Set Of Attitude Parameters Research Articles

New Set of Attitude Parameters Dedicated to Relative Attitude Maneuvers

A new set of attitude parameters that minimize the eigenangle between a body-fixed frame and a target reference frame was developed for application to rapid attitude maneuver of a spacecraft. The target reference frame is defined by using the pointing vector from the spacecraft to the target. Attitude kinematics based on the new set of attitude parameters is subsequently derived. To accomplish fast attitude maneuver, a cascade-saturation controller is then designed based on the proposed attitude parameters. The constraints of slew rate and control torque are considered in the proposed cascade-saturation controller. The stability of the resulting closed-loop system is proved by the Lyapunov theory. Simulation results verify that the proposed parameters are well-suited for spacecraft rapid target acquisition and tracking control.

Spacecraft angular velocity trajectory planning for SGCMG singularity avoidance

A trajectory planning method for angular velocity of spacecraft is developed to avoid the impassable singular states for singular gimbal control moment gyroscope (SGCMG) systems in this paper. A new set of attitude parameters, named σ-parameters, is first developed. Based on the properties of σ-parameters, two approximate decoupled rotations are presented. To achieve a rapid attitude maneuver, both of the decoupled motions are designed as simple bang-off-bang type maneuvers. Then, a type of SGCMG singularity-free angular velocity trajectory on the conic surface is developed. Thereafter, an attitude controller based on σ-parameters is developed to track the reference trajectory. To avoid the impassable singular state, suitable axes of the approximate decoupled two rotations are chosen to achieve the fastest maneuver under the condition that the minimum distance from the angular momentum trajectory to the impassable surface is greater than a safety distance. Finally, simulations are performed to verify the effectiveness of the proposed SGCMG singularity avoidance method.

Attitude Determination for Satellites in the INTERBALL Project from a Limited Set of Measurements

The determination of the orientation of satellites in the INTERBALL project from a limited set of measurements is discussed. It is shown that the full set of attitude parameters can be obtained by processing only the solar sensor data. The accuracy of corresponding parameters is estimated from alternative measurements.