Method and apparatus for tuning compensation parameters in a motion control system associated with a mechanical member

• US 6,865,499 B2
• Filed: 04/17/2002
• Issued: 03/08/2005
• Est. Priority Date: 04/26/2001
• Status: Expired due to Term

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: Yutkowitz, Stephen J.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): BHAT, ADITYA S
• Application Number:
  US10/124,639
• Publication Number:
  US 20030036868A1
• Time in Patent Office: 1,056 Days
• Field of Search: 318/616, 318/571, 318/568.1, 318/568.18, 318/638, 318/632, 702/105, 700/37, 700/45, 385/37, 348/164, 714/25
• US Class Current: 702/105
• CPC Class Codes: G05B 19/404 characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia G05B19/19, G05B19/41 take precedence
• CPC Class Codes: G05B 2219/49181 Calculation, estimation, creation of error model using measured error values

Abstract

In one embodiment, a method and machine are provided for tuning compensation parameters in a motion control system associated with a mechanical member. The method includes the steps of receiving an indication of a compensation parameter to be tested, based on the compensation parameter to be tested causing a signal associated with a desired motion of the mechanical member to be commanded, acquiring control data associated with the signal, acquiring measurement data associated with actual motion of the mechanical member in response to the signal, analyzing the control and measurement data; and based on the step of analyzing the control and measurement data, implementing a value of the compensation parameter.

Claims

1. A method for tuning compensation parameters in a motion control system associated with a mechanical member, the method comprising:

a) receiving an indication of a compensation parameter to be tested;

b) based on the compensation parameter to be tested, causing a signal associated with a desired motion of the mechanical member to be commanded;

c) acquiring control data associated with the signal;

d) acquiring measurement data associated with actual motion of the mechanical member in response to the signal;

e) analyzing the control and measurement data;

f) based on the step of analyzing the control and measurement data, implementing a value of the compensation parameter;

wherein the step of analyzing the data comprises the steps of;

determining error from the data;

associating the error with a parametric model; and

extracting the value for the compensation parameter from the parametric model.

2. The method of claim 1, wherein the step of associating the error with a parametric model comprises the step of fitting the error to a curve.

3. The method of claim 1, further comprising the step of determining an ability of the parametric model to account for the error.

6. The method of claim 1, further comprising the step of providing a setup interface that enables a user of the motion control system to design a test capable of causing the signal to be commanded.

7. The method of claim 1, further comprising the step of prompting a user of the motion control system to setup a device capable of outputting the measurement data associated with the actual motion.

8. The method of claim 7, wherein the step of prompting a user of the motion control system to setup a device comprises the step of providing a test interface capable of aiding a user of the motion control system in setting up the device.

9. The method of claim 1, further comprising the steps of:

causing the signal to be commanded again;

acquiring additional control data associated with the signal;

acquiring additional measurement data associated with new actual motion of the mechanical member; and

analyzing the additional data.

10. The method of claim 1, wherein the step of receiving an indication of a compensation parameter to be tested comprises the step of providing a setup interface that allows a test condition parameter to be entered, wherein the desired motion corresponds to the test condition parameter that is entered.

11. The method of claim 10, further comprising the step of validating the test condition parameter, wherein it is determined if the desired motion is appropriate based upon the test condition parameter.

12. The method of claim 11, wherein the step of validating the test condition parameter comprises the step of describing a problem associated with the desired motion if the test condition parameter is not validated.

13. The method of claim 1, wherein the step of causing a signal to be commanded comprises the steps of:

automatically generating a set of instructions designed to cause the desired motion when executed; and

executing the set of instructions.

14. The method of claim 1, wherein the step of analyzing the data further comprises the step of providing an analysis interface capable of displaying an analysis of the data.

15. The method of claim 1, wherein the step of implementing the value comprises the steps of:

suggesting the value for the compensation parameter;

receiving an indication with respect to acceptance of the value suggested for the compensation parameter; and

if an indication with respect to acceptance of the value suggested for the compensation parameter is received, implementing the value of the compensation parameter.

16. The method of claim 15, wherein the step of suggesting a value for the compensation parameter further comprises the step of providing a diagnostics interface capable of allowing the value of the compensation parameter to be adjusted.

17. The method of claim 16, wherein the step of providing a diagnostics interface further comprises providing a diagnostics interface capable of displaying an error source and the value of the compensation parameter as suggested, and capable of receiving an indication of whether the value as suggested should be accepted.

18. The method of claim 15, wherein the step of providing a diagnostics interface further comprises displaying predicted affects if the value is adjusted.

19. The method of claim 1, wherein the step of implementing the value comprises the steps of:

providing an adjustment interface capable of receiving changes to the value of the compensation parameter; and

if received, implementing the changes to the value of the compensation parameter in the motion control system.

20. The method of claim 1, wherein the compensation parameter compensates for at least one of a scale error, a squareness error, a straightness error, backlash, windup and friction.

4. A computer readable medium comprising instructions capable of implementing a method for tuning compensation parameters in a motion control system associated with a mechanical member, the method comprising:

a) receiving an indication of a compensation parameter to be tested;

b) based on the compensation parameter to be tested, causing a signal associated with a desired motion of the mechanical member to be commanded;

c) acquiring control data associated with the signal;

d) acquiring measurement data associated with actual motion of the mechanical member in response to the signal;

e) analyzing the control and measurement data;

f) based on the step of analyzing the control and measurement data, implementing a value of the compensation parameter;

wherein the step of analyzing the data comprises the steps of;

determining error from the data;

associating the error with a parametric model; and

extracting the value for the compensation parameter from the parametric model.

21. The computer readable medium of claim 4, wherein the compensation parameter compensates for at least one of a scale error, a squareness error, a straightness error, backlash, windup and friction.

5. A machine tool, comprising:

a) an actuator having an attached mechanical member;

b) a motion command generator adapted to produce motion commands capable of controlling the actuator;

c) a compensator adapted to compensate the motion commands based upon at least one compensation parameter;

d) a controller in communication with the actuator, the motion command generator, and the compensator, and adapted to;

i) receive an indication of a compensation parameter to be tested;

ii) based on the compensation parameter to be tested, cause a signal associated with a desired motion of the mechanical member to be commanded;

iii) acquire control data associated with the signal;

iv) acquire measurement data associated with actual motion of the mechanical member in response to the signal;

v) analyze the control and measurement data;

vi) based on the step of analyzing the control and measurement data, implement a value of the compensation parameter;

wherein the step of analyzing the data comprises the steps of;

determining error from the data;

associating the error with a parametric model; and

extracting the value for the compensation parameter from the parametric model.

22. The computer readable medium of claim 5, wherein the compensation parameter compensates for at least one of a scale error, a squareness error, a straightness error, backlash, windup and friction.