 | |
| Company type | Limited Company |
|---|---|
| Industry | Aerospace |
| Founded | 2000 |
| Headquarters | Stockholm , Sweden |
| Products | |
| Services | |
| Owner | Oak Universe |
| Website | https://www.ecaps.se/ |
ECAPS AB is a Swedish spacecraft propulsion company, established in 2000 as a joint venture between the Swedish Space Corporation (SSC) and Volvo Aero with the goal of developing and commercializing in-space thruster technology using a low toxicity Ammonium dinitramide (ADN) based liquid monopropellant called LMP-103S.
In 2006 ECAPS became a fully owned subsidiary of SSC. In June 2010 the PRISMA mission launched ECAPS' first flight 1N thrusters which were successfully operated until the decommissioning of PRISMA in 2015. In July 2023, ECAPS was acquired by Oak Universe. [1]
ECAPS technology (thrusters + propellant) has successfully flown on the following missions:
| Name | Organization | Launch Date | Organization Type |
|---|---|---|---|
| PRISMA | SSC | June 2010 | Government |
| SkySat-3 | Skybox Imaging | June 2016 | Commercial |
| SkySat-4, 5, 6, 7 | Skybox Imaging | Sept 2016 | Commercial |
| SkySat-8, 9, 10, 11, 12, 13 | Planet | Oct 2017 | Commercial |
| SkySat-14, 15 | Planet | Dec 2018 | Commercial |
| STPSat-5 | Sierra Nevada Corp | Dec 2018 | Government |
| SkySat-16, 17, 18 | Planet | June 2020 | Commercial |
| SkySat-19, 20, 21 | Planet | upcoming | Commercial |
| GEOSat-1 | Astranis | upcoming | Commercial |
| ArgoMoon | Argotec | upcoming | Government |
| ELSA-d | Astroscale | Feb 2024 | Commercial |
| SL-OMV | Moog | upcoming | Commercial |
The ECAPS thruster technology produces thrust by thermally and catalytically decomposing, igniting, combusting, and exhausting monopropellant LMP-103S fed into the thruster's reactor. LMP-103S is a 'green' high performance storable liquid propellant based on ammonium dinitramide (ADN) blended with fuel, stabilizer and solvent. The thruster is composed of:
A series redundant, normally closed, solenoid valve with PTFE seat material.
Composed of the FCV interface including two (redundant seal) EPDM O-rings, the feed tube, the feed tube heat-sink, and the injector head.
Structural member between the FCV and the main thruster elements, which serves as a heat barrier. It is sized to suppress severe heat soak back from the thruster to the FCV.
Houses the staged reactor, which houses the propellant catalyst. The thrust chamber upstream side is brazed to the injector head. The nozzle is an integrated part of the thrust chamber on the down-stream side and is conical with an exit-to-throat area ratio of 100:1. The thrust chamber is made of iridium lined rhenium to withstand the high temperature reaction products of propellant combustion and the resulting thermal cycling.
Reactor heater is embedded in an Inconel tube with a ceramic insulator. The heater is a coiled tube which is integrated into heater carrier, which in turn is integrated via thermally conductive parts into the injector head.
Type K (chromel/alumel) and is embedded in an Inconel tube with a magnesium oxide insulator. The thermocouple is used for monitoring and controlling the pre-heating temperature.
Development of the storable liquid propellant blend LMP-103S began in 1997 between the Swedish Space Corporation and the Swedish Defense Research Agency. The top design priorities were to improve performance and reduce handling hazards as compared to hydrazine. Long term ground storage testing of the LMP-103S propellant in a flight-like system began in October 2005 and has demonstrated no measurable degradation or pressure build-up. Transport is approved as an UN/DOT1.4S article. Air transport on commercial flights of the LMP-103S propellant has been performed to the United States, the United Kingdom, Japan, Switzerland, Russia, India French Guiana, and within Sweden.
The propellant is 63.0% ADN, 14.0% water, 18.4% methanol and 4.6% ammonia by weight. LMP-103S has different properties than other traditional propellants such as hydrazine and nitrogen tetroxide. The latter are pure liquids, which (except for trace contaminants) can be completely evaporated, leaving no residues. In contrast, LMP-103S is a mixture comprising a high concentration of ADN "salt" dissolved in a mixture of solvents. Evaporation leads to a loss of solvents and thereby a changed composition of the solution (the ADN salt has no vapor pressure, so it only exists in solid or dissolved form). The solution does not have a distinct freezing point, but rather a temperature when the solution becomes saturated and solid ADN crystals will start to form in the liquid solvents (this is, however, a reversible phase separation).
A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants (fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder; The inception of gunpowder rockets in warfare can be credited to the ancient Chinese, and in the 13th century, the Mongols played a pivotal role in facilitating their westward adoption.
A monopropellant rocket is a rocket that uses a single chemical as its propellant. Monopropellant rockets are commonly used as small attitude and trajectory control rockets in satellites, rocket upper stages, manned spacecraft, and spaceplanes.
A resistojet is a method of spacecraft propulsion that provides thrust by heating a typically non-reactive fluid. Heating is usually achieved by sending electricity through a resistor consisting of a hot incandescent filament, with the expanded gas expelled through a conventional nozzle.
An arcjet rocket or arcjet thruster is a form of electrically powered spacecraft propulsion, in which an electrical discharge (arc) is created in a flow of propellant. This imparts additional energy to the propellant, so that one can extract more work out of each kilogram of propellant, at the expense of increased power consumption and (usually) higher cost. Also, the thrust levels available from typically used arcjet engines are very low compared with chemical engines.
Monopropellants are propellants consisting of chemicals that release energy through exothermic chemical decomposition. The molecular bond energy of the monopropellant is released usually through use of a catalyst. This can be contrasted with bipropellants that release energy through the chemical reaction between an oxidizer and a fuel. While stable under defined storage conditions, monopropellants decompose very rapidly under certain other conditions to produce a large volume of its own energetic (hot) gases for the performance of mechanical work. Although solid deflagrants such as nitrocellulose, the most commonly used propellant in firearms, could be thought of as monopropellants, the term is usually reserved for liquids in engineering literature.
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A propellant is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine. Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two distinct concepts.
A solar thermal rocket is a theoretical spacecraft propulsion system that would make use of solar power to directly heat reaction mass, and therefore would not require an electrical generator, like most other forms of solar-powered propulsion do. The rocket would only have to carry the means of capturing solar energy, such as concentrators and mirrors. The heated propellant would be fed through a conventional rocket nozzle to produce thrust. Its engine thrust would be directly related to the surface area of the solar collector and to the local intensity of the solar radiation.
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