Combined design of structures and controllers for optimal maneuverability
- 60 Downloads
- 4 Citations
Abstract
This paper treats the problem of the combined design of structure/control systems for achieving optimal maneuverability. A maneuverability index which directly reflects the time required to perform a given maneuver or set of maneuvers is introduced. By designing the flexible appendages of a spacecraft, its maneuverability is optimized under the constraints of structural properties, and of the postmaneuver spill-over being within a specified bound. The spillover reduction is achieved by making use of an appropriate control design model. The distributed parameter design problem is approached using assumed shape functions and finite element analysis with dynamic reduction. Characteristics of the problem and problem solving procedures have been investigated. Adaptive approximate design methods have been developed to overcome computational difficulties. It is shown that the global optimal design may be obtained by tuning the natural frequencies of the spacecraft to satisfy specific constraints. We quantify the difference between a lower bound to the objective function associated with the original problem and the estimate obtained from the modified problem as the index for the adaptive refinement procedure. Numerical examples show that the results of the optimal design can provide substantial improvement.
Keywords
Finite Element Analysis Optimal Design Shape Function Design Model Refinement ProcedurePreview
Unable to display preview. Download preview PDF.
References
- Athanas, M.; Falb, P. 1966:Optimal control. New York: MacGraw-HillGoogle Scholar
- Barbieri, E.; Ozguner, U. 1988: Rest-to-rest slewing of flexible structures in minimum time.Proc. IEEE Conf. Decision and Control (held in Austin, TX), pp. 1633–1638Google Scholar
- Ben-Asher, J.; Burns, J.A.; Cliff, E.M. 1987: Time optimal slewing of flexible spacecraft.Proc. IEEE Conf. Decision and Control (held in Los Angeles, CA), pp. 524–528Google Scholar
- Bendsøe, M.P; Olhoff, N.; Taylor, J.E. 1987: On the design of structure and controls for optimal performance of actively controlled flexible structures.Mech. Struct. & Mach. 51, 265–295Google Scholar
- Bodden, D.S.; Junkins, J.L. 1985: Eigenvalue optimization algorithms for structure/controller design iterations.J. Guidance, Control and Dynamics 8, 697–706Google Scholar
- Breakwell, J.A. 1981: Optimal feedback slewing of flexible spacecraft.J. Guidance, Control and Dynamics 4, 472–479Google Scholar
- Doyle, J.C. 1987: Guaranteed margins for LQG regulators.IEEE Trans. Auto. Control AC-23, 756–757Google Scholar
- Doyle, J.C.; Stein, G. 1979: Robustness with observer.IEEE Trans. Auto. Control AC-24, 607–611Google Scholar
- Fetterman, T.L.; Noor, A.K. 1987: Computational procedures for evaluating the sensitivity derivatives of vibration frequencies and eigenmodes of framed structures.NASA Contractor Report 4099 Google Scholar
- Fujii, H.; Ishijima, S. 1989: Mission-function control for slew maneuver of a flexible space structure.J. Guidance, Control and Dynamics 12, 858–865Google Scholar
- Garcia, C.B.; Zangwill, W.I. 1981:Pathways to solutions, fixed points and equilibria. New Jersey: Prentice-HallGoogle Scholar
- Haftka, R.T.; Kamat, M.P. 1985:Elements of optimal structural design. Dordrecht: KluwerGoogle Scholar
- Haftka, R.T.; Martinovic Z.N.; Hallauer, W.L. Jr. 1985: Enhanced vibration controllability by minor structural modification.AIAA J. 23, 1260–1266Google Scholar
- Hale, A.L.; Lisowski, R.J. 1985: Characteristic elastic systems of time-limited optimal maneuvers.J. Guidance, Control and Dynamics 8, 628–636Google Scholar
- Hale, A.L.; Lisowski, R.J.: Optimal simultaneous structural and control design of maneuvering flexible spacecraft.Proc. 4th VPI & SU/AIAA Google Scholar
- Hale, A.L.; Lisowski, R.J.; Dahl, W.E. 1984: Optimal simultaneous structural and control design of maneuvering flexible spacecraft.J. Guidance, Control and Dynamics 8, 86–93Google Scholar
- Hartman, P. 1982:Ordinary differential equations. Boston: BirkhauserGoogle Scholar
- Khot, N.S. 1988: An integrated approach to the minimum weight and optimum control design of space structures. In:Large space structures: dynamics and control, pp. 355–363. Berlin, Heidelberg, New York: SpringerGoogle Scholar
- Khot, N.S.; Eastep, F.E.; Venkayya, V.B. 1985a: Optimal structural modifications to enhance the optimal active vibration control of large flexible structures.AIAA Paper, 85-0627Google Scholar
- Khot, N.S.; Eastep, F.E.; Venkayya, V.B. 1985b: Simultaneous optimal structural/control modifications to enhance the vibration control of large of a large flexible structure.AIAA Paper, 85-1925Google Scholar
- Khot, N.S.; Oz, H.; Grandhi, R.V.; Eastep, F.E.; Venkayya, V.B. 1988: Optimal structural design with control gain norm constraint.AIAA J. 26, 604–611Google Scholar
- Lehtomaki, N.A.; Sandell, N.R.; Athanas, M. 1981: Robustness results in linear quadratic Gaussian based multivariable control design.IEEE Trans. Auto. Control AC-26, 75–93Google Scholar
- Lim, K.B.; Junkins, J.L. 1989: Robustness optimization of structural and controller parameters.J. Guidance, Control and Dynamics 12, 89–96Google Scholar
- Luenberger, D.G. 1984:Linear and nonlinear programming. New York: Addison-WesleyGoogle Scholar
- Lust, R.V.; Schmit, L.A. 1988: Control-augmented structural synthesis.AIAA J. 26, 86–95Google Scholar
- Meirovitch, L. 1967:Analytical methods in vibrations. New York: MacMillanGoogle Scholar
- Onoda, J.; Haftka, R.T. 1987: An aproach to structural/control simultaneous optimization for large flexible spacecraft.AIAA J. 25, 1133–1138Google Scholar
- Safanov, M.G.; Athanas, M. 1977: Gain and phase margin for multiloop LQG regulators.IEEE Trans. Auto. Control AC-22, 173–179Google Scholar
- Singh, G.; Kabamba, P.T.; McClamroch, N.H. 1989: Planar, time-optimal, rest-to-rest slewing maneuvers of flexible spacecraft.J. Guidance, Control and Dynamics 12, 71–81Google Scholar
- Thompson, R.C.; Junkins, J.L.; Vadali S.R. 1989: Near-minimum time open-loop slewing of flexible vehicles.J. Guidance, Control and Dynamics 12, 82–88Google Scholar
- Thompson, R.C.; Junkins, J.L.; Vadali S.R. 1990: Near-minimum time close-loop slewing of flexible spacecraft.J. Guidance, Control and Dynamics 13, 57–65Google Scholar
- Turner, J.D.; Chun, H.M. 1984: Optimal distributed control of flexible spacecraft during a large-angle maneuver.J. Guidance, Control and Dynamics 7, 257–264Google Scholar
- Vadali, S.R. 1986: Variable-structure control of spacecraft largeangle maneuvers.J. Guidance, Control and Dynamics 9, 235–239Google Scholar
- Van der Velde, W.E.; He, J. 1983: Design of space structure control systems using on-off thrusters.J. Guidance, Control and Dynamcis 6, 53–60Google Scholar