Intelligent Control of the Thermoplastic Composite Tow-Placement Process

Abstract

Model-based control in the manufacturing of advanced composite materials is one approach to improve the overall quality and performance of the final part. Frequently, quantitative nondestructive methods are not available for feedback control, and therefore a predictive controller is required. This study investigates a neural-network-based control system for the automated thermoplastic composite tow-placement process. This non-autoclave process incorporates an advanced controller that predicts desired part quality at minimal cost. The control system combines a neural network (NN) based model. numerical and neural network optimization, and an infrared thermal imaging camera to sense the temperature profile on the part surface. The optimization utilizes the NN process model to calculate the optimum inputs for the desired quality, whereas the image camera is used for temperature feedback control.

References

1. Inventors: J. W. Gillespie, Jr.. R. C. Don, S. T. Holmes and I. Howie. 1997. Adjustable Hot Gas Torch Nozzle for Rapid Heating Control, U.S. Patent No. 5.626.472. May 6.

2. Mantell, S. C. , and G. S. Springer . 1992. "Manufacturing Process Models for Thermoplastic Composites," Journal of Composite Materials, 26(16):2348-2377.

3. C. A. Butler . R. Pitchumani . J. W. Gillespie. Jr. , and A. G. Wedgewood . 1994. "Coupled Effects of Healing and Intimate Contact on the Strength of Fusion-Bonded Thermoplastics," Proceedings of the 10th Annual ASMIESD Advanced Composites Conference, Dearborn, Ml. pp. 595-604.

4. Ersoy. N. B. . O. Vardar . B. K. Fink , and J. W. Gillespie Jr. 1995. "Effect of Processing Variables on Consolidation and Bonding in the Thermoplastic Fiber Placement Process." Centerfor Composite Materials Technical Report 95-35, University of Delaware.

5. Pitchumani. R. , R. C. Don . J. W. Gillespie Jr. , M. A. Lamontia and S. Ranganathan . 1996. "Analysis of Transport Phenomena Governing Interfacial Bonding and Void Dynamics During Thermoplastic Tow-Placement." International Journal of Heat and Mass Transfer, 39(9):1883-1897.

6. Tierney. J. J. R. F. Eduljee , and J. W. Gillespie, Jr. 1995. " Material Response During Robotic Tow Placement of Thermoplastic Composites." Proceedings of the Ith Annual Advanced Composites Conference, pp. 315-329.

7. Tierney, J. J. . D. Heider and J. W. Gillespie Jr. 1997. "Welding of Thermoplastic Composites Using The Automated Tow Placement Process: Modeling and Control,"

Proceedings ANTEC 97

Toronto. Ontario. pp. 1165-1170.

8. Hornik. K. . M. Stinchcome and H. White . 1989. "Multilayer Feedforward Networks Are Universal Approximators." Neural Networks, 2(5):359-366.

9. Albus. J. S. 1975. "A New Approach To Manipulator Control: The Cerebellar Model Articulation Controller (CMAC)." Transactions of the ASME, Journal of Dynamical Systems, Measurement, and Control, pp. 220-227.

10.

10. Damarla. T.R. , W. N. Zhao . "A Learning Algorithm For A CMAC-Based System And Its Application For Classification Of Ultrasonic Signals.." Ultrasonics, 32(2)91-97.

11.

11. Nelson. J. . and L. G. Kraft . 1995. "Using CMAC Neural Networks And Optimal Control." IEEE International Conference of Neural Networks, pp. 2386-2390.

12.

12. Miller. W.T. . Glanz F. H. and L. G. Kraft . 1990. "CMAC: An Associative Neural Network Alternative To Backpropagation." Proceedings of the IEEE, 78(10):1561-1567.

13.

13. Warwick. K. . C. Kambhampati . P. Parks and J. Mason . 1995. "Dynamic Systems in Neural Networks." Neural Netw ork Engineering in Dynamic Control Systems (Advances in Industrial Control Series), II. Series, Springer, pp.27-41.

14.

14. Werbos. P. J. 1991. "An Overview of Neural Networks for Control." IEEE Control Systems Mlagazine. 11(1):40-41.

15.

15. Zell. A. . G. Mamier . M. Vogt . N. Mache . R. Hubner . K. Herrmann . T. Soyez . M. Schmalzl . T. Sommer , A. Hatzigeorgiou . S. Doring and D. Posselt . 1994. SNNS User Manual, Version 3.2. University of Stuttgart, Institute for Parallel and Distributed High Performance Systems. Report No. 3.

16.

16. Bunday. B.D. and Garside. G.R. 1987. Optimization Methods in PASCAL, Edward Arnold.