A Numerical Comparison of Inertia-Free Attitude Control Laws for a Spacecraft with a Discrete Flexible Mode
نویسندگان
چکیده
Structural flexibility in spacecraft can degrade the accuracy of the attitude control system. With this motivation in mind, we compare the performance of inertia-free attitude control laws for a spacecraft with an undamped discrete flexible mode and demonstrate robustness with respect to unmodeled spacecraft dynamics and actuator saturation. First the equations of motion are derived using Lagrangian dynamics. Next we present the inertia-free control laws considered in the study. Next, we establish a baseline model for subsequent comparisons. Finally, we demonstrate robustness of the control laws to actuator saturation and plant uncertainty through variations in the inertia matrix as well as the parameters of the discrete flexible mode.
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