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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.

In the last few years interest in versatile reconfigurable arrays for space applications has been growing and several concepts tailored for different mission needs have been proposed. Nevertheless, a compelling application that justifies their higher cost and complexity with respect to conventional systems has not yet been found. Here a novel approach to the design of an Attitude Control System (ACS) for small reconfigurable spacecraft is proposed. It shall exploit momentum-preserving internal torques generated by the modules of the multibody array rotating relative to each other. The goal is to achieve better performance in efficiency, accuracy and robustness with respect to state-of-the-art ACSs, which is a bottleneck of small spacecraft technology. This paper investigates the characteristic behaviour of a planar multibody array whose attitude is controlled using internal joint torques. To do this, relevant reorientation trajectories are shown and discussed. With respect to previous work in the field, optimal attitude control trajectories that take into account module impingement are discussed and the dynamics of momentum-preserving manoeuvres is explained in detail from both physical and mathematical points of view. The results demonstrate that further development of the concept is desirable.

Femto-satellites have attracted growing attention over the past few years, with various universities taking up the challenge declared by the N-Prize. Many novel designs have been proposed, some of which are equipped with active attitude control based on either magnetic or electro-chromic control systems. However, conventional test platforms are unsuitable for testing control systems on such small length-scales and as such, developing suitable test platforms to be used for testing femto-satellite attitude control algorithms becomes important. This paper proposes six different concepts of laboratory-scale test platforms for femto-satellite attitude control testing, based on various physical laws. These platforms are manufactured using SLA 3D printing technology and then assembled. Qualitative observations are recorded and an experimental setup is devised in order to quantify the total resistive torque that appears in each platform. Results show that two of the designs display a maximum resistive torque on the order of 10^(-6) when spinning very rapidly, decreasing to the order of 10^(-7) at low angular velocities, which makes these designs suitable for their intended purpose. Finally, future work is proposed towards assessing the suitability of the other four platforms.

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.

This paper describes a preliminary design study to assess the possibility of flying a wideband ionospheric sounder cubesat experiment (WISCER). WISCER comprises a wideband (∼100 MHz) beacon on a low cost cubesat designed to measure and evaluate the ionospheric channel in anticipation of the development of operational, space-based, low frequency (i.e. around 450MHz) synthetic aperture radar (SAR) systems.

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.

Over the last three years the authors have been involved in three experiments that were or will be launched on sounding rockets and high altitude balloons with the REXUS/BEXUS program (Rocket-borne / Balloon-borne Experiments for University Students). The first experiment, called Suaineadh was launched from Esrange (Kiruna, Sweden) onboard REXUS 12 in March 2012. Suaineadh had the purpose of deploying a web in space by using centrifugal forces. The payload was lost during re-entry but was recovered 18 month later in early September 2013. StrathSat-R is the second experiment, which had the purpose of deploying two cube satellites with inflatable structures from the REXUS 13 sounding rocket, was launched first in May 2013 and will be launched a second time in spring 2014. The last experiment is the iSEDE experiment which has the goal of deploying an inflatable structure with disaggregated electronics from the high altitude balloon BEXUS15/16 in October 2013. All these experiments have been designed, built and flown in a timeframe of one and a half to two years. This paper will present the lessons learned in project management, outreach, experiment design, fabrication and manufacturing, software design and implementation, testing and validation as well as launch, flight and post-flight. Furthermore, the lessons learned during the recovery mission of Suaineadh will be discussed as well. All these experiments were designed, built and tested by a large group of university students of various disciplines and different nationalities. StrathSat-R and iSEDE were built completely at Strathclyde but the Suaineadh experiment was a joint project between Glasgow and Stockholm which was especially tricky during integration while approaching the experiment delivery deadline. This paper should help students and professionals across various disciplines to build and organise these kinds of projects more efficiently without making the same, sometimes expensive, mistakes all over again.