scholarly journals In-orbit demonstration of an iodine electric propulsion system

Nature ◽  
2021 ◽  
Vol 599 (7885) ◽  
pp. 411-415
Author(s):  
Dmytro Rafalskyi ◽  
Javier Martínez Martínez ◽  
Lui Habl ◽  
Elena Zorzoli Rossi ◽  
Plamen Proynov ◽  
...  

AbstractPropulsion is a critical subsystem of many spacecraft1–4. For efficient propellant usage, electric propulsion systems based on the electrostatic acceleration of ions formed during electron impact ionization of a gas are particularly attractive5,6. At present, xenon is used almost exclusively as an ionizable propellant for space propulsion2–5. However, xenon is rare, it must be stored under high pressure and commercial production is expensive7–9. Here we demonstrate a propulsion system that uses iodine propellant and we present in-orbit results of this new technology. Diatomic iodine is stored as a solid and sublimated at low temperatures. A plasma is then produced with a radio-frequency inductive antenna, and we show that the ionization efficiency is enhanced compared with xenon. Both atomic and molecular iodine ions are accelerated by high-voltage grids to generate thrust, and a highly collimated beam can be produced with substantial iodine dissociation. The propulsion system has been successfully operated in space onboard a small satellite with manoeuvres confirmed using satellite tracking data. We anticipate that these results will accelerate the adoption of alternative propellants within the space industry and demonstrate the potential of iodine for a wide range of space missions. For example, iodine enables substantial system miniaturization and simplification, which provides small satellites and satellite constellations with new capabilities for deployment, collision avoidance, end-of-life disposal and space exploration10–14.

Aerospace ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 22
Author(s):  
Dillon O’Reilly ◽  
Georg Herdrich ◽  
Darren F. Kavanagh

Over 2500 active satellites are in orbit as of October 2020, with an increase of ~1000 smallsats in the past two years. Since 2012, over 1700 smallsats have been launched into orbit. It is projected that by 2025, there will be 1000 smallsats launched per year. Currently, these satellites do not have sufficient delta v capabilities for missions beyond Earth orbit. They are confined to their pre-selected orbit and in most cases, they cannot avoid collisions. Propulsion systems on smallsats provide orbital manoeuvring, station keeping, collision avoidance and safer de-orbit strategies. In return, this enables longer duration, higher functionality missions beyond Earth orbit. This article has reviewed electrostatic, electrothermal and electromagnetic propulsion methods based on state of the art research and the current knowledge base. Performance metrics by which these space propulsion systems can be evaluated are presented. The article outlines some of the existing limitations and shortcomings of current electric propulsion thruster systems and technologies. Moreover, the discussion contributes to the discourse by identifying potential research avenues to improve and advance electric propulsion systems for smallsats. The article has placed emphasis on space propulsion systems that are electric and enable interplanetary missions, while alternative approaches to propulsion have also received attention in the text, including light sails and nuclear electric propulsion amongst others.


Author(s):  
Roberto Capata ◽  
Luca Marino ◽  
Enrico Sciubba

In recent years, a renewed interest in the development of unmanned air vehicles (UAVs) led to a wide range of interesting applications in the fields of reconnaissance and surveillance. In these types of mission, the noise produced by propeller driven UAVs is a major drawback, which can be partially solved by installing an electric motor to drive the propeller. The evolution of high performance brushless motors makes electric propulsion particularly appealing, at least for small and medium size UAVs. All electric propulsion systems developed to date are though penalized by the limited range/endurance that can be provided by a reasonably sized battery pack. In this paper we propose a hybrid propulsion system based on a recently developed, high efficiency microturbine which can be used to power an electric generator, thus providing a significant range/mission time extension. The UMTG is undergoing operational testing in our Laboratory, to identify its most suitable configuration and to improve its performance: a new compact regenerative combustion chamber was developed and several tests were performed to reduce its weight and size so as to increase the vehicle payload. In a high range/endurance mission the ultramicro turbine drives the electrical motor that powers the propeller only during the cruise phase (the so-called “transfer to target”), while in the final approach, in which a quiet flight attitude is mandatory, a (smaller) battery pack drives the motor directly and the UMTG is turned off. The mission requirements considered for the preliminary design of the UAV consist of a long endurance (> 12 hours) step, with a cruise speed of 33.3 m/s and a dash speed of 45 m/s at an altitude of 5000 meters. The maximum take-off weight is 500 N, with a payload of 80 N. Under the above assumptions, a flying wing configuration for the UAV was defined, with a length of 1.6 meters and a span of 2.5 meters. A system of elevons assures the pitch and roll motion while a double vertical tail, in which a pusher propeller is lodged, guarantees the yaw stability and control.


Aerospace ◽  
2020 ◽  
Vol 7 (6) ◽  
pp. 67 ◽  
Author(s):  
George-Cristian Potrivitu ◽  
Yufei Sun ◽  
Muhammad Wisnuh Aggriawan bin Rohaizat ◽  
Oleksii Cherkun ◽  
Luxiang Xu ◽  
...  

The age of space electric propulsion arrived and found the space exploration endeavors at a paradigm shift in the context of new space. Mega-constellations of small satellites on low-Earth orbit (LEO) are proposed by many emerging commercial actors. Naturally, the boom in the small satellite market drives the necessity of propulsion systems that are both power and fuel efficient and accommodate small form-factors. Most of the existing electric propulsion technologies have reached the maturity level and can be the prime choices to enable mission versatility for small satellite platforms in Earth orbit and beyond. At the Plasma Sources and Applications Centre/Space Propulsion Centre (PSAC/SPC) Singapore, a continuous effort was dedicated to the development of low-power electric propulsion systems that can meet the small satellites market requirements. This review presents the recent progress in the field of electric propulsion at PSAC/SPC Singapore, from Hall thrusters and thermionic cathodes research to more ambitious devices such as the rotamak-like plasma thruster. On top of that, a review of the existing vacuum facilities and plasma diagnostics used for electric propulsion testing and characterization is included in the present research.


2014 ◽  
Vol 02 (01) ◽  
pp. 16-35 ◽  
Author(s):  
R. Capata ◽  
L. Marino ◽  
E. Sciubba

In recent years, renewed interest in the development of unmanned aerial vehicles (UAVs) has led to a wide range of interesting applications in reconnaissance and surveillance. In these missions, the noise produced by propeller-driven UAVs is a major drawback, which can be partially solved by installing an electric motor to drive the propeller. While the evolution of high performance brushless motors makes electric propulsion particularly appealing, at least for small and medium UAVs, all electric propulsion systems developed to date are penalized by the limited range and endurance that can be provided by a reasonably sized battery pack. In this paper we propose a hybrid propulsion system based on a recently developed ultramicro gas–turbine (UMGT), which can be used to power an electric generator, providing a significant range and (or) mission time extension. The UMGT is undergoing operational testing in our laboratory, to identify the most suitable configuration and to improve performance: a new compact regenerative combustion chamber was developed and several tests are being carried out to reduce its weight and size so as to increase, all other things being equal, the vehicle payload. This paper aims to propose a high endurance UAV, by a preliminary configuration selection and aerodynamic study of its performance.


2019 ◽  
Vol 304 ◽  
pp. 07004
Author(s):  
Spiridon Savvas ◽  
Pavlos Ramnalis ◽  
Alexandros Manoudis

The objective of this paper is to present the design of the Power Processing Unit (PPU) of the Microsatellite Electric Propulsion System (MEPS) program currently being developed at Elegant Bread Board (EBB). High efficiency, small size and weight and high reliability are the main parameters that special focus is given. The propulsion system of MEPS consists of two small size and low power (up to 300W) Thruster Units (TUs) each one composed of a Hall Effect Thruster and a Cathode, a single Propellant Management and Tank Assembly (PMA/PTA) and a single PPU. The PPU designed for the EBB phase has no redundancy, is fully flexible and capable of driving two different TU types (Rafael’s CAM-200 coupled with Rafael’s Heaterless Hollow Cathode (RHHC) and SITAEL’s HT100 coupled with SITAEL’s Heated Hollow Cathode (HC1)). This paper illustrates the core design requirements and important aspects on which the design was based. Preliminary results obtained from the coupling tests on the critical parts developed at Bread Board (BB), which contributed to the current design are also briefly depicted. Last but not least, the future development steps of the program that can become the driving factor for the successful implementation of an easily adjustable PPU compatible with a wide range of low power Electric Propulsion Systems (EPSs) are demonstrated.


Author(s):  
Oliver Rath

The MT30 has been developed specifically for 21st century marine propulsion and has now been applied in a wide range of different propulsion system configurations in the US Navy, the UK Royal Navy and the Republic of Korea Navy. Both naval and commercial marine propulsion systems are increasingly seeking more power from fewer prime movers to facilitate lower cost of ownership. In naval systems, the move to partial or full-electric propulsion for larger escorts and the introduction of single boost gas turbines for smaller escorts has allowed a reduction in the number of installed prime movers, while retaining and often enhancing survivability and redundancy. The Rolls-Royce MT30 marine gas turbine can be regarded as an enabling technology in this area to allow a wide variety of propulsion system options to be realised. This paper describes the current trends in Naval propulsion systems with particular focus on the platform design, operational and through-life benefits of the MT30 in the context of different system arrangements. A variety of different systems are covered with a particular focus on hybrid electromechanical and all-electric systems.


2020 ◽  
Vol 2020 ◽  
pp. 1-21
Author(s):  
Peng Zheng ◽  
Jianjun Wu ◽  
Yu Zhang ◽  
Biqi Wu

To develop the satellites for a low-Earth-orbit environment, atmosphere-breathing electric propulsion (ABEP) systems have become more attractive to researchers in the past decade. The system can use atmospheric molecules as the propellant to provide thrust compensation, which can extend the lifetime of spacecraft (S/C). This comprehensive review reviews the efforts of previous researchers to develop concepts for ABEP systems. Different kinds of space propulsion system are analysed to determine the suitable propulsion for atmosphere-breathing S/C. Further discussion about ABEP systems shows the characteristic of different thrusters. The main performance of the ABEP system of previous studies is summarized, which provides further research avenues in the future. Results show great potential for thrust compensation from atmospheric molecules. However, the current studies show various limitations and are difficult to apply to space. The development of ABEP needs to solve some problems, such as the intake efficiency, ionization power, and electrode corrosion.


Author(s):  
Roberto Capata ◽  
Luca Marino ◽  
Enrico Sciubba

In recent years, a renewed interest in the development of unmanned air vehicles (UAV’s) led to a wide range of interesting applications in the fields of reconnaissance and surveillance. In these types of mission, the noise produced by propeller driven UAVs is a major drawback, which can be partially solved by installing an electric motor to drive the propeller. The evolution of high performance brushless motors makes electric propulsion particularly appealing, at least for small and medium size UAVs. All electric propulsion systems developed to date are though characterized by the limited range/endurance that can be obtained with a reasonably sized battery pack. In this paper we propose a hybrid propulsion system based on recently developed, high efficiency micro-turbines which can be used to power an electric generator. The UMGT is under evaluation in our department, to achieve the optimal configuration and performances. For this scope a new compact regenerative combustion chamber has been developed and several tests has been carried out, with the aim to reduce weight and dimension and increase vehicle payload. In a high range/endurance mission the ultra-micro-turbine can provide the energy required for the cruise phase (the so-called “transfer to target”), while in the final approach, in which a quiet flight attitude is a demanding item, the battery pack drives the motor. The mission requirements adopted in the preliminary aircraft design presented here consist mainly of a long endurance (> 12 hours) step, with a cruise speed of 33.3 m/s and a dash speed of 45 m/s at an altitude of 5000 meters. The maximum take-off weight is 500 N, with a payload of 80 N. Under the above assumptions, a flying wing configuration for the UAV was defined, with a length of 1.6 meters and a span of 2.5 meters. A system of elevons assures the pitch and roll motion while a double vertical tail, in which a pusher propeller is lodged, guarantees the yaw stability and control.


Sign in / Sign up

Export Citation Format

Share Document