Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Structure-Control Combined Design with Structure Intensity

  • PARK JUNG-HYEN (School of Automotive Mechanical Engineering, Silla University) ;
  • KIM SOON HO (School of Automotive Mechanical Engineering, Silla University)
  • Published : 2003.10.01
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Abstract

This paper proposes an optimum design method of structural and control systems, using a 2-D truss structure as an example. The structure is subjected to initial static loads and disturbances. For the structure, a FEM model is formed. Using modal transformation, the equation of motion is transformed into modal coordinates, in order to decrease D.O.F. of the FEM model. To suppress the effect of the disturbances, the structure is controlled by an output feedback $H_{\infty}$ controller. The design variables of the combined optimal design of the control-structure systems are the cross sectional areas of truss members. The structural objective function is the structural weight. The control objective function is the $H_{\infty}$ norm, the performance index of control. The second structural objective function is the energy of the response related to the initial state, which is derived from the time integration of the quadratic form of the state in the closed-loop system. In a numerical example, simulations have been perform. Through the consideration of structural weight and $H_{\infty}$ norm, an advantage of the combined optimum design of structural and control systems is shown. Moreover, since the performance index of control is almost nearly optimiz, we can acquire better design of structural strength.

Keywords

References

  1. Box. M.J., Davies. D. and Swann. W.H. (1972). Nonlinear Optimization Methods, Baihukan Press
  2. Grandhi. R.V. (1989). "Structural and Control Optimization of Space Structures", Journal of the Computers and Structures, Vol 31, No 2, pp 139-150 https://doi.org/10.1016/0045-7949(89)90222-8
  3. Kajiwara. H., Tsujioka. D. and Nagamats. J. (1993). "Simultaneous Optimum Design of Structural and Control Systems by Complex Method", Trans. of JSME. Vol 59, No. 563, pp 2124-2131 https://doi.org/10.1299/kikaic.59.2124
  4. Khot. N.S. (1998). "Structure/Control Optimization to Improve the Dynamic Response of Space Structures", J. of the Computational Mechanics, Vol 88, No 3, pp 179-186
  5. Kim. Y.B. (1999). "A Study on Robustness of a Two-Degree-of-Freedom Servo System with Nomlinear Type Uncertainty(II)-Robust Stabillity Condition", Int, J. of KCORE, Vol 13, No 3-II, pp 99-105
  6. Kim. Y.B. Byun. J.H. and Yang. J.H. (2001). "Synchronous Control of a Tow-Axes Drving System by Disurbance Observer and PID Controller", Int. J. of KCOPE, Vol 15, No 1, pp, 67-72
  7. Onoda, J. and Haftka, R.T. (1987). "An Approach to Structure/Control Simultaneous Optimization for Jarge Flexible Spacecraft", J. of AIAA, Vol 25, No 8, pp 1133-1138 https://doi.org/10.2514/3.9754
  8. Rao. S.S. (1990). "Robustness Improvement of Actively Controlled Structures through Structural Modifications", J. of AIAA, Vol 28, No 2, pp. 353-361 https://doi.org/10.2514/3.10396
  9. Salama, M. (1988). "Simultaneous Optimization of Controlled Structures", J. of the Computational Mechanics, Vol 88, No 3, pp. 275-282
  10. Tada, Y. and Park J.H. (1999). "Combined Design of Structural and Control Systems(Representation by Descriptor System Rorms and Use of LMI)", Trans. of JSME, Vol 65, No 636, pp 3155-3160 https://doi.org/10.1299/kikaic.65.3155
  11. Tada, Y. and Park. J.H. (2000). "Simultaneous Optimal Design of Structural and Control Systems for Flexible Structure (Representation by Descriptor System Forms)", Trans. of ISCIE, Vol 13, No 1, pp 14-19 https://doi.org/10.5687/iscie.13.14