Torque-saturated, Inertia-free Spacecraft Attitude Control
نویسندگان
چکیده
Torque-saturated control laws for spacecraft attitude control are considered. These control laws require no knowledge of the mass distribution of the spacecraft and thus are inertia-free. We examine two specific problems. In the first problem, the spacecraft has an arbitrary initial attitude and angular velocity, and the objective is to bring the spacecraft to rest with a specified attitude. In the second problem, the spacecraft has an arbitrary initial attitude and angular velocity, and the objective is to bring the spacecraft to a spin about a specified body axis with a specified attitude. The body axis need not be a principal axis. Both problems are considered under the assumption that the torque, which is continuously variable, is limited by a saturation constraint. Disturbances are assumed to be zero.
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