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An attitude control strategy for gossamer spacecraft is proposed, where control torques are generated by an electrically conducting support structure interacting with the Earth’s magnetic field. A mathematical model of the structure is developed, where the overall torque is found by summation of the Lorentz forces acting upon each current-carrying structural element. Different geometric configurations are shown to allow effective magnetic dipole moments in three orthogonal directions. With this model, the results of dynamic simulation are presented in order to assess the ability of the conducting structure to detumble itself in-orbit, using the classical Bdot control law. The possibility of using this attitude control system to manoeuvre orbital reflectors is then investigated. The required angular accelerations for a large solar reflector in polar orbit to continuously illuminate a fixed point on the Earth’s surface are derived within a simplified model, and compared with those achievable by the conducting structure. Simulation is then used to assess whether the conducting structure is capable of achieving partial attitude control of an orbital reflector, for example to illuminate terrestrial solar power farms at dawn and dusk when their output is low.

The acquisition of samples from deep within planets, moons and asteroids will require a drilling and sample-retrieving system. A prototype of such a system has been trialled in a partial analogue environment, resulting in the successful extraction of core samples from a range of rocks including sandstone, vesicular basalt and pumice using a mobile rover testbed. This paper describes the mechanical design, software and systems engineering associated with the drill tool, the performances of the hardware, and the nature of the holes.

A deployment system for a CubeSat-compatible aerobrake is set out. The dynamic behavior of tape-springs wound a round a central hub is described and some of the developmental challenges in developing such a system, such as managing the rotation of the spool to prevent blooming, are discussed. The deployment rates of several systems are presented and the overall concept is shown to achieve deployment of a 1m2 drag sail for a mass of 372g and vertical dimension of around 0.4U. Finally, developments required to most fully realize some alternative applications. such as antenna structures and solar sailing, are considered.

Variable geometry solar sailing potentially offers enhanced delta-V capabilities and new orbital solutions. We propose a device with such capabilities, based upon an adjustable quasi-rhombic pyramid sail geometry, and examine the benefits that can be derived from this additional flexibility. The enabling technology for this concept is the bevel crux drive, which can maintain tension in the solar sail across a wide range of apex angles. This paper explores the concept of such a device, discussing both the capabilities of the architecture and the possibilities opened up in terms of orbital and attitude dynamics.