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This deliverable aims to describe the evaluation activities of the SIMBAD project. The document contains the results of WP6, whose objective is to demonstrate and evaluate the SIMBAD performance modelling network. This involves the evaluation of the three main technical WPs of the project; namely WP3, WP4 and WP5. The document is divided in three main parts, one for each WP. In each section, the methodological approach and the evaluation results are described. References to previous deliverables of the project are present along the document, since those documents are an important source of information, both for the methodology description and for the results of each WP. The evaluation activities have been successfully accomplished. For each WP, the results obtained have been compared with the results obtained by the simulation tools or the ATM experts. The validation results confirm that the proposed machine learning techniques are able to accurately capture the behaviour of the air traffic system, while reducing the computational cost. Even considering the training costs, one can realize that the computational costs are considerably reduced, but if only the execution costs are considered, the costs are further reduced. This document is part of a project that has received funding from the SESAR Joint Undertaking under grant agreement No 894241 under European Union’s Horizon 2020 research and innovation programme.

Aircraft crew are aware of the delay they have experienced at departure. However, uncertainties ahead, and in particular holdings at arrival, can have an impact on the final performance of their operations. When optimising a trajectory the expected cost at the arrival gate should be considered. Consequently, taking into account potential congestion and extra delay at the arrival airspace is paramount to avoid taking sub-optimal decisions at the early stages of the flight. This paper presents a framework to optimise trajectories in the execution phase of the flight considering expected delays at arrival. A flight from Athens (LGAV) to London Heathrow (EGLL) is used as illustrative example, systematically exploring a range of departure delays and expected holdings at arrival.

Lambert’s problem is the orbital boundary-value problem constrained by two points and elapsed time. It is one of the most extensively studied problems in celestial mechanics and astrodynamics, and, as such, it has always attracted the interest of mathematicians and engineers. Its solution lies at the base of algorithms for, e.g., orbit determination, orbit design (mission planning), space rendezvous and interception, space debris correlation, missile and spacecraft targeting. There is abundance of literature discussing various approaches developed over the years to solve Lambert’s problem. We have collected more than 70 papers and, of course, the issue is treated in most astrodynamics and celestial mechanics textbooks. From our analysis of the documents, we have been able to identify five or six main solution methods, each associated to a number of revisions and variations, and many, so to say, secondary research lines with little or no posterior development. We have ascertained plenty of literature with proposed solutions, in many cases supplemented by performance comparisons with other methods. We have reviewed and organized the existing bibliography on Lambert’s problem and we have performed a quantitative comparison among the existing methods for its solution. The analysis is based on the following issues: choice of the free parameter, number of iterations,generality of the mathematical formulation, limits of applicability (degeneracies, domain of the parameter, special cases and peculiarities), accuracy, and suitability to automatic execution. Eventually we have tested the performance of each code. The solvers that incorporate the best qualities are Bate’s algorithm via universal variables with Newton-Raphson and Izzo’s Householder algorithm. The former is the fastest, the latter exhibits the best ratio between speed, robustness and accuracy.

The human exploration of Mars belongs to the current plans of NASA and ESA. Getting the astronauts to Mars and returning them safely to Earth imposes several engineering challenges. In particular, creating the conditions for living on the Martian surface requires in the first place a thorough understanding of the Martian environment. Installing a manned base would require the implementation of life support systems including the appropriate means to provide food to the astronauts. The word “appropriate” in this context suggests the idea of “plant cultivation”. This study is a reconstruction of the environment and climate of Mars. It develops through a review of the observation and in-situ data collected over 50 years of study and exploration. The review is followed by the study, understanding, revision and implementation of the models based on such data and on the physics of the main processes that affect the environment and the climate. The final objective is to provide a solid basis for selecting one or more candidate sites for the installation and operation of a greenhouse. Such candidates should undergo further analyses concerning the geological and engineering issues inherent to the realization of such an ambitious project. These analyses are out of the scope of this work, which focuses on the physics of the environment and the climate of the red planet. It should also be noted that the implications of this project go much beyond the specific proposed application because they have a clear scientific value and an intrinsic originality. As a matter of fact, this work has implied collecting, understanding, organizing and elaborating data and models which are often heterogeneous and dispersed. The result is the first global model of the Martian environment. As such, this study can be of considerable help in the feasibility studies of future missions to Mars, be them manned or robotic.

The return of the idea of going to the Moon throughout the last years has motivated the development of studies related with the design of lunar manned missions. This thesis covers di erent aspects related with the choice of the proper mission architecture and the manoeuvres performed during the journey, based in the approach followed by the Apollo missions. Firstly, the main alternatives presented during the development of the program and the decision criteria are explained in order to justify the election of the Lunar Orbit Rendezvous mode and discuss how this choice would have changed if it had to be taken nowadays. On the other side, an study of the main phases, using the Patched Conics Approximation to analyse the di erent orbital manoeuvres, is performed. Also, the lunar descent and ascent, and the re-entry into the atmosphere of the Earth are introduced in this study. Finally, all this results are validated using the real parameters of the mission Apollo 11

In these days it seems that, in another context, a new space race has began withthe objective of reaching Mars with humans on board for the first time. Exempli-fied by various agencies and private companies’ efforts, such as NASA orSpaceX,at this same moment their projects are mainly focused on developing the necessarymeans to reach the red planet as soon as possible. For this reason, this study aimsto develop the necessary tools to analyse every phase of an Earth to Mars missionfocusing on NASA’s proposed mission architecture. So, would it be feasible to bringhumans to Mars using the suggested timelines and technologies?To try to answer to this question, this thesis attempts to develop a series of soft-ware gadgets using numerical methods, with the purpose of obtaining a set of dataregarding the existent launch opportunities to travel from Earth to Mars througha specified date range. The study also includes the design of a series of graphicalinterfaces to support the analysis of the manoeuvres to be performed in a missionof this characteristics. Thus, with the initial obtained information and with theassistance of the developed tools, two mission timelines including the analysis ofevery manoeuvre to be performed have been defined and presented in this report;one of them according to NASA’sDesign Reference Architecture, while the otherone suggests an architecture aimed to create a one million population city on Mars’soil.The results obtained indicate that a powerful analysis tool for inspecting the pre-liminary phases of a space mission design has been developed in this thesis, fulfillingthe mandatory requirements and being useful to study any space mission to Marsin the future

Although they normally go together, the world of environmental monitoring and water monitoring often go their separate ways. There are sensor arrays that do one of two things, but the options are greatly reduced if we talk about the latter. In addition,they are usually very expensive and complex devices to use. This document seeks to create a project that includes water monitoring and environmental monitoring with the premises that it is inexpensive, simple to use and that it is widely used in order to gaina foothold in the market for several applications like in farms, water treatment plants or fish factories, for example.The proposed system consists of simulating a matrix of 9 sensors that monitor waterand the environment in real time and send the data to a smartphone application createdfor the purpose of the project to be able to control the systems remotely. The projecthas a notification system that notifies the user if there is a problem so that a solution can be applied quickly. The smartphone app is by far the most accomplished goalof the project and could be used as a graphical interface for any other monitoring project.Furthermore, being a simulation, the project identifies alternatives to the different sensors and focuses on a main stage, a treatment plant in Burkina Faso. From there, all the values and sensors can be changed by others that are named in the job depending on the situation in which you want to apply the project.The project also tries to offer the highest quality in the data received without jeopardizing the safety of the devices or operators and also looking for a balance between cost and quality of the product.

Space is going through a new evolution, where the objectives are much more ambitious than before thanks to the new technologies. The possibilities that arise from these new achievable projects are grateful, such as creating human stations in satellites, oreven building cities for human being in other planets. In order to achieve these goals, the biggest problematic currently is the transport method, that is to say, how to reach distant celestial bodies in a viable way, focusing on both the feasibility for the human life and the economic aspects, and the first proposal is to reach Mars.To do so, a patched conic approximation will be performed so as to analyse the Earth to Mars interplanetary transfer. By using a Newton-Raphson iterative process, which includes a continuation method with a differential corrector, the Lambert problem will be solved in order to obtain the main results. It will also be done a main-materials estimation for the Mars society competition, defined as a case study of the project.On the other hand, the privatization of the space sector is adding new players to the game, and as a result of this, a new space race is taking place. The most outstanding players nowadays are NASA, on the side of government agencies, and SpaceX, from the private space sector. Both companies have presented strategies to reach the red planet, and this study is focused on the architecture analysis of the SpaceX mission, in order to analyse each of its phases, to compute the trajectory and to develop a preliminary study of the re-entry manoeuvre. Furthermore, due to the current situation, in which the interest of the manned interplanetary journeysis booming, it is important to define the suitability of the whole mission. Because of the high investment required for conducting a Mars’ colonization process, a preliminary materials budget and a first iteration of the total cost of the program will be conducted, trying to roughly quantify the amount necessary to develop the project globally.

The gravitational assist manoeuvre is a key component of modern interplanetary trajectory design. It allows to save a great amount of fuel, which makes it an extremely appealing option as a design choice. The goals of this study are: Investigate the mechanics of the natural gravity assist. Develop a strategy using natural gravity assist manoeuvres in the workframe of an interplanetary trajectory mission. In recent years space exploration has become more and more prolific. Its nature has changed, from a public state-funded (rather unusual) activity with a main goal of challenging human and physical barriers to a private industry that has seen the opportunity to take advantage of resources outside Earth. An industry that could provide the solution for the unsustainable demand in energy and basic resources generated by an exponentially increasing population. Certainly, space exploration is nowadays far away from overtaking long ago established industries such as fossil fuels. Why chasing an asteroid when you could dig oil out on Earth and at lower costs? The answer is simple: one day no resources will be left. Several companies dedicated to space exploration and exploitation do have scheduled projects for the years to come, and mission design is key for success. Natural Gravity Assist is just one of the many different approaches a space mission can implement, depending on the size of the payload (so, consequently the spacecraft), the trajectory and celestial bodies that affect it, or even its primary goal: a satellite probe for a first scientific scanning or a two-way mission involving launches and landings? Nevertheless, implementing the Natural Gravity Assist manoeuvre is a paramount contribution: using the gravitational field of other planets allows to shape the trajectory and even more remarkable, it saves fuel. One can find a huge amount of research papers and literature dealing with the Natural Gravity Assist problem and formulation, however, those solutions are predominantly in the form of scalar equations, crowded with angles and impossible to intuitively imagine the geometry. In this paper a new analytic model is proposed relying on vector algebra making it more robust, concise and elegant. This method is tested with benchmark runs reproducing the well-known Voyager 1 mission and later on obtaining by optimization (again) Voyager 1, Voyager 2 and Mariner 10. Eventually, two asteroid-rendezvous missions (to Ryugu and Nereus, both asteroids being a current target for mining companies) are simulated. Benchmark runs successfully achieve to reproduce the real missions while asteroid rendezvous missions improve considerably fuel consumption in contrast to direct transfers. However, the results per se do not constitute the most substantial part of this research, but the restrictions, considerations and limitations around them. All of these three set a starting point for other research branches and a deeper understanding of celestial mechanics problems, simultaneous optimization for many variables, search space pruning, etc.

The Tisserand graph allows to find feasible interplanetary transfers in the frame of the multi-gravity assist trajectory design. An optimisation technique relying on this tool would allow for an automatic planetary sequence selection, which would then be used in a more general inteplanetary optimisation method. This study aims at the:- Implementation of an automatic path-finding method using the Tisserand graph.- Assembly of the previous method into an established multi-gravity assist optimiser. Nowadays, technology advances have given us the chance to achieve things that a couple generations ago could not even dream of. Space exploration is one of those achievements and space mission designing is a vital part of it. Since the firsts space missions, the methods used to design them have been increasingly evolving and sophisticating with time. Scheduling a space mission is a complex task that takes time and effort to achieve. A crucial factor to determine a space mission trajectory is cost, which is basically reflected in the fuel used to accomplish the mission. In order to reduce the quantity of propellant used in a mission, multi-gravity assists provide the capability to the spacecraft of altering its speed and path. Throughout this process, analysis to optimize the path of the mission are done. To do so, the optimizers need a list of planet sequences to start analyzing. A first approach to obtain viable lists of planets is using Tisserand graphs. The Tisserand graph is a graphical tool developed to aid in searching for paths for a space mission. The aim of this bachelor’s thesis is to implement a code that uses a tree search algorithm to find viable multi-gravity-assist trajectories from a Tisserand graph in an automatic manner. Several versions of the code have been implemented until reaching a definitive version that fulfills the requirements of the thesis. The final version uses a depth-limited search algorithm to explore a search tree generated automatically in an iterative process from a Tisserand graph, storing in the process all the found flybys sequences.

The optimisation of interplanetary trajectories is a challenging field. Nowadays many optimisation techniques rely on the islands model, but few analysis about the performance of such technique have been carried out. The goals of this study are:- Analysis of the performance of the islands model optimisation algorithm applied to several interplanetary trajectories scenarios.- Parametric optimisation of the islands model configuration parameters. The study of interplanetary trajectories is a field with many difficulties due to the complexity of the problem at hand. Finding a trajectory that fulfils all the position, time and fuel consumption requirements is a complicated task. In order to find good trajectories, this study uses a multi-gravity assist based approach, coupled with an island model optimiser that executes in parallel some variants of genetic algorithm, differential evolution and particle swarm optimisers. On this thesis, the algorithm will be applied to three different scenarios: a fictional Earth-Mars direct launch and the Mariner 10 and Voyager 2 missions. These have been selected to represent a broad range of scenarios: a direct launch between two planets, a mission towards the inner planets of the Solar System and a mission directed towards the outer ones. The first goal of the study is to determine whether using an island model improves the performance of the genetic algorithm, differential evolution and particle swarm algorithms executed stand-alone (without the island model). Then, we analyse whether mixing algorithms (heterogeneous island model) provides any benefits to the simple island model. Ultimately, a parametric performance analysis is carried out to determine the behaviour of the island model parameters. The results show that using an island model in an algorithm improves its performance in most cases. Both methods find the same optimal regions, but the island model offers more accurate results. Additionally, mixing algorithms in the island model helps achieving a higher stability, but, at the same time, it lowers the probability of finding the best solution. The island model, in a general fashion, shows an improvement when the number of islands is equal or inferior to 10. It also usually needs a minimum of 20 global generations to find the best solution, while the heterogeneous island model shows better results with less than five global generations. The use of the migration operator improves the general performance of the optimiser. Regarding the number of emigrants, the results are inconclusive. Ultimately, for a variable number of synodic periods, the island model does not show any significant improvement over the basic algorithms due to the use of too many individuals and iterations.

The Tisserand graph is a graphical method used for interplanetary trajectory design. Nowadays the graph is used by expert hand to manually select feasible solutions, so the automatisation of the selection process is desired. This study aims to:- Identify potential automatisation procedures to find solutions on the Tisserand graph.- Analyse the suitability of the proposed procedures and selection of the optimal one. Interplanetary missions have awoken the interest of space agencies with the objective of discovering and analyzing distant planets. Distant targets become impractical to explore due to the large amount of propellant that is needed, and therefore saving fuel becomes of great use in such missions. The use of gravity-assist saves fuel by using the gravitational field of planets in order to modify the heliocentric velocity of a spacecraft or probe. The Tisserand graph is a useful tool that can be used to find sequences of gravity-assists in order to reach a target planet, and for that reason it becomes a powerful tool in preliminary mission design. In this thesis, a method to find paths in a complete automatic manner on the Tisserand graph is described and developed. The outcome of this study is an algorithm that can find all possible sequences of planets in order to reach a goal planet. The algorithm aims to be as general as possible, so it can be applied to multiple orbital systems.

Sending spacecrafts to any other planet or satellite within the Solar System is a difficult task. To be able to reach it at a precise time, it is crucial to know at which position the target planet is going to be, as well as a good study of the trajectory that the spacecraft is going to follow, which shall not be too close to any other object in the Solar System. It must be also be taken into account that the spacecrafts have a limited fuel capacity. In order to avoid using a high amount of fuel, multi-gravity assist trajectories are useful to provide additional manoeuvering to the spacecrafts without consuming fuel. Given an arbitrary sequence of planets for the swing-by manoeuvres, the next step is to determine when the spacecraft must be launched and how long will it take to it to perform the transfer trajectory. In this preliminary stage of the mission analy-sis, optimization algorithms can be used to obtain the most efficient trajectory, for instance, the trajectory at which the spacecraft requires the least amount of fuel to reach its destination. From the wide variety of heuristic optimization algorithms, in this Master’s thesis four of them have been chosen (Genetic Algorithm, Differential Evolution Algorithm, Particle Swarm Algorithm and the simulated annealing algorithm). The aim of this thesis is to perform a hyperparameter optimization, that is, finding whether a certain combination of parameters for each optimizer works properly for different trajecto-ries’ scenarios: a direct launch to an outer planet and a multi-gravity assist scenario to outer planets as well as to inner planets. The results show that it exists a region of parameters for the Genetic Algorithm and the Differential Evolution Algorithm where the best solutions can be found. Simulated Annealing Algorithm shows a dependance on the scenario, as well as some parameters of the Particle Swarm Algorithm.

The objective of this work is the computational analysis of the in-flight deformation of a commercial paraglider wing and its impact on the aerodynamic performance. Particular emphasis will be given to the so-called ovalization of the wing cells, which changes the airfoil shape between ribs and the aerodynamic response of the sections. The study will be carried out using the software PARACHUTES, which is a low-order coupled simulation software designed for fast practical analysis. The goal of this work is to compute the performance of a paragliding wing taking into account thein-flight shape deformation. To this end, a fluid-structure solution approach combining inviscidaerodynamics with viscous corrections is adopted. The computer program Parachutes (basedon a Panel Method) is used to find the potential lift distribution. Then, this value is correctedusing the 2D viscous polars of each airfoil section across the span. Since the wing pressure can deform the geometry the airfoil sections change along the span. Thus, an extrapolationtechnique is developed to predict the polar curves of the deformed sections taking as a reference the undeformed (original) shape. To do so, a parametric study is carried out in order to find the most common deformation mechanisms and the effects they have on the airfoil aerodynamics.