Alexander Reissner’s scientific contributions


Ad

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (18)


Figure 1. ENPULSION FEEP propulsions systems that have achieved space heritage from left to right: heritage NANO, NANO R 3 , NANO AR 3 and MICRO R 3 .
Figure 4. Impedance evolution over time for NANO heritage thruster used in LEO as a function of days since thruster commissioning. At time of extractor cleaning, the total accumulated firing duration amounted to approximately 1350 hours. The plot identifies different operational ranges (operational parameters and duration). The data shows the characteristic decrease of impedance due to extractor shrinkage beyond day 220. After performing the extractor cleaning procedure, an initial increase of the impedance followed by rapidly decreasing impedance similar to the behavior seen in initial commissioning and consistent with the again increased extractor diameter is noticeable.
Fig 5 shows previously reported low resolution telemetry of one of the NANO AR 3 .
Figure 5. Telemetry of a NANO AR 3 system used in GEO: thrust, total system power including neutralization and propellant heating and ion emission current 17 (left) and emission voltage and current, as well as extractor segment voltages used to control thrust vector 17 (right)
Flight heritage of Indium-based FEEP propulsion systems across different applications and orbits: In space cleaning of extractor electrode
  • Conference Paper
  • Full-text available

June 2024

·

46 Reads

·

Federico Toller

·

Tony Schönherr

·

[...]

·

Since the first flight of a Field emission electric propulsion (FEEP) thruster in 2018, more than 200 FEEP based propulsion systems have been launched, including 190 heritage ENPULSION NANO systems, 18 higher power MICRO systems and 9 novel NANO R 3 /AR 3. The latter are the successor products of the heritage NANO, with the AR 3 version allowing for direct thrust vectoring capability without moving parts. All propulsion systems reported in this work are based on passively fed, Indium based liquid metal FEEP technology. This work reports the latest launch and flight heritage statistics. We present telemetry of different propulsion systems used in different applications and orbits, and present the successful on orbit extractor cleaning procedure conducted after 1350 hours of accumulated firing on a heritage NANO thruster in LEO. Nomenclature FEEP = Field emission electric propulsion GEO = Geostationary orbit IOD = In orbit demonstration LEO = Low earth orbit 1 Chief Science Officer, ENPULSION, david.krejci@enpulsion.com.

Download


Figure 2 Plot of required and achieved thrust of HiPARC over mission time of transfer to Mars. In addition, the corresponding thruster quantity is shown in blue line
Figure 6 Plot of propellant consumption per trajectory section, which is necessary to generate the required thrust, over mission time of transfer Earth to Mars showing relevant thruster types. Breaks show that required thrust is not achieved with this thruster and therefore another thruster has to be used during this trajectory section
Figure 8 CAD design of gridded cluster plate including European/DEMOCRITOS electric thrusters with redundant PPUs for each thruster at the backside. Thruster colours show the colour of the plume, due to the preferred propulsion material
Figure 9 Percentages of trajectory sections for the cluster of European and DEMOCRITOS thruster
Figure 10 Percentages of trajectory sections for the cluster of Japanese and DEMOCRITOS thrusters
Cluster of electric thrusters for astronautic and robotic INPPS flagship space flights to Mars and Europa moon

April 2023

·

446 Reads

·

3 Citations

EPJ Techniques and Instrumentation

This review deals with the selection of the electric propulsion system (EPS) for the internationally developed and designed, primary nuclear-electric space tug International Nuclear Power and Propulsion System (INPPS). INPPS is scheduled for interplanetary missions to Mars and Jupiter moon Europa missions by the end of decade 2020. Regarding specific technical and mission parameters preselected electric thruster (ET) types, developed by international companies and institutions, are analysed, evaluated and investigated for a possible application as propulsion system (PS), the so-called CET (Cluster of Electric Thrusters). It is analysed whether solely electric thrusters, combined in an adequate CET, enable the envisaged interplanetary missions—robotic and astronautic/crewed with the INPPS flagship. Thruster clusters with strategic consortium considerations are analysed as a feasible PS of the INPPS. The studied CET consists of the following: (a) only European ETs, (b) combination of German and European ETs, (c) Japanese and European ETs or at least (d) Japanese, European and US thrusters. The main results are (1) Robotic and crewed INPPS mission to Mars/Europa are realizable with EPS only (no chemical propulsion is needed), (2) that every CET, except (c) of only Japanese and part of European thrusters, is capable to perform the main part of envisaged INPPS flagship mission orbit to Mars, back to Earth and to Jupiter/Europa moon.


Fig. 1 Heritage system with significant flight heritage: NANO propulsion system
Fig. 2 Next generation R 3 propulsion systems in space to date: MICRO R 3 (left) and NANO AR 3 (right)
Fig. 3 NANO, NANO R 3 and MICRO R 3 direct thrust measurements, facilities and original publication indicated if applicable. NANO (thrust measurement at ESA facility) [29]. NANO R 3 (thrust measurement at FOTEC facility) [30]. MICRO R 3 (thrust measurement at FOTEC facility)
Fig. 8 NANO R 3 (left) and NANO AR 3 (right) propulsion systems
Summary of ENPULSION propulsion systems in space
Large number system integration aspects: on orbit data and lessons learnt from launching 144 FEEP propulsion systems

December 2022

·

262 Reads

·

4 Citations

Journal of Electric Propulsion

This manuscript discusses the on orbit data availability and system integration aspects of the ENPULSION NANO liquid metal FEEP propulsion systems. We present flight data from thrusters on LEO spacecraft, and present and discuss data availability from 142 NANO propulsion systems that were launched in the previous 4 years on 64 different spacecraft, ranging from 3 U Cubesats to > 100 kg platforms. In parallel, new propulsion systems based on FEEP technology have been developed, expanding the thrust and power range and introducing new features, as well as lessons learnt from the large space heritage of the NANO. Two of these new propulsion systems have been launched to space so far. In this work we present telemetry of NANO operation over several hundred hours as well as aggregated on orbit statistical data of the NANO including the thrusting time over all units in space which accumulated to > 3000 h of thrusting. We then discuss challenges encountered and present lessons learnt during on orbit operations, customer AIT support and ground test campaigns conducted at different facilities.


The first 100 FEEP propulsion systems in space: A statistical view and lessons learnt of 4 years of ENPULSION

June 2022

·

1,466 Reads

·

5 Citations

The in-orbit demonstration of an ENPULSION NANO propulsion system in 2018 marked the first liquid metal field emission electric propulsion system tested in space, and the successful introduction of the ENPULSION NANO. In the four years since then, this propulsion system was successfully industrialized and 136 systems have flown on 61 different spacecraft. In parallel, new propulsion systems based on FEEP technology have been developed, expanding the thrust and power range and introducing new features and lessons learnt from the large space heritage of the ENPULSION NANO. Two of these new propulsion systems have been launched to space so far. This paper present telemetry data of ENPULSION NANOs from several spacecraft, including larger orbital change maneuvers, and discusses applications utilizing ENPULSION NANO systems so far. We then provide an overview of the current onorbit statistics of the ENPULSION propulsion systems. We present aggregated onorbit statistical data of the ENPULSION NANO, discuss challenges encountered and present lessons learnt during onorbit operations, customer AIT support and ground test campaigns conducted at different facilities.


SPACE PROPULSION 2022 Testing the NANO AR³ FEEP cubesat electric propulsion system at ESA Propulsion Laboratory

June 2022

·

524 Reads

·

2 Citations

Space propulsion systems undergo thorough ground testing before being deployed in space. We report the results of a functional verification and performance characterisation test campaign of an integrated electric propulsion system for cubesats and microsats with purely electric thrust vectoring capability and no moving parts. Visualisations of the plume data obtained from Faraday cup scans show a clear, corresponding trend of the variation of the inclination and azimuth angles of the thrust vector when these are commanded. The divergence angle computed from plasma diagnostic data is 49°, independently of the achieved inclination of the ion beam.


ENPULSION NANO and MICRO propulsion systems: development and testing

August 2021

·

100 Reads

·

7 Citations

View Video Presentation: https://doi.org/10.2514/6.2021-3420.vid The ENPULSION NANO and the ENPULSION MICRO are both based on liquid metal Field Emission Electric Propulsion (FEEP) principle, producing thrust by electrostatically accelerating previously extracted and ionized propellant to high exhaust velocity. The Indium FEEP emitter is based on passive propellant supply from the integrated propellant reservoir via capillary forces to the porous metal ion emitter featuring 28 needle-shaped porous emitters, arranged in a crown-like geometry. The NANO thruster features one such emitter, whereas the MICRO features 4 emitter crowns operated in parallel to increase thrust. Electrostatic pull between the liquified Indium and the counter electrode surrounding the emitter crown establishes a so-called Taylor cone on the tips of the needle emitters, from who’s apex the ion emission takes place. This principle is based on long heritage of Liquid metal ion sources (LMIS) and sources for mass spectroscopy used for spaceflight, and has gained significant interest as propulsion system for commercial smallsat missions. This work provides an overview of disclosable in-flight experience and reports on testing characterization progress of both propulsion systems.


Humans to Mars: by MARS- plus EUROPA-INPPS Flagship Mission

June 2021

·

82 Reads

The first non-human INPPS (International Nuclear Power and Propulsion System) flagship flight with orbits Earth-Mars-Earth-Jupiter/Europa (after 2025) is the most maximal space qualification test of INPPS flagship to carry out the second INPPS flagship flight to Mars with humans (in the 2030th). This high power space transportation tug is realistic because of A) the successful finalization of the European-Russian DEMOCRITOS and MEGAHIT projects with their three concepts of space, ground and nuclear demonstrators for INPPS realization (reached in 2017), B) the successful ground based test of the Russian nuclear reactor with 1MWel plus important heat dissipation solution via droplet radiators (confirmed in 2018), C) the space qualification of the Russian reactor by 2025 and D) the perfect celestial constellation for a Earth-Mars/Phobos-Earth-Jupiter/Europa trajectory between 2026 and 2035. Therefore the talk sketches the preparation status of INPPS flagship with its subsystems. Critical performance will be studied by parallel realizations of the ground and nuclear demonstrators of DEMOCRITOS (until 2025). The space qualification of INPPS with all subsystems including the nuclear reactor in the middle of the 2020th plus the INPPS tests for about one to two years - first in high Earth orbit robotic assembly phase of INPPS and later extended in nearby Earth space environment flight - means a complete concepts driven approval for all applied INPPS space subsystem technologies. It is also important to consider wider aspects for the overall mission implementation phase. Component like the nuclear reactor as the power source for the propulsion system will have to agree with the 1992 UN principles relevant to the use of nuclear power sources (NPS) in outer space. Therefore this talk will look into the legal and policy issues of nuclear space systems related to the international realization of mission design, requirements of associated safety regulations (including AI applications in the subsystems) and new aspects for INPPS flagship commercialization and new media communication on board.



Figure 2. IFM Nano Thruster (left), IFM crown emitter during ion emission (right, from Ref. 10)
Figure 9. IFM06.02 Thruster telemetry during multiple consecutive firings
Figure 14. IFM06.04: System power consumption and emitter power draw for 350!N operation point
Recent flight data from IFM Nano Thrusters in a low earth orbit

October 2019

·

1,418 Reads

·

15 Citations

The IFM Nano Thruster is a high specific impulse liquid metal Field Emission Electric Propulsion (FEEP) system that has been flown on multiple space missions ranging from 3U Cubesats to 100 kg class satellites. The core component of the thruster is a crown-shaped porous metal ion emitter featuring 28 ion emission sites, with propellant supplied passively by capillary forces, obviating the need for pressurized tanks. The metal propellant used is solid during integration and launch, and is only liquefied in orbit, thus significantly simplifying handling and integration. The thruster itself is a fully contained package of less than 1U including power electronics, with applications ranging from orbit control, formation flight control, attitude control to orbit raising and deorbiting. This paper presents the testing, integration and flight data of multiple IFM Nano Thrusters integrated in a Small Satellite. The paper presents the telemetry data acquired during the commissioning phase of 4 thrusters.


Ad

Citations (15)


... Based on this technology, the Austrian spin-out company ENPULSION further developed and commercialized the IFM NANO product series in 2018 for the first time. By the end of 2023, more than 185 FEEP products had been launched into space on 79 different spacecraft worldwide [9]. Meanwhile, working for ARC in the early years of the 21st century, Tajmar conducted significant fundamental research on FEEP technology, developing and proposing several theoretical methods based on experimental measurements [10][11][12]. ...

Reference:

Study on the Improvement of Theoretical and Electric Field Simulation Methods for the Accurate Prediction of FEEP Thruster Performance
Informing FEEP thruster design utilizing the flight heritage from 167 thrusters in LEO and GEO
  • Citing Conference Paper
  • January 2024

... A more complex heterogenous cluster may lead to significant ∆ savings for a specific mission. This possibility has been shown in Ref. 17, in which a heterogenous cluster of electric thrusters has led to significant savings in ∆ requirements for a transfer to Mars and back with a NEP spacecraft compared to the usual values, e.g. given here in Subsection A. Nevertheless, a homogenous thruster cluster has been assessed in this work to obtain a first broad analysis result with possibility for further optimization. ...

Cluster of electric thrusters for astronautic and robotic INPPS flagship space flights to Mars and Europa moon

EPJ Techniques and Instrumentation

... The limited visibility on flight data, as well as biases introduced by the fact that access to telemetry is often coinciding with specific mission stages such as commissioning, while less visibility is generally possible during regular operations, has been discussed previously 15,19 . In an effort to gain visibility on historical telemetry in 2022/2023, a significant increase in the available historical flight data could be achieved for the timeframe up to 2022, increasing the flight telemetry available for this period by almost a factor of 3 compared to previously presented data availability, and confirming previous assumptions on data visibility leading to an underestimation of the actually achieved hours of operations on orbit. ...

Large number system integration aspects: on orbit data and lessons learnt from launching 144 FEEP propulsion systems

Journal of Electric Propulsion

... The limited visibility on flight data, as well as biases introduced by the fact that access to telemetry is often coinciding with specific mission stages such as commissioning, while less visibility is generally possible during regular operations, has been discussed previously 15,19 . In an effort to gain visibility on historical telemetry in 2022/2023, a significant increase in the available historical flight data could be achieved for the timeframe up to 2022, increasing the flight telemetry available for this period by almost a factor of 3 compared to previously presented data availability, and confirming previous assumptions on data visibility leading to an underestimation of the actually achieved hours of operations on orbit. ...

The first 100 FEEP propulsion systems in space: A statistical view and lessons learnt of 4 years of ENPULSION

... This method for thrust steering has been patented in 2019 [37]. A model of the ENPULSION AR³ [38] incorporating this technology was tested at the ESA Propulsion Laboratory, where the inclination of the ion beam was measured by means of Faraday cups for several thrust vector setpoints [39]. ...

SPACE PROPULSION 2022 Testing the NANO AR³ FEEP cubesat electric propulsion system at ESA Propulsion Laboratory

... A recent keen interest in novel electric propulsion technologies stems from an increasing number of small satellites being deployed for plural applications [1][2][3][4][5]. Simple and compact thrusters might enable in-space maneuvering of such small spacecrafts [6]. ...

ENPULSION NANO and MICRO propulsion systems: development and testing
  • Citing Conference Paper
  • August 2021

... If only the anode current is considered as the current available for the neutralization, considering the losses to the electrodes, the BBM-DN3.4 results having a power to current ratio of 0.25 W/mA, which compares favourably with the values found in available literature [6]. The FEEP NU is able to emit 6 -10 mA with a power consumption of 0.5 -0.9 W/mA, since half of cathode current is collected by the gate [21,22], while the IFM Nano Thruster adopts a dry neutralizer at 0.5 W/mA with a total emission of 5 mA [23]. Figure 9 shows the currents as a function of the gate bias at various anode voltages. ...

Recent flight data from IFM Nano Thrusters in a low earth orbit

... They attribute these changes in total yield to the formation of an oxide layer on the surface. However, other studies have found that ion etching for long periods of time produces several [79][80][81][82] Other studies, such as that by Hugonnaud et al., 83 obtained their emission results from the interaction between the plume of an electric thruster 84,85 and the testing facility walls, as an average over 800 data samples acquired over 25 min under much lower ion beam currents and irradiation doses than. Hasselkamp et al. 73 This proves that a link exists between the nature of the irradiation source and the microstructural evolution of the material being bombarded, especially close to the surface, resulting in different emission yields. ...

Development, Production, and Testing of the IFM Nano FEEP Thruster

... If deployable radiator panels are used, it is very important to ensure that the thermal conductivity is higher for the hinges used. Flexible thermal straps along with proper mechanical hinges, which have variable bending angles, can be used to deploy radiators [33]. Flexible thermal straps can be considered for thermal connection between the heat dissipating element and the deployable radiator. ...

Thermal Control of High Power Applications on CubeSats

... Therefore, this configuration is used for ASPOC-NG. The IFM Nano Thruster consists of a porous tungsten crown and is proven in-orbit operation Seifert et al., 2018;Jelem et al., 2018). Furthermore, a lifetime test of such a porous crown emitter has hit the 42 000 h mark and is still ongoing. ...

Direct Thrust and Plume Divergence Measurements of the IFM Nano Thruster
  • Citing Article
  • June 2018

Advances in Space Research