AstroNet-II

The Astrodynamics Network

Research themes

The scientific programme focuses on a number of key astrodynamical objectives of current interest to space agencies and industry. However, they are also of considerable mathematical interest, both as application of current and elaborated theoretical concepts and numerical methods, and as problem sources, motivation and inspiration for the development of new mathematics. Furthermore, it is our belief that the interface of mathematics and astrodynamics provides an exciting research arena from the point of view of both the applications and the mathematics itself.

The Scientific Programme is divided into three sections:

I.    Trajectory Design and Control,
II.   Attitude Control and Structural Flexibility of Spacecraft, and
III.  Formation Flying.

I. Trajectory Design and Control

The overall aim of this section is to study models that can be used to design energy efficient spacecraft trajectories. The underlying philosophy is always to exploit the natural dynamics of a spacecraft moving in the solar system.

Particular items of this section are:

I.1  Invariant Manifold Dynamics,
I.2  Low Thrust Non-Keplerian Orbits,
I.3  Coupled Attitude-Orbit Dynamics, and
I.4  Asteroid and Binary Asteroids Missions.

II. Attitude Control and Structural Flexibility of Spacecraft

The current spacecraft attitude control algorithms make little use of recent advances such as geometric mechanics, control theory and complexity science. Where mathematical theory is used it is largely confined to over-actuated systems and does not take into account the very limited resources available to micro-spacecraft. In addition to this, the requirement that control algorithms need to minimize either the time taken to complete a manoeuvre, or the fuel used, leads to new geometric optimisation problems. The overall aim of this section is to develop, analyse and test mathematical models and algorithms for a variety of different attitude control mechanisms.

Particular items of this section are:

II.1  Optimal and Feasible Attitude Motions for Micro-Spacecraft,
II.2  Modelling and Attitude Control of 'Flexible' Spacecraft, and
II.3  Dissipative Effects on Attitude Dynamics.

III. Formation Flying

The degree of precision required for formation flying missions is a scientific challenge that requires a high level of mathematical input in the development of the algorithms. Although there has been research for formation reconfiguration and manoeuvring in free space, there has been a limited amount of research into manoeuvring without collisions and in other enviroments. Furthermore, none of the research work to-date has looked at fully decoupling the relative motion and exploiting the natural dynamics of the suitable models to ensure safe formation reconfiguration.

Particular items of this section are:

III.1 Transfers, Deployment and Proximity Manoeuvring for Multiple Spacecraft,
III.2 Formation Flying Using Low Thrust Propulsion, and
III.3 Space Inspection and Autonomy.