Robot system

Abstract

The utility model provides a robot system which can detect which joint vibrates and can control effective vibration. A robot system includes: a robot including a robot arm including a plurality of arms and a plurality of joints including a base-end-side joint having mutually parallel rotation axes and a tip-end-side joint located on the tip-end side of the base-end-side joint; and an inertial sensor disposed on the arm connecting the distal end-side joint and the joint located on the distal end side prior to the distal end-side joint. The inertial sensor detects an angular velocity about an axis parallel to the rotation axis and an acceleration in a direction orthogonal to the center axis of the arm on which the inertial sensor is disposed and orthogonal to the rotation axis.

Description

TECHNICAL FIELD

[0001] The utility model relates to robot system. BACKGROUND

[0002] The manipulator described in Patent Document 1 has: an arm having a plurality of joints; an actuator disposed at each joint; an end effector connected to the front end portion of the arm; and an acceleration sensor disposed at the end effector. In the manipulator thus configured, the vibration of the end effector is detected by the acceleration sensor, and the vibration is controlled based on the detection result.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2022-177607

[0004] However, in the manipulator of Patent Document 1, it is not possible to determine which of the plurality of joints possessed by the arm caused the vibration of the end effector. Therefore, it is difficult to control the effective vibration. SUMMARY

[0005] The robot system of the utility model has:

[0006] Robot, possess mechanical arm, the mechanical arm includes multiple arms and multiple joints, the multiple joints include the base end side joint with the parallel rotation axis each other and the front end side joint in the front end side of the base end side joint, and

[0007] Inertial sensor, configure in the arm that links the front end side joint with the joint in the front one front end side of the front end side joint,

[0008] The inertial sensor detects the angular velocity around the axis parallel with the rotation axis and the acceleration in the direction orthogonal with the central axis of the arm where the inertial sensor is disposed and orthogonal with the rotation axis.

[0009] The robot system of the utility model has:

[0010] Robot, possess mechanical arm, the mechanical arm includes multiple arms and multiple joints, the multiple joints include the base end side joint with the parallel rotation axis each other and the front end side joint in the front end side of the base end side joint, and

[0011] Inertial sensor, configure in the arm that links the joint in the front one front end side of the front end side joint with the joint in the again front one front end side,

[0012] The inertial sensor detects the angular velocity around the axis parallel with the rotation axis and the acceleration in the direction orthogonal with the central axis of the arm where the inertial sensor is disposed and orthogonal with the rotation axis.

[0013] The robot system has:

[0014] The robot has a robot arm, the robot arm includes a plurality of arms and a plurality of joints, the plurality of joints include a base end side joint having mutually parallel rotation axes and a front end side joint located on a front end side of the base end side joint, and

[0015] An inertial sensor is arranged on the arm between the front end side joint and the joint located on the most front end side,

[0016] The inertial sensor detects an angular velocity around an axis parallel to the rotation axis and an acceleration in a direction orthogonal to a central axis of the arm in which the inertial sensor is arranged and orthogonal to the rotation axis.

[0017] Also, the robot has a base,

[0018] The robot has a base,

[0019] The robot arm has a first arm, a second arm and a third arm, the first arm is connected with the base via the joint different from the base end side joint and the front end side joint, the second arm is connected with the first arm via the base end side joint, and the third arm is connected with the second arm via the front end side joint,

[0020] The inertial sensor is arranged on the third arm.

[0021] Also, the robot has a base,

[0022] When viewed from a direction orthogonal to the rotation axis and the central axis of the third arm, the inertial sensor is located on the central axis of the third arm.

[0023] Also, the robot has a base,

[0024] The inertial sensor is arranged on the end of the third arm opposite to the front end side joint.

[0025] Also, the robot has a base,

[0026] The robot has a driving source arranged in the third arm and driving the robot arm,

[0027] The inertial sensor is arranged separately from the driving source.

[0028] Also, the robot has a base,

[0029] The inertial sensor is arranged in the third arm.

[0030] Also, the robot has a base,

[0031] The inertial sensor is arranged on the wall of the third arm.

[0032] Also, the robot system can be configured to include a robot having a base,

[0033] The wall portion has an inner wall, an outer wall, and a hollow portion between the inner wall and the outer wall,

[0034] The inertial sensor is disposed in the hollow portion.

[0035] Also, the robot system can be configured to include a robot having a base,

[0036] The robot has a base,

[0037] The robot has a base,

[0038] The inertial sensor is disposed in the hollow portion.

[0039] The inertial sensor detects angular velocity around two axes orthogonal to the rotation axis of the fourth arm and to each other and acceleration in the direction of two axes orthogonal to the rotation axis of the fourth arm and to each other.

[0040] Also, the robot system can be configured to include a robot having a base,

[0041] The inertial sensor is disposed in the hollow portion.

[0042] Also, the robot system can be configured to include a robot having a base,

[0043] The robot has a base,

[0044] The robot has a base,

[0045] The inertial sensor is disposed in the hollow portion. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 is a whole view of a robot system according to a first embodiment.

[0047] Figure 2 is a view showing a posture in which the amount of vibration of each of the second and third joints cannot be detected based on acceleration alone.

[0048] Figure 3 is a schematic view showing a posture in which the amount of vibration of each of the second and third joints cannot be detected from the angular velocity alone.

[0049] Figure 4 is a flowchart showing a control procedure of the robot.

[0050] Figure 5 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0051] Figure 6 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0052] Figure 7 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0053] Figure 8 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0054] Figure 9 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0055] Figure 10 is a schematic view for explaining a method of detecting the amount of vibration of each of the second and third joints.

[0056] Figure 11 is a block diagram showing a configuration of a control section possessed by the control device.

[0057] Figure 12 is a view showing an example of the configuration of the inertial sensor.

[0058] Figure 13 is a view showing an example of the configuration of the inertial sensor.

[0059] Figure 14 is a view showing an example of the configuration of the inertial sensor.

[0060] Figure 15 is a view showing an example of the configuration of the inertial sensor.

[0061] Figure 16 is a schematic view showing a robot according to the second embodiment.

[0062] Figure 17 is a view showing the configuration of the inertial sensor.

[0063] Figure 18 is a schematic view showing a robot according to the third embodiment.

[0064] Figure 19 is a schematic view showing a robot according to the fourth embodiment.

[0065] Figure 20 is a schematic view showing a robot according to the fifth embodiment.

[0066] Figure 21 is a view showing a robot according to the sixth embodiment.

[0067] Legend of reference symbols

[0068] 1: robot system; 2: robot; 21: base; 22: robot arm; 221: first arm; 222: second arm; 223: third arm; 223a: frame; 223b: cover; 223c: inner wall; 223d: outer wall; 223e: hollow portion; 224: fourth arm; 225: fifth arm; 226: sixth arm; 227: seventh arm; 231: first joint; 232: second joint; 233: third joint; 234: fourth joint; 235: fifth joint; 236: sixth joint; 237: seventh joint; 24: end effector; 3: inertial sensor; 31a: angular velocity detection element; 31b: angular velocity detection element; 31c: angular velocity detection element; 31d: angular velocity detection element; 32a: acceleration detection element; 32b: acceleration detection element; 4: control device; 40: control section; 41: position command generation section; 42: position control section; 43: speed control section; 44: current control section; 45: vibration feedback generation section; 5: robot; 51: base; 52: robot arm; 521: first arm; 522: second arm; 53: work head; 531: spline nut; 532: ball screw nut; 533: spline shaft; 533a: fitting portion; 541: first joint; 542: second joint; 901: position command; 902: motor shaft position; 903: position deviation; 904: speed command; 905: speed loop command; 906: current command; 907: current; 912: motor shaft conversion arm angular velocity; 913: motor shaft angular velocity; 914: vibration angular velocity; 915: vibration feedback; A: center axis; Axs: acceleration; Azs: acceleration; E: encoder; J1: first rotation axis; J2: second rotation axis; J3: third rotation axis; J4: fourth rotation axis; J5: fifth rotation axis; J6: sixth rotation axis; J7: seventh rotation axis; J11: first rotation axis; J12: second rotation axis; J13: third rotation axis; Kgp: feedback gain; Kgs: arm angular velocity scaling coefficient; Kpp: position loop proportional gain; Kvi: speed loop integral gain; Kvp: speed loop proportional gain; L2: interval distance; L3: interval distance; M: motor; S1: inertial information acquisition step; S2: vibration detection step; S3: drive control step; Vxs: translational velocity; Vzs: translational velocity; ω: angular velocity; ω2: angular velocity; ω3: angular velocity; ωs: angular velocity. DETAILED DESCRIPTION

[0069] Hereinafter, the robot system of the present application will be described in detail based on the embodiment shown in the drawings.

[0070] First Embodiment

[0071] Figure 1 is a general view of the robot system involved in the first embodiment.Figure 2 is a schematic view showing a posture in which the amount of vibration of each of the second and third joints cannot be detected based on the acceleration alone. Figure 3 is a schematic view showing a posture in which the amount of vibration of each of the second and third joints cannot be detected based on the angular velocity alone. Figure 4 is a flowchart showing a control procedure of the robot. Figures 5 to 10 are schematic views for explaining a method of detecting the amount of vibration of each of the second and third joints, respectively. Figure 11 is a block diagram showing the configuration of a control section possessed by the control device. Figures 12 to 15 are diagrams showing examples of the arrangement of the inertial sensor, respectively.

[0072] Figure 1 The robot system 1 shown has a robot 2, an inertial sensor 3 arranged on the robot 2, and a control device 4 that controls the driving of the robot 2.

[0073] The robot 2 is a six-axis vertical multi-joint robot having six driving axes, and has a base 21 and a robot arm 22 that is connected to the base 21 in a rotatable manner. The robot arm 22 is configured so that first, second, third, fourth, fifth, and sixth arms 221, 222, 223, 224, 225, and 226 are connected via first, second, third, fourth, fifth, and sixth joints 231, 232, 233, 234, 235, and 236. Here, the joint located on the front end side next to the first joint 231 is the second joint 232, the joint located on the front end side next to the second joint 232 is the third joint 233, the joint located on the front end side next to the third joint 233 is the fourth joint 234, the joint located on the front end side next to the fourth joint 234 is the fifth joint 235, and the joint located on the front end side next to the fifth joint 235 is the sixth joint 236.

[0074] The first arm 221 is connected to the base 21 via the first joint 231 in a rotatable manner about a first rotation axis Jl. In addition, the second arm 222 is connected to the first arm 221 via the second joint 232 in a rotatable manner about a second rotation axis J2. In addition, the third arm 223 is connected to the second arm 222 via the third joint 233 in a rotatable manner about a third rotation axis J3. In addition, the fourth arm 224 is connected to the third arm 223 via the fourth joint 234 in a rotatable manner about a fourth rotation axis J4. In addition, the fifth arm 225 is connected to the fourth arm 224 via the fifth joint 235 in a rotatable manner about a fifth rotation axis J5. In addition, the sixth arm 226 is connected to the fifth arm 225 via the sixth joint 236 in a rotatable manner about a sixth rotation axis J6.

[0075] Further, the second, third, and fifth joints 232, 233, 235 among the joints 231, 232, 233, 234, 235, 236 are respectively a bend joint, and the first, fourth, and sixth joints 231, 234, 236 are respectively a twist joint. Further, the second rotation axis J2 is orthogonal to the first rotation axis Jl, the third rotation axis J3 is parallel to the second rotation axis J2, the fourth rotation axis J4 is orthogonal to the third rotation axis J3, the fifth rotation axis J5 is orthogonal to the fourth rotation axis J4, and the sixth rotation axis J6 is orthogonal to the fifth rotation axis J5. Further, the second, third, and fifth rotation axes J2, J3, J5 are respectively oriented in a horizontal direction.

[0076] Note that, in the present application, "parallel" includes not only the case where the axes are parallel to each other, but also the case where a deviation occurs with respect to parallelism to such a degree that it can be regarded as parallel from a technical common sense viewpoint, for example. Further, "orthogonal" includes not only the case where the axes are orthogonal to each other, but also the case where a deviation occurs with respect to orthogonality to such a degree that it can be regarded as orthogonal from a technical common sense viewpoint, for example.

[0077] In such a robot 2, the second joint 232 is the "base end side joint" of the present application, and the third joint 233 is the "front end side joint" of the present application.

[0078] Further, each joint 231, 232, 233, 234, 235, 236 has a motor M, a reducer (not shown) that reduces the rotation speed of the motor M and outputs, and an encoder E that detects the rotation amount of the motor M. The control device 4 controls the rotation amount of each joint 231, 232, 233, 234, 235, 236 by driving the motor M through servo control that feeds back the output of the encoder E.

[0079] Further, a terminal executor 24 is attached to the front end portion of the robot arm 22, that is, the sixth arm 226. The terminal executor 24 is detachably attached to the sixth arm 226, and is appropriately attached in accordance with the work content performed by the robot 2.

[0080] Further, as Figure 1As shown, the inertial sensor 3 is disposed in the third arm 223. The inertial sensor 3 has an angular velocity detection element 31a that detects an angular velocity ωs around an axis in the same orientation as the second and third rotational axes J2, J3, and an acceleration detection element 32a that detects an acceleration Azs in a direction orthogonal to the central axis A of the third arm 223 and orthogonal to the second and third rotational axes J2, J3. In detail, the acceleration Azs is an acceleration in the vertical direction that is generated by a whirling motion of the third arm 223 that is generated by driving of at least one of the second and third joints 232, 233. By disposing the inertial sensor 3 in the third arm 223, the detection axis of the angular velocity detection element 31a is maintained in a state parallel to the second and third rotational axes J2, J3 and the detection axis of the acceleration detection element 32a is maintained in a state orthogonal to the second and third rotational axes J2, J3 at any posture, so the angular velocity ωs and the acceleration Azs can be detected more reliably.

[0081] As described above, since the inertial sensor 3 is disposed in the third arm 223, it can be said that the inertial sensor 3 is disposed in an arm between the third joint 233 that is the joint on the front end side and the sixth joint 236 that is the joint on the foremost end side. In other words, it can be said that the inertial sensor 3 is not disposed in the sixth arm 226. In this way, by avoiding disposition of the inertial sensor 3 in the arm on the foremost end, the number of joints between the inertial sensor 3 and the third joint 233 can be suppressed to be as small as possible. Therefore, the angular velocity ωs and the acceleration Azs can be detected easily without being affected by the posture of the robot arm 22.

[0082] In the present embodiment, as the inertial sensor 3, one sensor unit having the angular velocity detection element 31a and the acceleration detection element 32a is used, but it is not limited thereto, and the angular velocity sensor having the angular velocity detection element 31a and the acceleration sensor having the acceleration detection element 32a can be disposed separately.

[0083] The control device 4 controls driving of the robot 2. The control device 4 is constituted by, for example, a computer, and has a processor (CPU) that processes information, a memory that is connected to the processor in a communicable manner, and an external interface that performs connection with an external device. Various programs that can be executed by the processor are stored in the memory, and the processor can read and execute the programs and the like stored in the memory.

[0084] The configuration of the robot system 1 is described above. For example, as shown in Figure 2 In a case where the inertial sensor 3 can detect only the acceleration Azs, the angular velocity ω2 based on vibration of the second joint 232 and the angular velocity ω3 based on vibration of the third joint 233 cannot be distinguished when the second and third arms 222, 223 are extended together in the horizontal direction. In addition, for example, as shown in Figure 3As shown in the drawing, in a case where the inertial sensor 3 can only detect the angular velocity ωs, in a posture where the second arm 222 is oriented in the vertical direction and the third arm 223 is oriented in the horizontal direction and they are orthogonal, it is not possible to distinguish the angular velocity ω2 based on the vibration of the second joint 232 from the angular velocity ω3 based on the vibration of the third joint 233. In view of this, in the robot system 1, the inertial sensor 3 is able to detect the angular velocity ωs and the acceleration Azs, and is able to distinguish the vibration of the second joint 232 from the vibration of the third joint 233 based on the relationship between the angular velocity ωs and the acceleration Azs. Hereinafter, the method will be described.

[0085] As shown in the drawing, the control method of the robot 2 includes: an inertial information acquisition step S1 of acquiring the angular velocity ωs and the acceleration Azs from the inertial sensor 3; a vibration detection step S2 of detecting the amount of vibration of each of the joints of the second joint 232 and the third joint 233 based on the angular velocity ωs and the acceleration Azs acquired in the inertial information acquisition step S1; and a drive control step S3 of controlling the vibration based on the detection result of the vibration detection step S2 and based on the amount of vibration of each joint. Hereinafter, each of the steps S1 to S3 will be described in detail. Figure 4 The inertial information acquisition step S1

[0086] In the inertial information acquisition step S1, the control device 4 acquires the angular velocity ωs and the acceleration Azs from the inertial sensor 3.

[0087] The vibration detection step S2

[0088] In the vibration detection step S2, the control device 4 detects the amount of vibration of each of the joints of the second joint 232 and the third joint 233 based on the angular velocity ωs and the acceleration Azs acquired in the inertial information acquisition step S1.

[0089] As one example, as shown in the drawing, a detection method in a posture where the second arm 222 and the third arm 223 are straight in the horizontal direction will be described. Note that, as described above, in this posture, it is not possible to detect the amount of vibration of each of the joints of the second joint 232 and the third joint 233 only from the acceleration Azs. In addition, as shown in the drawing, the distance between the second rotation axis J2 and the third rotation axis J3 is set to L2, and the distance between the third rotation axis J3 and the inertial sensor 3 is set to L3. In a case where the second joint 232 vibrates, the inertial sensor 3 detects the angular velocity ω2 and the acceleration Azs. In a case where the third joint 233 vibrates, the inertial sensor 3 detects the angular velocity ω3 and the acceleration Azs.

[0090] In a case where the second joint 232 vibrates, the inertial sensor 3 detects the angular velocity ω2 and the acceleration Azs. In a case where the third joint 233 vibrates, the inertial sensor 3 detects the angular velocity ω3 and the acceleration Azs. Figure 5 Figure 5 In a case where the second joint 232 vibrates, the inertial sensor 3 detects the angular velocity ω2 and the acceleration Azs. In a case where the third joint 233 vibrates, the inertial sensor 3 detects the angular velocity ω3 and the acceleration Azs. ​

[0091] As Figure 6 shown, when the second joint 232 vibrates at an angular velocity ω2, Vzs = (L2 + L3) x ω2, ω = ω2. On the other hand, as Figure 7 shown, when the third joint 233 vibrates at an angular velocity ω3, Vzs = L3 x ω3, ω = ω3. In this way, the relationship between the translational velocity Vzs and the angular velocity ω differs when the second joint 232 vibrates and when the third joint 233 vibrates. Specifically, Vzs / ω when the second joint 232 vibrates is greater than Vzs / ω when the third joint 233 vibrates. Therefore, based on the relationship between the translational velocity Vzs and the angular velocity ω, it is possible to determine the amount of vibration of each of the second joint 232 and the third joint 233.

[0092] According to the above relationship, the following equations (1) and (2) using the Jacobian matrix hold. Therefore, it is possible to calculate the angular velocities ω2, ω3 based on L2, L3, the angular velocity ωs detected by the inertial sensor 3, and the translational velocity Vzs calculated from the acceleration Azs detected by the inertial sensor 3. Further, it is possible to determine the amount of vibration of each of the second joint 232 and the third joint 233 based on the values of the calculated angular velocities ω2, ω3.

[0093] [Equation 1]

[0094]

[0095] [Equation 2]

[0096]

[0097] Further, as another example, as Figure 8 shown, a posture in which the second arm 222 is oriented in the vertical direction and the third arm 223 is oriented in the horizontal direction and the second and third arms 222, 223 are orthogonal is described. At this time, the vertical direction interval distance from the center of the third arm 222 to the detection center of the acceleration detected by the inertial sensor 3 is set to Lsz. Note that, as described above, in this posture, it is not possible to detect the amount of vibration of each of the second joint 232 and the third joint 233 based on only the angular velocity ωs.

[0098] As Figure 9 shown, when the second joint 232 vibrates at an angular velocity ω2, Vzs = L3 x ω2, ω = ω2. On the other hand, as Figure 10 shown, when the third joint 233 vibrates at an angular velocity ω3, Vzs = √(L3 2 +Lsz 2) x ω3, ω = ω3. Thus, the relationship between the translational velocity Vzs and the angular velocity ω differs when the second joint 232 vibrates and when the third joint 233 vibrates. Therefore, based on the relationship between the translational velocity Vzs and the angular velocity ω, it is possible to determine the vibration amount of each of the second joint 232 and the third joint 233.

[0099] According to the above relationship, the following equation (3) and equation (4) using the Jacobian matrix hold. Therefore, it is possible to calculate the angular velocities ω2, ω3 based on the previously measured L2, L3, Lsz, the angular velocity ωs detected by the inertial sensor 3, and the translational velocity Vzs calculated from the acceleration Azs detected by the inertial sensor 3. Further, it is possible to determine the vibration amount of each of the second joint 232 and the third joint 233 based on the values of the calculated angular velocities ω2, ω3.

[0100] [Equation 3]

[0101]

[0102] [Equation 4]

[0103]

[0104] In the above, for the representative two postures in which it is not possible to determine the vibration amount of each of the second joint 232 and the third joint 233 based on either one of the angular velocity ωs and the acceleration Azs, of course, in other postures as well, it is possible to determine the vibration amount of each of the second joint 232 and the third joint 233 based on the relationship between the angular velocity ωs and the acceleration Azs.

[0105] In the robot 2, the following equation (5) and equation (6) using the Jacobian matrix J also hold in any posture. Note that the Jacobian matrix J indicates the position of the inertial sensor 3 and is a value that differs depending on the rotation amount of the second and third joints 232, 233. The position of the inertial sensor 3 is detected, for example, based on the output of the encoders E provided to the second and third joints 232, 233. Therefore, it is possible to calculate the angular velocities ω2, ω3 based on the previously measured interval distances L2, L3, Lsz, the angular velocity ωs detected by the inertial sensor 3, and the translational velocity Vzs calculated from the acceleration Azs detected by the inertial sensor 3. Further, it is possible to determine the vibration amount of each of the second joint 232 and the third joint 233 based on the values of the calculated angular velocities ω2, ω3.

[0106] [Equation 5]

[0107]

[0108] [Equation 6]

[0109]

[0110] According to the method described above, the vibration amount of each joint of the second joint 232 and the third joint 233 can be determined. In particular, the vibration amount of each joint of the second joint 232 and the third joint 233 can be determined based on the pre-measured interval distances L2, L3, Lsz, the angular velocity ωs detected by the inertial sensor 3, and the translational velocity Vzs calculated based on the acceleration Azs detected by the inertial sensor 3, thus making this detection easy to perform.

[0111] Drive control step S3

[0112] In the drive control step S3, the control device 4 controls the drive of the robotic arm 22 based on the detection results of the vibration detection step S2. Specifically, the control device 4 controls the second joint 232 and the third joint 233 based on the vibration amount of each joint determined in the vibration detection step S2. In this way, by controlling the vibration based on the vibration amount of each joint, more appropriate control can be achieved, and vibration can be reduced more reliably and effectively.

[0113] For example, if we take the control of the second joint 232 as an example, then... Figure 11 As shown, the control device 4 has a control unit 40 that controls the drive of the second joint 232. Furthermore, the control unit 40 includes: a position command generation unit 41, a position control unit 42, a speed control unit 43, a current control unit 44, and a vibration feedback generation unit 45.

[0114] The vibration feedback generation unit 45 multiplies the vibration quantity (angular velocity ω) determined in step S2 based on the angular velocity ωs and acceleration Azs detected by the inertial sensor 3 by the arm angular velocity scale coefficient Kgs to obtain the motor shaft equivalent arm angular velocity 912. Additionally, the vibration feedback generation unit 45 performs time differentiation on the rotation angle of the motor M detected by the encoder E, i.e., the motor shaft position 902, to obtain the motor shaft angular velocity 913. Next, the vibration feedback generation unit 45 subtracts the motor shaft angular velocity 913 from the motor shaft equivalent arm angular velocity 912 to obtain the vibration angular velocity 914. Finally, the vibration feedback generation unit 45 multiplies the vibration angular velocity 914 by the feedback gain Kgp to obtain the vibration feedback 915.

[0115] The position command generation unit 41 generates a position command 901 for the motor M based on a program created by the host computer. First, the position control unit 42 calculates the position deviation 903 after subtracting the motor shaft position 902 detected by the encoder E from the position command 901. Next, the position control unit 42 multiplies the position deviation 903 by the position cycle proportional gain Kpp to obtain the speed command 904.

[0116] The speed control unit 43 is configured with proportional-integral control. First, the speed control unit 43 adds the speed command 904 to the vibration feedback 915 generated by the vibration feedback generation unit 45 to obtain the speed cycle command 905. Next, the speed control unit 43 obtains the current command 906 by adding the proportional term obtained by multiplying the speed cycle command 905 by the speed cycle proportional gain Kvp to the integral term obtained by multiplying the integral value of the speed cycle command 905 by the speed cycle integral gain Kvi.

[0117] The current control unit 44 controls the motor M in such a way that the current 907 driving the motor M is consistent with the current command 906, that is, the current 907 follows the current command 906. Then, the motor M is driven by the current 907 controlled by the current control unit 44.

[0118] The above text provided an example of control. Next, several examples of the configuration of inertial sensor 3 will be explained. For example, as... Figure 12 As shown, when viewed from a vertical direction, that is, from a direction orthogonal to the central axis A of the third rotation axis J3 and the third arm 223, the inertial sensor 3 is located on the central axis A of the third arm 223. For the robot system 1, the central axis A is orthogonal to the third rotation axis J3 and parallel to the fourth rotation axis J4. In other words, the central axis A is parallel to the direction in which the third and fourth arms extend. With this configuration, it is easy to position the inertial sensor 3. Moreover, the inertial sensor 3 is positioned at the end on the side of the fourth joint 234, that is, the end on the side opposite to the third joint 233. Thus, the inertial sensor 3 can be positioned as far apart from the third rotation axis J3 as possible, and therefore a larger acceleration Azs can be detected. Here, another example of the central axis A of the arm is an axis parallel to the direction in which the arm extends and passes through the center of gravity of the arm. Alternatively, the central axis A of the arm can also be an axis parallel to the line segment connecting the center of gravity of the joint that connects the arm to the front end side to the center of gravity of the joint that connects the arm to the base end side. The inertial sensor 3 is configured to acquire acceleration Azs in a direction orthogonal to the central axis A of the arm, thereby enabling it to accurately detect the acceleration generated by the rotational motion of the arm driven by at least one of the base-side joint and the front-side joint.

[0119] In addition, for example, Figure 13As shown, when a motor M serving as a drive source is arranged within the third arm 223, the inertial sensor 3 is separately configured from the motor M. Therefore, vibrations generated by the drive of the motor M are less likely to be transmitted to the inertial sensor 3, allowing the inertial sensor 3 to accurately detect the angular velocity ωs and acceleration Azs. It should be noted that the motor M arranged within the third arm 223 can be any motor M found in any joint. For example, it could be a motor M found in the third joint 233 or a motor M found in the fourth joint 234.

[0120] In addition, for example, Figure 14 As shown, the inertial sensor 3 is disposed within the third arm 223. This protects the inertial sensor 3 from moisture, dust, and other contaminants. Furthermore, the inertial sensor 3 is disposed on the wall of the third arm 223. Specifically, the third arm 223 has a frame 223a connected to the other arm and a cover 223b fitted to the frame 223a, with the inertial sensor 3 disposed on the wall of the cover 223b. Since the frame 223a houses the reducer and motor M, the placement of the inertial sensor 3 on the cover 223b prevents vibrations generated by the reducer and motor M from being easily transmitted to the inertial sensor 3. Therefore, the angular velocity ωs and acceleration Azs can be detected with high accuracy using the inertial sensor 3.

[0121] In addition, for example, Figure 15 As shown, the wall portion, i.e., the cover 223b, has an inner wall 223c, an outer wall 223d, and a hollow portion 223e located between the inner wall 223c and the outer wall 223d, inertial sensor 3 being disposed in the hollow portion 223e. Thus, by housing the inertial sensor 3 within the cover 223b, it can be protected from moisture, dust, and other contaminants. Furthermore, the inertial sensor 3 is disposed on the outer wall 223d. Consequently, vibrations generated by the reducer and motor M are less likely to be transmitted to the inertial sensor 3. Therefore, angular velocity ωs and acceleration Azs can be detected with high accuracy using the inertial sensor 3.

[0122] In the above, the robot system 1 has been described. Such a robot system 1 has, as described above, the robot 2 provided with the robot arm 22 including the plurality of arms, i.e., the first, second, third, fourth, fifth, and sixth arms 221, 222, 223, 224, 225, 226, and the plurality of joints, i.e., the first, second, third, fourth, fifth, and sixth joints 231, 232, 233, 234, 235, 236, the plurality of joints including the second joint 232 as the base end side joint having the second and third rotation axes J2, J3 as the rotation axes parallel to each other and the third joint 233 as the front end side joint located on the front end side of the second joint 232, and the inertial sensor 3 arranged in the third arm 223 connecting the third joint 233 and the fourth joint 234 located on the front end side of the third joint 233, the inertial sensor 3 detecting the angular velocity ωs around the axis parallel to the second and third rotation axes J2, J3 and the acceleration Azs in the direction orthogonal to the central axis A of the third arm 223 in which the inertial sensor 3 is arranged and orthogonal to the second and third rotation axes J2, J3. According to such a configuration, it is possible to detect the vibration amounts of the respective joints of the second and third joints 232, 233 based on the relationship between the angular velocity ωs and the acceleration Azs detected by the inertial sensor 3. Further, by controlling the vibration based on the vibration amounts of the respective joints, it is possible to effectively reduce the vibration of the robot arm 22. In particular, by arranging the inertial sensor 3 in the third arm 223, it is possible to detect the angular velocity ωs and the acceleration Azs even when the robot arm 22 is in an arbitrary posture.

[0123] In addition, as described above, the robot system 1 has the robot 2 provided with the robot arm 22 including a plurality of arms, i.e., first, second, third, fourth, fifth, and sixth arms 221, 222, 223, 224, 225, 226, and a plurality of joints, i.e., first, second, third, fourth, fifth, and sixth joints 231, 232, 233, 234, 235, 236, the plurality of joints including the second joint 232 as a base end side joint having the second and third rotation axes J2, J3 as rotation axes parallel to each other, and the third joint 233 as a front end side joint located on a front end side of the second joint 232, and the inertial sensor 3 disposed in any one of the arms, i.e., the third, fourth, and fifth arms 223, 224, 225, between the third joint 233 and the sixth joint 236 located on the most front end side, the inertial sensor 3 detecting an angular velocity ωs around an axis parallel to the second and third rotation axes J2, J3 and an acceleration Azs in a direction orthogonal to a central axis A of the arm in which the inertial sensor 3 is disposed and orthogonal to the second and third rotation axes J2, J3. According to such a configuration, it is possible to detect the amounts of vibration of the respective joints of the second and third joints 232, 233 based on the relationship between the angular velocity ωs and the acceleration Azs detected by the inertial sensor 3. Further, by controlling the vibration based on the amounts of vibration of the respective joints, it is possible to effectively reduce the vibration of the robot arm 22. In particular, by disposing the inertial sensor 3 away from the sixth arm 226 located on the most front end side, it is possible to minimize the number of joints between the inertial sensor 3 and the third joint 233. Therefore, the angular velocity ωs and the acceleration Azs are easily detected without being affected by the posture of the robot arm 22.

[0124] In addition, as described above, the robot 2 has the base 21, the robot arm 22 has the first arm 221 connected to the base 21 via a joint different from the base end side joint and the front end side joint, i.e., the first joint 231, the second arm 222 connected to the first arm 221 via the second joint 232 as the base end side joint, and the third arm 223 connected to the second arm 222 via the third joint 233 as the front end side joint. Further, the inertial sensor 3 is disposed in the third arm 223. According to such a configuration, the detection axis of the angular velocity detecting element 31a is maintained in a state parallel to the second and third rotation axes J2, J3 and the detection axis of the acceleration detecting element 32a is maintained in a state orthogonal to the second and third rotation axes J2, J3 at any posture of the robot arm 22, and thus it is possible to more reliably detect the angular velocity ωs and the acceleration Azs.

[0125] In addition, as described above, the inertial sensor 3 is located on the central axis A of the third arm 223 when viewed from a direction orthogonal to the second and third rotation axes J2, J3 and the central axis A of the third arm 223. According to such a configuration, it is easy to dispose the inertial sensor 3.

[0126] In addition, as described above, the inertial sensor 3 is disposed at the end portion of the third arm 223 on the side opposite to the third joint 233. Thereby, the inertial sensor 3 can be disposed as far as possible from the third rotational axis J3, and thus a larger acceleration Azs can be detected.

[0127] In addition, as described above, the robot 2 has a motor M disposed in the third arm 223 and serving as a drive source for driving the robot arm 22. Further, the inertial sensor 3 is disposed separately from the motor M. Thereby, vibrations generated by the driving of the motor M are less likely to be transmitted to the inertial sensor 3, and the angular velocity ωs and the acceleration Azs can be accurately detected by the inertial sensor 3.

[0128] In addition, as described above, the inertial sensor 3 is disposed in the third arm 223. Thereby, the inertial sensor 3 can be protected from moisture, dust, and the like.

[0129] In addition, as described above, the inertial sensor 3 is disposed in the cover 223b serving as a wall portion of the third arm 223. Thereby, vibrations generated from the speed reducer and the motor M are less likely to be transmitted to the inertial sensor 3. Thus, the angular velocity ωs and the acceleration Azs can be accurately detected by the inertial sensor 3.

[0130] In addition, as described above, the cover 223b serving as a wall portion has an inner wall 223c, an outer wall 223d, and a hollow portion 223e between the inner wall 223c and the outer wall 223d. Further, the inertial sensor 3 is disposed in the hollow portion 223e. Thereby, the inertial sensor 3 can be protected from moisture, dust, and the like.

[0131] Second Embodiment

[0132] Figure 16 is a schematic view showing a robot according to the second embodiment. Figure 17 is a view showing the disposition of an inertial sensor.

[0133] The robot system 1 according to the present embodiment is the same as the robot system 1 according to the first embodiment described above except for the configuration and disposition of the inertial sensor 3. Note that, in the following description, the robot system 1 according to the present embodiment is described focusing on the differences from the first embodiment described above, and the description of the same matters is omitted. In addition, in each drawing according to the present embodiment, the same reference numerals are assigned to the same configurations as those according to the first embodiment described above.

[0134] As Figure 16As shown, in the robot system 1 of the present embodiment, the inertia sensor 3 is provided to the fourth arm 224. The inertia sensor 3 detects the acceleration Azs in a direction orthogonal to the central axis of the fourth arm 224 and orthogonal to the second and third turning axes J2, J3. In this way, by providing the inertia sensor 3 to the fourth arm 224, the inertia sensor 3 can be further separated from the second and third turning axes J2, J3, and thus can detect a larger acceleration Azs. Therefore, the amount of vibration of each of the second and third joints 232, 233 can be more accurately determined.

[0135] In such a configuration, the detection axis of the inertia sensor 3 rotates with respect to the second and third turning axes J2, J3 in accordance with the turning of the fourth joint 234. Therefore, in a configuration in which the inertia sensor 3 has one angular velocity detection element 31a and one acceleration detection element 32a as in the first embodiment described above, the angular velocity ωs and the acceleration Azs cannot be detected depending on the orientation of the fourth joint 234.

[0136] Therefore, the inertia sensor 3 of the present embodiment has an angular velocity detection element 31b in addition to the angular velocity detection element 31a, the angular velocity detection element 31b having a detection axis orthogonal to the detection axis of the angular velocity detection element 31a and the fourth turning axis J4. In addition, the inertia sensor 3 of the present embodiment has an acceleration detection element 32b in addition to the acceleration detection element 32a, the acceleration detection element 32b having a detection axis orthogonal to the detection axis of the acceleration detection element 32a and the fourth turning axis J4. That is, the inertia sensor 3 can detect the angular velocity around two axes orthogonal to the fourth turning axis J4 and to each other and the acceleration in the directions of two axes orthogonal to the fourth turning axis J4 and to each other. According to such a configuration, the angular velocity ωs can be detected based on the angular velocities detected by the angular velocity detection elements 31a, 31b and the acceleration Azs can be detected based on the accelerations detected by the acceleration detection elements 32a, 32b regardless of the orientation of the fourth joint 234.

[0137] In addition, as shown, Figure 17 The inertia sensor 3 is provided to the fourth turning axis J4 of the fourth arm 224. Therefore, the positional relationship between the second and third turning axes J2, J3 and the inertia sensor 3 remains constant regardless of the orientation of the fourth arm 224. Therefore, the calculation of the angular velocity ωs and the acceleration Azs is facilitated.

[0138] As described above, the robot system 1 of the present embodiment has the robot 2 provided with the robot arm 22 including a plurality of arms, i.e., first, second, third, fourth, fifth, and sixth arms 221, 222, 223, 224, 225, 226, and a plurality of joints, i.e., first, second, third, fourth, fifth, and sixth joints 231, 232, 233, 234, 235, 236, the plurality of joints including the second joint 232 as a base end side joint having the second and third rotation axes J2, J3 as rotation axes parallel to each other and the third joint 233 as a front end side joint located on a front end side of the second joint 232, and the inertial sensor 3 disposed at the fourth arm 224 connecting the fourth joint 234 located on a front one front end side of the third joint 233 and the fifth joint 235 located on a front one front end side of the fourth joint 234, the inertial sensor 3 detecting the angular velocity ωs around an axis parallel to the second and third rotation axes J2, J3 and the acceleration Azs in a direction orthogonal to the central axis of the fourth arm 224 in which the inertial sensor 3 is disposed and orthogonal to the second and third rotation axes J2, J3. According to such a configuration, it is possible to detect the vibration amounts of the respective joints of the second and third joints 232, 233 based on the relationship between the angular velocity ωs and the acceleration Azs detected by the inertial sensor 3. Further, by controlling the vibration based on the vibration amounts of the respective joints, it is possible to effectively reduce the vibration of the robot arm 22. In particular, by disposing the inertial sensor 3 at the fourth arm 224, it is possible to further separate the disposition of the inertial sensor 3 from the second and third rotation axes J2, J3, and thus it is possible to detect a larger acceleration Azs. Therefore, it is possible to more accurately determine the vibration amounts of the respective joints of the second and third joints 232, 233.

[0139] In addition, as described above, the robot 2 has the base 21, and the robot arm 22 has the first arm 221 connected to the base 21 via the first joint 231 which is different from the base end side joint and different from the front end side joint, the second arm 222 connected to the first arm 221 via the second joint 232 which is the base end side joint, the third arm 223 connected to the second arm 222 via the third joint 233 which is the front end side joint, and the fourth arm 224 connected to the third arm 223 via the fourth joint 234 which is different from the base end side joint and different from the front end side joint. Further, the inertial sensor 3 which detects the angular velocity around two axes orthogonal to the fourth rotational axis J4 and to each other and the acceleration in the direction of two axes orthogonal to the fourth rotational axis J4 and to each other is provided to the fourth arm 224. According to such a configuration, the angular velocity ωs and the acceleration Azs can be detected regardless of the orientation of the fourth joint 234. In addition, the inertial sensor 3 can be provided separately from the second and third rotational axes J2 and J3, and thus a larger acceleration Azs can be detected. Therefore, the amount of vibration of each of the second and third joints 232 and 233 can be determined with higher accuracy and better precision.

[0140] In addition, as described above, the inertial sensor 3 is located on the fourth rotational axis J4 which is the rotational axis of the fourth arm 224. Therefore, the positional relationship between the second and third rotational axes J2 and J3 and the inertial sensor 3 remains constant regardless of the orientation of the fourth arm 224. Thus, the calculation of the angular velocity ωs and the acceleration Azs is facilitated.

[0141] The same effects as those of the first embodiment described above can also be achieved by the second embodiment.

[0142] Third Embodiment

[0143] Figure 18 is a schematic view showing a robot according to the third embodiment.

[0144] The robot system 1 according to the present embodiment is the same as the robot system 1 according to the first embodiment described above except for the configuration of the inertial sensor 3. Note that, in the following description, the robot system 1 according to the present embodiment is described focusing on the differences from the first embodiment described above, and the description of the same matters is omitted. In addition, in the drawings of the present embodiment, the same reference numerals are assigned to the same configurations as those of the first embodiment described above.

[0145] For example, in a posture in which the second and third arms 222 and 223 are orthogonal as shown in Figure 9 In this posture, the acceleration Azs generated by the vibration of the second joint 232 is small, and the translational velocity Vzs is also small. Therefore, it can be difficult to determine the amount of vibration of each of the second and third joints 232 and 233 with high accuracy.

[0146] Therefore, as Figure 18 As shown, the inertial sensor 3 of this embodiment includes an acceleration detection element 32b in addition to the acceleration detection element 32a. The acceleration detection element 32b has a detection axis orthogonal to the detection axis of the acceleration detection element 32a and the second and third rotation axes J2 and J3. With this configuration, the detection axis of the acceleration detection element 32a is approximately aligned with the direction of the acceleration generated by the vibration of the second joint 232, allowing the acceleration detection element 32b to detect larger accelerations. Therefore, the vibration amount of each joint of the second joint 232 and the third joint 233 can be determined with high accuracy.

[0147] It should be noted that, in Figure 18 In the middle, the vertical translational velocity Vzs of inertial sensor 3 is Vzs=L2×ω2+√(L3) 2 +Lsz 2 The horizontal translational velocity Vxs is represented by Vxs = L2 × ω2. Therefore, the following equation (7) holds. Furthermore, the vibration of the second joint 232 and the third joint 233 can be determined based on the values ​​of angular velocities ω2 and ω3 obtained from equation (7).

[0148] [Formula 7]

[0149]

[0150] This third implementation method can achieve the same effect as the first implementation method described above.

[0151] Fourth Implementation Method

[0152] Figure 19 This is a schematic diagram illustrating the robot according to the fourth embodiment.

[0153] The robot system 1 described in this embodiment is identical to the robot system 1 described in the first embodiment, except for the configuration of the inertial sensor 3. It should be noted that in the following description, the robot system 1 of this embodiment will be described primarily for its differences from the first embodiment, and descriptions of identical components will be omitted. Furthermore, in the accompanying drawings of this embodiment, components identical to those in the previous embodiment will be given the same reference numerals.

[0154] In the robot system 1 of this embodiment, the inertial sensor 3 is configured to detect vibrations about the first rotation axis J1 of the first joint 231. Specifically, as Figure 19As shown, the inertial sensor 3 of this embodiment, in addition to the angular velocity detection element 31a, also includes angular velocity detection elements 31c and 31d. These angular velocity detection elements 31c and 31d have detection axes orthogonal to and mutually orthogonal to the detection axis of the angular velocity detection element 31a. With this configuration, regardless of the orientation of the second and third joints 232 and 233, the vibration of the first rotation axis J1 around the first joint 231 can be detected based on the angular velocity detected by the angular velocity detection elements 31c and 31d. It should be noted that, for ease of explanation, the acceleration detection element 32a is not shown in the diagram.

[0155] This fourth implementation method can also achieve the same effect as the first implementation method described above.

[0156] Fifth Implementation Method

[0157] Figure 20 This is a schematic diagram illustrating the robot according to the fifth embodiment.

[0158] The robot system 1 described in this embodiment is identical to the robot system 1 described in the first embodiment, except for the configuration of the robot 2 and the configuration of its corresponding inertial sensor 3. It should be noted that in the following description, the robot system 1 of this embodiment will be described primarily for its differences from the first embodiment, and descriptions of identical items will be omitted. Furthermore, in the accompanying drawings of this embodiment, the same reference numerals are used for components identical to those in the previous embodiment.

[0159] like Figure 20 As shown, the robot 2 in this embodiment is a seven-axis vertical multi-joint robot with seven drive axes. Furthermore, the robotic arm 22 is configured such that the first, second, third, fourth, fifth, sixth, and seventh arms 221, 222, 223, 224, 225, 226, and 227 are connected via the first, second, third, fourth, fifth, sixth, and seventh joints 231, 232, 233, 234, 235, 236, and 237.

[0160] Specifically, the first arm 221 is connected to the base 21 via the first joint 231 so as to be rotatable about the first rotation axis Jl. In addition, the second arm 222 is connected to the first arm 221 via the second joint 232 so as to be rotatable about the second rotation axis J2. In addition, the third arm 223 is connected to the second arm 222 via the third joint 233 so as to be rotatable about the third rotation axis J3. In addition, the fourth arm 224 is connected to the third arm 223 via the fourth joint 234 so as to be rotatable about the fourth rotation axis J4. In addition, the fifth arm 225 is connected to the fourth arm 224 via the fifth joint 235 so as to be rotatable about the fifth rotation axis J5. In addition, the sixth arm 226 is connected to the fifth arm 225 via the sixth joint 236 so as to be rotatable about the sixth rotation axis J6. In addition, the seventh arm 227 is connected to the sixth arm 226 via the seventh joint 237 so as to be rotatable about the seventh rotation axis J7.

[0161] In addition, the second, fourth, and sixth joints 232, 234, 236 among the first, second, third, fourth, fifth, sixth, and seventh joints 231, 232, 233, 234, 235, 236, 237 are respectively bend joints, and the first, third, fifth, and seventh joints 231, 233, 235, 237 are respectively twist joints. In addition, the second rotation axis J2 is orthogonal to the first rotation axis Jl, the third rotation axis J3 is orthogonal to the second rotation axis J2, the fourth rotation axis J4 is orthogonal to the third rotation axis J3, the fifth rotation axis J5 is orthogonal to the fourth rotation axis J4, the sixth rotation axis J6 is orthogonal to the fifth rotation axis J5, and the seventh rotation axis J7 is orthogonal to the sixth rotation axis J6.

[0162] In addition, the third arm 223 is provided with an inertial sensor 3. The inertial sensor 3 is capable of detecting an angular velocity ωs about an axis parallel to the third rotation axis J3 and an acceleration Axs in a direction orthogonal to the third rotation axis J3.

[0163] In such a robot 2, the first joint 231 is the "base end side joint" of the present application, and the third joint 233 is the "front end side joint" of the present application. That is, in the robot 2, the second joint 232 is located between the base end side joint and the front end side joint. In the robot 2, as shown in FIG. 2, the second joint 232 is parallel to the first rotation axis Jl of the first joint 231 as the base end side joint and the third rotation axis J3 of the third joint 233 as the front end side joint at a predetermined orientation. Therefore, the vibration amount of each joint of the first joint 231 and the third joint 233 can be detected by the same method as in the first embodiment described above. Figure 20

[0164] ​As described above, the robot 2 of the present embodiment has the base 21. In addition, the robot arm 22 has a first arm 221 connected to the base 21 via a first joint 231 as a base end side joint, a second arm 222 connected to the first arm 221 via a second joint 232 as a joint different from the base end side joint and different from the front end side joint, and a third arm 223 connected to the second arm 222 via a third joint 233 as a front end side joint. Further, the inertial sensor 3 is arranged in the third arm 223. According to such a configuration, when the second joint 232 is in a predetermined orientation, the first rotation axis Jl of the first joint 231 as the base end side joint and the third rotation axis J3 of the third joint 233 as the front end side joint are parallel, and the vibration amount of each of the first and third joints 231, 233 can be detected.

[0165] With the fifth embodiment as well, the same effects as those of the first embodiment described above can be obtained.

[0166] Sixth Embodiment

[0167] Figure 21 is a view showing a robot according to the sixth embodiment.

[0168] The robot system 1 according to the present embodiment is the same as the robot system 1 of the first embodiment described above except for the configuration of the robot 5 and the arrangement of the inertial sensor 3 corresponding thereto. Note that in the following description, the robot system 1 of the present embodiment is described focusing on the differences from the first embodiment described above, and the description of the same matters is omitted. In addition, in the drawings of the present embodiment, the same reference numerals are given to the same configurations as those of the first embodiment described above.

[0169] As shown in Figure 21 , the robot 5 of the present embodiment is a horizontal multi-joint robot (SCARA robot). Such a robot 5 has a base 51 and a robot arm 52 connected to the base 51. In addition, the robot arm 52 is configured such that first and second arms 521, 522 are connected via first and second joints 541, 542.

[0170] The first arm 521 is connected to the base 21 via the first joint 541 so as to be rotatable about a first rotation axis Jl 1. In addition, the second arm 522 is connected to the first arm 521 via the second joint 542 so as to be rotatable about a second rotation axis Jl 2. In addition, these first and second joints 541, 542 are torsion joints, and the first and second rotation axes Jl 1, Jl 2 are parallel and along the vertical direction with respect to each other.

[0171] Additionally, a working head 53 is provided at the front end of the second arm 522. The working head 53 includes a spline nut 531 and a ball screw nut 532 coaxially arranged at the front end of the second arm 522, and a spline shaft 533 serving as the main shaft inserted into the spline nut 531 and the ball screw nut 532. The spline shaft 533 is its central axis relative to the second arm 522 and can rotate about a third rotation axis J13 along the vertical direction and can move (lift / lower) along the third rotation axis J13. Furthermore, an assembly part 533 for mounting an end effector (not shown) is provided at the lower end of the spline shaft 533. The end effector can be easily installed and removed from the assembly part 533a, and can be appropriately selected to suit the target operation. It should be noted that the third rotation axis J13 is along the vertical direction and parallel to the first and second rotation axes J11 and J12.

[0172] In such a robot 5, the first joint 541 is the "base end joint" of this application, and the second joint 542 is the "front end joint" of this application.

[0173] In addition, each joint 541, 542 includes: a motor M, a speed reducer (not shown) that reduces the rotational speed of the motor M and outputs a speed reducer, and an encoder E that detects the amount of rotation of the motor M.

[0174] In addition, such as Figure 21 As shown, the inertial sensor 3 is disposed in the second arm 522. In addition, the inertial sensor 3 has: an angular velocity detection element 31a, which detects the angular velocity ωs about an axis with the same orientation as the first and second rotation axes J11 and J12; and an acceleration detection element 32a, which detects the acceleration Axs in a direction orthogonal to the first and second rotation axes J11 and J12.

[0175] In the robot system 1 configured in this way, the vibration amount of each joint of the first joint 541 and the second joint 542 can also be detected by the same method as described in the first embodiment.

[0176] This sixth implementation method can also achieve the same effect as the first implementation method described above.

[0177] The robot control method and robot system of this utility model have been described above through the illustrated embodiments. However, this utility model is not limited thereto, and the composition and process of each part can be replaced with any composition and process having the same function. In addition, other arbitrary compositions and processes can be added to this utility model. Furthermore, the various embodiments can be appropriately combined.

Claims

1. A robotic system, characterized by, Having: a robot provided with a robot arm including a plurality of arms and a plurality of joints including a base end side joint having rotation axes parallel to each other and a front end side joint located on a front end side of the base end side joint; and an inertial sensor disposed on the arm connecting the front end side joint and the joint located on a front one front end side of the front end side joint, the inertial sensor detects an angular velocity around an axis parallel to the rotation axes and an acceleration in a direction orthogonal to a central axis of the arm in which the inertial sensor is disposed and orthogonal to the rotation axes, the robot has a base, the robot arm has a first arm connected to the base via the joint different from the base end side joint and the front end side joint, a second arm connected to the first arm via the base end side joint, and a third arm connected to the second arm via the front end side joint, the inertial sensor is disposed on the third arm.

2. A robot system, characterized in that Having: a robot provided with a robot arm including a plurality of arms and a plurality of joints including a base end side joint having rotation axes parallel to each other and a front end side joint located on a front end side of the base end side joint; and an inertial sensor disposed on the arm connecting the joint located on a front one front end side of the front end side joint and the joint located on a further front one front end side, the inertial sensor detects an angular velocity around an axis parallel to the rotation axes and an acceleration in a direction orthogonal to a central axis of the arm in which the inertial sensor is disposed and orthogonal to the rotation axes, the robot has a base, the robot arm has a first arm connected to the base via the base end side joint, a second arm connected to the first arm via the joint different from the base end side joint and the front end side joint, and a third arm connected to the second arm via the front end side joint, the inertial sensor is disposed on the third arm.

3. A robot system, characterized by Having: a robot provided with a robot arm including a plurality of arms and a plurality of joints including a base end side joint having rotation axes parallel to each other and a front end side joint located on a front end side of the base end side joint; and an inertial sensor disposed on the arm between the front end side joint and the joint located on a most front end side, the inertial sensor detects an angular velocity around an axis parallel to the rotation axes and an acceleration in a direction orthogonal to a central axis of the arm in which the inertial sensor is disposed and orthogonal to the rotation axes, the robot has a base, the robot arm has a first arm connected to the base via the joint different from the base end side joint and the front end side joint, a second arm connected to the first arm via the base end side joint, and a third arm connected to the second arm via the front end side joint, the inertial sensor is disposed on the third arm.

4. The robot system according to claim 1 or 3, characterized in that, The inertial sensor is located on the central axis of the third arm when viewed from a direction orthogonal to the central axis of the third arm and the rotation axis.

5. The robot system according to claim 1 or 3, wherein The inertial sensor is disposed at an end portion of the third arm on a side opposite to the front end side joint.

6. The robot system according to claim 1 or 3, wherein The robot has a drive source disposed in the third arm and driving the robot arm, The inertial sensor is disposed separately from the drive source.

7. The robot system according to claim 1 or 3, wherein The inertial sensor is disposed in the third arm.

8. The robot system according to claim 7, wherein The inertial sensor is disposed in a wall portion of the third arm.

9. The robot system according to claim 7, wherein The wall portion has an inner wall, an outer wall, and a hollow portion between the inner wall and the outer wall, The inertial sensor is disposed in the hollow portion.

10. A robot system, characterized by A robot has a robot arm including a plurality of arms and a plurality of joints, the plurality of joints including a base end side joint having rotation axes parallel to each other and a front end side joint located on a front end side of the base end side joint, and an inertial sensor disposed in an arm connecting a joint located one front end side of the front end side joint and a joint located one more front end side. The inertial sensor detects angular velocity around axes parallel to the rotation axes and acceleration in directions orthogonal to a central axis of the arm in which the inertial sensor is disposed and orthogonal to the rotation axes. The robot has a base, The robot arm has a first arm connected to the base via a joint different from the base end side joint and different from the front end side joint, a second arm connected to the first arm via the base end side joint, a third arm connected to the second arm via the front end side joint, and a fourth arm connected to the third arm via a joint different from the base end side joint and different from the front end side joint. The inertial sensor is disposed in the fourth arm. The inertial sensor detects angular velocity around two axes orthogonal to the rotation axes of the fourth arm and orthogonal to each other and acceleration in directions of the two axes orthogonal to the rotation axes of the fourth arm and orthogonal to each other.

11. The robot system according to claim 10, wherein The inertial sensor is located on the rotation axes of the fourth arm. ​ ​ ​

Images