ComputerAided_Design_Engineering_amp_Manufactur.pdf

3.8 Conclusion
A reconfigurable fixturing technique must provide for accurate planning, analysis, and automated fixture
construction program. A CAD-based planning and analysis approach for reconfigurable fixturing in CIM
and FMS has been described in this chapter. The approach employs a number of adjustable fixture modules
to locate and hold workpieces of various shapes and sizes. The planning and selection of the fixture
configuration are performed within a CAD environment. This is followed by the kinematic analysis and
verification using the generalized screw pairs carried out by a dedicated software program. The interference
detection is performed next. Finally, the post processing is carried out to generate a configuration file and
robot program. These will consist of all the appropriate information to set up and change the fixture layout
and to perform the assembly operations. Some of the advantages of employing such a system include:
1. Reduction of the lead time and effort associated with the design and manufacture
2. Reduction of the non-productive time between batches in a manufacturing plant
3. Reduction of the overhead cost associated with storing and retrieving a multiplicity of traditional
fixtures
4. Full exploitation of robotic and automated assembly for low- to medium-volume production
batches in FMSs and CIMSs.
Acknowledgments
This research is partially supported by an Australian Research Council (ARC) Small Grant, a Monash
Research Fund (MRF) grant, and a Harold Armstrong Research Fund. The author wishes to thank his
research assistants at Robotics & Mechatronics Research Laboratory, Department of Mechanical Engineering,
Monash University.
References
1. Thompson, B. S. Flexible fixturing—a current frontier in the evolution of flexible manufacturing
cells. ASME Transactions No. 84–WA/Prod–16, pp. 1–7, 1984.
2. Gandhi, M. V., Thompson, B. S., and Maas, D. J., Adaptable fixture design: an analytical and
experimental study of fluidized-bed fixturing. Journal of Mechanics, Transmissions, and Automation
in Design, Vol. 108, 15–21, 1986.
3. Hazen, F. B. and Wright, P. K., Workholding automation: innovations in analysis, design, and
planning. Manufacturing Review, Vol. 3, No. 3, 224–237, 1990.
4. Krauskopf, B., Fixtures for small batch production. Manufacturing Engineering, 41–43, 1984.
5. Shirinzadeh, B., Strategies for planning and implementation of flexible fixturing systems in a computer
integrated manufacturing environment. Computers in Industry, Vol. 30, No. 3, 175–183, 1996.
6. Shirinzadeh, B., Flexible and automated workholding systems. Industrial Robot, Vol. 22, No. 2,
29–34, 1995.
7. Gandhi, M. V. and Thompson, B. S., Automated design of modular fixtures for flexible manufacturing
systems. Journal of Manufacturing Systems, Vol. 5, No. 4, 243–252, 1986.
8. Grippo, P. M., Gandhi, B. S., and Thompson, B. S., The computer-Aided design of modular fixturing
systems. The International Journal of Advanced Manufacturing Technology, Vol. 2, No. 2, 75–88, 1987.
9. Beerma, J. R. and Kals, H. J. J., FIXES, a system for automatic selection of set-ups and design of
fixtures. Annals of the CIRP, Vol. 37, 443–446, 1988.
10. Markus, A., Ruttkay, Zs. and Vancza, J., Automating fixture design—from imitating practice to
understanding principles. Computers in Industry, Vol. 14, 99–108, 1990.
11. Pham, D. T. and Lazaro, A., Autofix—an expert CAD system for jigs and fixtures. Journal of Machine
Tools Manufacturing, Vol. 30, No. 3, 403–411, 1990.
12. Cabadaj, J., Theory of computer-Aided fixture design. Journal of Computers in Industry, Vol. 15,
141–147, 1990.
13. King, L. S. and Hutter, I., Theoretical approach for generating optimal fixturing locations for prismatic
workparts in automated assembly. Journal of Manufacturing Systems, Vol. 12, No. 5, 409–416, 1993.
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