In the last decades, the growing interest in investigating natural science in the space environment sets new targets, constraints and challenges in space mission design, defining what is nowadays known as space science. The goal of this PhD research is the development of new techniques of mission analysis, which can lead to further development of space science missions using CubeSat technology. Two main objectives have been pursued, related to both solar system exploration and low Earth orbit missions. Due to the low power and thrust available on a CubeSat, low energy trajectories are necessary to allow solar system exploration. These are designed here considering a further constraint on the transfer time, which should be minimized to limit the effects of the hostile space environment on the on-board systems, typically based on components off-the-shelf. According to these issues, the topological properties of the linear dynamics in the circular restricted 3-body problem were investigated to develop a method allowing the design of internal transit and captures, including the possibility to select the osculating orbital elements at capture. Three guidance strategies are proposed, allowing modification on the ultimate behavior of trajectories to match the desired mission requirements, also in the presence of the gravitational perturbations due to a fourth body. These strategies are effective with modest velocity variations (delta-V) and are tailored to be implemented with compact continuous thrusters, compatible with CubeSats. The method was originally developed in the dynamical framework of the spatial circular restricted 3-body problem and later extended to the elliptic restricted 4-body problem. The final chapters are related to low Earth orbit missions, presenting the development of a purely magnetic attitude determination and control systems, suitable for implementation as a backup solution on CubeSats. Attitude control allows detumbling and pointing towards the magnetic field. At the same time, attitude determination is obtained from the only measurements of a three-axis magnetometer and a model of the geomagnetic field, without implementing any sophisticate filtering solution. To enhance the computational efficiency of the system, complex matrix operations are arranged into a form of the Faddeev algorithm, which can be conveniently implemented on the field programmable gate array core of a CubeSat on-board computer using systolic array architecture. The performance and the robustness of the algorithm are evaluated by means of both numerical analyses in Matlab Simulink and hardware-in-the-loop simulations in a Helmholtz cage facility.
New techniques for space science missions / Carletta, Stefano. - (2020 Jan 16).
|Titolo:||New techniques for space science missions|
|Data di discussione:||16-gen-2020|
|Appartiene alla tipologia:||07a Tesi di Dottorato|