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

• US 6,920,408 B2
• Filed: 05/12/2003
• Issued: 07/19/2005
• Est. Priority Date: 04/26/2001
• Status: Active Grant

• 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
• Application Number:
  US10/436,029
• Publication Number:
  US 20040193385A1
• Time in Patent Office: 799 Days
• Field of Search: 318/616, 318/571, 318/568.1, 318/568.18, 318/638, 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 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 controller is further adapted to provide a setup interface that enables a user of the machine tool to design a test capable of causing the signal to be commanded.

2. The machine tool 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.

3. The machine tool of claim 1, wherein the controller is further adapted to prompt a user of the machine tool to setup a device capable of outputting the measurement data associated with the actual motion.

4. The machine tool of claim 3, wherein the controller being adapted to prompt a user of the motion control system to setup a device further comprises the controller being adapted to provide a test interface capable of aiding a user of the machine tool in setting up the device.

5. The machine tool of claim 1, wherein the controller is further adapted to:

cause the signal to be commanded again;

acquire additional control data associated with the signal;

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

analyze the additional data.

6. The machine tool of claim 1, wherein the controller being adapted to analyze the data comprises the controller being further adapted to:

determine error from the data;

associate the error with a parametric model; and

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

7. The machine tool of claim 6, wherein the controller being adapted to associate the error with a parametric model comprises the controller to be further adapted to fit the error to a curve.

8. The machine tool of claim 6, wherein the controller is further adapted to determine an ability of the parametric model to account for the error.

9. The machine tool of claim 1, wherein the controller being adapted to receive an indication of a compensation parameter to be tested comprises the controller being further adapted to provide 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.

10. The machine tool of claim 9, wherein the controller is further adapted to validate the test condition parameter, wherein it is determined if the desired motion is appropriate based upon the test condition parameter.

11. The machine tool of claim 10, wherein the controller being adapted to validate the test condition parameter comprises the controller being further adapted to describe a problem associated with the desired motion if the test condition parameter is not validated.

12. The machine tool of claim 1, wherein the controller being adapted to cause a signal to be commanded comprises the controller being further adapted to:

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

execute the set of instructions.

13. The machine tool of claim 1, wherein the controller being adapted to analyze the data further comprises the controller being adapted to provide an analysis interface capable of displaying an analysis of the data.

14. The machine tool of claim 1, wherein the controller being adapted to implement the value comprises the controller being further adapted to:

suggest the value for the compensation parameter;

receive 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, implement the value of the compensation parameter.

15. The machine tool of claim 14, wherein the controller being adapted to suggest a value for the compensation parameter further comprises the controller being adapted to provide a diagnostics interface capable of allowing the value of the compensation parameter to be adjusted.

16. The machine tool of claim 15, wherein the controller being adapted to provide a diagnostics interface further comprises the controller being adapted to provide 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.

17. The machine tool of claim 14, wherein the controller being adapted to provide a diagnostics interface further comprises the controller being adapted to display predicted affects if the value is adjusted.

18. The machine tool of claim 1, wherein the controller being adapted to implement the value comprises the controller being further adapted to:

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

if received, implement the changes to the value of the compensation parameter in the machine tool.