JPWO2016185600A1 - Robot controller - Google Patents

Abstract

The robot control device that controls the actuator 2 that drives the robot joint includes a vibration frequency storage unit (6) that outputs the stored vibration frequency, and a vibration signal generation unit (7) that receives the vibration frequency and outputs a vibration signal. ) And a corrected position command in which a vibration signal is added to the position command, and a control command for controlling the position of the actuator (2), a joint angle that is a joint angle, and an actual driving torque of the actuator (2). A position control unit (1) for outputting a drive torque, a drive torque estimation unit (3) for receiving a joint angle as an input and outputting a drive torque estimation value necessary for driving the actuator (2), and a drive torque estimation value A disturbance torque calculation unit (4) that receives a difference between the drive torque estimated value and the actual drive torque as a first disturbance torque estimated value, and a first disturbance As input torque estimation value, and a vibration component removing unit (5) the frequency components of the vibration frequency from the first disturbance torque estimation value to output a second disturbance torque estimation value that has been removed.

Description

  The present invention relates to a robot control apparatus that drives a robot using an actuator.

  In the master-slave robot that directly controls the robot according to the guidance of the worker or transmits the external force acting on the master robot to the slave robot, the external force acting on the robot is estimated and based on the estimated external force It is necessary to control. Therefore, it is conceivable to attach a force sensor to the tip of the robot. When a force sensor is attached to the tip of the robot, the external force can be measured with high accuracy, but the force sensor itself is expensive and has a problem that it is vulnerable to impacts. Often. Therefore, a method for estimating an external force acting on a robot using a position and torque obtained from an actuator without using a force sensor has been proposed.

  Patent Document 1, which is an example of such a technique, uses a mathematical model of friction hysteresis characteristics and a history of torque input and disturbance torque estimated values for the purpose of reducing the torque estimation error when the drive shaft is stationary. Thus, a technique for compensating the hysteresis characteristic of friction is disclosed.

Japanese Patent Laid-Open No. 10-264057

  However, according to the technique disclosed in Patent Document 1 which is the conventional technique, a mathematical model of the hysteresis characteristic of friction is used. This mathematical model is a friction model including a maximum static friction force and a Coulomb friction force. Requires parameters. Therefore, if the actual friction characteristics are different from the mathematical model, or if the friction parameters change due to changes in the ambient temperature and aging of the robot, the disturbance torque acting on the robot cannot be estimated with high accuracy. was there.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a robot control apparatus capable of estimating a disturbance torque acting on a robot with high accuracy.

  In order to solve the above-described problems and achieve the object, the present invention is a robot control apparatus that controls an actuator that drives a joint of a robot, and includes a vibration frequency storage unit that outputs a stored vibration frequency; A vibration signal generator that outputs a vibration signal with a vibration frequency as an input, and a corrected position command obtained by adding the vibration signal to a position command, and a control command that controls the position of the actuator, the angle of the joint A position control unit that outputs a certain joint angle and an actual driving torque that is a driving torque of the actuator; and a driving torque estimation unit that receives the joint angle and outputs a driving torque estimation value required to drive the actuator; The drive torque estimated value and the actual drive torque are input, and the difference between the drive torque estimated value and the actual drive torque is calculated as a first disturbance torque. A disturbance torque calculation unit that outputs the estimated disturbance value and the second disturbance torque estimated value obtained by removing the frequency component of the vibration frequency from the first disturbance torque estimated value. And a vibration component removing unit that outputs the signal.

  According to the present invention, there is an effect that it is possible to obtain a robot control device capable of estimating a disturbance torque acting on a robot with high accuracy.

1 is a block diagram showing a configuration example of a robot control device according to a first embodiment and an actuator to which a control command is input from the robot control device. Block diagram showing a configuration example of a drive torque estimation unit Block diagram showing one configuration example of the vibration component removing unit Block diagram showing a configuration example of the position command generator Block diagram showing one configuration example of the first axis impedance model Block diagram showing a comparative example of a robot controller that performs impedance control based on an estimated value of disturbance torque FIG. 3 is a block diagram showing a configuration example of a robot control device according to a second embodiment and an actuator to which a control command is input from the robot control device. Block diagram showing one configuration example of the vibration signal generator FIG. 3 is a block diagram showing a configuration example of a robot control device according to a third embodiment and an actuator to which a control command is input from the robot control device. Block diagram showing a configuration example of the position command generator FIG. 6 is a block diagram showing a configuration example of a robot control device according to a fourth embodiment and an actuator to which a control command is input from the robot control device.

  Hereinafter, a robot control apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a block diagram illustrating a configuration example of the robot control apparatus according to the first embodiment of the present invention and an actuator to which a control command is input from the robot control apparatus. The robot control apparatus shown in FIG. 1 is a robot control apparatus that controls an actuator 2 that drives a joint of a robot, and a vibration frequency storage unit 6 that outputs a stored vibration frequency and the vibration frequency as an input. The vibration signal generator 7 that outputs a signal, and a corrected position command obtained by adding the vibration signal to the position command are input, and a control command for controlling the position of the actuator 2, the joint angle that is the angle of the joint, and the actuator 2 A position control unit 1 that outputs an actual driving torque that is a driving torque of the motor, a driving torque estimating unit 3 that outputs the driving torque estimation value that is necessary to drive the actuator 2 using the joint angle as an input, and a driving torque estimation A disturbance torque that outputs the difference between the drive torque estimated value and the actual drive torque as the first disturbance torque estimated value. And a vibration component removing unit 5 that receives the first disturbance torque estimated value and outputs a second disturbance torque estimated value obtained by removing the frequency component of the vibration frequency from the first disturbance torque estimated value. .

  The position control unit 1 receives a corrected position command and receives a control command for controlling the position of the actuator 2 installed at each joint of the robot, a joint angle that is an angle of each joint of the robot, and a driving torque of the actuator 2. The actual driving torque is output.

  The drive torque estimation unit 3 receives the joint angle output from the position control unit 1, estimates the drive torque necessary to drive the robot, calculates the drive torque estimated value, and outputs it.

  FIG. 2 is a block diagram illustrating a configuration example of the drive torque estimation unit. The drive torque estimation unit 3 illustrated in FIG. 2 includes a gravity torque calculation unit 31, a joint angular velocity calculation unit 32, a friction torque calculation unit 33, and an addition unit 34. The gravitational torque calculator 31 calculates and outputs an estimated gravitational torque value of each joint of the robot from the input joint angle. The joint angular velocity calculation unit 32 calculates and outputs a joint angular velocity by differentiating or calculating a difference between the input joint angles. The friction torque calculator 33 calculates and outputs an estimated friction torque value based on the joint angular velocity output from the joint angular velocity calculator 32, the preset Coulomb friction torque of the robot, and the viscous friction torque coefficient. The adding unit 34 receives the estimated gravitational torque value output from the gravitational torque calculating unit 31 and the estimated friction torque value output from the friction torque calculating unit 33, and adds these values to obtain an estimated driving torque value. Is calculated and output.

  The drive torque estimating unit 3 shown in FIG. 2 calculates the drive torque estimated value only from the gravity torque estimated value and the friction torque estimated value, but the present invention is not limited to this. The drive torque estimation unit 3 may be configured to further add estimated values of centrifugal Coriolis torque and inertia torque determined from the motion equation of the robot to the drive torque estimated value.

  The disturbance torque calculation unit 4 calculates a difference between the drive torque estimation value output from the drive torque estimation unit 3 and the actual drive torque output from the position control unit 1, and outputs a first disturbance torque estimation value. .

  The vibration frequency storage unit 6 stores and outputs the vibration frequency.

  The vibration component removing unit 5 receives the first disturbance torque estimated value output from the disturbance torque calculating unit 4 and the vibration frequency output from the vibration frequency storage unit 6, and vibrates from the first disturbance torque estimated value. The frequency component of the frequency is removed, and the second disturbance torque estimated value is output.

  FIG. 3 is a block diagram illustrating a configuration example of the vibration component removing unit. The vibration component removing unit 5 illustrated in FIG. 3 includes a vibration frequency notch filter 51, a triple frequency notch filter 52, and a low pass filter 53. The vibration frequency notch filter 51 is a filter that selectively removes the frequency component of the vibration frequency. The triple frequency notch filter 52 is a filter that selectively removes a frequency component that is three times the vibration frequency. The low-pass filter 53 is a filter that removes a frequency component equal to or higher than a preset cutoff frequency. The vibration component removal unit 5 shown in FIG. 3 can efficiently remove the frequency component of the vibration frequency and its harmonic component from the first disturbance torque estimated value. That is, the vibration component of torque caused by friction can be efficiently removed.

  Note that the vibration component removing unit 5 shown in FIG. 3 includes a notch filter having a vibration frequency and a notch filter having a frequency three times that of the vibration frequency, but the present invention is not limited to this. The vibration component removing unit 5 may include a filter that selectively removes a frequency component that is five times or seven times the vibration frequency, and may further include a notch filter that removes higher-order harmonic components.

  The position command generator 9 shown in FIG. 1 receives the second disturbance torque estimated value, calculates a position command, and outputs it. FIG. 4 is a block diagram illustrating a configuration example of the position command generation unit. The position command generator 9 shown in FIG. 4 includes a first axis impedance model 91, a second axis impedance model 92, a third axis impedance model 93, a fourth axis impedance model 94, and a fifth axis impedance model 95. , A sixth axis impedance model 96, a demultiplexer 97, and a multiplexer 98. The demultiplexer 97 decomposes the second disturbance torque estimated value into the component signal of each axis, and outputs the disturbance torque estimated value of each axis from the first axis to the sixth axis. The multiplexer 98 combines the output of the impedance model of each axis from the first axis to the sixth axis into one signal and outputs a position command.

  FIG. 5 is a block diagram illustrating a configuration example of the first axis impedance model. Although FIG. 5 shows the first axis impedance model 91, the second axis impedance model 92, the third axis impedance model 93, the fourth axis impedance model 94, the fifth axis impedance model 95, and the sixth axis impedance model are shown. The configuration of the model 96 is the same.

  A first axis impedance model 91 shown in FIG. 5 includes a dead zone 901, a subtraction unit 902, a model inertia storage unit 903, a division unit 904, a speed integrator 905, a frictional force calculation unit 906, and a position integrator 907. With. The first axis impedance model 91 calculates a speed command for the first axis disturbance torque estimated value according to the impedance characteristics determined by the dead zone 901, the model inertia storage unit 903, and the frictional force calculation unit 906, and the position integrator 907 Takes the speed command as input and calculates and outputs the first axis position command. If the upper limit and the lower limit are set in the range of integration values of the speed integrator 905 and the position integrator 907, it is possible to limit the position and speed range of the impedance model.

  The position command generator 9 having the impedance model shown in FIG. 5 can perform impedance control using the second disturbance torque estimated value. In this way, the second disturbance torque estimated value estimated with high accuracy is used as an input, and impedance control based on predetermined inertia and friction characteristics is performed, so that good impedance characteristics can be obtained regardless of the friction torque of the robot. Can be realized. Here, the impedance control is a method of controlling by setting a mechanical impedance generated when an external force is applied to the robot to a value according to the purpose.

  The vibration signal generation unit 7 outputs a signal calculated for each joint of the robot from the sine wave of the vibration frequency output from the vibration frequency storage unit 6 as a vibration signal. As an example, the amplitude of the vibration signal at the hand position of the robot is sufficiently small so that the vibration amplitude at the hand position of the robot due to the vibration of each joint of the robot is sufficiently small. It is set in advance. The amplitude of the vibration signal can be set to a different value for each joint of the robot.

  The adder 8 adds the position command output from the position command generator 9 and the vibration signal output from the vibration signal generator 7 and outputs a corrected position command.

  Next, the operation of the robot control apparatus according to the first embodiment will be described. FIG. 6 is a block diagram illustrating a comparative example of a robot control apparatus that performs impedance control based on an estimated value of disturbance torque. In FIG. 6, components having functions equivalent to those of the robot control device shown in FIG.

  The robot control device shown in FIG. 6 has a configuration obtained by removing the vibration component removal unit 5, the vibration frequency storage unit 6, the vibration signal generation unit 7, and the addition unit 8 from the robot control device shown in FIG. . In the robot control apparatus shown in FIG. 6, the disturbance torque calculation unit 4 calculates the difference between the drive torque estimated value and the actual drive torque and outputs the disturbance torque estimated value, and the position command generating unit 9 based on the disturbance torque estimated value. Impedance control can be realized by calculating the position command at.

  However, when the robot is stationary, the magnitude of the static friction torque is indefinite, so that the static friction torque and the disturbance torque acting on the robot cannot be estimated separately. For this reason, the robot control apparatus shown in FIG. 6 has a problem that when the robot is stationary, the disturbance torque acting on the robot cannot be accurately estimated, and good impedance characteristics cannot be obtained.

  On the other hand, in the robot control device shown in FIG. 1, the position of the actuator 2 is controlled by a corrected position command obtained by adding the vibration signal generated by the vibration signal generation unit 7 to the position command, so that minute vibration is generated in each joint of the robot. Therefore, each joint of the robot is driven at the vibration frequency of the vibration signal, and a friction torque having the same frequency as the vibration frequency of the vibration signal is generated at each joint of the robot. Furthermore, in the robot control apparatus shown in FIG. 1, the vibration component removing unit 5 removes the vibration component of the frequency of the vibration signal from the first disturbance torque estimated value, so that the first disturbance torque estimated value is changed to the friction torque. The resulting vibration component of the torque can be removed, and the second disturbance torque estimated value output from the vibration component removing unit 5 is the disturbance torque estimated value from which the friction torque has been removed. Therefore, by using the second disturbance torque estimated value as the disturbance torque estimated value, a disturbance torque estimated value from which the influence of the friction torque is removed can be obtained.

  As described above, the robot control apparatus described in the present embodiment can remove the influence of the static friction torque from the estimated disturbance torque value by combining the vibration signal generation unit 7 and the vibration component removal unit 5. it can. Therefore, a disturbance torque having a magnitude smaller than the friction torque can be estimated with high accuracy. Also, by performing impedance control with a highly accurate estimated value of disturbance torque, it is possible to obtain good impedance characteristics without being affected by the friction of the robot. Therefore, the robot control apparatus described in the present embodiment is useful in applications in which the robot is controlled according to the force acting on the robot as in direct teaching.

  The robot control apparatus according to the present embodiment assumes a six-axis robot, but the present invention is not limited to this. By changing the number of axes of the position command generation unit 9, it can be applied to a robot having a different number of axes such as a horizontal articulated robot.

Embodiment 2. FIG.
FIG. 7 is a block diagram illustrating a configuration example of the robot control apparatus according to the second embodiment of the present invention and an actuator to which a control command is input from the robot control apparatus. In FIG. 7, components having functions equivalent to those of the robot control device shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. The robot control device shown in FIG. 7 is different from the robot control device shown in FIG. 1 in that a vibration signal generation unit 7 a is provided instead of the vibration signal generation unit 7.

  The vibration signal generation unit 7a receives the vibration frequency output from the vibration frequency storage unit 6 and the joint angle output from the position control unit 1, and generates and outputs a vibration signal. The vibration signal generation unit 7a is different from the vibration signal generation unit 7 in FIG. 1 in that not only the vibration frequency but also the joint angle is input.

  FIG. 8 is a block diagram illustrating a configuration example of the vibration signal generation unit. The vibration signal generation unit 7a illustrated in FIG. 8 includes a joint angular velocity calculation unit 71, an absolute value calculation unit 72, a joint angular velocity threshold determination unit 73, and a vibration signal calculation unit 74. The joint angular velocity calculation unit 71 calculates a joint angular velocity by differentiating or calculating a difference between the input joint angles. The absolute value calculator 72 calculates and outputs the absolute value of the joint angular velocity output from the joint angular velocity calculator 71. The joint angular velocity threshold value determination unit 73 receives the absolute value of the joint angular velocity output from the absolute value calculation unit 72 as an input, and the joint angular velocity threshold value set in advance for each axis component of the absolute value of the joint angular velocity. The joint angular velocity comparison signal is output. At this time, if the absolute value of the joint angular velocity is equal to or smaller than the joint angular velocity threshold, a true value is output, and if the absolute value of the joint angular velocity is larger than the joint angular velocity threshold, a false value is output. This joint angular velocity threshold is set in advance to a value that allows the robot to be regarded as stationary when the absolute value of the joint angular velocity is equal to or less than the joint angular velocity threshold. The joint angular velocity threshold value can be set to a different value for each joint of the robot.

  The vibration signal calculation unit 74 outputs a vibration signal based on the vibration frequency, the joint angular velocity comparison signal output from the joint angular velocity threshold determination unit 73, and a preset vibration amplitude. At this time, if the component of the relevant axis of the joint angular velocity comparison signal is a true value, a sine wave signal of the vibration frequency is output as the vibration signal of the relevant axis, and if it is a false value, 0 is added to the vibration signal of the relevant axis. Is output. The amplitude of the vibration signal is, for example, such that the vibration amplitude of the robot hand position is within 0.1 mm so that the vibration amplitude of the robot hand position due to the vibration of each joint of the robot is sufficiently small. Are set in advance. The amplitude of the vibration signal can be set to a different value for each joint of the robot.

  When the vibration signal generation unit 7a shown in FIG. 8 determines that the absolute value of the joint angular velocity of the relevant axis of the robot is equal to or less than the joint angular velocity threshold value and the relevant axis of the robot can be regarded as stationary, the vibration of the relevant axis A sine wave signal is output as the signal. On the other hand, when the corresponding axis of the robot is not stationary, 0 is output as the vibration signal of the corresponding axis.

  Next, the operation of the robot control apparatus according to the second embodiment will be described. The vibration signal generator 7a outputs a sine wave signal as a vibration signal when the robot is stationary, and outputs 0 as a vibration signal when the robot is not stationary.

  When the robot is stationary, the position control of the robot is performed by a corrected position command obtained by adding the sine wave signal output from the vibration signal generation unit 7a to the position command, and therefore the same frequency as the vibration frequency of the vibration signal. The friction torque is generated at each joint of the robot. Furthermore, the vibration frequency component included in the first disturbance torque estimated value is removed by the vibration component removing unit 5. Therefore, similarly to the robot control apparatus of the first embodiment, a highly accurate disturbance torque estimated value can be obtained by removing the influence of the friction torque.

  On the other hand, when the robot is not stationary, the friction torque generated at the joint of the robot is uniquely determined according to the joint angular velocity. Therefore, the friction torque estimated value output from the friction torque calculator 33 is used to calculate the friction torque. By performing the compensation, the influence of the friction torque can be removed from the first disturbance torque estimated value. Therefore, when the robot is not stationary, it is possible to calculate the estimated disturbance torque with high accuracy without adding a vibration signal to the position command.

  As described above, the robot control apparatus according to the present embodiment can estimate the disturbance torque with high accuracy by removing the influence of the friction torque from the disturbance torque acting on the robot. Also, by performing impedance control with a highly accurate estimated value of disturbance torque, it is possible to obtain good impedance characteristics without being affected by the friction of the robot. Therefore, the robot control apparatus described in the present embodiment is useful in applications in which the robot is controlled according to the force acting on the robot as in direct teaching.

  Note that the robot control apparatus of the present embodiment stops the vibration of the robot by setting the vibration signal to 0 when the robot is not stationary, so compared with the robot control apparatus of the first embodiment, It is possible to improve the accuracy of position control.

Embodiment 3 FIG.
FIG. 9 is a block diagram illustrating a configuration example of the robot control apparatus according to the third embodiment of the present invention and an actuator to which a control command is input from the robot control apparatus. 9, components having the same functions as those of the robot controller shown in FIGS. 1 and 7 are denoted by the same reference numerals, and description thereof is omitted. The robot control apparatus shown in FIG. 9 is different from the robot control apparatus shown in FIG. 7 in that a position command generation unit 9a is provided instead of the position command generation unit 9. The position command generator 9a shown in FIG. 9 receives the second disturbance torque estimated value and the joint angle as inputs, and outputs a position command.

  FIG. 10 is a block diagram illustrating a configuration example of the position command generation unit. 10 includes an X axis translational impedance model 911, a Y axis translational impedance model 912, a Z axis translational impedance model 913, an X axis rotational impedance model 914, and a Y axis rotational impedance model 915. , A Z-axis rotational impedance model 916, a demultiplexer 917, a multiplexer 918, a Jacobian matrix calculation unit 919, a disturbance force calculation unit 920, and an inverse kinematics calculation unit 921. The Jacobian matrix calculation unit 919 receives the joint angle as an input, calculates and outputs a Jacobian matrix that is a conversion matrix from the minute displacement of the robot joint coordinates to the minute displacement of the robot hand coordinates. The disturbance force calculation unit 920 receives the second disturbance torque estimated value as an input, and applies the transposed inverse matrix of the Jacobian matrix output from the Jacobian matrix calculation unit 919 to the second disturbance torque estimated value, whereby the joint coordinate system The expressed disturbance torque is converted into a disturbance force expressed in the hand coordinate system.

  The impedance model of each axis from the X-axis translational impedance model 911 to the Z-axis rotational impedance model 916 is the same as the first axis impedance model 91 shown in FIG. These impedance models calculate a position command for each component of the disturbance force output from the disturbance force calculation unit 920 based on the impedance characteristics set in the impedance model. The demultiplexer 917 outputs the translation force and torque of each axis of X, Y, and Z by decomposing the disturbance force output from the disturbance force calculation unit 920 into components of each axis. The multiplexer 918 combines the output of the impedance model of each axis into one signal and outputs a hand coordinate position command. The inverse kinematics calculation unit 921 receives the hand coordinate position command output from the multiplexer 918 as an input, performs a conversion operation from the robot hand coordinate system to the joint coordinate system, called inverse kinematics calculation, and outputs the hand coordinate position command to the joint. The position command converted into coordinates is output.

  Next, the operation of the robot control apparatus according to the third embodiment will be described. The robot control device shown in FIG. 9 is the same as the robot control device shown in FIG. 7 except for the position command generation unit 9a. Therefore, similarly to the robot control device shown in FIG. 7, the disturbance torque acting on the robot can be estimated with high accuracy. Further, by performing impedance control with a highly accurate disturbance torque estimated value, it is possible to realize impedance control with good impedance characteristics.

  Furthermore, the robot control apparatus shown in FIG. 9 performs impedance control calculation by the hand coordinate system in the position command generation unit 9a. Therefore, when the robot control apparatus according to the present embodiment is applied directly to teaching, it is possible to easily perform an intuitive teaching operation in which the motions of the joints of the robot are linked.

Embodiment 4 FIG.
FIG. 11 is a block diagram illustrating a configuration example of a robot control device according to a fourth embodiment of the present invention and an actuator to which a control command is input from the robot control device. 11, components having the same functions as those of the robot control device shown in FIGS. 1 and 7 are denoted by the same reference numerals, and the description thereof is omitted. The robot controller shown in FIG. 11 has a master-slave configuration in which a slave torque controller 10 is added and a slave robot is added.

  The slave torque control unit 10 uses the second disturbance torque estimated value output from the vibration component removal unit 5 as a torque command, and performs slave control for performing torque control of the actuator 11 of the slave robot installed at the joint of the slave robot. Output a command. The slave torque control unit 10 detects the position of the actuator 11 of the slave robot and outputs a detection signal as a position command.

  The vibration signal generation unit 7a receives the vibration frequency output from the vibration frequency storage unit 6 and the joint angle output from the position control unit 1, and sets the absolute value of the joint angular velocity calculated from the joint angle in advance. The vibration signal is output by switching between the sine wave signal and the zero signal according to the comparison result with the joint angular velocity threshold value.

  Next, the operation of the robot control apparatus according to the fourth embodiment will be described. The robot control device shown in FIG. 11 combines the vibration signal generation unit 7a and the vibration component removal unit 5 to remove the influence of the friction torque from the disturbance torque as in the robot control device shown in FIG. Torque can be estimated with high accuracy. Further, the robot control device shown in FIG. 11 transmits the estimated disturbance torque value to the slave robot, and generates a position command for the master robot in accordance with the actual dynamic characteristics from the torque to the position of the slave robot. By adopting such a configuration, the dynamic characteristics of the slave robot can be reproduced on the master robot, so that the master robot operator can understand the dynamic characteristics of the slave robot and the external force applied to the slave robot. It is possible to remotely control the robot.

  In addition, since the robot control apparatus according to the present embodiment can accurately estimate a disturbance torque having a small magnitude less than or equal to the friction torque by removing the influence of the friction torque from the disturbance torque, it has a good operation feeling. Remote control can be realized.

  The bilateral control that transmits the disturbance torque acting on the master robot to the slave robot and the slave robot position to the master robot position allows the master robot operator to remotely operate the slave robot. In addition, it is known as control that can present the reaction force applied to the slave robot to the operator. As described above, the robot control apparatus of the present embodiment can estimate disturbance torque with high accuracy without using a sensor typified by a force sensor, and is inexpensive bilateral control without using a sensor. This system configuration is useful for realizing a master-slave robot.

  The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

DESCRIPTION OF SYMBOLS 1 Position control part, 2 Actuator, 3 Drive torque estimation part, 4 Disturbance torque calculation part, 5 Vibration component removal part, 6 Vibration frequency memory | storage part, 7, 7a Vibration signal generation part, 8 Addition part, 9, 9a Position command generation , 10 Slave torque controller, 11 Slave robot actuator, 31 Gravitational torque calculator, 32 Joint angular velocity calculator, 33 Friction torque calculator, 34 Adder, 51 Vibration frequency notch filter, 52 Triple frequency notch filter, 53 Low-pass filter, 71 joint angular velocity calculation unit, 72 absolute value calculation unit, 73 joint angular velocity threshold value determination unit, 74 vibration signal calculation unit, 91 first axis impedance model, 92 second axis impedance model, 93 third axis impedance model , 94 4th axis impedance model, 95 5th axis impedance model, 96th 6-axis impedance model, 97 demultiplexer, 98 multiplexer, 901 dead band, 902
Subtraction unit, 903 model inertia storage unit, 904 division unit, 905 speed integrator, 906 friction force calculation unit, 907 position integrator, 911 X-axis translational impedance model, 912 Y-axis translational impedance model, 913 Z-axis translational impedance model, 914 X-axis rotational impedance model, 915 Y-axis rotational impedance model, 916 Z-axis rotational impedance model, 917 demultiplexer, 918 multiplexer, 919 Jacobian matrix computing unit, 920 disturbance force computing unit, 921 inverse kinematics computing unit.

To solve the above problems and achieve the object, the present invention is to provide a robot controller for controlling an actuator for driving the joints of the robot, a vibration frequency storage unit for outputting the stored vibration frequency, the A vibration signal generation unit that receives a joint angle that is a joint angle and the vibration frequency and outputs a vibration signal based on a comparison between an absolute value of a joint angular velocity calculated from the joint angle and a preset joint angular velocity threshold value When, an adder for outputting the corrected obtained by adding the oscillating signal position command to the position command, the inputs the corrected position command, control command, before Symbol Takashi Seki angle and the actuator for controlling the position of said actuator A position control unit that outputs an actual driving torque that is a driving torque of the motor, and a driving torque estimation required to drive the actuator with the joint angle as an input. A driving torque estimation unit that outputs a value, and a disturbance that receives the driving torque estimated value and the actual driving torque as inputs and outputs a difference between the driving torque estimated value and the actual driving torque as a first disturbance torque estimated value A torque calculation unit and a vibration component removal unit that outputs the second disturbance torque estimated value obtained by removing the frequency component of the vibration frequency from the first disturbance torque estimated value, with the first disturbance torque estimated value as an input. It is characterized by providing.

Claims (5)

A robot control device for controlling an actuator that drives a joint of a robot,
A vibration frequency storage unit for outputting the stored vibration frequency;
A vibration signal generation unit that receives the vibration frequency and outputs a vibration signal;
The corrected position command obtained by adding the vibration signal to the position command is input, and a control command for controlling the position of the actuator, a joint angle that is the angle of the joint, and an actual driving torque that is the driving torque of the actuator are output. A position control unit;
A driving torque estimation unit that receives the joint angle as an input and outputs a driving torque estimation value necessary to drive the actuator;
A disturbance torque calculator that receives the estimated drive torque value and the actual drive torque as input, and outputs a difference between the estimated drive torque value and the actual drive torque as a first estimated disturbance torque value;
A vibration component removing unit that receives the first disturbance torque estimated value and outputs a second disturbance torque estimated value obtained by removing the frequency component of the vibration frequency from the first disturbance torque estimated value. A robot control device.   The position command generation part which produces | generates and outputs the said position command by the impedance control based on a predetermined inertial and friction characteristic by using the said 2nd disturbance torque estimated value as an input is provided. Robot controller. The vibration signal generator is
A joint angular velocity calculation unit that inputs the joint angle and outputs a joint angular velocity;
An absolute value calculation unit that inputs the joint angular velocity and outputs an absolute value of the joint angular velocity;
A joint angular velocity threshold determination unit that outputs an absolute value of the joint angular velocity and outputs a joint angular velocity comparison signal by comparison with a preset joint angular velocity threshold;
The robot control apparatus according to claim 1, further comprising: a vibration signal calculation unit that inputs the vibration frequency and the joint angular velocity comparison signal and outputs the vibration signal. The vibration component removing unit is
A notch filter for the vibration frequency of the vibration signal;
The robot control apparatus according to claim 1, further comprising a notch filter for harmonics of a vibration frequency of the vibration signal. The second disturbance torque estimated value is input, and a slave control command is output to an actuator of a slave robot that drives a joint different from the robot,
The robot control apparatus according to claim 1, further comprising a slave torque control unit that outputs a joint angle of an actuator of the slave robot as the position command.

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