constituent material of the sealing unit  4 , whereby it is possible to achieve reduction in weight. 
     Next, the first angular velocity sensor unit  71  and the second angular velocity sensor unit  72  will be described. 
     As shown in  FIG. 8 , the first angular velocity sensor unit  71  has a first housing  711 , and a circuit board  712  having a wiring and the first angular velocity sensor  31  and a circuit unit  713  electrically connected onto the circuit board  712 , which are provided in the first housing  711 . In this embodiment, the first housing  711  is made of a sealing material, and the first angular velocity sensor  31 , the circuit unit  713 , and the circuit board  712  are collectively sealed by the sealing material. 
     Similarly, the second angular velocity sensor unit  72  has a second housing  721 , and a circuit board  722  having a wiring and the second angular velocity sensor  32  and a circuit unit  723  electrically connected onto the circuit board  722 , which are provided in the second housing  721 . In this embodiment, the second housing  721  is made of a seal ing material, and the second angular velocity sensor  32 , the circuit unit  723 , and the circuit board  722  are collectively sealed by the sealing material. 
     In this way, the first angular velocity sensor  31 , the circuit unit  713 , the second angular velocity sensor  32 , and the circuit unit  723  are packaged, thereby simplifying the configuration. Since the first angular velocity sensor unit  71  and the second angular velocity sensor unit  72  have the same configuration, hereinafter, the first angular velocity sensor unit  71  will be representatively described, and description of the second angular velocity sensor unit  72  will be omitted. 
     The first angular velocity sensor  31  has a gyro element  33  which includes one detection axis. The configuration of the gyro element  33  is not particularly limited, and for example, the following gyro element may be used. Hereinafter, as shown in  FIGS. 9, 10A, and 10B , the axes orthogonal to each other are defined as an X axis, a Y axis, and a Z axis. 
     As shown in  FIG. 9 , the gyro element  33  has a quartz substrate having a base portion  331 , a pair of detection vibrating arms  332   a  and  332   b  which extend from both sides of the base portion  331  in the Y-axis direction and in opposite directions, a pair of connecting arms  333   a  and  333   b  which extend from both sides of the base portion  331  in the X-axis direction and in opposite directions, a pair of driving vibrating arms  334   a  and  334   b  which extend from both sides of a front end portion of the connecting arm  333   a  in the Y-axis direction and in opposite directions, and a pair of driving vibrating arms  334   c  and  334   d  which extend from both sides of a front end portion of the connecting arm  333   b  in the Y-axis direction and in opposite directions, detection electrodes (not shown) which are provided in the respective detection vibrating arms  332   a  and  332   b , and driving electrodes (not shown) which are provided in the respective driving vibrating arms  334   a ,  334   b ,  334   c , and  334   d.    
     The gyro element  33  is actuated as follows. In  FIGS. 10A and 10B , the respective vibrating arms are represented by lines so as to easily express a vibration form. 
     First, as shown in  FIG. 10A , in a state where the angular velocity is not applied to the gyro element  33 , a voltage is applied to the driving electrodes to cause bending vibration of the respective driving vibrating arms  334   a ,  334   b ,  334   c , and  334   d  in a direction indicated by arrow E. In the bending vibration, a vibration mode indicated by a solid line and a vibration mode indicated by a two-dot-chain line are repeated at a predetermined frequency. At this time, the driving vibrating arms  334   a  and  334   b  and the driving vibrating arms  334   c  and  334   d  vibrate line-symmetrically with respect to the Y axis passing through the center of gravity G. 
     As shown in  FIG. 10B , in a state where the vibration is performed, if an angular velocity ω around the Z axis (detection axis) is applied to the gyro element  33 , a Coriolis force in a direction of arrow B acts on the driving vibrating arms  334   a ,  334   b ,  334   c , and  334   d  and the connecting arms  333   a  and  333   b , and renewed vibration is excited in these arms. Simultaneously, vibration in a direction of arrow C in response to vibration indicated by arrow B is excited in the detection vibrating arms  332   a  and  332   b . A signal (voltage) according to strain of the detection vibrating arms  332   a  and  332   b  caused by vibration of the detection vibrating arms  332   a  and  332   b  is output from the detection electrodes. 
     In the above, the gyro element  33  has been simply described. 
     The circuit unit  713  has an AD conversion unit which performs AD conversion on the signal output from the first angular velocity sensor  31 , that is, converts an analog signal to a digital signal, and a transmitting unit which transmits the converted signal to the robot control device  20 . 
     The appearance of the first housing  711  is a cube. The detection axis of the first angular velocity sensor  31  matches (is aligned with) the normal to the largest surface of the rectangular parallelepiped of the first housing  711 . With this, it is possible to recognize the directions of the detection axis of the first angular velocity sensor  31  and the detection axis of the second angular velocity sensor  32  easily and reliably, and to allow the first angular velocity sensor  31  and the second angular velocity sensor  32  to take an appropriate posture easily. In particular, as described above, since the gyro element  33  has a flat shape, and the normal to the plate surface is defined as the detection axis, it becomes easy to allow the detection axis of the first angular velocity sensor  31  to match (to be aligned with) the normal to the largest surface of the rectangular parallelepiped of the first housing  711 . 
     The first angular velocity sensor unit  71  is provided such that a detection axis  31   a  of the first angular velocity sensor  31  is inclined with respect to the first rotating axis O 1  at a predetermined angle (first angle) θ 1 . It should suffice that the angle θ 1  is equal to or greater than 0° and smaller than 90° (0°≦θ 1 &lt;90 °). If θ 1 =0°, the detection axis  31   a  of the first angular velocity sensor  31  matches (is parallel to) the first rotating axis O 1 . For this reason, the angular velocity detected by the first angular velocity sensor  31  substantially matches the angular velocity around the first rotating axis O 1  of the first arm  12 . Accordingly, it is possible to detect the angular velocity around the first rotating axis O 1  accurately without substantially correcting the angular velocity detected by the first angular velocity sensor  31 . 
     If 0°&lt;θ 1 &lt;90°, the detection axis  31   a  of the first angular velocity sensor  31  is inclined with respect to the first rotating axis O 1 . For this reason, the angular velocity detected by the first angular velocity sensor  31  is deviated from the angular velocity around the first rotating axis O 1  of the first arm  12 . However, if the angle θ 1  is set to a predetermined angle in advance, it is possible to detect the angular velocity around the first rotating axis O 1  of the first arm  12  accurately by correcting the angular velocity detected by the first angular velocity sensor  31  on the basis of the angle θ 1 . The correction at this time is a simple computation, and complicated and enormous computation is not required. For this reason, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot  1 . 
     For example, as shown in  FIG. 11A , a first axis J1 parallel to (or matching) the first rotating axis O 1 , a second axis (a axis) J2 orthogonal to the first axis J1, and a third axis (b axis) J3 orthogonal to both the first axis J1 and the second axis J2 are set, and when the angle around the second axis J2 of the detection axis  31   a  is α 1 , and the angle around the third axis J3 of the detection axis  31   a  is β 1 , and the angular velocity which is detected by the first angular velocity sensor  31  is ω 1 , ω 1  cos α 1  cos β 1  is set as the angular velocity around the first rotating axis O 1  of the first arm  12 . In order to secure high correction precision, it is preferable that θ 1  is as small as possible, and specifically, satisfies the range of 0°&lt;θ 1 ≦15°. When this range is satisfied, it is possible to detect the angular velocity around the first rotating axis O 1  of the first arm  12  with higher precision. However, the correction method is not limited to the above-described method. 
     In recent years, with the advancement of reduction in size and weight of the robot  1 , there is a case where the first angular velocity sensor  31  cannot be arranged at θ 1 =0° depending on the internal space of the first arm  12 . In this case, the first angular velocity sensor  31  is arranged in the first arm  12  such that θ 1  becomes a desired angle, whereby it is possible to detect the angular velocity around the first rotating axis O 1  of the first arm  12  with high precision. 
     The second angular velocity sensor unit  72  is provided such that a detection axis  32   a  of the second angular velocity sensor  32  is inclined with respect to the second rotating axis O 2  at a predetermined angle (second angle) θ 2 . It should suffice that the angle θ 2  is equal to or greater than 0° and smaller than 90° (0°≦θ 2 &lt;90°). If θ 2 =0°, the detection axis  32   a  of the second angular velocity sensor  32  matches (is parallel to) the second rotating axis O 2 . For this reason, the angular velocity detected by the second angular velocity sensor  32  substantially matches the angular velocity around the second rotating axis O 2  of the third arm  14 . Accordingly, it is possible to detect the angular velocity around the second rotating axis O 2  of the third arm  14  accurately without substantially correcting the angular velocity detected by the second angular velocity sensor  32 . 
     If 0°&lt;θ 2 &lt;90°, the detection axis  32   a  of the second angular velocity sensor  32  is inclined with respect to the second rotating axis O 2 . For this reason, the angular velocity detected by the second angular velocity sensor  32  is deviated from the angular velocity around the second rotating axis O 2  of the third arm  14 . However, if the angle θ 2  is set to a predetermined angle in advance, it is possible to detect the angular velocity around the second rotating axis O 2  of the third arm  14  accurately by correcting the angular velocity detected by the second angular velocity sensor  32  on the basis of the angle θ 2 . The correction at this time is a simple computation, and complicated and enormous computation is not required. For this reason, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot  1 . 
     For example, as shown in  FIG. 11B , a first axis J1′ parallel to (or matching) the second rotating axis O 2 , a second axis (c axis) J2′ orthogonal to the first axis J1 ‘, and a third axis (d axis) J3’ orthogonal to both the first axis J1′ and the second axis J2′ are set, and when the angle around the second axis J2′ of the detection axis  32   a  is α 2 , the angle around the third axis J3′ of the detection axis  32   a  is β 2 , and the angular velocity which is detected by the second angular velocity sensor  32  is ω 2 , ω 2  cos α 2  cos β 2  is set as the angular velocity around the second rotating axis O 2  of the third arm  14 . In order to secure high correction precision, it is preferable that θ 2  is as small as possible, and specifically, satisfies the range of 0°&lt;θ 2 ≦15°. When this range is satisfied, it is possible to detect the angular velocity around the second rotating axis O 2  of the third arm  14  with higher precision. However, the correction method is not limited to the above-described method. 
     In recent years, with the advancement of reduction in size and weight of the robot  1 , there is a case where the second angular velocity sensor  32  cannot be arranged at θ 2 =0° depending on the internal space of the third arm  14 . In this case, the second angular velocity sensor  32  is arranged in the third arm  14  such that θ 2  becomes a desired angle, whereby it is possible to detect the angular velocity around the second rotating axis O 2  of the third arm  14  with high precision. 
     As shown in  FIG. 6 or 8 , the first housing  711  has attachment portions  7111  to be attached to the first arm  12  in four corner portions. In each attachment portion  7111 , a hole  7112  into which a screw (fixing member)  81  is inserted is formed. 
     The first arm  12  has three arm-side attachment portions  121  which are formed integrally with the arm body  2   a  and to which the first angular velocity sensor unit  71  (first housing  711 ) is attached. Each arm-side attachment portion  121  is constituted by a fulcrum which is formed to protrude toward the arm body  2   a . The respective arm-side attachment portions  121  are arranged at positions corresponding to the attachment portions  7111  of the first housing  711 . In the front end portion of each arm-side attachment portion  121 , a threaded bore  122  into which the screw  81  is threaded is formed. 
     The term “integrally” in the arm-side attachment portions  121  formed integrally with the arm body  2   a  refers to a case where the arm body  2   a  and the arm-side attachment portions  121  are formed simultaneously by, for example, die-casting or the like, instead of forming members separately and bonding the members. The same applies to the term “integrally” in a below-described arm-side attachment portion  131  formed integrally with the arm body  2   b.    
     When attaching (providing) the first angular velocity sensor unit  71  to the first arm  12 , three screws  81  are inserted into the holes  7112  of the first housing  711  and threaded into the threaded bores  122  in the front end portions of the arm-side attachment portions  121  of the first arm  12 . With this, the three attachment portions  7111  of the first housing  711  are fixed to the arm-side attachment portions  121  of the first arm  12  by the screws  81 . That is, the first angular velocity sensor unit  71  is attached to the arm-side attachment portions  121  of the first arm  12 . In this case, there is nothing between the arm-side attachment portions  121  and the first angular velocity sensor unit  71 , that is, the first angular velocity sensor unit  71  is directly attached to the arm-side attachment portions  121 . With this, it is possible to attach the first angular velocity sensor unit  71  to the first arm  12  reliably, and to allow the first angular velocity sensor unit  71  to rotate integrally with the first arm  12  reliably. 
     The term “directly” when the first angular velocity sensor unit  71  is directly attached to the arm-side attachment portions  121  refers to a case excluding a case where the first angular velocity sensor unit  71  is attached to an intermediate, such as a separate substrate, and the intermediate is attached to the arm-side attachment portions  121 . That is, the term “directly” refers to a case where there is nothing, excluding an adhesive or the like, between the arm-side attachment portions  121  and the first angular velocity sensor unit  71 . The same applies to the term “directly” when the below-described second angular velocity sensor unit  72  is directly attached to an arm-side attachment portion  131 . 
     The screws  81  are conductive and are formed of, for example, various metal materials. If the screws  81  are inserted into the holes  7112  of the first housing  711  and are threaded into the threaded bores  122  in the front end portions of the arm-side attachment portions  121 , the screws  81  are electrically connected to the wiring of the circuit board  712  electrically connected to a ground terminal of the circuit unit  713 , and the front end portions of the screws  81  are electrically connected to the arm-side attachment portions  121 . With this, the ground terminal of the circuit unit  713  is electrically connected to the arm body  2   a  of the first arm  12  through the wiring and the screws  81  and grounded. Accordingly, it is possible to reduce the number of components for grounding and to simplify the configuration. 
     As shown in  FIGS. 7 and 8 , the second housing  721  has attachment portions  7211  to be attached to the third arm  14  in four corner portions. In each attachment portion  7211 , a hole  7212  into which the screw  81  is inserted is formed. 
     As shown in  FIG. 7 , the third arm  14  has an arm-side attachment portion  141  which is formed integrally with the arm body  2   c  and to which the second angular velocity sensor unit  72  (second housing  721 ) is attached. The arm-side attachment portion  141  has a shape corresponding to the second housing  721 . That is, the arm-side attachment portion  141  has a plate shape, and the shape in plan view is a quadrangular shape, in this embodiment, a rectangular shape. In each corner portion of the arm-side attachment portion  141 , a threaded bore into which the screw  81  is threaded is formed. 
     When attaching the second angular velocity sensor unit  72  to the third arm  14 , the four screws  81  are inserted into the holes  7212  of the second housing  721  and threaded into the threaded bores in the front end portions of the arm-side attachment portion  141  of the third arm  14 . With this, the four attachment portions  7211  of the second housing  721  are fixed to the arm-side attachment portion  141  of the third arm  14  by the screws  81 . That is, the second angular velocity sensor unit  72  is attached to the arm-side attachment portion  141  of the third arm  14 . In this case, there is nothing between the arm-side attachment portion  141  and the second angular velocity sensor unit  72 , that is, the second angular velocity sensor unit  72  is directly attached to the arm-side attachment portions  141 . Accordingly, it is possible to attach the second angular velocity sensor unit  72  to the third arm  14  reliably, and to allow the second angular velocity sensor unit  72  to rotate integrally with the third arm  14  reliably. 
     If the screws  81  are inserted into the holes  7212  of the second housing  721  and threaded into the threaded bores of the arm-side attachment portion  141 , the screws  81  are electrically connected to a wiring of the circuit board  722  electrically connected to a ground terminal of the circuit unit  723 , and the front end portions of the screws  81  are electrically connected to the arm-side attachment portion  141 . With this, the ground terminal of the circuit unit  723  is electrically connected to the arm body  2   c  of the third arm  14  through the wiring and the screws  81  and grounded. Accordingly, it is possible to reduce the number of components for grounding and to simplify the configuration. 
     Next, the configuration of the robot control device  20  will be described referring to  FIGS. 4 and 12 to 16 . 
     The robot control device  20  has a receiving unit which receives a first signal output from the first angular velocity sensor  31 , a second signal output from the second angular velocity sensor  32 , and respective signals output from the position sensors  411  to  416 , a calculation unit which obtains a vibrational component of the angular velocity of the first arm  12  and a vibrational component of the angular velocity of the third arm  14  on the basis of the first signal and the second signal received by the receiving unit, and a control unit which controls the actuation of the robot  1  on the basis of the vibrational component of the angular velocity of the first arm  12  and the vibrational component of the angular velocity of the third arm  14  obtained by the calculation unit. 
     Specifically, as shown in  FIGS. 4 and 12 to 16 , the robot control device  20  has the receiving unit, a first driving source control unit  201  which controls the actuation of the first driving source  401 , a second driving source control unit  202  which controls the actuation of the second driving source  402 , a third driving source control unit  203  which controls the actuation of the third driving source  403 , a fourth driving source control unit  204  which controls the actuation of the fourth driving source  404 , a fifth driving source control unit  205  which controls the actuation of the fifth driving source  405 , and a sixth driving source control unit  206  which controls the actuation of the sixth driving source  406 . 
     The calculation unit has a below-described angular velocity calculation unit  561  and a subtracter  571  of the first driving source control unit  201 , a below-described angular velocity calculation unit  562  and an adder-subtracter  622  of the second driving source control unit  202 , and a below-described angular velocity calculation unit  563  of the third driving source control unit  203 . 
     As shown in  FIG. 12 , the first driving source control unit  201  has a subtracter  511 , a position control unit  521 , a subtracter  531 , an angular velocity control unit  541 , a rotation angle calculation unit  551 , an angular velocity calculation unit  561 , a subtracter  571 , a conversion unit  581 , a correction value calculation unit  591 , and an adder  601 . 
     As shown in  FIG. 13 , the second driving source control unit  202  has a subtracter  512 , a position control unit  522 , a subtracter  532 , an angular velocity control unit  542 , a rotation angle calculation unit  552 , an angular velocity calculation unit  562 , an adder-subtracter  622 , a conversion unit  582 , a correction value calculation unit  592 , and an adder  602 . 
     As shown in  FIG. 13 , the third driving source control unit  203  has a subtracter  513 , a position control unit  523 , a subtracter  533 , an angular velocity control unit  543 , a rotation angle calculation unit  553 , and an angular velocity calculation unit  563 . 
     As shown in  FIG. 14 , the fourth driving source control unit  204  has a subtracter  514 , a position control unit  524 , a subtracter  534 , an angular velocity control unit  544 , a rotation angle calculation unit  554 , and an angular velocity calculation unit  564 . 
     As shown in  FIG. 15 , the fifth driving source control unit  205  has a subtracter  515 , a position control unit  525 , a subtracter  535 , an angular velocity control unit  545 , a rotation angle calculation unit  555 , and an angular velocity calculation unit  565 . 
     As shown in  FIG. 16 , the sixth driving source control unit  206  has a subtracter  516 , a position control unit  526 , a subtracter  536 , an angular velocity control unit  546 , a rotation angle calculation unit  556 , and an angular velocity calculation unit  566 . 
     Here, the robot control device  20  calculates a target position of the wrist  16  on the basis of the content of processing performed by the robot  1 , and produces a track for moving the wrist  16  to the target position. The robot control device  20  measures the rotation angle of each of the driving sources  401  to  406  at every predetermined control period such that the wrist  16  moves along the produced track, and outputs values calculated on the basis of the measurement results to the driving source control units  201  to  206  as a position command Pc of each of the driving sources  401  to  406  (see  FIGS. 12 to 16 ). In the above and following description, the description “the values are input and output” or the like means that “signals corresponding to the values are input and output”. 
     As shown in  FIG. 12 , in addition to the position command Pc of the first driving source  401 , the detection signals from the first position sensor  411  and the first angular velocity sensor  31  (correction unit  611 ) are input to the first driving source control unit  201 . The first driving source control unit  201  drives the first driving source  401  by feedback control using the respective detection signals such that the rotation angle (position feedback value Pfb) of the first driving source calculated from the detection signal of the first position sensor  411  becomes the position command Pc and a below-described angular velocity feedback value ωfb becomes a below-described angular velocity command ωc. 
     That is, the position command Pc and a below-described position feedback value Pfb from the rotation angle calculation unit  551  are input to the subtracter  511  of the first driving source control unit  201 . In the rotation angle calculation unit  551 , the number of pulses input from the first position sensor  411  is counted, and the rotation angle of the first driving source  401  according to the count value is output to the subtracter  511  as the position feedback value Pfb. The subtracter  511  outputs the deviation (the value obtained by subtracting the position feedback value Pfb from a target value of the rotation angle of the first driving source  401 ) between the position command Pc and the position feedback value Pfb to the position control unit  521 . 
     The position control unit  521  performs predetermined calculation processing using the deviation input from the subtracter  511 , and a proportional gain or the like as a preset coefficient, and calculates a target value of the angular velocity of the first driving source  401  according to the deviation. The position control unit  521  outputs a signal representing the target value (command value) of the angular velocity of the first driving source  401  to the subtracter  531  as the angular velocity command ωc. Here, in this embodiment, although proportional control (P control) is performed as feedback control, the invention is not limited thereto. 
     The angular velocity command ωc and a below-described angular velocity feedback value ωfb are input to the subtracter  531 . The subtracter  531  outputs the deviation (the value obtained by subtracting the angular velocity feedback value ωfb from the target value of the angular velocity of the first driving source  401 ) between the angular velocity command ωc and the angular velocity feedback value ωfb to the angular velocity control unit  541 . 
     The angular velocity control unit  541  performs predetermined calculation processing including integration using the deviation input from the subtracter  531 , and a proportional gain, an integral gain, and the like as preset coefficients, produces a driving signal (driving current) of the first driving source  401  according to the deviation, and supplies the driving signal to the motor  401 M through the motor driver  301 . Here, in this embodiment, although PI control is performed as feedback control, the invention is not limited thereto. 
     In this way, the feedback control is performed such that the position feedback value Pfb becomes equal to the position command Pc as much as possible and the angular velocity feedback value ωfb becomes equal to the angular velocity command ωc as much as possible, and the driving current of the first driving source  401  is controlled. 
     Next, the angular velocity feedback value ωfb in the first driving source control unit  201  will be described. 
     In the angular velocity calculation unit  561 , an angular velocity ωm 1  of the first driving source  401  is calculated on the basis of the frequency of a pulse signal input from the first position sensor  411 , and the angular velocity ωm1 is output to the adder  601 . 
     In the angular velocity calculation unit  561 , an angular velocity ωA 1  m around the first rotating axis O 1  of the first arm  12  is calculated on the basis of the frequency of the pulse signal input from the first position sensor  411 , and the angular velocity ωA 1  m is output to the subtracter  571 . The angular velocity ωA 1  m is a value obtained by dividing the angular velocity ωm 1  by a reduction ratio between the motor  401 M of the first driving source  401  and the first arm  12 , that is, in the joint  171 . 
     An angular velocity ωA 1 ′ corresponding to the rotation around the first rotating axis O 1  of the first arm  12  is detected by the first angular velocity sensor  31 , and the detected angular velocity ωA 1 ′ is output to a correction unit  611 . For example, the correction unit  611  multiplies the angular velocity ωA 1 ′ input from the first angular velocity sensor  31  by cos α 1  cos β 1 . ωA 1  ′ cos α 1  cos β 1  is output to the subtracter  571  as an angular velocity ωA1 around the first rotating axis O 1  of the first arm  12 . However, if θ 1 =0°, since ωA 1 ′=ωA 1 , correction by the correction unit  611  is not required, and the correction unit  611  may be omitted. 
     The angular velocity ωA1 and the angular velocity ωA1m are input to the subtracter  571 , and the subtracter  571  outputs a value ωA 1  s (=ωA 1 −ωA 1  m) obtained by subtracting the angular velocity ωA1m from the angular velocity ωA 1  to the conversion unit  581 . The value ωA 1  s corresponds to a vibrational component (vibrational angular velocity) of the angular velocity around the first rotating axis O 1  of the first arm  12 . Hereinafter, ωA 1  s is referred to as a vibrational angular velocity. In this embodiment, feedback control is performed to return a below-described gain Ka multiple of the vibrational angular velocity ωA 1  s (in detail, an angular velocity ωm 1  s in the motor  401 M which is a value produced on the basis of the vibrational angular velocity ωA 1  s) to the input side of the first driving source  401 . Specifically, the feedback control is performed on the first driving source  401  such that the vibrational angular velocity ωA 1  s becomes 0 as much as possible. Accordingly, it is possible to suppress vibration of the robot  1 . In the feedback control, the angular velocity of the first driving source  401  is controlled. 
     The conversion unit  581  converts the vibrational angular velocity ωA 1  s to the angular velocity ωm 1  s in the first driving source  401 , and outputs the angular velocity ωm 1  s to the correction value calculation unit  591 . The conversion can be performed by multiplying the vibrational angular velocity ωA 1  s by a reduction ratio between the motor  401 M of the first driving source  401  and the first arm  12 , that is, in the joint  171 . 
     The correction value calculation unit  591  multiplies the angular velocity ωm 1  s by the gain (feedback gain) Ka as a preset coefficient, obtains a correction value Ka·ωm 1  s, and outputs the correction value Ka·ωm 1  s to the adder  601 . 
     The angular velocity ωm 1  and the correction value Ka·ωm1s are input to the adder  601 . The adder  601  outputs the sum of the angular velocity ωm 1  and the correction value Ka·ωm1s to the subtracter  531  as the angular velocity feedback value ωfb. A subsequent operation is as described above. 
     As shown in  FIG. 13 , in addition to the position command Pc of the second driving source  402 , the detection signals from the second position sensor  412  and the second angular velocity sensor  32  (correction unit  612 ) are input to the second driving source control unit  202 . The angular velocity ωA3m around the third rotating axis O 3  of the third arm  14  from the third driving source control unit  203  is input to the second driving source control unit  202 . The second driving source control unit  202  drives the second driving source  402  by feedback control using the respective detection signals such that the rotation angle (position feedback value Pfb) of the second driving source calculated from the detection signal of the second position sensor  412  becomes the position command Pc and a below-described angular velocity feedback value ωfb becomes a below-described angular velocity command ωc. 
     That is, the position command Pc and a below-described position feedback value Pfb from the rotation angle calculation unit  552  are input to the subtracter  512  of the second driving source control unit  202 . In the rotation angle calculation unit  552 , the number of pulses input from the second position sensor  412  is counted, and the rotation angle of the second driving source  402  according to the count value is output to the subtracter  512  as the position feedback value Pfb. The subtracter  512  outputs the deviation (the value obtained by subtracting the position feedback value Pfb from a target value of the rotation angle of the second driving source  402 ) between the position command Pc and the position feedback value Pfb to the position control unit  522 . 
     The position control unit  522  performs predetermined calculation processing using the deviation input from the subtracter  512 , and a proportional gain or the like as a preset coefficient, and calculates the target value of the angular velocity of the second driving source  402  according to the deviation. The position control unit  522  outputs a signal representing the target value (command value) of the angular velocity of the second driving source  402  to the subtracter  532  as the angular velocity command ωc. Here, in this embodiment, although proportional control (P control) is performed as feedback control, the invention is not limited thereto. 
     The angular velocity command ωc and a below-described angular velocity feedback value ωfb are input to the subtracter  532 . The subtracter  532  outputs the deviation (the value obtained by subtracting the angular velocity feedback value ωfb from the target value of the angular velocity of the second driving source  402 ) between the angular velocity command ωc and the angular velocity feedback value ωfb to the angular velocity control unit  542 . 
     The angular velocity control unit  542  performs predetermined calculation processing including integration using the deviation input from the subtracter  532 , and a proportional gain, an integral gain, and the like as preset coefficients, produces a driving signal (driving current) of the second driving source  402  according to the deviation, and supplies the driving signal to the motor  402 M through the motor driver  302 . Here, in this embodiment, although PI control is performed as feedback control, the invention is not limited thereto. 
     In this way, the feedback control is performed such that the position feedback value Pfb becomes equal to the position command Pc as much as possible and the angular velocity feedback value ωfb becomes equal to the angular velocity command ωc as much as possible, and the driving current of the second driving source  402  is controlled. Since the second rotating axis O 2  is orthogonal to the first rotating axis O 1 , it is possible to control the actuation of the second driving source  402  separately from the first driving source  401  without being affected by operation or vibration of the first arm  12 . 
     Next, the angular velocity feedback value ωfb in the second driving source control unit  202  will be described. 
     In the angular velocity calculation unit  562 , an angular velocity ωm 2  of the second driving source  402  is calculated on the basis of the frequency of a pulse signal input from the second position sensor  412 , and the angular velocity ωm 2  is output to the adder  602 . 
     In the angular velocity calculation unit  562 , an angular velocity ωA 2  m around the second rotating axis O 2  of the second arm  13  is calculated on the basis of the frequency of the pulse signal input from the second position sensor  412 , and the angular velocity ωA 2  m is output to the adder-subtracter  622 . The angular velocity ωA 2  m is a value obtained by dividing the angular velocity ωm 2  by a reduction ratio between the motor  402 M of the second driving source  402  and the second arm  13 , that is, in the joint  172 . 
     In the angular velocity calculation unit  563  of the third driving source control unit  203 , the angular velocity ωA 3  m around the third rotating axis O 3  of the third arm  14  is calculated on the basis of the frequency of a pulse signal input from the third position sensor  413 , and the angular velocity ωA 3  m is output to the adder-subtracter  622 . The angular velocity ωA 3  m is a value obtained by dividing the angular velocity ωm 3  by a reduction ratio between the motor  403 M of the third driving source  403  and the third arm  14 , that is, in the joint  173 . 
     An angular velocity ωA 3 ′ corresponding to the rotation around the second rotating axis O 2  of the third arm  14  is detected by the second angular velocity sensor  32 , and the detected angular velocity ωA 3 ′ is output to a correction unit  612 . For example, the correction unit  612  multiplies the angular velocity ωA 3 ′ input from the second angular velocity sensor  32  by cos α 2  cos β 2 . ωA 3 ′ cos α 2  cos β 2  is output to the adder-subtracter  622  as an angular velocity ωA 3  around the second rotating axis O 2  of the third arm  14 . However, if θ 2 =0°, since ωA 3 ′=ωA 3 , correction by the correction unit  612  is not required, and the correction unit  612  may be omitted. 
     Since the second rotating axis O 2  and the third rotating axis O 3  are orthogonal to the first rotating axis O 1 , it is possible to obtain the angular velocity around the second rotating axis O 2  of the third arm  14  easily and reliably without being affected by operation or vibration of the first arm  12 . 
     The angular velocity ωA 3 , the angular velocity ωA 2  m, and the angular velocity ωA 3  m are input to the adder-subtracter  622 , and the adder-subtracter  622  outputs a value ωA 2  s (=ωA 3  −ωA 2  m−ωA 3  m) obtained by subtracting the angular velocity ωA 2  m and the angular velocity ωA 3  m from the angular velocity ωA 3  to the conversion unit  582 . The value ωA 2  s corresponds to the vibrational component (vibrational angular velocity) of the total angular velocity around the second rotating axis O 2  of the second arm  13  and the third arm  14 . Hereinafter, ωA 2  s is referred to as a vibrational angular velocity. In this embodiment, feedback control is performed to return a below-described gain Ka multiple of the vibrational angular velocity ωA 2  s (in detail, an angular velocity ωm 2  s in the motor  402 M which is a value produced on the basis of the vibrational angular velocity ωA 2  s) to the input side of the second driving source  402 . Specifically, the feedback control is performed on the second driving source  402  such that the vibrational angular velocity ωA 2  s becomes close to 0 as much as possible. Accordingly, it is possible to suppress vibration of the robot  1 . In the feedback control, the angular velocity of the second driving source  402  is controlled. 
     The conversion unit  582  converts the vibrational angular velocity ωA 2  s to the angular velocity ωm 2  s in the second driving source  402 , and outputs the angular velocity ωm 2  s to the correction value calculation unit  592 . The conversion can be performed by multiplying the vibrational angular velocity ωA 2  s by a reduction ratio between the motor  402 M of the second driving source  402  and the second arm  13 , that is, in the joint  172 . 
     The correction value calculation unit  592  multiplies the angular velocity ωm 2  s by the gain (feedback gain) Ka as a preset coefficient, obtains a correction value Ka·ωm2s, and outputs the correction value Ka·ωm 2  s to the adder  602 . The gain Ka in the second driving source control unit  202  and the gain Ka in the first driving source control unit  201  may be the same or different from each other. 
     The angular velocity ωm 2  and the correction value Ka·ωm 2  s are input to the adder  602 . The adder  602  outputs the sum of the angular velocity ωm 2  and the correction value Ka·ωm 2  s to the subtracter  532  as the angular velocity feedback value ωfb. A subsequent operation is as described above. 
     As shown in  FIG. 13 , in addition to the position command Pc of the third driving source  403 , the detection signal from the third position sensor  413  is input to the third driving source control unit  203 . The third driving source control unit  203  drives the third driving source  403  by feedback control using the respective detection signals such that the rotation angle (position feedback value Pfb) of the third driving source  403  calculated from the detection signal of the third position sensor  413  becomes the position command Pc and a below-described angular velocity feedback value ωfb becomes a below-described angular velocity command ωc. 
     That is, the position command Pc and a below-described position feedback value Pfb from the rotation angle calculation unit  553  are input to the subtracter  513  of the third driving source control unit  203 . In the rotation angle calculation unit  553 , the number of pulses input from the third position sensor  413  is counted, and the rotation angle of the third driving source  403  according to the count value is output to the subtracter  513  as the position feedback value Pfb. The subtracter  513  outputs the deviation (the value obtained by subtracting the position feedback value Pfb from a target value of the rotation angle of the third driving source  403 ) between the position command Pc and the position feedback value Pfb to the position control unit  523 . 
     The position control unit  523  performs predetermined calculation processing using the deviation input from the subtracter  513 , and a proportional gain or the like as a preset coefficient, and calculates a target value of the angular velocity of the third driving source  403  according to the deviation. The position control unit  523  outputs a signal representing the target value (command value) of the angular velocity of the third driving source  403  to the subtracter  533  as the angular velocity command ωc. Here, in this embodiment, although proportional control (P control) is performed as feedback control, the invention is not limited thereto. 
     In the angular velocity calculation unit  563 , the angular velocity of the third driving source  403  is calculated on the basis of the frequency of a pulse signal input from the third position sensor  413 , and the angular velocity is output to the subtracter  533  as the angular velocity feedback value ωfb. 
     The angular velocity command ωc and the angular velocity feedback value ωfb are input to the subtracter  533 . The subtracter  533  outputs the deviation (the value obtained by subtracting the angular velocity feedback value ωfb from the target value of the angular velocity of the third driving source  403 ) between the angular velocity command ωc and the angular velocity feedback value ωfb to the angular velocity control unit  543 . 
     The angular velocity control unit  543  performs predetermined calculation processing including integration using the deviation input from the subtracter  533 , and a proportional gain, an integral gain, and the like as preset coefficients, produces a driving signal (driving current) of the third driving source  403  according to the deviation, and supplies the driving signal to the motor  403 M through the motor driver  303 . Here, in this embodiment, although PI control is performed as feedback control, the invention is not limited thereto. 
     In this way, the feedback control is performed such that the position feedback value Pfb becomes equal to the position command Pc as much as possible and the angular velocity feedback value ωfb becomes equal to the angular velocity command ωc as much as possible, and the driving current of the third driving source  403  is controlled. 
     The driving source control units  204  to  206  are the same as the third driving source control unit  203 , and thus, description thereof will not be repeated. 
     As described above, in the robot  1  and the robot system  10 , the angular velocity of the first arm  12  can be detected by the first angular velocity sensor  31 , and since the third rotating axis O 3  is parallel to the second rotating axis O 2 , the angular velocity of the third arm  14  including the rotation amount of the second arm  13  can be detected by the second angular velocity sensor  32 . Then, it is possible to suppress vibration on the basis of these detection results. 
     Since the angular velocity of the third arm  14  including the rotation amount of the second arm  13  is detected by the second angular velocity sensor  32  instead of the angular velocity of the second arm  13 , it is possible to suppress vibration more reliably. It is also possible to reduce the number of angular velocity sensors, to reduce cost, and to simplify the configuration compared to a case where an angular velocity sensor is also provided in the second arm  13 . The actuation of the second driving source  402  which rotates the second arm  13  on the base end side from the third arm  14  is controlled, whereby it is possible to increase the effect of suppressing vibration of the robot  1 . 
     Second Embodiment 
       FIG. 17  is a perspective view showing a position adjustment member in a robot according to a second embodiment of the invention. 
     Hereinafter, the robot of the second embodiment will be described focusing on a difference from the above-described first embodiment, and description of the same matters will not be repeated. 
     The robot according to the second embodiment of the invention is the same as that in the above-described first embodiment, except that an angular velocity sensor unit is arranged in an arm through a position adjustment member. The same parts as those in the above-described first embodiment are represented by the same reference numerals. 
     As shown in  FIG. 17 , in the robot  1  of this embodiment, the first angular velocity sensor unit  71  is fixed to the first arm  12  through a posture adjustment member (first position adjustment member)  810 . The posture adjustment member  810  has a universal joint and is configured to adjust the posture of the first angular velocity sensor unit  71 . Specifically, the posture adjustment member  810  has a fixed portion  811  which is fixed to the first arm  12  (arm-side attachment portions  121 ), a movable portion  812  to which the first angular velocity sensor unit  71  is fixed, and a spider  813  which connects the fixed portion  811  and the movable portion  812 . The spider  813  has a cross shape in which rod-shaped portions  813   a  and  813   b  are orthogonal to each other, both ends of the rod-shaped portion  813   a  are connected to the fixed portion  811 , and both ends of the rod-shaped portion  813   b  are connected to the movable portion  812 . The posture adjustment member  810  further has a first fixing screw  814  which passes through the fixed portion  811  and is threaded into the rod-shaped portion  813   a , and a second fixing screw  815  which passes through the movable portion  812  and is threaded into the rod-shaped portion  813   b . If the first fixing screw  814  is unfastened, the spider  813  is rotatable around the axis of the rod-shaped portion  813   a  with respect to the fixed portion  811 , and if the first fixing screw  814  is fastened, the spider  813  is not rotatable with respect to the fixed portion  811 , and the posture of the spider  813  with respect to the fixed portion  811  is fixed and maintained. Similarly, if the second fixing screw  815  is unfastened, the movable portion  812  is rotatable around the axis of the rod-shaped portion  813   b  with respect to the spider  813 , and if the second fixing screw  815  is fastened, the movable portion  812  is not rotatable with respect to the spider  813 , and the posture of the movable portion  812  with respect to the spider  813  is fixed and maintained. With the posture adjustment member  810 , it is possible to freely adjust the inclination angle θ 1  (α 1 , β 1 ) of the detection axis  31   a  of the first angular velocity sensor  31  with respect to the first rotating axis O 1 . 
     In general, as the inclination angle θ 1  (α 1 , β 1 ) increases, the deviation between the angular velocity ωA 1  around the first rotating axis O 1  of the first arm  12  output from the correction unit  611  and the actual angular velocity around the first rotating axis O 1  of the first arm  12  tends to increase. Accordingly, it is preferable to suppress the inclination angle θ 1  (α 1 , β 1 ) to be as small as possible. However, there is a case where, if the inclination angle θ 1  (α 1 , β 1 ) is within a specific range, the deviation between the angular velocity ωA 1  around the first rotating axis O 1  of the first arm  12  output from the correction unit  611  and the actual angular velocity around the first rotating axis O 1  of the first arm  12  decreases, compared to a case where the inclination angle is out of the range, due to various factors depending on the configuration of the robot  1 . The posture adjustment member  810  is provided, whereby it is possible to match the detection axis  31   a  at the inclination angle θ 1  (α 1 , β 1 ) within the above-described range, and to detect the angular velocity around the first rotating axis O 1  of the first arm  12  more accurately. 
     As shown in  FIG. 17 , the second angular velocity sensor unit  72  is fixed to the third arm  14  (arm-side attachment portion  141 ) through a posture adjustment member (second position adjustment member)  820 . The posture adjustment member  820  has a universal joint and is configured to adjust the posture of the second angular velocity sensor unit  72 . Specifically, the posture adjustment member  820  has a fixed portion  821  which is fixed to the third arm  14 , a movable portion  822  to which the second angular velocity sensor unit  72  is fixed, and a spider  823  which connects the fixed portion  821  and the movable portion  822 . The spider  823  has a cross shape in which rod-shaped portions  823   a  and  823   b  are orthogonal to each other, both ends of the rod-shaped portion  823   a  are connected to the fixed portion  821 , and both ends of the rod-shaped portion  823   b  are connected to the movable portion  822 . The posture adjustment member  820  has a first fixing screw  824  which passes through the fixed portion  821  and is threaded into the rod-shaped portion  823   a , and a second fixing screw  825  which passes through the movable portion  822  and is threaded into the rod-shaped portion  823   b . If the first fixing screw  824  is unfastened, the spider  823  is rotatable around the axis of the rod-shaped portion  823   a  with respect to the fixed portion  821 , and if the first fixing screw  824  is fastened, the spider  823  is not rotatable with respect to the fixed portion  821 , and the posture of the spider  823  with respect to the fixed portion  821  is fixed and maintained. Similarly, if the second fixing screw  825  is unfastened, the movable portion  822  is rotatable around the axis of the rod-shaped portion  823   b  with respect to the spider  823 , and if the second fixing screw  825  is fastened, the movable portion  822  is not rotatable with respect to the spider  823 , and the posture of the movable portion  822  with respect to the spider  823  is fixed and maintained. With the posture adjustment member  820 , it is possible to freely adjust the inclination angle θ 2  (α 2 , β 2 ) of the detection axis  32   a  of the second angular velocity sensor  32  with respect to the second rotating axis O 2 . 
     In general, as the inclination angle θ 2  (α 2 , β 2 ) increases, the deviation between the angular velocity ωA 3  around the second rotating axis O 2  of the third arm  14  output from the correction unit  612  and the actual angular velocity around the second rotating axis O 2  of the third arm  14  tends to increase. Accordingly, it is preferable to suppress the inclination angle θ 2  (α 2 , β 2 ) to be as small as possible. However, there is a case where, if the inclination angle θ 2  (α 2 , β 2 ) is within a specific range, the deviation between the angular velocity ωA 3  around the second rotating axis O 2  of the third arm  14  output from the correction unit  612  and the actual angular velocity around the second rotating axis O 2  of the third arm  14  decreases, compared to a case where the inclination angle is out of the range, due to various factors depending on the configuration of the robot  1 . The posture adjustment member  820  is provided, whereby it is possible to match the detection axis  32   a  at the inclination angle θ 2  (α 2 , β 2 ) within the above-described range, and to detect the angular velocity around the second rotating axis O 2  of the third arm  14  more accurately. 
     It is preferable that the posture adjustment members  810  and  820  are made of a conductive material, such as metal. Accordingly, the ground terminals of the circuit units  713  and  723  can be electrically connected to the arm bodies  2   a  and  2   c  of the first and third arms  12  and  14  through the wirings, the screws  81 , and the posture adjustment members  810  and  820  and grounded. 
     The configuration of each of the posture adjustment members  810  and  820  is not particularly limited insofar as the posture of each of the first and second angular velocity sensor units  71  and  72  (the direction of each of the detection axes  31   a  and  32   a ) can be adjusted. 
     According to the second embodiment, the same effects as in the above-described first embodiment can be exhibited. 
     Third Embodiment 
       FIG. 18  is a perspective view showing a second arm of a robot according to a third embodiment of the invention.  FIG. 19  is a diagram showing the slope between a detection axis of an angular velocity sensor and a rotating axis of an arm.  FIGS. 20 and 21  are block diagrams of a part of the robot shown in  FIG. 18 , respectively. 
     Hereinafter, the robot of the third embodiment will be described focusing on a difference from the above-described first embodiment, and description of the same matters will not be repeated. 
     The robot according to the third embodiment of the invention is the same as that in the above-described first embodiment, except that the second angular velocity sensor unit is arranged in the second arm. The same parts as those in the above-described first embodiment are represented by the same reference numerals. 
     As shown in  FIG. 18 , in the robot  1  of this embodiment, the second angular velocity sensor  32  (second angular velocity sensor unit  72 ) is provided in the second arm  13 . The installation position of the second angular velocity sensor  32  in the second arm  13  is not particularly limited, and in this embodiment, as shown in  FIG. 18 , the second angular velocity sensor  32  is provided in an end portion of the arm body  2   b  of the second arm  13  on an opposite side to the internal cable  85 . In other words, the second angular velocity sensor  32  is arranged in the tongue piece portion  242   a  separated from the tongue piece portion  242   b , through which the cable  85  passes. Accordingly, it is possible to prevent the second angular velocity sensor  32  from being affected by noise from the cable  85 , and to prevent the circuit unit  723 , the wiring, and the second angular velocity sensor  32  of the second angular velocity sensor unit  72  from being short-circuited by the cable  85 . 
     It is preferable that the second angular velocity sensor  32  is located on the front end side of the second arm  13 . In other words, it is preferable that the second angular velocity sensor  32  (second angular velocity sensor unit  72 ) is arranged such that the distance from the third rotating axis O 3  is shorter than the distance from the second rotating axis O 2 . With this, the second angular velocity sensor  32  can be arranged at a position close to the third arm  14 . For this reason, as described below, the vibrational component of the third arm  14  transmitted to the second arm  13  can be detected by the second angular velocity sensor  32  more efficiently (before attenuation increases). Accordingly, it is possible to increase the effect of suppressing vibration of the robot  1 . 
     The speed reducer  45  is provided on the third rotating axis O 3  in the third arm  14 , and the third arm  14  is connected to the second arm  13  through the speed reducer  45 . If a rigid “planetary gear-type” speed reducer is used as the speed reducer  45 , the vibrational component (the vibrational component of the angular velocity around the third rotating axis O 3 , and the same applies to the below) of the third arm  14  is easily transmitted to the second arm  13  through the speed reducer  45 . For this reason, the angular velocity of the second arm  13  including the vibrational component of the third arm  14  can be detected by the second angular velocity sensor  32  in the second arm  13 , and it is possible to increase the effect of suppressing vibration of the robot  1 . 
     The second arm  13  has an arm-side attachment portion  131  which is formed integrally with the arm body  2   b  and to which the second angular velocity sensor unit  72  (second housing  721 ) is attached. In each corner portion of the arm-side attachment portion  131 , a threaded bore into which the screw  81  is threaded is formed. 
     When attaching the second angular velocity sensor unit  72  to the second arm  13 , the four screws  81  are respectively inserted into the holes  7212  of the second housing  721  and threaded into the threaded bores in the front end portion of the arm-side attachment portion  131  of the second arm  13 . With this, the four attachment portions  7211  of the second housing  721  are fixed to the arm-side attachment portion  131  of the second arm  13  by the screws  81 . That is, the second angular velocity sensor unit  72  is attached to the arm-side attachment portion  131  of the second arm  13 . In this case, there is nothing between the arm-side attachment portion  131  and the second angular velocity sensor unit  72 , that is, the second angular velocity sensor unit  72  is directly attached to the arm-side attachment portion  131 . Accordingly, it is possible to attach the second angular velocity sensor unit  72  to the second arm  13  reliably, and to allow the second angular velocity sensor unit  72  to rotate integrally with the second arm  13  reliably. 
     If the screws  81  are inserted into the holes  7212  of the second housing  721  and threaded into the threaded bores of the arm-side attachment portion  131 , the screws  81  are electrically connected to the wiring of the circuit board  722  electrically connected to the ground terminal of the circuit unit  723 , and the front end portions of the screws  81  are electrically connected to the arm-side attachment portion  131 . With this, the ground terminal of the circuit unit  723  is electrically connected to the arm body  2   b  of the second arm through the wiring and the screws  81  and grounded. Accordingly, it is possible to reduce the number of components for grounding and to simplify the configuration. 
     The second angular velocity sensor unit  72  is provided such that the detection axis  32   a  of the second angular velocity sensor  32  inclined with respect to the second rotating axis O 2  at a predetermined angle (third angle) θ3. It should suffice that the angle θ 3  is equal to or greater than 0° and smaller than 90° (0°≦θ 3 &lt;90°). If θ 3 =0°, the detection axis  32   a  of the second angular velocity sensor  32  matches the second rotating axis O 2 . For this reason, the angular velocity detected by the second angular velocity sensor  32  substantially matches the angular velocity around the second rotating axis O 2  of the second arm  13 . Accordingly, it is possible to detect the angular velocity around the second rotating axis O 2  of the second arm  13  without substantially correcting the angular velocity detected by the second angular velocity sensor  32 . 
     If 0°&lt;θ 3 &lt;90°, the detection axis  32   a  of the second angular velocity sensor  32  is inclined with respect to the second rotating axis O 2 . For this reason, the angular velocity detected by the second angular velocity sensor  32  is deviated from the angular velocity around the second rotating axis O 2  of the second arm  13 . However, if the angle θ 3  is set to a predetermined angle in advance, it is possible to detect the angular velocity around the second rotating axis O 2  of the second arm  13  accurately by correcting the angular velocity detected by the second angular velocity sensor  32  on the basis of the angle θ 3 . The correction at this time is a simple computation, and complicated and enormous computation is not required. For this reason, a computation error is less likely to occur, and it is possible to reliably suppress vibration and to increase a response speed in the control of the robot  1 . 
     For example, as shown in  FIG. 19 , a first axis J1″ parallel to the second rotating axis O 2 , a second axis J2″ orthogonal to the first axis J1″, and a third axis J3″ orthogonal to both the first axis J1″ and the second axis J2″ are set, and when the angle around the second axis J2″ of the detection axis  32   a  is α 3 , the angle around the third axis J3″ of the detection axis  32   a  is β 3 , and the angular velocity which is detected by the second angular velocity sensor  32  is ω 3 , ω 3  cos α 3  cos β 3  is set as the angular velocity around the second rotating axis O 2  of the second arm  13 . In order to secure high correction precision, it is preferable that θ 3  is as small as possible, and specifically, satisfies the range of 0°&lt;θ 3 ≦15°. When this range is satisfied, it is possible to detect the angular velocity around the second rotating axis O 2  of the second arm  13  with higher precision. However, the correction method is not limited to the above-described method. 
     In recent years, with the advancement of reduction in size and weight of the robot  1 , there is a case where the second angular velocity sensor  32  cannot be arranged at θ 3 =0° depending on the internal space of the second arm  13 . In this case, the second angular velocity sensor  32  is arranged in the second arm  13  such that θ 3  becomes a desired angle, whereby it is possible to detect the angular velocity around the second rotating axis O 2  of the second arm  13  with high precision. 
     Next, the configuration of the robot control device  20  will be described referring to  FIGS. 20 and 21 . However, the driving source control units  201 ,  204 ,  205 , and  206  are the same as those in the above-described first embodiment, and thus, description thereof will not be repeated. 
     As shown in  FIG. 20 , the second driving source control unit  202  has a subtracter  512 , a position control unit  522 , a subtracter  532 , an angular velocity control unit  542 , a rotation angle calculation unit  552 , an angular velocity calculation unit  562 , a subtracter  572 , a conversion unit  582 , a correction value calculation unit  592 , and an adder  602 . 
     In addition to the position command Pc of the second driving source  402 , the detection signals from the second position sensor  412  and the second angular velocity sensor  32  (correction unit  612 ) are input to the second driving source control unit  202 . The second driving source control unit  202  drives the second driving source  402  by feedback control using the respective detection signals such that the rotation angle (position feedback value Pfb) of the second driving source calculated from the detection signal of the second position sensor  412  becomes the position command Pc and a below-described angular velocity feedback value ωfb becomes a below-described angular velocity command ωc. 
     That is, the position command Pc and a below-described position feedback value Pfb from the rotation angle calculation unit  552  are input to the subtracter  512  of the second driving source control unit  202 . In the rotation angle calculation unit  552 , the number of pulses input from the second position sensor  412  is counted, and the rotation angle of the second driving source  402  according to the count value is output to the subtracter  512  as the position feedback value Pfb. The subtracter  512  outputs the deviation (the value obtained by subtracting the position feedback value Pfb from a target value of the rotation angle of the second driving source  402 ) between the position command Pc and the position feedback value Pfb to the position control unit  522 . 
     The position control unit  522  performs predetermined calculation processing using the deviation input from the subtracter  512 , and a proportional gain or the like as a preset coefficient, and calculates the target value of the angular velocity of the second driving source  402  according to the deviation. The position control unit  522  outputs a signal representing the target value (command value) of the angular velocity of the second driving source  402  to the subtracter  532  as the angular velocity command ωc. Here, in this embodiment, although proportional control (P control) is performed as feedback control, the invention is not limited thereto. 
     The angular velocity command ωc and a below-described angular velocity feedback value ωfb are input to the subtracter  532 . The subtracter  532  outputs the deviation (the value obtained by subtracting the angular velocity feedback value ωfb from the target value of the angular velocity of the second driving source  402 ) between the angular velocity command ωc and the angular velocity feedback value ωfb to the angular velocity control unit  542 . 
     The angular velocity control unit  542  performs predetermined calculation processing including integration using the deviation input from the subtracter  532 , and a proportional gain, an integral gain, and the like as preset coefficients, produces a driving signal (driving current) of the second driving source  402  according to the deviation, and supplies the driving signal to the motor  402 M through the motor driver  302 . Here, in this embodiment, although PI control is performed as feedback control, the invention is not limited thereto. 
     In this way, the feedback control is performed such that the position feedback value Pfb becomes equal to the position command Pc as much as possible and the angular velocity feedback value ωfb becomes equal to the angular velocity command ωc as much as possible, and the driving current of the second driving source  402  is controlled. 
     Next, the angular velocity feedback value ωfb in the second driving source control unit  202  will be described. 
     In the angular velocity calculation unit  562 , an angular velocity ωm 2  of the second driving source  402  is calculated on the basis of the frequency of a pulse signal input from the second position sensor  412 , and the angular velocity ωm 2  is output to the adder  602 . 
     In the angular velocity calculation unit  562 , an angular velocity ωA 2  m around the second rotating axis O 2  of the second arm  13  is calculated on the basis of the frequency of the pulse signal input from the second position sensor  412 , and the angular velocity ωA 2  m is output to the subtracter  572 . The angular velocity ωA 2  m is a value obtained by dividing the angular velocity ωm 2  by a reduction ratio between the motor  402 M of the second driving source  402  and the second arm  13 , that is, in the joint  172 . 
     An angular velocity ωA 2 ′ corresponding to the rotation around the second rotating axis O 2  of the second arm  13  is detected by the second angular velocity sensor  32 , and the detected angular velocity ωA 2 ′ is output to the correction unit  612 . For example, the correction unit  612  multiplies the angular velocity ωA 2 ′ input from the second angular velocity sensor  32  by cos α 2  cos β 2 . ωA 2 ′ cos α 2  cos β 2  is output to the adder-subtracter  572  as an angular velocity ωA 2  around the second rotating axis O 2  of the second arm  13 . However, if θ 2 =0°, since ωA 2 ′=ωA 2 , correction by the correction unit  612  is not required, and the correction unit  612  may be omitted. 
     Since the second rotating axis O 2  is orthogonal to the first rotating axis O 1 , it is possible to obtain the angular velocity around the second rotating axis O 2  of the second arm  13  easily and reliably without being affected by operation or vibration of the first arm  12 . 
     The angular velocity ωA 2  and the angular velocity ωA 2  m are input to the subtracter  572 , and the subtracter  572  outputs a value ωA 2  s (=ωA 2  −ωA 2 m) obtained by subtracting the angular velocity ωA 2  m from the angular velocity ωA 2  to the conversion unit  582 . As described above, since the second angular velocity sensor  32  also detects the vibrational component of the angular velocity of the third arm  14 , the value ωA 2  s corresponds to the total of the vibrational component (vibrational angular velocity) of the angular velocity around the second rotating axis O 2  of the second arm  13  and the vibrational component (vibrational angular velocity) of the angular velocity around the third rotating axis O 3  of the third arm  14 . Hereinafter, ωA 2  s is referred to as a vibrational angular velocity. In this embodiment, feedback control is performed to return a below-described gain Ka multiple of the vibrational angular velocity ωA 2  s (in detail, an angular velocity ωm 2  s in the motor  402 M which is a value produced on the basis of the vibrational angular velocity ωA 2  s) to the input side of the second driving source  402 . Specifically, the feedback control is performed on the second driving source  402  such that the vibrational angular velocity ωA 2  s becomes close to 0 as much as possible. Accordingly, it is possible to suppress vibration of the robot  1 . In the feedback control, the angular velocity of the second driving source  402  is controlled. 
     The conversion unit  582  converts the vibrational angular velocity ωA 2  s to the angular velocity ωm 2  s in the second driving source  402 , and outputs the angular velocity ωm 2  s to the correction value calculation unit  592 . The conversion can be performed by multiplying the vibrational angular velocity ωA 2  s by a reduction ratio between the motor  402 M of the second driving source  402  and the second arm  13 , that is, in the joint  172 . 
     The correction value calculation unit  592  multiplies the angular velocity ωm 2  s by the gain (feedback gain) Ka as a preset coefficient, obtains a correction value Ka·ωm 2  s, and outputs the correction value Ka·ωm 2  s to the adder  602 . 
     The angular velocity ωm 2  and the correction value Ka·ωm 2  s are input to the adder  602 . The adder  602  outputs the sum of the angular velocity ωm 2  and the correction value Ka·ωm 2  s to the subtracter  532  as the angular velocity feedback value ωfb. A subsequent operation is as described above. 
     As shown in  FIG. 21 , the third driving source control unit  203  has a subtracter  513 , a position control unit  523 , a subtracter  533 , an angular velocity control unit  543 , a rotation angle calculation unit  553 , and an angular velocity calculation unit  563 . 
     In addition to the position command Pc of the third driving source  403 , the detection signal from the third position sensor  413  is input to the third driving source control unit  203 . The third driving source control unit  203  drives the third driving source  403  by feedback control using the respective detection signals such that the rotation angle (position feedback value Pfb) of the third driving source  403  calculated from the detection signal of the third position sensor  413  becomes the position command Pc and a below-described angular velocity feedback value ωfb becomes a below-described angular velocity command ωc. 
     That is, the position command Pc and a below-described position feedback value Pfb from the rotation angle calculation unit  553  are input to the subtracter  513  of the third driving source control unit  203 . In the rotation angle calculation unit  553 , the number of pulses input from the third position sensor  413  is counted, and the rotation angle of the third driving source  403  according to the count value is output to the subtracter  513  as the position feedback value Pfb. The subtracter  513  outputs the deviation (the value obtained by subtracting the position feedback value Pfb from a target value of the rotation angle of the third driving source  403 ) between the position command Pc and the position feedback value Pfb to the position control unit  523 . 
     The position control unit  523  performs predetermined calculation processing using the deviation input from the subtracter  513 , and a proportional gain or the like as a preset coefficient, and calculates a target value of the angular velocity of the third driving source  403  according to the deviation. The position control unit  523  outputs a signal representing the target value (command value) of the angular velocity of the third driving source  403  to the subtracter  533  as the angular velocity command ωc. Here, in this embodiment, although proportional control (P control) is performed as feedback control, the invention is not limited thereto. 
     In the angular velocity calculation unit  563 , the angular velocity of the third driving source  403  is calculated on the basis of the frequency of a pulse signal input from the third position sensor  413 , and the angular velocity is output to the subtracter  533  as the angular velocity feedback value ωfb. 
     The angular velocity command ωc and the angular velocity feedback value ωfb are input to the subtracter  533 . The subtracter  533  outputs the deviation (the value obtained by subtracting the angular velocity feedback value ωfb from the target value of the angular velocity of the third driving source  403 ) between the angular velocity command ωc and the angular velocity feedback value ωfb to the angular velocity control unit  543 . 
     The angular velocity control unit  543  performs predetermined calculation processing including integration using the deviation input from the subtracter  533 , and a proportional gain, an integral gain, and the like as preset coefficients, produces a driving signal (driving current) of the third driving source  403  according to the deviation, and supplies the driving signal to the motor  403 M through the motor driver  303 . Here, in this embodiment, although PI control is performed as feedback control, the invention is not limited thereto. 
     In this way, the feedback control is performed such that the position feedback value Pfb becomes equal to the position command Pc as much as possible and the angular velocity feedback value ωfb becomes equal to the angular velocity command ωc as much as possible, and the driving current of the third driving source  403  is controlled. 
     According to the third embodiment, the same effects as the above-described first embodiment can also be exhibited. 
     Although the robot, the robot control device, and the robot system of the invention have been described on the basis of the illustrated embodiments, the invention is not limited to the embodiments, and the configuration of each unit can be substituted with an arbitrary configuration having the same function. Other arbitrary constituent components may be added to the invention. 
     As the motor of each driving source, in addition to the servomotor, for example, a stepping motor or the like may be used. If a stepping motor is used as the motor, as a position sensor, for example, a position sensor which measures the number of driving pulses input to the stepping motor so as to detect the rotation angle of the motor may be used. 
     The type of each position sensor or each angular velocity sensor is not particularly limited, and for example, an optical type, a magnetic type, an electromagnetic type, an electrical type, or the like may be used. 
     In the foregoing embodiments, although the actuation of the second driving source rotating the second arm is controlled on the basis of the detection result of the second angular velocity sensor, the invention is not limited thereto, and for example, the actuation of the third driving source rotating the third arm may be controlled on the basis of the detection result of the second angular velocity sensor. 
     In the foregoing embodiments, although the number of rotating axes of the robot is six, the invention is not limited thereto, and the number of rotating axes of the robot may be three, four, five, or seven or more. 
     That is, in the foregoing embodiments, although, since the wrist has two arms, the number of arms of the robot is six, the invention is not limited thereto, and the number of arms of the robot may be three, four, five, or seven or more. 
     In the foregoing embodiments, although the robot is a single-arm robot which has an arm connector with a plurality of arms rotatably connected together, the invention is not limited thereto, and for example, the robot may be a robot having a plurality of arm connectors, for example, a double-arm robot which has two arm connectors with a plurality of arms rotatably connected together, or the like.