19,116 research outputs found
Attitude and Phase Synchronization of Formation Flying Spacecraft: Lagrangian Approach
This article presents a unified synchronization framework with application to precision formation flying spacecraft. Central to the proposed innovation, in applying synchroniza-
tion to both translational and rotational dynamics in the Lagrangian form, is the use of the distributed stability and performance analysis tool, called contraction analysis that yields exact nonlinear stability proofs. The proposed decentralized tracking control law synchronizes the attitude of an arbitrary number of spacecraft into a common time-varying trajectory with global exponential convergence. Moreover, a decentralized translational tracking control law based on phase synchronization is presented, thus enabling coupled translational and rotational maneuvers. While the translational dynamics can be adequately controlled by linear control laws, the proposed method permits highly nonlinear systems with nonlinearly coupled inertia matrices such as the attitude dynamics of space-craft whose large and rapid slew maneuvers justify the nonlinear control approach. The
proposed method integrates both the trajectory tracking and synchronization problems in a single control framework
Synchronization with partial state feedback on SO(n),
peer reviewedThis paper considers the problem of constructing a distributed feedback law to achieve synchronization for a group of k agents whose states evolve on SO(n) and which exchange only partial state information along communication links. The partial state information is given by the action of the state on reference vectors
in Rn. We propose a gradient based control law which achieves exponential local convergence to a synchronization configuration under a rank condition on a generalized Laplacian matrix. Furthermore, we discuss the case of time-varying reference vectors and provide a convergence result for this case. The latter helps reach synchronization, requiring less communication links and weaker conditions on the instantaneous reference vectors. Our methods are illustrated on an attitude synchronization problem where agents exchange only their relative positions observed in the respective body frames
Application of Synchronization to Formation Flying Spacecraft: Lagrangian Approach
This paper presents a unified synchronization framework with application to precision formation flying
spacecraft. Central to the proposed innovation, in applying synchronization to both translational and rotational
dynamics in the Lagrangian form, is the use of the distributed stability and performance analysis tool, called
contraction analysis that yields exact nonlinear stability proofs. The proposed decentralized tracking control law
synchronizes the attitude of an arbitrary number of spacecraft into a common time-varying trajectory with global
exponential convergence. Moreover, a decentralized translational tracking control law based on oscillator phase
synchronization is presented, thus enabling coupled translational and rotational maneuvers. Although the
translational dynamics can be adequately controlled by linear control laws, the proposed method permits highly
nonlinear systems with nonlinearly coupled inertia matrices such as the attitude dynamics of spacecraft whose large
and rapid slew maneuvers justify the nonlinear control approach. The proposed method integrates both the
trajectory tracking and synchronization problems in a single control framework
A distributed attitude control law for formation flying based on the Cucker-smale model
In this paper we consider the attitude synchronization problem for a swarm of spacecrafts flying in formation.
Starting from previous works on consensus dynamics, we construct a distributed attitude control law and derive analytically
sufficient conditions for the formation to converge asymptotically towards a synchronized, non–accelerating state (possibly defined a priori). Moreover, motivated by the results obtained on a particular consensus model, first introduced by F. Cucker and S. Smale to modellize the translational dynamics of flocks, we numerically explore
the dependence of the convergence process on the dimension of the formation and the relative initial conditions of the spacecrafts. Finally, we generalize the class of weights defined by the previous authors in order to dampen the aforementioned effects, thus making our control law suitable for very large formations.Postprint (published version
Distributed Adaptive Attitude Synchronization of Multiple Spacecraft
This paper addresses the distributed attitude synchronization problem of
multiple spacecraft with unknown inertia matrices. Two distributed adaptive
controllers are proposed for the cases with and without a virtual leader to
which a time-varying reference attitude is assigned. The first controller
achieves attitude synchronization for a group of spacecraft with a leaderless
communication topology having a directed spanning tree. The second controller
guarantees that all spacecraft track the reference attitude if the virtual
leader has a directed path to all other spacecraft. Simulation examples are
presented to illustrate the effectiveness of the results.Comment: 13 pages, 11 figures. To appear in SCIENCE CHINA Technological
Science
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