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provides a comprehensive introduction to two important disciplines indispensable in the design of spacecraft and aeronautical structures: Engineering Mechanics and Control Engineering. The rationale behind their novel unified approach in teaching dynamical modeling, analysis, and control design for flexible structures, according to the authors, is that "effective control laws for mechanical systems are best designed by one who understands both the basic mechanics of the system under consideration and the control methodology being used to design the control law." A better understanding of the interface between these two disciplines is indeed the crucial development needed to better designs for actively controlled aerospace structures. The authors have clearly provided an outstanding text to strengthen this important interface for practicing engineers and students of aeronautical/astronautical engineering.The text starts with a review of essential mathematical preliminaries which consists of an efficient review of computational linear algebra. Also included in this discussion and throughout the text, are numerous applications of the authors' MATLAB operators. The MATLAB operators, used to do the computational examples in the text, provide an excellent supplement of the text, but their detailed discussion is relegated to an appendix and the documentation on the diskette itself. The mathematical preliminaries are followed by chapters on Lyapunov stability theory and application, and mathematical models for the dynamics of structural systems, represented both by systems of partial differential equations and systems of ordinary differential equations obtained by using the finite element method. The final three chapters deal with analysis and design of linear feedback controllers for structural systems. Each of these chapters provide excellent introductions to basic concepts for the design of control laws for flexible structures subjected to dynamic loading. While these chapters are tutorial, significant new material from recent research has been integrated throughout.The AIAA Education Series embraces a broad spectrum of theory and application of different disciplines in aerospace, including aerospace design practice. The Series has now been expanded to include defense science, engineering, and technology. The basic philosophy for the Series is to develop both teaching texts for students and reference materials for practicing engineers and scientists. PREFACEThis text is the outgrowth of our work over the past decade on the interface of the two traditional disciplines: Engineering Mechanics and Control Engineering. Our work has been an interesting mixture of theoretical, computational, laboratory experimental, and applications to aerospace vehicle dynamics and control. From this range of basic and applied research, along with our teaching activities, a perspective has evolved which is reflected throughout this text.The kernel of our viewpoint is that effective control laws for mechanical systems are best designed by on...

In this paper a novel approach is developed for relative navigation and attitude estimation of spacecraft flying in formation. The approach uses information from an optical sensor, which employs relatively simple electronic circuits with modest digital signal processing requirements, to provide multiple line-of-sight vectors from spacecraft to another. The sensor mechanism is well suited for both near-Earth and deep space applications since it is fully independent of any external systems. The line-of-sight measurements are coupled with gyro measurements and dynamical models in an extended Kalman filter to determine relative attitude, position and gyro biases. The quaternion is used to describe the relative kinematics and general relative orbital equations are used to describe the positional dynamics. Simulation results indicate that the combined sensor/estimator approach provides accurate relative position and attitude estimates.

An output feedback structured model reference adaptive control law has been developed for spacecraft rendezvous and docking problems. The effect of bounded output errors on controller performance is studied in detail. Output errors can represent an aggregation of sensor calibration errors, systematic bias, or some stochastic disturbances present in any real sensor measurements or state estimates. The performance of the control laws for stable, bounded tracking of the relative position and attitude trajectories is evaluated, considering unmodeled external as well as parametric disturbances and realistic position and attitude measurement errors. Essential ideas and results from computer simulations are presented to illustrate the performance of the algorithm developed in the paper.