OPEN ACCESS
There have been many interesting technical ideas and parallels in thinking that have resulted from the technical discussions that I have had with Professor Jerome J. Connor since 1986. This brief article provides a context and reflects upon his mentorship, which helped shape the thinking of a then young professor from another University, and on the impact that Professor Connor has had on his students and others beyond the halls of MIT’s Building 1. The optimization topic presented here provides an example of that influence. Extracting the desired response information from an instrumented slender structure, while minimizing the number of sensors, is a challenging problem requiring well-defined objectives that can be used in an optimization process. In this study, a methodology that builds upon a Genetic Algorithm optimization procedure is used to investigate sensor placement needed to recover specific vibration modes. Data recorded from an experiment investigating the flow-induced vibration of a smooth horizontally towed cylinder is used to explore the optimization process and subtleties associated with its application subject to single or multiple objectives and gaps in sensor data due to several possible constraints. The use of the Paterno Front Method and the difficulty in accurately capturing higher modes are addressed.
Fiber optic sensors, genetic algorithm, intelligent system design, mode recovery, multiple sensors, optimization, slender structures
[1] Winston, P.H., Artificial Intelligence, 2nd edn., Addison-Wesley Publishing Company, Inc.: USA, 1984.
[2] Minsky, M. & Papert, S., Preceptrons: Expanded Edition, MIT Press: Cambridge, MA, 1988.
[3] Abelson, H., Sussman, G.J. & Sussman, J., Structure and Interpretation of Computer Programs, MIT Press: Cambridge, MA, 1985. doi: http://dx.doi.org/10.2307/3679579
[4] Connor, J.J., Niedzwecki, J.M. & Guo, R.S., Intelligent mesh design for discrete element analysis, Artificial Intelligence in Engineering Conference, MIT: Cambridge, MA, 1987.
[5] Chehayeb, F., Niedzwecki, J.M., & Connor, J.J., A knowledge based approach to innovative design. Artificial Intelligence in Engineering Conference, MIT: Cambridge, MA, 1987. doi: http://dx.doi.org/10.1016/0954-1810(87)90170-1
[6] Chehayeb, F., Connor, J.J. & Niedzwecki, J.M., Innovative engineering design. Microcomputers in Civil Engineering, 4(1), pp. 1–9, 1989. doi: http://dx.doi.org/10.1111/j.1467-8667.1989.tb00001.x
[7] Niedzwecki, J.M. & Earles, J., Strategy for design of intelligent tutoring systems. ASCE Journal of Computing in Civil Engineering, 5(2), pp. 211–229, 1991. doi: http://dx.doi.org/10.1061/(ASCE)0887-3801(1991)5:2(211)
[8] Niedzwecki, J.M. & Rijken, O.R., Preliminary design of Tension Leg Platforms using a knowledge based approach. ASCE Ocean’s V, 1, pp. 288–293, 1992.
[9] Connor, J.J. & Faraji, S., Fundamentals of Structural Engineering, Springer International Publishing: New York, 2013.
[10] Connor, J.J. & LaFlamme, S., Structural Motion Engineering, Springer International Publishing: New York, 2014.
[11] Coley, D.A., An Introduction to Genetic Algorithms for Scientists and Engineers, World Scientific: New Jersey, 2005.
[12] Fang, S.M., Structural Response Evaluation Using Non-uniform Sensor Arrays, Dissertation, Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, 2013.
[13] Fu, S., Ren, T., Li, R. & Wang, X., Experimental investigation on VIV of the flexible model under full scale Re number. Proc. Offshore Mechanics and Arctic Engineering, No. 49042, 2011. doi: http://dx.doi.org/10.1115/OMAE2011-49042
[14] Li, L., Fu, S., Yang, J., & Ren, T., Experimental investigation on VIV of risers with staggered buoyancy. Proc. Offshore Mechanics and Arctic Engineering, No. 49046, 2011. doi: http://dx.doi.org/10.1115/omae2011-49046
[15] Niedzwecki, J.M. & Fang, S.M., Suppression of flow-induced vibrations using ribbon fairings. Journal of Computational Methods and Experimental Measurements, 1(4), pp. 395–405, 2013. doi: http://dx.doi.org/10.2495/cmem-v1-n4-395-405
[16] Fang, S.M. & Niedzwecki, J.M., Comparison of airfoil and ribbon fairings for suppression of flow-induced vibrations. Journal of Computational Methods and Experimental Measurements, 2(1), pp. 30–45, 2014. doi: http://dx.doi.org/10.2495/cmem-v2-n1-30-45
[17] Fang, S.M., Niedzwecki, J.M., Fu, S., Li, R. & Yang, J., VIV response of a flexible cylinder with varied coverage by buoyancy elements and helical strakes. Marine Structures, 39, pp. 70–89, 2014. doi: http://dx.doi.org/10.1016/j.marstruc.2014.06.004
[18] Niedzwecki, J.M. & Fang, S.M., Hydrodynamic response of ribbon fairing. Proc. Oceans 2013 MTS/IEEE, San Diego, CA, 2013.