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The dynamics and control of large flexible space structures - 12, supplement 11
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Reddy, A. S. S. R. Xu, Jianke Li, Feiyue Bainum, Peter M. |
| Copyright Year | 1989 |
| Description | The rapid 2-D slewing and vibrational control of the unsymmetrical flexible SCOLE (Spacecraft Control Laboratory Experiment) with multi-bounded controls is considered. Pontryagin's Maximum Principle is applied to the nonlinear equations of the system to derive the necessary conditions for the optimal control. The resulting two point boundary value problem is then solved by using the quasilinearization technique, and the near minimum time is obtained by sequentially shortening the slewing time until the controls are near the bang-bang type. The tradeoff between the minimum time and the minimum flexible amplitude requirements is discussed. The numerical results show that the responses of the nonlinear system are significantly different from those of the linearized system for rapid slewing. The SCOLE station-keeping closed loop dynamics are re-examined by employing a slightly different method for developing the equations of motion in which higher order terms in the expressions for the mast modal shape functions are now included. A preliminary study on the effect of actuator mass on the closed loop dynamics of large space systems is conducted. A numerical example based on a coupled two-mass two-spring system illustrates the effect of changes caused in the mass and stiffness matrices on the closed loop system eigenvalues. In certain cases the need for redesigning control laws previously synthesized, but not accounting for actuator masses, is indicated. |
| File Size | 1750577 |
| Page Count | 67 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19900004178 |
| Archival Resource Key | ark:/13960/t7gr1t93f |
| Language | English |
| Publisher Date | 1989-09-01 |
| Access Restriction | Open |
| Subject Keyword | Spacecraft Design, Testing And Performance Slewing Stiffness Matrix Actuators Boundary Value Problems Flexible Spacecraft Feedback Control Shape Control Vibration Damping Optimal Control Spacecraft Control Spacecraft Stability Control Theory Linearization Large Space Structures Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
