Linear Parameter Varying Steering Law for Control Moment Gyros
DEI PhD Student
DEI - Aula 3B
10 Novembre 2011
Controlling the attitude of spacecraft is an important challenge from both a theoretical and a practical point of view. Even if many works are devoted to this issue, this research field presents several aspects which have been partially explored and are worth pointing out. This project aims at the development of effective control techniques for spacecraft attitude based on the use of Control Moment Gyros (CMGs) mounted on the spacecraft in a pyramid configuration. This physical layout allows the control system designer to induce large torques along the x-y-z axes of the spacecraft by independently manipulating the spin axis of the reaction wheel of each gyroscope. Unfortunately, the gimbal motions can lead to relative orientations (singularities) that produce no usable output torque along certain directions: the control techniques for CMGs (steering laws) have to take into account this phenomenon in order to avoid the occurrence of these singularities. This research aims to study the recently proposed control strategy for spacecraft attitude equipped with CMGs, to develop singularity avoidance control law for these systems and to assess their performance and limitations in a realistic case study. In particular we exploit an alternative LPV based steering law which theoretically stabilizes the feedback system guaranteeing the desired performances in terms of induced L2 norm.
Area di ricerca:
Controllo, automazione e misure