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)
A Satellite Attitude Dynamics Simulator (SADS) has been developed to facilitate the research and development of spacecraft flight attitude control software at the Naval Postgraduate School in Monterey, CA. The simulator provides a real-time 3 degree of freedom (3DOF) synthetic spacecraft hardware-in-the-loop environment, that includes realistic angular… (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)
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 discusses two optical beam control testbeds developed at the Spacecraft Research and Design Center, Naval Postgraduate School, to evaluate and develop control techniques for jitter and adaptive optics control. The first testbed, a Jitter Control Testbed is used to develop control techniques for optical beam jitter. In the second testbed, the… (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.
This paper presents active surface control techniques for space mirrors. These techniques use adaptive optics concepts for correcting aberration in images due to air turbulence. Due to mirror surface error, a reference beam can be distorted and this error is measured by a wavefront sensor. A control system is used to provide input to the actuators based on… (More)