On the dynamic response of actuation devices in nonlinear dynamics systems

Patent metadata

Field	Value
Publication number	US-9455654-B2
Application number	US-201414301304-A
Country	US
Kind code	B2
Filing date	Jun 10, 2014
Priority date	Jun 10, 2013
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A method for actuating a motor including: separating feed-forward signals corresponding to motion independent components of a required actuating force/torque from motion dependent components; filtering the motion dependent components of the feed-forward signals to at least reduce high frequency signals generated due to feedback signals; and either not filtering or filtering with a low pass filter having a higher cut off frequency the motion independent components of the feed-forward signals to at least reduce higher frequency noise and components; wherein higher frequency components of electronic power amplifier signals corresponding to the motion independent components of the actuating forces/torques are not eliminated by the low pass filter, thereby ensuring that the reaction forces/torques are provided to actuate the motor.

First claim

What is claimed is:

1. A method of controlling an actuation device to move an actuator, the method comprising acts of:
receiving information on a starting first position and an indication of an actuator output to move the actuator from the starting first position to a second position;
dividing the indicated actuator output into motion dependent components and motion independent components;
determining a difference between the first and second positions;
combining the difference between the first and second positions with the motion dependent components producing a first combined result;
filtering the first combined result removing one or more high frequency components beyond a dynamic response capability of the actuator producing a first filtered result;
combining the first filtered result with the motion independent components producing a second combined result;
converting the second combined result to a power signal for driving the actuator; and
driving the actuator with the power signal.

2. The method of claim 1 , comprising acts of:
determining an updated first position resulting from driving the actuator;
repeating the acts of determining the difference, combining the difference, filtering the first combined result, combining the first filtered result, converting the second combined result and driving the actuator for a given period of time.

3. The method of claim 1 , wherein the indication of the motion includes both a force and a torque component and the act of dividing comprises acts of determining force and torque motion dependent components and force and torque motion independent components.

4. The method of claim 1 , wherein the act of determining the difference between the first and second positions comprises an act of subtracting the second position from the first position to determine the difference.

5. The method of claim 1 , wherein the act of combining the difference between the first and second positions with the motion dependent components comprises an act of adding the difference between the first and second positions to the motion dependent components to produce the first combined result.

6. The method of claim 1 , wherein the act of combining the first filtered result with the motion independent components comprises an act of adding the first filtered result with the motion independent components to produce the second combined result.

7. The method of claim 1 , comprises an act of moving an object to the second position by the driven actuator.

8. The method of claim 1 , wherein the actuator is a robotic manipulator.

9. The method of claim 1 , wherein the actuator is a motor.

10. The method of claim 9 , wherein the indication of the motion includes both a force and a torque component and the act of dividing comprises acts of determining force and torque motion dependent components and force and torque motion independent components.

11. The method of claim 1 , wherein the motion to move the actuator includes a related velocity and acceleration.

12. An apparatus for controlling an actuator, the device comprising:
an actuator; and
a control portion coupled to the actuator, wherein the control portion comprises:
an input portion to receive information on a starting first position and an indication of an actuator output to move the actuator from the starting first position to a second position,
a separator configured to separate the indicated actuator output into motion dependent components and motion independent components,
a subtractor coupled to receive the information on the first and second positions to produce a difference between the first and second positions,
a first adder coupled to receive the difference between the first and second positions and the motion dependent components to produce a first combined result,
a low pass filter coupled to receive the first combined result removing one or more high frequency components beyond a dynamic response capability of the actuator to produce a first filtered result, and
a second adder coupled to receive the first filtered result and the motion independent components to produce a second combined result to drive the actuator.

13. The apparatus of claim 12 , comprising an amplifier coupled to receive the second combined result to produce a power signal to drive the actuator.

14. The apparatus of claim 12 , wherein the separator is configured to separate the indicated motion into force and torque motion dependent components and force and torque motion independent components.

15. The apparatus of claim 12 , wherein the actuator is a robotic manipulator.

16. The apparatus of claim 12 , wherein the actuator is a motor.

17. A robotic manipulator comprising:
an actuator; and
and a control portion coupled to the actuator, wherein the control portion comprises:
an input portion to receive information on a starting first position and an indication of an actuator output to move the actuator from the starting first position to a second position,
a separator configured to separate the indicated actuator output into motion dependent components and motion independent components,
a subtractor coupled to receive the information on the first and second positions to produce a difference between the first and second positions,
a first adder coupled to receive the difference between the first and second positions and the motion dependent components to produce a first combined result,
a low pass filter coupled to receive the first combined result removing one or more high frequency components beyond a dynamic response capability of the actuator to produce a first filtered result, and
a second adder coupled to receive the first filtered result and the motion independent components to produce a second combined result to drive the actuator.

18. The robotic manipulator of claim 17 , comprising an amplifier coupled to receive the second combined result to produce a power signal to drive the actuator.

Assignees

• Rastegar Jahangir S
• Feng Dake
• Omnitek Partners Llc

Inventors

• Rastegar Jahangir S
• Feng Dake

Classifications

• H02P6/08 Primary

  Arrangements for controlling the speed or torque of a single motor (H02P6/10, H02P6/28 take precedence) · CPC title

• B25J9/1628

  characterised by the control loop · CPC title

• H02P2207/05

  Synchronous machines, e.g. with permanent magnets or DC excitation · CPC title

• G05B2219/42153

  Inverse dynamics model idm, computed torque method · CPC title

• G05B2219/41426

  Feedforward of torque · CPC title