Nonlinear Predictive Controller For Attitude Control And Momentum Management Of A Space Station

The objective of this research is to use the H[subscript infinity] optimality criterion to design a controller for the linearized set of Space Station dynamics equations. Besides studying the various closed-loop properties of the resulting linear system, we would like to examine the robustness properties of this controller i.e. how well it performs in the presence of unmodelled dynamics, non-linearities and disturbances. Furthermore, we will compare and contrast the control action of the H[subscript infinity] controller with that of the LQR controller."

Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS)* at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dis semination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volumes were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 39 (thesis year 1994) a total of 13,953 thesis titles from 21 Canadian and 159 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this impor tant annual reference work. While Volume 39 reports theses submitted in 1994, on occasion, certain uni versities do report theses submitted in previous years but not reported at the time.

The design and evaluation of an attitude control/momentum management system for highly asymmetric spacecraft configurations are presented. The preliminary development and application of a nonlinear control system design methodology for tracking control of uncertain systems, such as spacecraft payload pointing systems are also presented. Control issues relevant to both linear and nonlinear rigid-body spacecraft dynamics are addressed, whereas any structural flexibilities are not taken into consideration. Results from the first task indicate that certain commonly used simplifications in the equations of motions result in unstable attitude control systems, when used for highly asymmetric spacecraft configurations. An approach is suggested circumventing this problem. Additionally, even though preliminary results from the second task are encouraging, the proposed nonlinear control system design method requires further investigation prior to its application and use as an effective payload pointing system design technique. Parlos, Alexander G. and Jayasuriya, Suhada Unspecified Center ATTITUDE CONTROL; CONTROL SYSTEMS DESIGN; MANAGEMENT SYSTEMS; MOMENTUM; POINTING CONTROL SYSTEMS; RIGID STRUCTURES; SPACECRAFT CONTROL; ASYMMETRY; EQUATIONS OF MOTION; NONLINEAR SYSTEMS; SPACECRAFT CONFIGURATIONS...