Search Results (26)

The extensive application of CubeSats in fields such as communication, remote sensing, and scientific exploration highlights their significant engineering value. With the growth of CubeSat dimensions towards 12U and beyond, their potential for engineering applications has further expanded. However, strict size constraints significantly limit the layout design space, causing difficulties in satellite system design through multiple iterations. To address these practical issues, this paper proposes an engineering-oriented layout optimization and trade-off design approach tailored specifically for 12U CubeSats, employing a hybrid optimization framework combining GRASP and NSGA-III algorithms. The proposed methodology facilitates initial feasibility analysis, informed trade-off decisions during iterative design, and detailed optimization in later stages, thereby improving design efficiency and practicality. The proposed optimization systematically explores design compromises considering conflicting objectives such as mass properties, thermal management, and spacing constraints. The ASRTU Friendship MicroSat, a 12U CubeSat, serves as a case study, with in-orbit performance validating the proposed approach. Results demonstrate that the optimized layouts effectively address complex engineering constraints, enabling satellite design teams to successfully achieve optimized layout solutions in practical engineering applications. Full article

The Biofilm Onboard Radiation Exposure Assessment Lab In Space (BOREALIS) mission is a 6U CubeSat initiative funded by the Italian Space Agency under the ALCOR program, executed through a collaboration among the School of Aerospace Engineering of Sapienza University of Rome, Interdepartmental Centre for Industrial Aerospace Research (CIRI Aerospace) of the University of Bologna and Kayser Italia Srl. BOREALIS is equipped with a lab-on-chip payload for studying the effects of microgravity and ionising radiation on microbial biofilms, which are crucial for understanding and preventing persistent infections in space environments. The satellite will operate across multiple orbits, moving from low to medium Earth orbit, to distinctly analyse the impacts of radiation separate from microgravity. The required orbital transfer not only tests the autonomy of its on-board systems in challenging conditions but also places BOREALIS among the first and few CubeSats to have ever attempted such a complex manoeuvre. This study explores the systematic application of Model-Based Systems Engineering to satellite design, from conceptualisation to trade-offs, using a tradespace analysis approach supported by Monte Carlo simulations to optimise mission configurations against performance and cost. Additionally, the adaptability of Model-Based Systems Engineering tools and the reusability of such an approach for other satellite projects are discussed, illustrating the BOREALIS mission as a case study for small mission design considering constraints and requirements. Full article

With their compact design and versatility, CubeSats have emerged as critical platforms for advancing space exploration and communication technologies. However, achieving reliable and efficient communication in the dynamic and constrained environment of low Earth orbit (LEO) remains a significant challenge. Beam-steering antenna systems offer a promising solution to address these limitations, enabling adaptive communication links with improved gain and coverage. This review article provides a comprehensive analysis of the state-of-the-art in CubeSat communication, concentrating on the latest developments in beam-steering antennas. By synthesizing the findings from recent studies, the key challenges are highlighted, including power constraints, miniaturization, and integration with CubeSat platforms. Furthermore, this paper investigates cutting-edge techniques, such as phased array systems, metasurface-based designs, and reconfigurable antennas, which pave the way for enhanced performance. This study can serve as a resource for researchers and engineers, offering insights into current trends and future opportunities for advancing CubeSat communications through innovative antenna systems. Full article

The Global Navigation Satellite System (GNSS) provides critical positioning, navigation, and timing (PNT) services worldwide, enabling a wide range of applications from everyday use to advanced scientific and military operations. The importance of Low Earth Orbit (LEO) PNT systems lies in their ability to enhance the GNSS by implementing signals in additional frequency bands, offering increased signal strength, reduced latency, and improved accuracy and coverage, particularly in challenging environments such as urban canyons or polar regions, thereby addressing the limitations of the traditional Medium Earth Orbit (MEO) GNSS. This paper details the system engineering of a novel CubeSat-based multi-regional PNT system tailored for deployment in LEO. The proposed system leverages on a miniaturized CubeSat-compatible PNT payload that includes a chip-scale atomic clock (CSAC) and relies on MEO GNSS technologies to deliver positioning and timing information across multiple regions. The findings indicate that the proposed CubeSat-based PNT system offers a viable solution for enhancing global navigation and timing services, with potential commercial and scientific applications. This work contributes to the growing body of knowledge on LEO-based PNT systems and lays the groundwork for future research and development in this rapidly evolving field. Full article

This paper analyzes the performance of an interplanetary CubeSat equipped with a hybrid propulsion system (HPS), which combines two different types of thrusters in the same deep space vehicle, in a heliocentric transfer between two assigned (Keplerian) orbits. More precisely, the propulsion system of the CubeSat considered in this work consists of a combination of a (low-performance) photonic solar sail and a more conventional solar electric thruster. In particular, the characteristics of the solar electric thruster are modeled using a recent mathematical approach that describes the performance of the miniaturized engine that will be installed on board the proposed ESA’s M-ARGO CubeSat. The latter will hopefully be the first interplanetary CubeSat to complete a heliocentric transfer towards a near-Earth asteroid using its own propulsion system. In order to simplify the design of the CubeSat attitude control subsystem, we assume that the orientation of the photonic solar sail is kept Sun-facing, i.e., the sail reference plane is perpendicular to the Sun-CubeSat line. That specific condition can be obtained, passively, by using an appropriate design of the shape of the sail reflective surface. The performance of an HPS-based CubeSat is analyzed by optimizing the transfer trajectory in a three-dimensional heliocentric transfer between two closed orbits of given characteristics. In particular, the CubeSat transfer towards the near-Earth asteroid 99942 Apophis is studied in detail. Full article

Market trends in the space sector suggest a notable increase in satellite operations and market value for the coming decade. In parallel, there has been a shift in the industrial and academic sectors from traditional Document-Based System Engineering to Model-based systems engineering (MBSE) combined with Concurrent engineering (CE) practices. Due to growing demands, the drivers behind this change have been the need for quicker and more cost-effective design processes. A key challenge in this transition remains to determine how to effectively formalize and exchange data during all design stages and across all discipline-specific tools; as representing systems through models can be a complex endeavor. For instance, during the Preliminary design (PD) phase, the integration of system models with external mathematical models for simulations, analyses, and system budgeting is crucial. The introduction of CubeSats and their standard has partly addressed the question of standardization and has aided in reducing overall development time and costs in the space sector. Nevertheless, questions about how to successfully exchange data endure. This paper focuses on formalizing a CubeSat model for use across various stages of the PD phase. The entire process is conducted with the exclusive use of open-source tools, to facilitate the transparency of data integration across the PD phases, and the overall life cycle of a CubeSat. The paper has two primary outcomes: (i) developing a generic CubeSat model using Systems modeling language (SysML) that includes data storage and visualization through the application of Unified modeling language (UML) stereotypes, streamlining in parallel information exchange for integration with various simulation and analysis tools; (ii) creating an end-to-end use case scenario within the Nanostar software suite (NSS), an open-source framework designed to streamline data exchange across different software during CE sessions. A case study from a theoretical academic space mission concept is presented as the illustration of how to utilize the proposed formalization, and it serves as well as a preliminary validation of the proposed formalization. The proposed formalization positions the CubeSat SysML model as the central data source throughout the design process. It also supports automated trade-off analyses by combining the benefits of SysML with effective data instantiating across all PD study phases. Full article

In the near future, international space agencies have planned to achieve significant milestones in investigating the utilization of Global Navigation Satellite Systems (GNSS) within and beyond the current space service volume up to their application to lunar missions. These initiatives aim to demonstrate the feasibility of GNSS navigation at lunar altitudes. Based on the outcomes of such demonstrations, dozens of lunar missions will likely be equipped with a GNSS receiver to support autonomous navigation in the lunar proximity. Relying on non-invasive, consolidated differential techniques, GNSS will enable baseline estimation, thus supporting a number of potential applications to lunar orbiters such as collaborative navigation, formation flight, orbital manoeuvers, remote sensing, augmentation systems and beyond. Unfortunately, the large dynamics and the geometry of such differential GNSS scenarios set them apart from current terrestrial and low-earth orbit use cases. These characteristics result in an increased sensitivity to measurements time misalignment among orbiters. Hence, this paper offers a review of baseline estimation methods and characterizes the divergences and limitations w.r.t. to terrestrial applications. The study showcases the estimation of the baseline length between a lunar CubeSat mission, VMMO, and the communication relay Lunar Pathfinder mission. Notably, real GNSS measurements generated by an Engineering Model of the NaviMoon receiver in the European Space Agency (ESA/ESTEC) Radio Navigation Laboratory are utilized. A radio-frequency constellation simulator is used to generate the GNSS signals in these hardware-in-the-loop tests. The performed analyses showed the invalidity of common terrestrial differential GNSS ranging techniques for space scenarios due to the introduction of significant biases. Improved ranging algorithms were proposed and their potential to cancel ranging errors common to both receivers involved was confirmed. Full article

Space exploration presents vast prospects for scientific, industrial, and economic progress. This paper introduces the MeSat mission as a pioneering approach to Mars exploration. The MeSat aims to deepen our understanding of Martian conditions and resources by employing an optimized Earth-to-Mars trajectory, enabling a comprehensive study of the Martian atmosphere and surface. The mission comprises a cargo microsatellite hosting three 6U CubeSats and two 3U CubeSats, deployed into four separate Mars orbits to form a constellation. Each CubeSat carries distinct payloads: a THz radiometer for Martian water vapor atmospheric observation, a high-resolution surface camera, a high-tech spectrometer, and a Fourier transform spectrometer (FTS) for wind speed readings. This paper includes the majority of the key parameters; however, we focus our discussion more on two aspects of this pioneering mission: the first aspect contains the proposal of four distinct payloads for the study of Mars’ atmosphere and the second aspect proposes an optimal mission design algorithm that analyzes a fuel-efficient low-thrust trajectory from Earth to Mars. Regarding the payloads, the THz radiometer requires a specific design; hence, we explain this payload in more depth; the rest of the payloads, we suggest utilizing commercially available elements for the cost-effective manufacture of a whole system. For mission trajectory optimization, the study employs a dual-step hybrid optimization algorithm (PSO-homotopy) to analyze fuel-efficient low-thrust trajectories from Earth to Mars, incorporating the ephemeris dynamics model to account for gravitational perturbations in the entire Solar System. In practical mission design, crucial factors like hyperbolic excess velocity, diverse opportunities for Earth launch and Mars rendezvous, varied propulsion systems, and time of flight (TOF) play vital roles in trajectory optimization. In summary, for the MeSat mission, we propose a comprehensive Mars environmental mission design. We consider all aspects of the mission from trajectory design to engineering detail design, since we would like to inspire future Mars missions with a complete report. Full article

As a subclass of nanosatellites, CubeSats have changed the game’s rules in the scientific research industry and the development of new space technologies. The main success factors are their cost effectiveness, relative ease of production, and predictable life cycle. CubeSats are very important for training future engineers: bachelor’s and master’s students of universities. At the same time, using CubeSats is a cost-effective method of nearest space exploration and scientific work. However, many issues are related to efficient time-limited development, software and system-level quality assurance, maintenance, and software reuse. In order to increase the flexibility and reduce the complexity of CubeSat projects, this article proposes a “hybrid” development model that combines the strengths of two approaches: the agile-a-like model for software and the waterfall model for hardware. The paper proposes a new computing platform solution, “Falco SBC/CDHM”, based on Microchip (Atmel) ATSAMV71Q21 with improved performance. This type of platform emphasizes low-cost space hardware that can compete with space-grade platforms. The paper substantiates the architecture of onboard software based on microservices and containerization to break down complex software into relatively simple components that undergraduates and graduates can handle within their Master’s studies, and postgraduates can use for scientific space projects. The checking of the effectiveness of the microservice architecture and the new proposed platform was carried out experimentally, involving the time spent on executing three typical algorithms of different algorithmic complexities. Algorithms were implemented using native C (Bare-metal) and WASM3 on FreeRTOS containers on two platforms, and performance was measured on both “Falco” and “Pi Pico” by Raspberry. The experiment confirmed the feasibility of the complex application of the “hybrid” development model and microservices and container-based architecture. The proposed approach makes it possible to develop complex software in teams of inexperienced students, minimize risks, provide reusability, and thus increase the attractiveness of CubeSat student projects. Full article

The SeaLion mission architecture team sought to create a model-based systems engineering approach to assist improving CubeSat success rates as well as for the SeaLion CubeSat project to guide an implementation for the flight software. This is important because university CubeSat teams are growing in number but often have untrained students as their core personnel. This was done using a document-as-code, or docs-as-code, approach. With this the team created tools for the systems architecture with the Mach 30 Modeling Language to create an architecture that is easy to learn and use even for newly admitted team members with little to no training. These tools generate documents via its own code for easy presentation on a local file system without any proprietary software while keeping the model content format-agnostic. Full article

AstroBio CubeSat is a mission funded by the Italian Space Agency aimed at validating novel lab-on-chip technology, that would enable the use of micro- and nanosatellites as autonomous orbiting laboratories for research in astrobiology. This 3U CubeSat is equipped with a passive magnetic attitude control system (PMACS), including permanent magnets and hysteresis strips, which allows for stabilizing the spacecraft with the longitudinal axis in the direction of the geomagnetic field vector. This work presents the process followed for the experimental characterization of the system, performed on the engineering unit of the satellite by using a Helmholtz cage facility and a spherical air-bearing to recreate environmental conditions similar to the ones experienced during the orbital motion. The hysteresis strips are characterized starting from the determination of the hysteresis loop, from which the energy dissipation per cycle and the apparent magnetic permeability are extracted. Tests performed by using the Helmholtz cage and the air-bearing facility allows for further investigating the damping torque produced by the PMACS and validating the abovementioned parameters. Numerical analysis is then used to select the number of permanent magnets which allows for achieving a pointing accuracy within an error of ${10}^{\circ }$ within 24 h from the deployment. The analysis of the flight data supports the results obtained from the experimental test campaigns, confirming the effectiveness of the proposed methods and of the PMACS design. Full article

On 1 April 2022, the AlfaCrux CubeSat was launched by the Falcon 9 Transporter-4 mission, the fourth SpaceX dedicated smallsat rideshare program mission, from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida into a Sun-synchronous orbit at 500 km. AlfaCrux is an amateur radio and educational mission to provide learning and scientific benefits in the context of small satellite missions. It is an opportunity for theoretical and practical learning about the technical management, systems design, communication, orbital mechanics, development, integration, and operation of small satellites. The AlfaCrux payload, a software-defined radio hardware, is responsible for two main services, which are a digital packet repeater and a store-and-forward system. In the ground segment, a cloud-computing-based command and control station has been developed, together with an open access online platform to access and visualize the main information of the AlfaCrux telemetry and user data and experiments. It also becomes an in-orbit database reference to be used for different studies concerned with, for instance, radio propagation, attitude reconstruction, data-driven calibration algorithms for satellite sensors, among others. In this context, this paper describes the AlfaCrux mission, its main subsystems, and the achievements obtained in the early orbit phase. Scientific and engineering assessments conducted with the spacecraft operations to tackle unexpected behaviors in the ground station and also to better understand the space environment are also presented and discussed. Full article

The ${}^3$Cat-4 mission aims at demonstrating the capabilities of a CubeSat to perform Earth Observation (EO) by integrating a combined GNSS-R and Microwave Radiometer payload into a 1-Unit CubeSat. One of the greatest challenges is the design of an antenna that respects the 1-Unit CubeSat envelope while operating at the different frequency bands: Global Positioning System (GPS) L1 and Galileo E1 band (1575 MHz), GPS L2 band (1227 MHz), and the microwave radiometry band (1400–1427 MHz). Moreover, it requires between 8 and 12 dB of directivity depending on the band whilst providing at least 10 dB of front-to-back lobe ratio in L1 and L2 GPS bands. After a trade-off analysis on the type of antenna that could be used, a helix antenna was found to be the most suitable option to comply with the requirements, since it can be stowed during launch and deployed once in orbit. This article presents the antenna design from a radiation performance point of view starting with a theoretical analysis, then presenting the numerical simulations, the measurements in an Engineering Model (EM), and finally the final design and performance of the Flight Model (FM). Full article

The compact, standardised form factor of CubeSats allows for the use of commercial off-the-shelf components, reducing traditional barriers to entry, such as cost and development time. More than 1500 of these small spacecraft have been launched in the past 20 years, with improving capabilities that enable a wide range of mission profiles. The Educational Irish Research Satellite, EIRSAT-1, is a CubeSat being developed by a student-led team with goals that span education, technology demonstration and science. A comprehensive mission test plan, in which in-flight conditions are simulated, has been developed for EIRSAT-1 and implemented using an engineering qualification model of the spacecraft. In addition to verifying 41 mission requirements, the successful execution of the mission test plan established that the full satellite system can perform the intended mission. Mission testing also proved to be an invaluable tool to prepare for launch and operations, providing the team with a more complete understanding of the satellite’s expected on-orbit behaviour. This work presents a detailed description of the mission test planning process and implementation, as well as key results and lessons learned. In doing so, this work aims to improve the on-orbit reliability of CubeSats by disseminating resources and good practice around mission testing. Full article

CubeSats facilitate rapid development and deployment of missions for educational, technology demonstration, and scientific purposes. However, they are subject to a high failure rate, with a leading cause being the lack of system-level verification. The Educational Irish Research Satellite (EIRSAT-1) is a CubeSat mission under development in the European Space Agency’s (ESA) Fly Your Satellite! Programme. EIRSAT-1 is a 2U CubeSat with three novel payloads and a bespoke antenna deployment module, which all contribute to the complexity of the project. To increase the likelihood of mission success, a prototype model philosophy is being employed, where both an engineering qualification model (EQM) and a flight model of EIRSAT-1 are being built. Following the assembly of the EQM, the spacecraft underwent a successful full functional test and month-long mission test. An environmental test campaign in ESA Education Office’s CubeSat Support Facility was then conducted with the EQM where both vibration and thermal verification test campaigns were performed. The focus of this paper is the thermal testing and verification of the EIRSAT-1 EQM. Over three weeks, the EQM was subjected to one non-operational cycle, three and a half operational cycles, and a thermal balance test in a thermal vacuum chamber. After dwelling at each temperature extreme, functional tests were performed to investigate the performance of the spacecraft in this space representative environment. The approach to planning and executing the thermal testing is described in detail including the documentation required, set up of the test equipment, and determination of the test levels. Overall, the campaign demonstrated that the mission can successfully operate in a space environment similar to that expected in orbit, despite encountering a number of issues. These issues included a payload displaying anomalous behaviour at cold temperatures and needing to redefine test levels due to an insufficient understanding of the internal dissipation in the spacecraft. A total of two major and three minor non-conformances were raised. Crucially, these issues could not have been found without thermal testing, despite the comprehensive ambient tests performed. The main results and lessons learned during this thermal test campaign are presented with the aim of guiding future missions on optimal approaches in organising and executing the thermal testing of their CubeSats. Full article