Browsing by Author "Dalbins, Janis"

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Aspects of nanospacecraft design for main-belt sailing voyage
(2021-05) Iakubivskyi, Iaroslav; Mačiulis, Laurynas; Janhunen, Pekka; Dalbins, Janis; Noorma, Mart; Slavinskis, Andris
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
We present a detailed mechanical and thermal analysis of a stand-alone nanospacecraft that performs asteroid flybys in the main asteroid belt (2.75 AU) and one Earth flyby at the end of the mission to return the gathered data. A fleet of such nanospacecraft (10 kg) has been proposed as part of the Multi-Asteroid Touring mission concept, a nearly propellantless mission where the electric solar wind sail (E-sail) is used for primary propulsion. The fleet makes flybys of thus far poorly characterised asteroid populations in the main belt and downlinks scientific data during the returning Earth flyby. The spacecraft size is close to a three-unit cubesat with a mass of less than 6 kg. The spacecraft is designed for a 3.2-year round trip. A 20-km-long E-sail tether is used. A remote unit is attached to the tether’s tip and stowed inside the spacecraft before the E-sail commissioning. The remote unit is slightly smaller than a one-unit cubesat with a mass of approximately 750 g. With an electrospray thruster, it provides angular momentum during tether deployment and spin-rate management while operating the E-sail. The selection of materials and configurations is optimised for thermal environment as well as to minimise the mass budget. This paper analyses the main spacecraft and remote-unit architectures along with deployment and operation strategies from a structural point of view, and thermal analysis for both bodies.
Coulomb drag propulsion experiments of ESTCube-2 and FORESAIL-1
(2020-12) Iakubivskyi, Iaroslav; Janhunen, Pekka; Praks, Jaan; Allik, Viljo; Bussov, Kadri; Clayhills, Bruce; Dalbins, Janis; Eenmäe, Tõnis; Ehrpais, Hendrik; Envall, Jouni; Haslam, Sean; Ilbis, Erik; Jovanovic, Nemanja; Kilpua, Emilia; Kivastik, Joosep; Laks, Jürgen; Laufer, Philipp; Merisalu, Maido; Meskanen, Matias; Märk, Robert; Nath, Ankit; Niemelä, Petri; Noorma, Mart; Mughal, Muhammad Rizwan; Nyman, Samuli; Pajusalu, Mihkel; Palmroth, Minna; Paul, Aditya Savio; Peltola, Tatu; Plans, Mathias; Polkko, Jouni; Islam, Quazi Saimoon; Reinart, Anu; Riwanto, Bagus; Sammelselg, Väino; Sate, Janis; Sünter, Indrek; Tajmar, Martin; Tanskanen, Eija; Teras, Hans; Toivanen, Petri; Vainio, Rami; Väänänen, Mika; Slavinskis, Andris
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This paper presents two technology experiments – the plasma brake for deorbiting and the electric solar wind sail for interplanetary propulsion – on board the ESTCube-2 and FORESAIL-1 satellites. Since both technologies employ the Coulomb interaction between a charged tether and a plasma flow, they are commonly referred to as Coulomb drag propulsion. The plasma brake operates in the ionosphere, where a negatively charged tether deorbits a satellite. The electric sail operates in the solar wind, where a positively charged tether propels a spacecraft, while an electron emitter removes trapped electrons. Both satellites will be launched in low Earth orbit carrying nearly identical Coulomb drag propulsion experiments, with the main difference being that ESTCube-2 has an electron emitter and it can operate in the positive mode. While solar-wind sailing is not possible in low Earth orbit, ESTCube-2 will space-qualify the components necessary for future electric sail experiments in its authentic environment. The plasma brake can be used on a range of satellite mass classes and orbits. On nanosatellites, the plasma brake is an enabler of deorbiting – a 300-m-long tether fits within half a cubesat unit, and, when charged with -1 kV, can deorbit a 4.5-kg satellite from between a 700- and 500-km altitude in approximately 9–13 months. This paper provides the design and detailed analysis of low-Earth-orbit experiments, as well as the overall mission design of ESTCube-2 and FORESAIL-1.
Electric Sail Test Cube–Lunar Nanospacecraft, ESTCube-LuNa: Solar Wind Propulsion Demonstration Mission Concept
(2024-03-14) Slavinskis, Andris; Palos, Mario F.; Dalbins, Janis; Janhunen, Pekka; Tajmar, Martin; Ivchenko, Nickolay; Rohtsalu, Agnes; Micciani, Aldo; Orsini, Nicola; Moor, Karl-Mattias; Kuzmin, Sergei; Bleiders, Marcis; Donerblics, Marcis; Ofodile, Ikechukwu; Kütt, Johan; Eenmae, Tonis; Allik, Viljo; Viru, Jaan; Halapuu, Pätris; Kristmann, Katriin; Sate, Janis; Briede, Endija; Anger, Marius; Aas, Katarina; Plonis, Gustavs; Teras, Hans; Allaje, Kristo; Vaivads, Andris; Niccolai, Lorenzo; Bassetto, Marco; Mengali, Giovanni; Toivanen, Petri; Iakubivskyi, Iaroslav; Pajusalu, Mihkel; Tamm, Antti
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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.