179 analysis 14 yields the bounds ° max¸°¸° min where, to rst order in the small ±, Again, these quantities will be more sensitive if the moments of inertia are close than if they are widely spaced. For a vehicle with nominal inertias satisfying I 1 D 2I 3 and I 2 D 1:5I 3 , and the 1% normalized inertia perturbations considered earlier, arctan ° can vary… (More)
For a large Adaptive Optics (AO) system such as a large Segmented Mirror Telescope (SMT), it is often difficult, although not impossible, to directly apply common Multi-Input Multi-Output (MIMO) controller design methods due to the computational burden imposed by the large dimension of the system model. In this paper, a practical controller design method is… (More)
A comparative study of the robustness of various spacecraft body attitude control systems with structural flexibility is presented in this paper. The control systems examined are: (a) 3-Reaction Wheels (b) Body-fixed momentum wheel with offset thrusters (c) Skewed body-fixed momentum wheels with offset thrusters and (d) Body-fixed momentum wheel with two… (More)
This paper presents experimental results of vibration suppression of a ¯exible structure using smart materials and a miniaturized digital controller, called the modular control patch (MCP). The MCP employs a TI-C30 digital signal processor and was developed by TRW for the United States Air Force for future space vibration control. In this research, the MCP… (More)
Theme T HIS paper concerns the effects of inequalities in the transverse inertias and stiffnesses of the flexible joint of a dual-spin spacecraft on its stability and nutation frequency.
Inflatable structures are effective in space applications, as they are weight, volume and cost competitive. For certain space applications, higher gains are obtained for the antennas by increasing their size. Higher gains often result in increased data throughput. These and other advantages lead to inflatable structures being considered increasingly for… (More)