Solar sail attitude control through in-plane moving masses

Abstract

A three-axis solar sail attitude control system for interplanetary missions is proposed: required steering is achieved by means of a small control mass in the solar sail plane, whereas roll-axis control is achieved through the rotation of ballast with two masses at the extremities. The satellite is fixed at the sail geometrical centre: this solution avoids the difficulties arising from the employment of an out-of-plane control boom with the satellite at the end, i.e. pointing problems for optical payloads and communication antennas. A circular sailcraft of 220 kg with characteristic acceleration a(c) = 0.5 mm/s(2) is considered, and the control system performances are presented in terms of pointing accuracy for a rendezvous mission to Mercury. The dynamical model takes into account the perturbation torque because of an offset between the centre of pressure and the geometrical sail centre, as well as the Sun gravity-gradient effect and a perturbation torque on the roll axis

Dynamic and Structural Performances of a New Sailcraft Concept for Interplanetary Missions

“…A 35-degree manoeuvre is taken into account to compare these performances with literature data. Note that, due to slow dynamics, classical interplanetary missions require small-amplitude manoeuvres per day [ 37 , 38 ], while a fast manoeuvre is required only for “nonclassical” interplanetary missions [ 39 , 40 ]. A body reference frame is considered for modelling sailcraft attitude dynamics, as described in Section 2 .…”

A Linear Photonic Thrust Model and its Application to the L'Garde Solar Sail Surface

“…Examples include the recent study of the mm-scale "Sprite" sailcraft by Atchinson [18] (where the thrust coefficient used corresponds to η=1.7 in the present nomenclature); Bolle's work on sail attitude control methodology [19] (with η=1.8), and Circi's study of regular spacecraft attitude control augmented with sail elements [20].…”

Nonlinear Controller Design for a Flexible Spacecraft

“…Examples of cases where large structures have been modeled as rigid bodies can be found in [16] and [23]. In [15] and [3], even though rigid dynamics are used, the potential influence of the coupling between natural frequencies and external or internal disturbances is pointed out. This coupling is studied for two particular controllers over a large solar sail in [18].…”