Distributed adaptive synchronization for multiple spacecraft formation flying around Lagrange point orbits

Solar sail cooperative formation flying around L2-type artificial equilibrium points

“…To this end, paralleling the procedure described in Ref. [63], a Fourier series-based solution with a least-square technique is now proposed to estimate the nominal trajectory with a reduced computational effort. The nominal trajectory is represented with an approximate trigonometric polynomial as…”

“…According to the procedure discussed in Ref. [63], a few pertinent concepts of algebraic graph theory [66] are first briefly summarized for the sake of completeness. A directed graph G consists of a finite non-empty vertex set V {υ 1 , .…”

Time-Optimal Formation Establishment Around a Slowly Rotating Asteroid

“…When multiple spacecraft operate in close proximity, a (virtual) synthetic aperture radar can be ideally assembled [16] to improve the resolution of stereoscopic images, with a substantial reduction of the overall mission cost. In this scenario, the consensus concept guarantees a functional module distribution among the spacecraft in the formation [17,18], in such a way as to eliminate the inherent single point of failure of the on-board system [19,20].…”

Disturbance observer based finite-time coordinated attitude tracking control for spacecraft on SO(3)

“…Considering the adverse effect on SFF caused by the external disturbance, a majority of methods have been proposed for the attitude synchronization and tracking control problem, involving back-stepping control [13−15], adaptive control [16−18], sliding mode control [19−21], event-triggered control [22−24] and disturbance observer based control [10,25,26]. Back-stepping based control strategies possess satisfactory ability for disturbance rejection via combining other methods, such as sliding mode control [13] and adaptive control [15]. Nevertheless, the drawback of "explosion of complexity " caused by repeated derivative on the virtual command must be accounted during space missions.…”

“…However, the conventional back-stepping method has limitations for a class of nonlinear systems, namely the complexity explosion problem. To improve the methods proposed in [13] and [15], the command filter is utilized in the back-stepping procedure in this paper, thereby realizing the attitude containment objective when there exists external disturbance. Compared with the back-stepping based control, the sliding mode control technology possesses satisfactory capability of disturbance attenuation, which brings about fruitful research results [19−21].…”