Micro-Propulsion System of a Thermospheric Explorer CubeSat

The major design driver for the Dipping Thermospheric Explorer (DipTE) CubeSat mission is that the satellite shall fly a significant amount of orbit arcs at altitudes of 300km and below. It is assumed that the DipTE satellite will be released in a circular orbit above the altitudes of scientific interest for the mission. A propulsion system will be employed to make the orbit elliptic and satisfy the design driver. The apogee of the elliptic orbit will be at the altitude of the initial circular orbit. The inclination of the orbit will stay the same. A few design iterations of the mission converged to a satellite configuration capable of storing 0.375 kg of propellant, and a propulsion system with a specific impulse Isp of 86 s. About 90 % of the total impulse of 313 Ns stored on board was budgeted to perform orbital maneuvers, with a 1 N thruster orbital maneuvering thruster (OMT). The remainder of 10% of the propellant mass has been budgeted for attitude control maneuvers, such as those performed during detumbling and initial attitude acquisition. The attitude control maneuvers are performed with the thrusters of a reaction control system (RCS). The 12 two-dimensional (2D) microthrusters of the RCS produce 40 mN each and are installed such that they provide three-axis control of the spacecraft. This paper describes the preliminary design of the propulsions system.

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Design and In-orbit Demonstration of REGULUS, an Iodine electric propulsion system

CEAS Space Journal ◽

10.1007/s12567-021-00374-4 ◽

2021 ◽

Author(s):

Nicolas Bellomo ◽

Mirko Magarotto ◽

Marco Manente ◽

Fabio Trezzolani ◽

Riccardo Mantellato ◽

...

Keyword(s):

Electric Propulsion ◽

Specific Impulse ◽

Input Power ◽

Propulsion System ◽

Electric Propulsion System ◽

Propulsive Performance ◽

Plasma Thruster ◽

Total Impulse ◽

Acceptance Tests

AbstractREGULUS is an Iodine-based electric propulsion system. It has been designed and manufactured at the Italian company Technology for Propulsion and Innovation SpA (T4i). REGULUS integrates the Magnetically Enhanced Plasma Thruster (MEPT) and its subsystems, namely electronics, fluidic, and thermo-structural in a volume of 1.5 U. The mass envelope is 2.5 kg, including propellant. REGULUS targets CubeSat platforms larger than 6 U and CubeSat carriers. A thrust T = 0.60 mN and a specific impulse Isp = 600 s are achieved with an input power of P = 50 W; the nominal total impulse is Itot = 3000 Ns. REGULUS has been integrated on-board of the UniSat-7 satellite and its In-orbit Demonstration (IoD) is currently ongoing. The principal topics addressed in this work are: (i) design of REGULUS, (ii) comparison of the propulsive performance obtained operating the MEPT with different propellants, namely Xenon and Iodine, (iii) qualification and acceptance tests, (iv) plume analysis, (v) the IoD.

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Microthruster Knife-Edge Thrust Stand

Volume 12: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2009-11854 ◽

2009 ◽

Author(s):

John Lee ◽

Adam Huang

Keyword(s):

Attitude Control ◽

Cost Effective ◽

Knife Edge ◽

Razor Blade ◽

Small Satellites ◽

Orbital Maneuvers ◽

Direct Technique ◽

Thrust Measurement ◽

Micro Propulsion ◽

Thrust Stand

Nano- and picosatellites are small satellites that are a more affordable alternative to larger satellites. Nanosats are satellites with a mass ranging from 1kg to 10kg while picosats have a mass that ranges from 0.1kg to 1kg. In addition to their cost, the smaller satellites have the advantage that they are able to carry out missions that would be difficult for a larger satellite. These advantages include using formations to gather data from multiple points and in-orbit inspection of larger satellites. Nano/picosats can be fabricated or procured for under $25k and launched into space for around another $40–60k which makes the total pre-mission expenditures for the satellite under $100k. Currently these satellites have a limited ability to orient themselves and cannot perform orbital maneuvers. For example a satellite could potentially use electro-magnetically charged coils in conjunction with earth’s magnetic field to orient themselves. The problems with the current methods of orientation are they are extremely slow in damping out oscillations due to low power and cannot execute out of orbit maneuvers. Thus, once a satellite is deployed from its launcher it is on a set orbit and cannot change its orbital elements on-command for the duration of its mission, limiting their use for science missions. Thus, it would be extremely beneficial for the nano- and pico-satellite community if a micro propulsion system capable of full-authority attitude control and orbital maneuver is developed. This paper describes the development of a cost-effective thrust stand for cold gas micro thruster development work. The thrust stand design is a static pendulum supported by a razor blade knife edge sitting on top of a silicon V-groove chip. The thrust measurement used is direct technique using a 1-axis strain gauge load cell at 25gm full-scale and resolutions in the order of 10 micro-g. Future possibilities include implementing a electromagnetic force compensation balance to improve sensing resolution.

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Characteristics of Two Phase Fluids as Microthruster Propellant

Volume 12: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2009-11853 ◽

2009 ◽

Author(s):

John Lee ◽

Adam Huang

Keyword(s):

Attitude Control ◽

Orbital Elements ◽

Two Phase ◽

Multiple Points ◽

Limited Ability ◽

Small Satellites ◽

Orbital Maneuvers ◽

Orbital Maneuver ◽

R 134A ◽

Micro Propulsion

Nano- and picosatellites are small satellites that are a more affordable alternative to larger satellites. Nanosats are satellites with a mass ranging from 1kg to 10kg while picosats have a mass that ranges from 0.1kg to 1kg. In addition to their cost, the smaller satellites have the advantage that they are able to carry out missions that would be difficult for a larger satellite. These advantages include using formations to gather data from multiple points and in-orbit inspection of larger satellites. Nano/picosats can be fabricated or procured for under $25k and launched into space for around another $40–60k which makes the total pre-mission expenditures for the satellite under $100k. Currently these satellites have a limited ability to orient themselves and cannot perform orbital maneuvers. For example a satellite could potentially use electro-magnetically charged coils in conjunction with earth’s magnetic field to orient themselves. The problems with the current methods of orientation are they are extremely slow to damp out oscillations due to low power (minutes) and cannot execute out of orbit maneuvers. Once a satellite is deployed from its launcher it is on a set orbit and cannot change its orbital elements on-command for the duration of its mission, limiting their use for science missions. Thus, it would be extremely beneficial for the nano- and pico-satellite community if a micro propulsion system capable of full-authority attitude control and orbital maneuver is developed. This paper describes the limiting characteristics of the refrigerant-based propellant (such as 1,1,1,2-Tetraflurorethan <R-134a> or 1,1-difluoroethane <R-152a>) for the cold gas systems that is currently under development.

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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Jet-HR1: Two-dimensional bipedal robot step over large obstacle based on a ducted-fan propulsion system

2017 IEEE-RAS 17th International Conference on Humanoid Robotics (Humanoids) ◽

10.1109/humanoids.2017.8246905 ◽

2017 ◽

Cited By ~ 2

Author(s):

Zhifeng Huang ◽

Biao Liu ◽

Jiapeng Wei ◽

Qingsheng Lin ◽

Jun Ota ◽

...

Keyword(s):

Propulsion System ◽

Two Dimensional ◽

Bipedal Robot ◽

Ducted Fan ◽

Step Over

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Desain Buku Ajar Matematika Bilingual Materi Bangun Datar Menggunakan Pendekatan PMRI Berkonteks Kebudayaan Lokal

Mosharafa: Jurnal Pendidikan Matematika ◽

10.31980/mosharafa.v7i3.134 ◽

2018 ◽

Vol 7 (3) ◽

pp. 345-356

Author(s):

Lisnani Lisnani ◽

Sheilla Noveta Asmaruddin

Keyword(s):

Retrospective Analysis ◽

Cultural Context ◽

Design Research ◽

Design Experiment ◽

Preliminary Design ◽

Two Dimensional ◽

Mathematics Textbook ◽

Concept Understanding ◽

Learning Mathematics ◽

Textbook Design

AbstrakPembelajaran matematika merupakan pembelajaran dari sesuatu yang bersifat konkret menuju abstrak. Hal ini sejalan dengan materi bangun datar yang cenderung abstrak. Namun, pada kenyataannya cara pemikiran siswa bersifat konkret. Maka dari itu, untuk menjembataninya diperlukan pendekatan yang mengutamakan pembelajaran yang bersifat konkret yaitu pendekatan PMRI (Pendidikan Matematika Realistik Indonesia). Pendekatan ini dilakukan dengan cara mendesain buku ajar bilingual berkonteks kebudayaan lokal melalui serangkaian aktivitas pembelajaran bangun datar menggunakan pendekatan PMRI. Penelitian ini merupakan penelitian design research yang terdiri dari tiga tahap yaitu preliminary design, the design experiment, dan retrospective analysis. Penelitian ini bertujuan menghasilkan lintasan belajar menggunakan buku ajar bilingual materi bangun datar. Pengumpulan data menggunakan lembar observasi, wawancara, dan lembar aktivitas siswa. Data dianalisis menggunakan lembar validasi dari ahli. Hasil analisis menunjukkan bahwa penggunaan buku ajar bilingual ini dapat meningkatkan pemahaman konsep siswa tentang bangun datar dari tahap informal ke tahap formal. Abstract (Bilingual Mathematics Textbook Design of Flat Building Topic Using Local Cultural Context PMRI Approach)Learning mathematics is a learning deriving from abstract towards concrete similarly to two-dimensional figure material. However, based on facts, the students’ thinking-process is concrete, which is abstract. Hence, to connect them, it is advisable to prioritize concrete learning. That is through Indonesia Realistic Mathematics Education (PMRI) approach by designing a bilingual Mathematics textbook based on local cultural context. This research is a design research consisting of three steps. There are preliminary design, the design experiment, and the retrospective analysis. The aim of the research produced a bilingual textbook in which the material focused on two-dimensional figure. Data collection by using observation sheet, interviews, and students’ worksheet. The data analysis by using validation sheet from the expert. The research is that the use of bilingual textbook using PMRI approach is able to improve the students’ concept understanding in two-dimensional figure from informal to formal step.

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Quasi-two-dimensional approximation for numerical simulation of flows in engine ducts

Progress in Propulsion Physics – Volume 11 ◽

10.1051/eucass/201911657 ◽

2019 ◽

Cited By ~ 1

Author(s):

V. Vlasenko ◽

A. Shiryaeva

Keyword(s):

High Speed ◽

Fuel Injection ◽

Three Dimensional ◽

Preliminary Design ◽

Two Dimensional ◽

Combustion Chambers ◽

New Approach ◽

One Dimensional ◽

Dimensional Approximation ◽

3D Flows

New quasi-two-dimensional (2.5D) approach to description of three-dimensional (3D) flows in ducts is proposed. It generalizes quasi-one-dimensional (quasi-1D, 1.5D) theories. Calculations are performed in the (x; y) plane, but variable width of duct in the z direction is taken into account. Derivation of 2.5D approximation equations is given. Tests for verification of 2.5D calculations are proposed. Parametrical 2.5D calculations of flow with hydrogen combustion in an elliptical combustor of a high-speed aircraft, investigated within HEXAFLY-INT international project, are described. Optimal scheme of fuel injection is found and explained. For one regime, 2.5D and 3D calculations are compared. The new approach is recommended for use during preliminary design of combustion chambers.

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