Systems and methods for non-rigid load vibration control

Patent metadata

Field	Value
Publication number	US-11682994-B2
Application number	US-202217682439-A
Country	US
Kind code	B2
Filing date	Feb 28, 2022
Priority date	Sep 18, 2019
Publication date	Jun 20, 2023
Grant date	Jun 20, 2023

Abstract

A system includes a motor configured to be coupled to a non-rigid load and a control system disposed within, or communicatively coupled to, a drive system configured to control an operation of the motor. The control system includes a processor and a memory accessible by the processor. The memory stores instructions that, when executed by the processor, cause the processor to generate a smooth move input profile to control the operation of the motor based on inputs specifying a desired operation of the motor, apply a notch filter having a notch filter frequency to the smooth move input profile to produce a filtered smooth move input profile, and send a command to the drive system based on the filtered smooth move input profile, wherein the command is configured to adjust the operation of the motor.

First claim

The invention claimed is:

1. A non-transitory, tangible, computer readable medium comprising instructions that, when executed by a processor, causes the processor to:
receive inputs specifying a desired operation of an end effector of a robot, wherein the end effector of the robot is driven by a motor communicatively coupled to a drive system, wherein the end effector of the robot is non-rigid;
generate a smooth move input profile to control the operation of the motor based on the inputs specifying the desired operation of the end effector of the robot, wherein a second derivative of the smooth move input profile is piece-wise continuous;
apply a notch filter to the smooth move input profile to produce a filtered smooth move input profile, wherein the notch filter has a notch filter frequency that is determined based on a resonant frequency of the end effector of the robot; and
send a command to the drive system based on the filtered smooth move input profile, wherein the command is configured to adjust the operation of the motor.

2. The computer readable medium of claim 1 , wherein the processor is configured to be communicatively coupled to a sensor configured to collect data corresponding to the end effector of the robot during actuation of the motor, wherein the processor is configured to generate a supplemental input signal to adjust the operation of the motor based on the collected data.

3. The computer readable medium of claim 1 , wherein supplemental input signal is conditioned by a proportional integral (PI) process block.

4. The computer readable medium of claim 1 , wherein the motor comprises a robot actuator.

5. The computer readable medium of claim 1 , wherein the smooth move input profile comprises a cubic function, a 5th order polynomial function, a 7th order polynomial function, a sinusoidal function, a modified sine function, a sine squared function, or a combination thereof.

6. The computer readable medium of claim 1 , wherein the notch filter is defined by an adjustable notch width, an adjustable notch depth, and an adjustable gain.

7. The computer readable medium of claim 1 , wherein the motor comprises a servo.

8. The computer readable medium of claim 1 , wherein the motor comprises a rotational electric motor.

9. A system, comprising:
a robot comprising an end effector;
a rotational motor configured to be coupled to the end effector of the robot via a compliant linkage;
a control system disposed within, or communicatively coupled to, a drive system configured to control an operation of the rotational motor to control movement of the end effector of the robot, the control system comprising:
a processor; and
a memory accessible by the processor, the memory storing instructions that, when executed by the processor, cause the processor to:
generate a smooth move input profile to control the operation of the rotational motor based on inputs specifying a desired operation of the end effector of the robot, wherein a second derivative of the smooth move input profile is piece-wise continuous;
apply a notch filter to the smooth move input profile to produce a filtered smooth move input profile, wherein the notch filter has a notch filter frequency that is determined based on a resonant frequency of the end effector; and
send a command to the drive system based on the filtered smooth move input profile, wherein the command is configured to control the movement of the end effector.

10. The system of claim 9 , comprising a sensor configured to collect data corresponding to the end effector during the operation of the end effector, wherein the control system is configured to generate a supplemental input signal to control the movement of the end effector based on the collected data.

11. The system of claim 9 , wherein supplemental input signal is conditioned by a proportional integral (PI) process block.

12. The system of claim 11 , wherein the control system comprises a user interface element configured to control an adjustable integral gain of the supplemental input signal.

13. The system of claim 9 , wherein the smooth move input profile comprises a cubic function, a 5th order polynomial function, a 7th order polynomial function, a sinusoidal function, a modified sine function, a sine squared function, or a combination thereof.

14. The system of claim 9 , wherein the notch filter is defined by a notch width, a notch depth, and a gain.

15. The system of claim 9 , wherein the desired operation of the end effector comprises a desired location of the end effector.

16. The system of claim 9 , wherein the rotational motor comprises a servo.

17. The system of claim 9 , wherein the rotational motor comprises an electric rotational motor.

18. A method, comprising:
generating, via a control system, a smooth move input profile to control actuation of a motor coupled to an end effector of a robot via a compliant linkage based on inputs specifying a desired operation of the end effector of the robot, wherein a second derivative of the smooth move input profile is piece-wise continuous;
applying, via the control system, a notch filter to the smooth move input profile to produce a filtered smooth move input profile, wherein the notch filter has a notch filter frequency that is determined based on a resonant frequency of the end effector; and
sending, via the control system, a command to a drive system based on the filtered smooth move input profile, wherein the command is configured to adjust the operation of the motor.

19. The method of claim 18 , comprising:
collecting, via a sensor, data corresponding to the end effector during actuation of the motor;
generating, via the control system, a supplemental input signal to adjust the operation of the end effector based on the collected data; and
sending, via the control system, the supplemental input signal to the drive system.

20. The method of claim 18 , wherein the notch filter is defined by an adjustable notch width, an adjustable notch depth, and an adjustable gain.

Assignees

• Rockwell Automation Tech Inc

Inventors

• Miklosovic Robert J
• Fast Brian

Classifications

• H02P23/04 Primary

  specially adapted for damping motor oscillations, e.g. for reducing hunting · CPC title

• G05B19/0423 Primary

  Input/output · CPC title

• H02P23/0004

  Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control · CPC title

• B66C13/063

  electrical · CPC title

• G05B2219/41217

  Command preshape, guidance, reference for better dynamic response, forcing feedforward · CPC title