CubeSat Design Research Articles

Electric Sail Test Cube–Lunar Nanospacecraft, ESTCube-LuNa: Solar Wind Propulsion Demonstration Mission Concept

The electric solar wind sail, or E-sail, is a propellantless interplanetary propulsion system concept. By deflecting solar wind particles off their original course, it can generate a propulsive effect with nothing more than an electric charge. The high-voltage charge is applied to one or multiple centrifugally deployed hair-thin tethers, around which an electrostatic sheath is created. Electron emitters are required to compensate for the electron current gathered by the tether. The electric sail can also be utilised in low Earth orbit, or LEO, when passing through the ionosphere, where it serves as a plasma brake for deorbiting—several missions have been dedicated to LEO demonstration. In this article, we propose the ESTCube-LuNa mission concept and the preliminary cubesat design to be launched into the Moon’s orbit, where the solar wind is uninterrupted, except for the lunar wake and when the Moon is in the Earth’s magnetosphere. This article introduces E-sail demonstration experiments and the preliminary payload design, along with E-sail thrust validation and environment characterisation methods, a cis-lunar cubesat platform solution and an early concept of operations. The proposed lunar nanospacecraft concept is designed without a deep space network, typically used for lunar and deep space operations. Instead, radio telescopes are being repurposed for communications and radio frequency ranging, and celestial optical navigation is developed for on-board orbit determination.

CORTO: The Celestial Object Rendering TOol at DART Lab

The Celestial Object Rendering TOol (CORTO) offers a powerful solution for generating synthetic images of celestial bodies, catering to the needs of space mission design, algorithm development, and validation. Through rendering, noise modeling, hardware-in-the-loop testing, and post-processing functionalities, CORTO creates realistic scenarios. It offers a versatile and comprehensive solution for generating synthetic images of celestial bodies, aiding the development and validation of image processing and navigation algorithms for space missions. This work illustrates its functionalities in detail for the first time. The importance of a robust validation pipeline to test the tool’s accuracy against real mission images using metrics like normalized cross-correlation and structural similarity is also illustrated. CORTO is a valuable asset for advancing space exploration and navigation algorithm development and has already proven effective in various projects, including CubeSat design, lunar missions, and deep learning applications. While the tool currently covers a range of celestial body simulations, mainly focused on minor bodies and the Moon, future enhancements could broaden its capabilities to encompass additional planetary phenomena and environments.

GREATCUBE+: conceptual design tool for CubeSat’s design

CubeSats are a type of spacecraft which have become popular since the early 2000. They are known for their quick development time and low cost, when comparing them to larger satellites. However, there is a significant drawback which has been recorded during these years of operations, namely an high failure rate which turns almost half of them into space debris. The reasons behind these malfunctions are often attributed to flawed spacecraft design choices or failures of commercial off-the-shelf (COTS) products. To improve the design of CubeSats, several software tools for performing the conceptual design have been proposed. These tools are often limited in their capabilities and are not suitable for all types of CubeSat missions. To address this issue, the University of Applied Sciences Wiener Neustadt (FHWN) in cooperation with Technische Universität Dresden is developing a software tool called GREATCUBE+. Its goal is to increase the success rate of CubeSats by providing a satellite model which is composed of commercial-off-the-shelf (COTS) products backed up by empirical heritage, analytical proof, and numerical analysis. One of the main features of this tool is the ability of dealing with different typologies of payloads. GREATCUBE+ has been validated with various successful CubeSat missions and it provides design solutions with an accuracy of above 90% when it comes to CubeSat weights and volumes. Using this software, CubeSat design teams can proceed from the conceptual development to the testing and assembly phases quicker, hoping to result in higher quality CubeSats and fewer failures.

Decision making for multi‐objective problems: Mean and median metrics

AbstractWhen dealing with problems with more than two objectives, sophisticated multi‐objective optimization algorithms might be needed. Pareto optimization, which is based on the concept of dominated and non‐dominated solutions, is the most widely utilized method when comparing solutions within a multi‐objective setting. However, in the context of optimization, where three or more objectives are involved, the effectiveness of Pareto dominance approaches to drive the solutions to convergence is significantly compromised as more and more solutions tend to be non‐dominated by each other. This in turn reduces the selection pressure, especially for algorithms that rely on evolving a population of solutions such as evolutionary algorithms, particle swarm optimization, differential evolution, etc. The size of the non‐dominated set of trade‐off solutions can be quite large, rendering the decision‐making process difficult if not impossible. The size of the non‐dominated solution set increases exponentially with an increase in the number of objectives. This paper aims to expand a framework for coping with many/multi‐objective and multidisciplinary optimization problems through the introduction of a min‐max metric that behaves like a median measure that can locate the center of a data set. We compare this metric to the Chebyshev norm L_∞ metric that behaves like a mean measure in locating the center of a data set. The median metric is introduced in this paper for the first time, and unlike the mean metric is independent of the data normalization method. These metrics advocate balanced, natural, and minimum compromise solutions about all objectives. We also demonstrate and compare the behavior of the two metrics for a Tradespace case study involving more than 1200 CubeSat design alternatives identifying a manageable set of potential solutions for decision‐makers.

Development of a deployable Synthetic Aperture Radar antenna for a nanosatellite conceptual design

For a real-time maritime surveillance application in the extended territorial waters of New Zealand, this work aims to develop a viable concept design for a deployable Synthetic Aperture Radar (SAR) antenna to fit in a CubeSat design space. To trade off a large antenna aperture, which is essential to enhance SAR performance, and a high packaging efficiency, potentially ≤ 12U, a 4 m x 0.3 m reflectarray with a stiff-and-flexible and novel passive deployable system is selected as the most promising solution for this application. A High Strain Composite (HSC) structure with a shallow “tape-measure” inspired shape is presented to support the SAR reflectarray and compactly stow it through a rollable deployment system. The release of the elastic energy stored in the coiled structure will enable the deployment, and the structural stiffness will be provided by a boundary condition that maintains the naturally curved cross-section during stowage. With this design constraint, the transition zone (ploy region) that develops between the stowed and deployed state may significantly impact the stowage capabilities. The elastic behaviour of the structure will be analytically studied in terms of the change of curvatures and bending stiffness as they dominate the deformed shape in the coiling process. Existing analytical models that predict the ploy regions are considered to estimate the natural ploy length and the equivalent coil diameter. Finite Element (FE) models are developed to compare the analytical models and explore the stress field generated within the ploy region when the length of this region is forced to be shorter than the natural ploy length. FE model observations and data are also used to improve the analytical model that describes the deformed shape by imposing non-uniform boundary conditions on the curvatures’ field distribution within the ploy region.

Can Communities Produce Complex Technology? Looking Into Space for Insight

This article examines a community producing complex space technology. We attempt to highlight which aspects of the community’s activities can help democratize high-tech development while providing a context for similar cases involved in developing and manufacturing nonhigh-technological artefacts. We discuss how this has been made possible by using a technology-determined organizational approach based on the CubeSat open platform infrastructure, blending formal and hands-on education, open communication, specific recruitment and working practices, and a genuine passion for technology. We identify as critical enablers for community-based collaborative development of space technology the open-source architecture standard called CubeSat Design Specifications, the modularization of work in subsystems and between different organizations, and the open and participatory approach work tasks distribution and decision making. Moreover, we argue that the digital/informational aspect of this technology allows the community to implement organizational practices that resemble how open-source movements over the internet produce complex digital artefacts like Wikipedia or Linux. ESTCube can shed light on community-driven complex technology development, providing lessons on what a democratized version of high technology would resemble and how open and digitalized technology can help develop the capacities of a community.

Conceptual Structural Design and Comparative Power System Analysis of Ozone Dynamics Investigation Nano-satellite (ODIN)

The Ozone Dynamics Investigation Nano-Satellite (ODIN) is a CubeSat design proposed by Chungnam National University as contribution to the CubeSat Competition 2019 sponsored by the Korean Aerospace Research Institute (KARI). The main objectives of ODIN are (1) to observe the polar ozone column density (latitude range of 60° to 80° in both hemispheres) and (2) to investigate the chemical dynamics between stratospheric ozone and ozone depleting substances (ODSs) through spectroscopy of the terrestrial atmosphere. For the operation of ODIN, a highly efficient power system designed for the specific orbit is required. We present the conceptual structural design of ODIN and an analysis of power generation in a sun synchronous orbit (SSO) using two different configurations of 3U solar panels (a deployed model and a non-deployed model). The deployed solar panel model generates 189.7 W through one day which consists of 14 orbit cycles, while the non-deployed solar panel model generates 152.6 W. Both models generate enough power for ODIN and the calculation suggests that the deployed solar panel model can generate slightly more power than the non-deployed solar panel model in a single orbit cycle. We eventually selected the non-deployed solar panel model for our design because of its robustness against vibration during the launch sequence and the capability of stable power generation through a whole day cycle.

Requirements for CubeSat on-board sensors for identification of design and inertial characteristics

In this paper, we discuss requirements formulation for CubeSat on-board sensors characteristics for solving identification problem. The problem is to estimate design and inertial parameters of CubeSat-format nanosatellite using on-board sensor measurements. Identification problem for CubeSats becomes more and more actual every year because CubeSat design becomes more complicated due to complex missions requirements. Modern CubeSats can be equipped with deployable solar panels, propulsion units and different types of transformable structures. This fact makes it necessary to study CubeSats as bodies with variable inertial and design characteristics. In this article the design parameter is fuel level in the CubeSat propulsion system and inertial parameters are inertial coefficients (inertia moments analog). We study requirements formulation for magnetometer and angular rate sensor, as this combination of sensors is the most popular in CubeSat development. The main idea of this paper is to study the sensitivity of measurements to estimated parameters. This sensitivity depends on time and measurement noise, large sensitivity leads to low estimation error. We conducted a numerical study and provide an algorithm which allows to define sensitivity-time-noise dependence for each type of sensors and formulate the requirements for their characteristics.

Attitude determination by unscented Kalman filter and solar panels as sun sensor

CubeSats have became a common platform for education and technology demonstration. To overcome restrictions on CubeSat design, the Attitude Determination and Control System can use the photovoltaic panels to replace sun sensor. This work presents an attitude estimation method based on an unscented Kalman filter, using low cost gyroscope and magnetometer sensors and solar panels as a sun sensor. Data are simulated considering the influence of the Earth albedo on solar panels, and results are compared to those obtained by an extended Kalman filter.

Miniaturized Solutions for CubeSat Servicing and Safety Requirements

Small spacecraft require systems to facilitate safe preflight and launch operations. These include access ports to test software, charge batteries, and monitor spacecraft health after assembly, as well as inhibits to prevent inadvertent operation during servicing, integration, transport, and launch. For CubeSats, the requirements for these features are primarily governed by the CubeSat Design Specification (CDS). The size, weight, and cost of existing, off-the-shelf access port, inhibit, and remove-before-flight implementations can be prohibitive for low-budget, miniaturized spacecraft. This article aims to reduce the size, weight, and cost of CDS-required servicing and safety features. This is achieved by integrating these features into a single system using off-the-shelf, consumer-scale electrical components, including a type-B universal serial bus (USB) mini connector and an FTDI USB to multiserial protocol integrated circuit.

Structural Dynamics Analysis of 3-U CubeSat

The development of CubeSats has been advanced significantly during the past two decades for both scientific research and industrial purposes. During the manufacturing process, every CubeSat must satisfy various system requirements in which the structural analysis is one of the most vital necessity in order to assure a normal operation of the CubeSat during its working time in space. In the conceptual design phase, structural dynamics is a mandatory step to determine the natural frequencies of individual bodies, the deformation and stress induced at the corresponding vibration modes to prevent structural failure. In this work, IGOSat, a 3-Unit CubeSat, which was developed at the Paris Diderot University is exanimated in term of modal, harmonic response, and random vibration analysis at the time of ground testing as well as the launching phase using ANSYS software. These numerical simulations conducted according to the CubeSat Design Specification and the system requirements of QB50 project. The minimum natural frequency of the CubSat obtained to be 363.17 (Hz), which passed the required frequency of 90 (Hz). Moreover, the Harmonic and Random vibration analyses indicate that the peak response of normal stress, as well as deformation values obtained, are far lesser compared to the yield strength of the frame structure and subsystem materials. Hence, our numerical analysis found that the CubeSat remains intact during the launch environment.

Mission Capability Assessment of 3D Printing Cubesats

With the successful development of integrated technologies, many spacecraft subsystems have been continuously miniaturized, and CubeSats have gradually become the main executors of space science exploration missions. It is a new challenge to combine the CubeSat design with 3D printing. Compared with traditional manufacturing through machining, 3D printing technology has several advantages including short period of manufacturing, high accuracy in manufacturing small parts and low cost. The research task of this paper is a LEO (Low Earth Orbit) CubeSat mission, with a maximum acceleration of 5 g during the launch process, the internal operating temperature range of the CubeSat is from 0 to 40 °C, external temperature from -80 to 100 °C. The environmental factors were fully considered in the CubeSat design process, the impact load received during the CubeSat launch process and the working environment after reaching orbit were simulated and analyzed by ANSYS after the design parameters were obtained to verify the feasibility of the design.

Selective Laser Melting of a 1U CubeSat structure. Design for Additive Manufacturing and assembly

The aerospace industry has used Additive Manufacturing (AM) since its beginnings in the ‘80s because of its unique capabilities. The present work shows a re-designing and the manufacturing via AM of the structural sub-system of a CubeSat from the nanosatellite class. Specifically, a 1U CubeSat design proposal has been developed according to Design for Additive Manufacturing (DFAM) guidelines, considering the consolidation of the parts for reducing and/or avoiding the assembly issues. A configuration made of only two parts has been successfully fabricated via Selective Laser Melting (SLM) technology. AM capabilities allowed to integrate a hinge mechanism in the design, making the resulting structure an already-assembled one. Moreover, the design exhibits snap-fit features in order to get rid of fasteners. The increased complexity of the parts due to the integration of the additional snap-fit features results in no manufacturing issues due to the AM capability to manage shape complexity. This work points AM out as a key technology allowing for a drastic reduction of the part count for a mechanical system, taking Design for Assembly (DFA) guidelines to the extreme. It underlines the need to consider AM-related constrains already in the design phase, such as the clearance and the shape of the hinge and the snap joint matching SLM specific constraints such as support structures design and removal planning, part orientation in the building platform, and hollowing out for powder removal.

Resource Efficient Process Chain Development of a Modular CubeSat Spaceframe

A CubeSat is a 10×10×10 cm cube that can weigh up to 1.33 kg. This design offers a less expensive alternative for space enthusiasts to explore the cosmos, even though the total weight is very limited. For a CubeSat to be allowed to launch, it must adhere to certain specifications outlined in the CubeSat Design Specifications document. This places several restrictions on the satellite in terms of weight, size and center of gravity, and innovative solutions need to be explored during integration to meet these specifications. Having a spaceframe that can easily be assembled and disassembled will help smooth out the integration stage and save a significant time that can then be allocated elsewhere in the developmental stages. The increasing relevance of resource efficient manufacturing is prevalent through the continually rising costs of resources and energy. In order to stay competitive, manufacturers must develop resource efficient process chains to gain an advantage in the market. This study focused on developing a resource efficient process chain to manufacture a modular CubeSat spaceframe. This spaceframe must adhere to the CubeSat Design specifications, as well as meet the customer’s needs. A unique assembly process was designed that eliminated the need for screws structure together. Instead the spaceframe relies on interference fits, and utilizes the unique deployment method of the Poly-Picosatellite Orbital Deployer to ensure that the assembly does not fail. A material selection procedure was utilized, along with resource efficient manufacturing process chains to develop a CubeSat structure that is very cost effective to produce, easily assembled and disassembled and weighed less than most of the market leading CubeSat structures.

A new CubeSat design with reconfigurable multi-band radios for dynamic spectrum satellite communication networks

Small satellites, or CubeSats, are envisioned as a promising solution for future satellite communication networks because of their low costs and short deployment cycle. Currently, CubeSats communicate at conventionally allocated satellite communication frequencies. However, with the increase in the number of CubeSats, CubeSat-enabled communication systems, and many new use cases, new spectrum bands and a more efficient spectrum usage are needed. In this paper, a novel CubeSat design with reconfigurable multi-band radios for communication in dynamic frequencies is proposed.The multi-band radio design is realized by two complementary approaches, namely, an electronics-based and a photonics-based approach. The multi-band communication covers a wide range from radio frequencies (2–30 GHz), millimeter wave (30–300 GHz), Terahertz band (up to 10 THz), and optical frequencies (with typical bands of 850 nm/350 THz, 1300 nm/230 THz, and 1550 nm/193 THz). A thorough link budget analysis is conducted to demonstrate the potential of the proposed multi-band architecture for space information networks. Key parameters in the satellite constellation design are investigated to explore the feasibility of deployment at different altitudes in the exosphere orbit (500 km and above). A continuous global coverage is demonstrated to serve the Internet of Space Things, a new paradigm for next generation satellite communication networks.

A Reliability Engineering Approach for Managing Risks in CubeSats

Besides large-scale space missions, the spread of CubeSats for a variety of applications is increasingly requiring the development of systematic approaches for risk management. Being these applications are based on components with low TRL (Technology Readiness Level) or with limited performance data, it is required to define approaches which ensure a systematic perspective. This paper aims to present a reliability engineering approach based on FMECA (Failure Mode, Effects, and Criticality Analysis) to manage CubeSat reliability data and prioritize criticalities early in the design phase. The approach firstly proposes an alpha-numeric coding system to support the identification and labeling of failure modes for typical CubeSats’ items. Subsequently, each FMECA coefficient (i.e., Severity, Occurrence, Detectability) has been linked to the CubeSat’s structural properties, reducing subjectivity by means of techno-centric proxy indicators. The approach has been validated in the design phases of a 6-Units university CubeSat for the observation of M-Dwarf stars and binary systems. The performed analysis supported the design process and allowed to identify the major criticalities of the CubeSat design, as demonstrated in the extended case study included in the paper. The formalized method could be applied to design procedures for nano-satellites, as well as being expanded for research and development in a variety of space missions.

Analysis and Synthesis of Motion of Aerodynamically Stabilized Nanosatellites of the CubeSat Design

The motion of aerodynamically stabilized nanosatellites of the CubeSat design is studied. The features of the nanosatellites behavior in low orbits are conditioned both by the atmospheric effects and their own mass and inertial characteristics: the lifetime of nanosatellites is shorter, while the angular acceleration generated by the aerodynamic moment is much higher as compared with big satellites having large mass. CubeSats may experience resonance modes of motion caused by the shape factor of a rectangular parallelepiped. In addition, the existing commercial CubeSat deployers often generate large initial angular velocities that are random in nature. The conditions that cause the specific features of the CubeSat motion are considered and analyzed. A probabilistic approach to choosing their mass and inertial characteristics is proposed. The problems of motion stabilization are studied, and recommendations are formulated on the design of aerodynamically stabilized CubeSats with a passive/active magnetic damping system.

Анализ и синтез движения аэродинамически стабилизированных космических аппаратов нанокласса формата CUBESAT

Анализ и синтез движения аэродинамически стабилизированных космических аппаратов нанокласса формата CUBESAT

Smallsat Rational Design

This paper is devoted to the study of CubeSat rational designing technique. The CubeSat design process is comprised of choice of its trajectory, determination of components and main parameters of its systems, development of external and internal layouts, determination of the number of satellite-born antennas and their main characteristics. The potential of CubeSat has prompted the scientific community to rethink the existing spacecraft technologies and think about how to make them suitable for CubeSats. In terms of specialization of engineering works during Smallsat development, was formulated concept of the design process and recognized physical relationships to find some optimal design solution about compatibility of basic parameters and characteristics. The purpose of Smallsat rational design is to create a project of a vehicle for which the value of the selected criterion is close to the maximum or minimum value. As a result, the design algorithm version was making. The described method of rational design, of course, does not deny the process of intuitive creative thinking. This process reveals itself in assumptions and development of reference versions, as well as in ballistic design.

SWEET CubeSat – Water detection and water quality monitoring for the 21st century

Water scarcity and contamination of clean water have been identified as major challenges of the 21st century, in particular for developing countries. According to the International Water Management Institute, about 30% of the world's population does not have reliable access to clean water. Consequently, contaminated water contributes to the death of about 3 million people every year, mostly children. Access to potable water has been proven to boost education, equality and health, reduce hunger, as well as help the economy of the developing world. Currently used in-situ water monitoring techniques are sparse, and often difficult to execute. Space-based instruments will help to overcome these challenges by providing means for water level and water quality monitoring of medium-to-large sweet (fresh) water reservoirs. Data from hyperspectral imaging instruments on past and present governmental missions, such as Envisat and Aqua, has been used for this purpose. However, the high cost of large multi-purpose space vessels, and the lack of dedicated missions limits the continuous monitoring of inland and coastal water quality. The proposed CubeSat mission SWEET (Sweet Water Earth Education Technologies) will try to fill this gap. The SWEET concept is a joint effort between the Technical University of Munich, the German Space Operations Center and the African Steering Committee of the IAF. By using a novel Fabry-Perot interferometer-based hyperspectral imager, the mission will deliver critical data directly to national water resource centers in Africa with an unmatched cost per pixel ratio and high temporal resolution. Additionally, SWEET will incorporate education of students in CubeSat design and water management. Although the aim of the mission is to deliver local water quality and water level data to African countries, further coverage could be achieved with subsequent satellites. Finally, a constellation of SWEET-like CubeSats would extend the coverage to the whole planet, delivering daily data to ensure reliable access to clean water for millions of people worldwide.