Artículos (Ingeniería Aeroespacial y Mecánica de Fluidos)

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  • EmbargoArtículo
    Performance of a felt based living wall with greywater irrigation using different indoor ornamental species
    (Elsevier, 2025-02) Fernández Cabanás, Víctor Manuel; Suárez Cáceres, Gina Patricia; Fernández Cañero, Rafael; Rossini Oliva, Sabina; Pérez Urrestarazu, Luis; Universidad de Sevilla. Departamento de Agronomía; Universidad de Sevilla. Departamento de Biología Vegetal y Ecología; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos
    Vertical greening systems are becoming popular nature-based solutions for including vegetation in the built environment. However, one of the main concerns regards to their water requirements. The use of greywater for their irrigation can be a solution. While several studies have proven that using living walls as a biofilter can improve the quality of the greywater applied for their irrigation, the effects on the vegetation of continuous irrigation with greywater are still unknown. The main objective of this work is the assessment of the vegetation performance using different plant species in indoor living walls exclusively irrigated with greywater. For that, three species (Philodendron hederaceum, Spathiphyllum wallisii and Nephrolepis exaltata) planted on felt-based living wall modules were tested for 30 weeks. Information regarding the main water quality parameters (pH, electrical conductivity (EC), concentration of major cation and anions, chemical oxygen demand (COD) and biological oxygen demand for an incubation period of 5 days (BOD5) were obtained and the development of the vegetation was monitored. The three species adapted well to the continuous irrigation with greywater, though S. wallisii showed a slight decrease in green cover at the end of the study. As the greywater was recirculated, EC increased with time, but no clear effects on growth and appearance were observed in the plants. This suggests the need of periodically replacing the greywater used for irrigation or including irrigation events with freshwater.
  • Acceso AbiertoArtículo
    What does it take to renature cities? An expert-based analysis of barriers and strategies for the implementation of nature-based solutions
    (Elsevier, 2024-03) Castellar, Joana A.C.; Popartan, Lucia Alexandra; Pucher, Bernhard; Pineda-Martos, Rocío; Hecht, Katharina; Katsou, Evina; Nika, Chrysanthi Elisabeth; Junge, Ranka; Langergraber, Günter; Atanasova, Nataša; Comas, Joaquim; Monclús, Hèctor; Pueyo-Ros, Josep; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; European Union (UE); Ministerio de Ciencia e Innovación (MICIN). España
    This paper uses an expert-based methodology to survey the barriers and strategies related to the implementation of nature-based solutions (NBS). The ambition of the paper is to offer a bird's eye overview of the difficulties encountered by NBS deployment and ways to overcome them. With a wide participation of 80 experts from COST Action Circular City, we identify barriers specific to 35 pre-defined NBS of the following four categories: Vertical Greening Systems and Green Roofs; Food and Biomass Production; Rainwater Management; and Remediation, Treatment, and Recovery. The research sheds light on how a major interdisciplinary – yet predominantly technically-oriented - community of scientists and practitioners views this important topic. Overall, the most relevant barriers are related to technological complexity, lack of skilled staff and training programs and the lack of awareness that NBS is an option. Our results highlight concerns related to post implementation issues, especially operation and maintenance, which subsequently affect social acceptance. The paper identifies a “chain” effect across barriers, meaning that one barrier can affect the existence or the relevance of other barriers. In terms of strategies, most of them target governance, information, and education aspects, despite the predominantly technical expertise of the participants. The study innovates with respect to state-of-the-art research by showing a fine-grained connection between barriers, strategies and individual NBS and categories, a level of detail which is not encountered in any other study to date.
  • Acceso AbiertoArtículo
    Urban agriculture as a keystone contribution towards securing sustainable and healthy development for cities in the future
    (IWA Publishing, 2020-01-01) Skar, Siv Lene Gangenes; Pineda-Martos, Rocío; Timpe, Axel; Pölling, Bernd; Bohn, Katrin; Külvik, Mart; Delgado, Cecília; Pedras, Celestina M.G.; Paço, Teresa A.; Ćujić, Mirjana; Tzortzakis, Nikos G.; Chrysargyris, Antonios; Peticilǎ, G. A.; Alencikiene, Gitana; Monsees, Hendrik; Junge, Ranka; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; European Union (UE)
    Research and practice during the last 20 years has shown that urban agriculture can contribute to minimising the effects of climate change by, at the same time, improving quality of life in urban areas. In order to do so most effectively, land use and spatial planning are crucial so as to obtain and maintain a supportive green infrastructure and to secure citizens' healthy living conditions. As people today trend more towards living in green and sustainable city centres that can offer fresh and locally produced food, cities become again places for growing food. The scope of urban agriculture thereby is to establish food production sites within the city's sphere; for example, through building-integrated agriculture including concepts such as aquaponics, indoor agriculture, vertical farming, rooftop production, edible walls, as well as through urban farms, edible landscapes, school gardens and community gardens. Embedded in changing urban food systems, the contribution of urban agriculture to creating sustainable and climate-friendly cities is pivotal as it has the capacity to integrate other resource streams such as water, waste and energy. This article describes some of the current aspects of the circular city debate where urban agriculture is pushing forward the development of material and resource cycling in cities.
  • Acceso AbiertoArtículo
    Perceptions of stakeholders on nature-based solutions in urban planning: A thematic analysis in six European cities
    (Elsevier, 2024-06) Megyesi, Boldizsár; Gholipour, Amir; Cuomo, Federico; Canga, Eriona; Tsatsou, Alexandra; Zihlmann, Violeta; Pineda-Martos, Rocío; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos
    A commonly addressed aspect of urban planning involves the integration of nature-based solutions (NBS). Before applying NBS, acquiring stakeholders' viewpoints, e.g., city councils, local governments, and academia, contributes to the successful application and thus to mitigation of global challenges such as climate change, loss of biodiversity, water, and food scarcity. The present study explores how stakeholders across Europe view the role of NBS in urban planning. A thematic analysis was conducted to identify patterns, themes, and concepts within interview transcripts gathered through semi-structured interviews held in Budapest, Cordoba, Ljubljana, Reykjavik, Vienna, and Zurich. The study resulted in 107 distinctive codes categorized into NBS benefits, challenges, opportunities, NBS actors, and regulations. The frequency of codes (Fr) mentioned by the interviewees showed that NBS benefit cooperation (Fr=125) between individuals, while the most challenging issue obstructing NBS implementation was the lack of NBS knowledge (Fr=93). The need for green areas (Fr=42) was identified as an opportunity that could give rise to NBS applications. This study also provides practical recommendations to overcome some barriers when implementing NBS.
  • Acceso AbiertoArtículo
    Moving Towards a Holistic Approach to Circular Cities: Obstacles and Perspectives for Implementation of Nature-Based Solutions in Europe
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024-08) Ristic Trajkovic, Jelena; Krstic, Verica; Milovanović, Aleksandra; Calheiros, Cristina S. C.; Cujic, M.; Karanac, Milica; Pineda-Martos, Rocío; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; European Union (UE). H2020
    Nature-based solutions (NBS) are frequently implemented without taking the system’s perspective into account and with the main focus on technical and economic issues of implementation. This study was conducted to test the hypothesis on the potential synergistic effects between circularity and NBS to holistically tackle urban challenges. The main objective is to establish preliminary insights on the obstacles and perspectives of NBS integration and implementation, through a questionnaire set up by the network of experts gathered within the COST Action CA17133 Circular City. The following research questions arise: (i) what differences exist in the level of NBS application according to the variance of engaged countries; and (ii) what are the main obstacles and perspectives for the NBS implementation in order to holistically tackle urban challenges, enhancing the sustainable connection among urban environment, nature, and human well-being. To go beyond the current state-of-the-art and reflect on the research conducted within the Circular City Action, this study aims to open a multi-geographical academic dialogue across Europe and beyond and to move towards a holistic approach to circular cities. Accordingly, this study is: (1) multi-geographical and context-based, providing input for thirty-three EU countries and four non-EU countries to give an overview of the main obstacles and perspectives of NBS implementation, and (2) approach-directed, aiming to formulate a holistic approach to deal with societal challenges. This document intends to provide qualitative and quantitative insight into the potentials and obstacles of NBS implementation in Europe, as well as to motivate further discussion and research to achieve holistic and sustainable cities.
  • Acceso AbiertoArtículo
    Cultivating Sustainable Construction: Stakeholder Insights Driving Circular Economy Innovation for Inclusive Resource Equity
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024-04) Karaca, Ferhat; Tleuken, Aidana; Pineda-Martos, Rocío; Ros Cardoso, Sara; Orel, Daniil; Askar, Rand; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Diputación Provincial de Córdoba
    Due to its intricate production processes, complex supply chains, and industry-specific characteristics, the construction industry faces unique challenges in adopting circular economy (CE) principles that promote resource equity. To address this issue, this study aims to delve into identifying stakeholders’ opinions and perceptions regarding key CE strategies across different stages of the building life cycle (BLC). Both European and non-European stakeholders within the “CircularB” COST Action network and beyond participated in this research. Three methods were employed to assess stakeholders’ opinions: an online survey, a structured survey with a semi-guided workshop, and creative thinking round table discussions. Natural language processing (NLP), specifically topic modelling and sentiment analysis, was used to analyse the data collected from the online survey, which gathered text-based opinions from 209 participants on the cost-benefit aspects of circularity strategies. The structured survey, which collected data from 43 workshop participants, evaluated the perceived importance of CE strategies across various BLC phases and assessed the adoption of selected CE strategies in current or past projects. Finally, the Six Thinking Hats® activity, employed in the round table discussions, generated ideas from 25 professionals regarding the broader implementation challenges and opportunities of CE in construction. The research findings highlight the need to bridge the gap between theory and practice by fostering active industry stakeholder involvement in the transition to a CE model. The analyses of the collected stakeholder opinions through the three activities contribute to proactive and collaborative efforts aimed at advancing resource equity in the construction sector and promoting just and inclusive resource use. In summary, this research offers a comprehensive understanding of stakeholders’ opinions on CE strategies and provides guidance for the development of targeted policies and strategies to accelerate the integration of CE principles in the construction industry.
  • Acceso AbiertoArtículo
    Nature-Based Solutions in Cities—Contribution of the Portuguese National Association of Green Roofs to Urban Circularity
    (Springer Nature, 2021-11) Pineda-Martos, Rocío; Calheiros, Cristina S.C.; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Universidad de Sevilla; European Union (UE). H2020
    Green building–integrated systems and technologies (e.g., green roofs (GR) and walls (GW)) are classified as nature-based solutions (NBS) in the context of urban green infrastructure (GI), which contribute to add both natural elements and processes, as a result of locally designed, resource-efficient, and systemic interventions in cities. They have also been considered to address several urban challenges towards cities’ circularity. The European Union (EU) Biodiversity Strategy and the Action Plan recently adopted by the European Commission, represent a comprehensive long-term programme aspiring to protect nature and reversing the ecosystem degradation by 2030. Sustainable and resilient societies under the challenge ‘innovating with nature’ are the leading aim of the EU Research and Innovation (R&I) policy agenda goals on NBS and re-naturing urban areas. The European GI/NBS Associations build the bridge to provide a network among stakeholders from academia, municipalities, entrepreneurs and private-sector entities and other non-governmental organisations, by creating a platform to build and share knowledge and create collaboration on sustainable GI/NBS, regarding building-integrated vegetation approaches as well as related policies, regulations and technical guidelines. The commitments of the foundations to encourage and promote the advanced adoption of green urban infrastructure practice and planning as part of the built environment, drive active efforts to support NBS innovation objectives and the transition from ‘grey to green’ infrastructure. The present manuscript aims at reflecting the crucial role of the Associations on GI/NBS, mainly GR and GW, to develop local frameworks applying innovative plans of action, and allocate R&I opportunities implementing relevant and inclusive urban regeneration solutions. Within this context, it will be highlighted the example of the Portuguese National Association of Green Roofs.
  • Acceso AbiertoArtículo
    A new robust adaptive mixing control for trajectory tracking with improved forward flight of a tilt-rotor UAV
    (Elsevier, 2021-04) Cardoso, Daniel N.; Esteban Roncero, Sergio; Raffo, Guilherme V.; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Instituto Nacional de Ciência e Tecnologia para Sistemas Autônomos Cooperativos (InSAC). Brasil); Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior. Brasil; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Brasil; Fundação de Amparo à Pesquisa do Estado de Minas Gerais. Brasil; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
    A new robust adaptive mixing control (RAMC) is proposed in order to accomplish trajectory tracking of a tilt-rotor unmanned aerial vehicle (UAV) configuration. This kind of system is a hybrid aerial vehicle that combines advantages of rotary-wing aircraft, like hovering flight and vertical take-off and landing (VTOL), and those of fixed-wing aircraft, as improved forward flight. Although the VTOL and cruise flight regimes present different dynamic behaviors, in this work a unified, highly coupled, nonlinear model is developed to cope with the considered tilt-rotor UAV full flight envelope, that is, the axial flight, hovering, transition/cruise and turning flight. The modeling is performed via Euler–Lagrange formulation considering the tilt-rotor UAV as a multi-body system and taking into account aerodynamic effects and the dynamics of the tilting servomotors. Accordingly, in order to comply with the trajectory tracking requirements and improve the tilt-rotor UAV forward flight, this paper presents a novel robust adaptive mixing controller which is formulated to deal with linear parameter-varying (LPV) systems dependent on not known a priori large parameters but measured or estimated online, and also to provide robustness against unknown disturbances. Additionally, a rigorous closed-loop stability analysis is performed. The controller performance is validated with numerical experiments conducted using a high fidelity simulator developed on Gazebo and Robot Operating System (ROS) platforms.
  • Acceso AbiertoArtículo
    A robust optimal control approach in the weighted Sobolev space for underactuated mechanical systems
    (Elsevier, 2021-03) Cardoso, Daniel N.; Esteban Roncero, Sergio; Raffo, Guilherme V.; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos
    This paper proposes new robust nonlinear optimal control formulations in the weighted Sobolev space, here called nonlinear and controllers, to handle with two classes of underactuated mechanical systems: the reduced ones with a reduced number of DOF; and the entire underactuated mechanical systems with input coupling. The optimal control problems are formulated via dynamic programming and particular solutions are presented for the resulting Hamilton–Jacobi equations with the corresponding stability analysis. Also, the concepts of -stability and -gain for a general class of systems are established, with the demonstration for the particular case of study. The novel and controllers are synthesized for an unmanned aerial vehicle benchmark. The results demonstrate that these controllers provide better transient performance with faster response against external disturbances in comparison with a classic nonlinear controller, in addition to have a simple design.
  • EmbargoArtículo
    Enhanced robust adaptive flight control for a convertible VTOL UAV
    (Elsevier, 2024-03) Campos, Jonatan M.; Cardoso, Daniel N.; Esteban Roncero, Sergio; Raffo, Guilherme V.; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Institutos Nacionais de Ciência, Tecnologia e Inovação. Brasil; Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior. Brasil; Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG). Brasil; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
    In this paper, we propose less conservative formulations for candidate controllers of robust adaptive mixing control (RAMC) strategies. The RAMCs are employed to solve the trajectory tracking problem throughout the full flight envelope, with guaranteed stability, of a convertible plane (CP) vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV). Initially, the multi-body nonlinear dynamic model of the CP VTOL UAV is obtained using the Euler–Lagrange formalism, from which a linear parameter-varying (LPV) model is derived to be used in the design of the RAMC candidate controllers. The new formulations of the candidate controllers are proposed considering two approaches: a (i) Parallel Distributed Compensation (PDC); and (ii) a parameter-dependent Lyapunov function. Hardware-In-the-Loop (HIL) experiments are performed in a high-fidelity flight simulator to verify the fulfillment of real-time constraints, ensuring a computationally lightweight control strategy ready for implementation in a low-cost embedded computational system.
  • Acceso AbiertoArtículo
    Wind Tunnel Aerodynamic Study of a VTOL-UAV for Wide Range of Angles of Attack and Sideslip Angles
    (Springer Nature, 2021-03) Prieto Rueda, Victoria; Esteban Roncero, Sergio; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
    This article presents the design, manufacturing and wind tunnel tests conducted on a 1:4 scaled Vertical Take Off and Landing (VTOL) Unmanned Aerial Vehicle (UAV). A brief description of the VTOL model, identifying characteristic dimensions, along with the manufacturing process for the scale model and the measurement equipment is presented. Results of the wind tunnel experiments are conducted varying both angle of attack and sideslip angle for a wide rage of the angles, and several wind tunnel speeds, thus allowing to characterize the full flight envelope for all three flight phases of the VTOL-UAV: axial, transition and cruise flight phases. A description of the wind tunnel measuring setup and the methodology used is presented, along with the subsequent analysis and corrections considered for all the data obtained, presenting a discussion about the results and its comparison with numerical analysis obtained with CFD studies. Finally, some conclusions and recommendations are made with the main objective of establishing a basis for future tests.
  • Acceso AbiertoArtículo
    Robust Model Predictive Control for an Ion Beam Shepherd in a large-debris removal mission
    (Elsevier, 2024-12) Urrios Gómez, Francisco Javier; Vázquez Valenzuela, Rafael; Gavilán Jiménez, Francisco; Alvarado Aldea, Ignacio; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Universidad de Sevilla. Departamento de Ingeniería de Sistemas y Automática; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; European Union (UE)
    The increasing accumulation of space debris poses significant risks to spacecraft, making the development of effective debris mitigation technologies necessary. This paper explores the Ion Beam Shepherd (IBS) method as a potential contactless solution for deorbiting large debris objects. The IBS system concept involves a spacecraft equipped with an ion thruster to direct a controlled ion beam at the debris, generating a small force that gradually lowers its orbit. A proposed configuration of the chaser’s actuator system integrates radial and out-of-plane cold-gas thrusters along with in-track ion thrusters to enhance control and safety while maintaining low mission costs. A robust Model Predictive Control (MPC) strategy is implemented, using the theory of MPC for Tracking to ensure accurate positioning and effective deorbiting. This theoretical approach addresses uncertainties and perturbations to robustly guarantee safe distances between the chaser and the debris. Additionally, a new ray-marching-based algorithm is introduced to estimate the force and torque exerted by the ion beam on the target, considered as a 6 degrees of freedom object, improving simulation accuracy and control performance assessment. A comprehensive simulation of the deorbit of a large debris object is performed, demonstrating the potential of the IBS technology for future large-debris removal missions. This research advances the conceptual framework and control techniques for the IBS technology, advancing towards its future implementation in space debris mitigation.
  • Acceso AbiertoArtículo
    A Symmetry-Based Unscented Particle Filter for Rapid State Estimation for SAL Guided Vehicles
    (IEEE, 2024) Rebollo Fernández, José Antonio; Gavilán Jiménez, Francisco; Vázquez Valenzuela, Rafael; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos
    The state estimation problem for vehicles with highly uncertain initial conditions and limited, varying sensors is crucial for both aircraft and spacecraft navigation. This work introduces a Locally Linearized Particle Filter based on a quaternion-adapted Unscented Kalman Filter to estimate the state of a free-fall laser-guided bomb with minimal sensors and uncertain initial conditions. The available sensors include accelerometers, gyroscopes, a barometric altimeter, and a semi-active laser (SAL) receiver that activates only when the target is close and within line-of-sight. Assuming no communication between the carrier aircraft and the bomb (so that the aircraft cannot feed the bomb its launch position and velocity), the algorithm exploits the problem's symmetry to rapidly reconstruct the relative position, velocity, and attitude of the target, even with uncertain initial conditions and insufficient sensor data. In addition, the filter initiates an identification algorithm to estimate the ballistic coefficient, which predicts the miss distance. The proposed algorithm shows promising results in Monte Carlo simulations, quickly converging to an accurate trajectory estimate and providing a high quality aerodynamic model and future trajectory predictions.
  • Acceso AbiertoArtículo
    The determination of total phosphorus improves the accuracy of the bicarbonate extraction as an availability index
    (Wiley, 2019-02-03) Recena Garrido, Ramiro; Díaz de la Torre, Isabel; García López, Ana M.; Delgado García, Antonio; Universidad de Sevilla. Departamento de Agronomía; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos
    The efficient use of phosphorus (P) in agriculture should rely on accurate soil P tests (SPT). Organic P contributes to P supply to plants; however, it is not usually taken into account in assessing P fertilizer requirements. We hypothesized that there would be an increased accuracy of bicarbonate extraction as SPT in predicting P uptake by plants if total P (TP) in this soil extract is taken into account. We conducted a soil P depletion experiment with 36 soils involving four consecutive crops in pots. Molybdate-reactive P (MRP) and total P were determined in extracts centrifuged at 19,000 g (Bic-MRPC and Bic-TPC) or not (Bic-MRP and Bic-TP). MRP in extracts explained <47% of the variance in the cumulative P uptake, while total P (centrifuged at 19,000 g or not) provided the most accurate estimation of P uptake (59% with Bic-TP) and threshold values for fertilizer response (R2 = 0.58 with Bic-TPc). When soils were separated in two groups according to their Ca carbonate equivalent to clay ratio, the variance in the cumulative P uptake explained by Bic-MRP was above 63%, and that explained by Bic-TP was above 73%. This separation also enabled more realistic estimation of the threshold values for fertilizer response. It can be concluded that the use of total P instead of MRP in bicarbonate extraction was promising in terms of improving its accuracy in assessing P fertilizer requirements.
  • EmbargoArtículo
    Manoeuvre detection in Low Earth Orbit with radar data
    (Elsevier, 2023-10) Montilla García, José Manuel; Sánchez Merino, Julio César; Vázquez Valenzuela, Rafael; Galán Vioque, Jorge Francisco; Rey Benayas, Javier; Siminski, Jan A.; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Universidad de Sevilla. Departamento de Matemática Aplicada II (ETSI); Universidad de Sevilla
    This work outlines and assesses several methods for the detection of manoeuvres in Low Earth Orbit (LEO) from surveillance radar data. To be able to detect manoeuvres, the main starting assumption is that the object under analysis has an orbit known with a sufficient degree of precision. Based on the precise (a posteriori) orbit and radar data, several manoeuvre detection methods are presented; one is based on unscented Kalman filtering, whereas two others algorithms are based on reachability analysis of the state, which correlates its prediction set with the next track from the radar. The filtering algorithm can be extended for several radar tracks, whereas the reachability-based methods are more precise in detecting manoeuvres. Then, to inherit the best properties of both classes of algorithms, a manoeuvre detection filter that combines both concepts is finally presented. Manoeuvre detection results are analysed first for simulated scenarios—for validation and calibration purposes—and later for real data. Radar information comes from the Spanish Space Surveillance Radar (S3TSR), with real manoeuvre information and high-quality ephemerides. The results show promise, taking into account that a single surveillance radar is the only source of data, obtaining manoeuvre detection rates of more than 50% and false positive rates of less than 10%.
  • Acceso AbiertoArtículo
    Chance-constrained Model Predictive Control for Near Rectilinear Halo Orbit spacecraft rendezvous
    (Elsevier, 2020-05) Sánchez Merino, Julio César; Gavilán Jiménez, Francisco; Vázquez Valenzuela, Rafael; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Universidad de Sevilla; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
    This work presents a robust Model Predictive Controller (MPC) to solve the problem of spacecraft rendezvous in the context of the restricted three-body problem (R3BP) as will be required to dock with space stations in cislunar space. The employed methodology is both valid for chemical and electric thrusters. By exploiting the state transition matrix and using a chance-constrained approach, the robust MPC assures constraints satisfaction under the presence of disturbances in a probabilistic sense. The perturbations parameters are computed on-line using a disturbance estimator. The robust controller is tested for a rendezvous scenario with a target placed in an Earth-Moon Near-Rectilinear Halo Orbit. Numerical results are shown and discussed.
  • Acceso AbiertoArtículo
    Orbit-Attitude Predictive Control in the Vicinity of Asteroids with In Situ Gravity Estimation
    (American Institute of Aeronautics and Astronautics, 2022-02) Sánchez Merino, Julio César; Vázquez Valenzuela, Rafael; Biggs, James D.; Bernelli-Zazzera, Franco; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Universidad de Sevilla; Ministerio de Ciencia e Innovación (MICIN). España
    This paper presents an integrated model-learning predictive control scheme for spacecraft orbit-attitude station-keeping in the vicinity of asteroids. The orbiting probe relies on optical and laser navigation while attitude measurements are provided by star trackers and gyroscopes. The asteroid gravity field inhomogeneities are assumed to be unknown a priori. The state and gravity model parameters are estimated simultaneously using an unscented Kalman filter. The proposed gravity model identification enables the application of a learning-based predictive control methodology. The predictive control allows for a high degree of accuracy because the predicted model is progressively identified in situ. Consequently, the tracking errors decrease over time as the model accuracy increases. Finally, a constellation mission concept is analyzed in order to speed up the model identification process. Numerical results are shown and discussed.
  • Acceso AbiertoArtículo
    Assessing SOC Estimations via Reverse-Time Kalman for Small Unmanned Aircraft
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024-08) Arahal, Manuel R.; Pérez Vega-Leal, Alfredo; Garrido Satué, Manuel; Esteban Roncero, Sergio; Universidad de Sevilla. Departamento de Ingeniería de Sistemas y Automática; Universidad de Sevilla. Departamento de Ingeniería Electrónica; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Agencia Estatal de Investigación. España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
    This paper presents a method to validate state of charge (SOC) estimations in batteries for their use in remotely manned aerial vehicles (UAVs). The SOC estimation must provide the mission control with a measure of the available range of the aircraft, which is critical for extended missions such as search and rescue operations. However, the uncertainty about the initial state and depth of discharge during the mission makes the estimation challenging. In order to assess the estimation provided to mission control, an a posteriori re-estimation is performed. This allows for the assessment of estimation methods. A reverse-time Kalman estimator is proposed for this task. Accurate SOC estimations are crucial for optimizing the utilization of multiple UAVs in a collaborative manner, ensuring the efficient use of energy resources and maximizing mission success rates. Experimental results for LiFePO4 batteries are provided, showing the capabilities of the proposal for the assessment of online SOC estimators.
  • Acceso AbiertoArtículo
    Single track orbit determination analysis for low Earth orbit with approximated J2 dynamics
    (Elsevier, 2024-09-15) Montilla García, José Manuel; Siminski, Jan A.; Vázquez Valenzuela, Rafael; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; Agencia Estatal de Investigación. España; Universidad de Sevilla. TEP945: Ingeniería Aeroespacial
    In the domain of Space Situational Awareness (SSA), the challenges related to orbit determination and catalog correlation are notably pronounced, exacerbated by data scarcity. This study introduces an initial orbit determination methodology that relies on data obtained from a single surveillance radar, with the need for fast algorithms within an operational context serving as the main design driver. The result is a linearized least-squares fitting procedure incorporating an analytically formulated approximation of the dynamics under the J2 perturbation, valid for short-term propagation. This algorithm utilizes all available observables, including range-rate, distinguishing it from other similar methods. A significant contribution of this paper is the enhancement of estimation quality by incorporating information about the object’s predicted orbital plane into the methodology, a method denoted as OPOD. The proposed methods are evaluated through a series of simulations against a classical range and angles fitting method (GTDS) to examine the effects of track length and measurement density on the quality of full state estimation, including the impact of using arcs that are too short. The OPOD methodology shows promising results throughout a wide range of scenarios.
  • Acceso AbiertoArtículo
    Climate Change and Tidal Hydrodynamics of Guadalquivir Estuary and Doñana Marshes: A Comprehensive Review
    (Multidisciplinary Digital Publishing Institute (MDPI, 2024-08) Couto, Inês; Picado, Ana; Des, Marisela; López-Ruiz, Alejandro; Díez-Minguito, Manuel; Díaz-Delgado, Ricardo; Bastos, Rita; Dias, João Miguel; Universidad de Sevilla. Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos; European Union (UE). H2020; Junta de Andalucía; Xunta de Galicia; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
    The Doñana Protected Area, Western Europe’s largest protected wetland and UNESCO World Heritage Site, is of great importance for the Spanish biodiversity. Despite its ecological value, there is a noticeable scarcity of scientific and technical information about its hydrology and expected climate change effects, as highlighted by several authors. This article reviews the existing research on the Guadalquivir River and Doñana National Park, examining the interplay between hydrodynamics, climate change scenarios, and the potential impact of the removal of the current dike which was built to limit tidal flooding. In this context, the hydrodynamic changes predicted by a hydrodynamic model were examined under both present (including the current mean sea level and the presence of the dike) and predicted future conditions (encompassing a mean sea level rise of 0.84 m and the removal of the dike). These hydrodynamic changes were assessed in terms of the maximum predicted water levels, mean velocity, amplitude, and phase of M2 and M4 tidal constituents, tidal asymmetry, and tidal prims. The results reveal that the removal of the dike and a sea level rise will have a significant impact on the protected area, resulting in the complete flooding of the Doñana national marshes during spring tides. Such changes could have negative impacts, as increased environmental alterations would require more demanding adaptation measures.