Dynamic control system for manufacturing processes including indirect process variable profiles

• US 7,840,297 B1
• Filed: 03/14/2008
• Issued: 11/23/2010
• Est. Priority Date: 03/14/2008
• Status: Expired due to Fees

• Current Assignee: Steve W. Tuszynski
• Original Assignee: Steve W. Tuszynski
• Inventors: Tuszynski, Steve W.
• Primary Examiner(s): BARNES-BULLOCK, CRYSTAL JOY
• Application Number:
  US12/048,534
• Time in Patent Office: 984 Days
• Field of Search: 700 28- 30, 700 32- 34, 700/44, 700/95, 700/97, 700/103, 700/105, 700108-110, 700/173, 700/174, 702182-185, 703/2, 706/16, 706/19, 706/21
• US Class Current: 700/108
• CPC Class Codes: G05B 13/048 using a predictor
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: G05B 2219/32188 Teaching relation between controlling parameters and quality parameters
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
• CPC Class Codes: Y02P 90/80 Management or planning

Abstract

Methods, apparatuses and systems that facilitate the design, production, control and/or measurement tasks associated with manufacturing and other processes. In one implementation, the present invention facilitates or enables the use of indirect process variables for use in manufacturing or other processes that yield articles or parts. For example, it enables determining a desired value profile for an indirect process variable based on the operating target, the lower operating limit and the upper operating limit for the predictor characteristic, and observations of the process. In one implementation, the present invention facilitates qualifying articles resulting from the process by comparing the desired versus observed value profiles for an indirect process variable. In another implementation, the present invention facilitates controlling a direct process variable based on the observed versus desired values of an indirect process variable.

Claims

1. A method facilitating design and manufacturing processes, the method comprising

selecting a predictor characteristic from a plurality of article characteristics resulting from a process based on a plurality of article characteristic values associated with a set of articles having a range of variation as to the plurality of article characteristics;

determining the regression model(s) between the predictor characteristic and at least one of the remaining article characteristics in the plurality of article characteristics;

determining an operating target for the predictor characteristic based on a set of design tolerances and the regression model(s);

determining a desired value profile for an indirect process variable of the process based on the operating target for the predictor characteristic, and observations of the process; and

monitoring, during execution of the process, an observed value profile of the indirect process variable of the process relative to the desired value profile for the indirect process variable to qualify articles resulting from the process.

2. The method of claim 1 wherein the determining the desired value profile for the indirect process variable comprises

determining one or more direct process variable settings where the process yields articles with the predictor characteristic substantially at the operating target;

observing values of the indirect process variable during execution of the process at the one or more direct process variable settings to determine the desired value profile for the indirect process variable.

3. The method of claim 1 further comprising accepting the articles resulting from the process based on a comparison of the observed value profile for the indirect process variable to the desired value profile.

4. The method of claim 1 further comprising changing one or more direct process variable settings of the process based on a comparison of the observed value profile for the indirect process variable to the desired value profile.

5. The method of claim 1 wherein the desired value profile is time-dependent.

6. The method of claim 1 wherein the desired value profile is time-dependent and associated with an iteration of the process.

7. The method of claim 1 wherein the desired value profile comprises upper and lower tolerances for the indirect process variable.

8. The method of claim 1 wherein the desired value profile comprises a range of time-integrated values of the indirect process variable.

9. The method of claim 1 wherein the desired value profile comprises a range of time-derivative values of the indirect process variable.

10. The method of claim 1 further comprising

controlling, during execution of the process, an attribute of the process based on observed values of the indirect process variable resulting from the process relative to the desired value profile for the indirect process variable.

11. The method of claim 10 wherein the attribute of the process is a direct process variable.

12. The method of claim 10 wherein the process is an injection molding process and wherein the desired value profile is a pressure-versus-time profile.

13. A method facilitating design and manufacturing processes, the method comprising

selecting a predictor characteristic from a plurality of article characteristics resulting from a process based on a plurality of article characteristic values associated with a set of articles having a range of variation as to the plurality of article characteristics;

determining the regression model(s) between the predictor characteristic and at least one of the remaining article characteristics in the plurality of article characteristics;

determining an operating target for the predictor characteristic based on a set of design tolerances and the regression model(s);

determining a desired value profile for one or more indirect process variables of the process based on the operating target for the predictor characteristic, and observations of the process; and

monitoring, during execution of the process, an observed value profile of the one or more indirect process variables of the process relative to the desired value profile for the one or more indirect process variables to qualify articles resulting from the process.

14. A method facilitating design and manufacturing processes, the method comprising

selecting a predictor characteristic from a plurality of article characteristics resulting from a process based on a plurality of article characteristic values associated with a set of articles having a range of variation as to the plurality of article characteristics;

determining the regression model(s) between the predictor characteristic and at least one of the remaining article characteristics in the plurality of article characteristics;

determining an operating range for the predictor characteristic based on a set of design tolerances and the regression model(s);

determining a desired value profile for an indirect process variable of the process based on the operating range, and observations of the process; and

monitoring, during execution of the process, an observed value profile of the indirect process variable of the process relative to the value profile for the indirect process variable to qualify articles resulting from the process.

15. The method of claim 14 wherein the determining the desired value profile for the indirect process variable comprises

determining a first set of one or more direct process variable settings where the process yields articles with the predictor characteristic substantially at a lower end of the operating range;

determining a second set of one or more direct process variable settings where the process yields articles with the predictor characteristic substantially at an upper end of the operating range;

observing values of the indirect process variable during execution of the process at the first and second sets of the one or more direct process variable settings to determine the desired value profile for the indirect process variable, wherein the desired value profile includes lower and upper tolerance bands.

16. The method of claim 14 further comprising accepting the articles resulting from the process based on a comparison of an observed value profile for the indirect process variable to the desired value profile.

17. The method of claim 14 further comprising changing one or more direct process variable settings of the process based on a comparison of an observed value profile for the indirect process variable to the desired value profile.

18. The method of claim 14 wherein the desired value profile is time-dependent.

19. The method of claim 14 wherein the desired value profile is time-dependent and associated with an iteration of the process.

20. The method of claim 14 wherein the desired value profile comprises upper and lower tolerances for the indirect process variable.

21. The method of claim 14 wherein the desired value profile comprises a range of time-integrated values of the indirect process variable.

22. The method of claim 14 wherein the desired value profile comprises a range of time-derivative values of the indirect process variable.