This topic covers all relevant families of composite materials for space applications, including fibre-reinforced thermoset (such as epoxy and cyanate ester) and thermoplastic (such as PEEK) composites, carbon-carbon composites, ceramic matrix composites, and metal matrix composites. The content of the topic is classified as listed below.

• Polymer Matrix Composites (PMCs): polymer-based resin (thermoset or thermoplastic) matrices reinforced with a variety of fibres (glass, carbon, aramid). These are the most widely used composite materials for space applications.
• Metal-Matrix Composites (MMCs): metal (e.g. aluminium, magnesium, titanium, copper, silver) matrices reinforced with fibres or particles that can resist the manufacturing process (e.g. silicon carbide or high melting-point metal).
• Ceramic Matrix Composites (CMCs): carbon (or graphite) matrices reinforced with carbon (or graphite) fibres. Mainly used in very demanding applications (high temperature environments, high stability).

For each of the categories above, various materials as well as manufacturing processes are discussed.

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This topic is focused on Gallium Nitride (GaN) and Silicon (Si) technologies for active RF devices employed in RF blocks such as amplifiers, frequency converters and modulators. The role of GaN is fostered in RF power amplification up to the 100-GHz range, whereas Si technologies, in particular RF CMOS and BiCMOS, are increasingly substituting traditional GaAs for RF circuits in certain low-power functions such as routing, conditioning, signal generation and frequency synthesis up to Ka-band.

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Cryogenics in general is the domain of thermal science dedicated to the study and the production of temperature below 200K (according to ECSS-E-ST-31C definition). Applied to the Space Sector, this term describes the different types of technologies that permit to reach and maintain such temperatures. The following technologies are covered: 

- Radiators 

- Thermoelectric coolers 

- Cryostats 

 -Active cooling systems from 2K to 190K

• Stirling cooler 
• Pulse Tube cooler 
• Joule Thomson expansion cooler 
• Solid Sate cooling (e.g. laser-coolers) 
• Reverse Turbo-Brayton cooler 
• Microcooling 

- Sub-Kelvin cooler:

• Adiabatic Demagnetisation Refrigerators (ADR) 
• Dilution Refrigerator 
• 3He-sorption pump cooler 

- Cooler drive electronics 

- Cryogenic System Equipment: equipment required to integrate the above mentioned cooling systems with the detectors and the Spacecraft 

- Cryogenic technologies for space transportation

• Cryogenic insulation solutions 
• Propellant management
• Cold/Liquid Gas storage and transfer

- Cryogenics Heat Pipe and Loop Heat Pipes (for this one see the topic Heat Transport Equipment and Systems)

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This topic addresses chemical, electric and advanced propulsion systems suitable for CubeSats of sizes up to 16U or 30kg of mass and capable of delivering thrust up to 0.5N. It covers:

• Chemical propulsion thrusters
• Cold Gas
• Mono-propellant
• Bi-propellant 
• Solid propellant
• Hybrid propellant
• Water electrolysis
• Electrostatic: Atmospheric Breathing Electric Thruster (ABEP), Electron Cyclotron Resonance (ECR) thrusters, Electrospray thrusters, Field Emission Electric Propulsion (FEEPs), Gridded on Ion Engines (GIEs), Hall Effect Thrusters (HTs), High Efficiency MagnetoPlasmaDynamic Thrusters (HEMPTs)
• Electrothermal: Resistojet, Microwave Electrothermal Thrusters, Arcjets
• Electromagnetic: Pulsed Plasma Thrusters (PPTs), Vacuum Arc Thrusters (VATs), Helicon Plasma Thrusters including Ambipolar Thrusters, Electron Cyclotron Resonance Thrusters
•  Other components: power and control electronics, power processing units, tanks, manifolds, feed systems, thruster pointing mechanisms, propulsion system modelling, test facilities, test diagnostics including thrust balances, propellants, GSE, pressure regulators, pressure transducers, mass flow sensors, mass flow controllers, temperature sensors, valves, filters, cathodes/neutralisers, harness and pipework.

Note that the coverage differs from that of Chemical Propulsion – Components (including Tanks) and Electric Propulsion Technologies principally in size, delivered thrust levels and approach adopted to qualification.

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To limit the growth of space debris in an increasingly crowded space environment, new de-orbiting technologies and tools are required. These include technologies to passivate and dispose of the space segment, tools to model the reliability and compliance of such techniques, and solutions to ease the removal from orbit of spacecraft in case of failure. This topic covers technologies related to the areas listed below.

- De-orbit systems

• Passive de-orbit systems (e.g. drag augmentation devices, tethers)
• Active-de-orbit systems (controlled re-entry and semi-controlled re-entry)
• Autonomous de-orbit systems

- Passivation (power, propulsion)

- Reliability of disposal systems for de-orbiting and passivation

- Design for Demise (e.g. tanks, reaction wheels, magnetometers, early break-up and containment technologies)

- Design for Removal (mechanical capture interface, detumbling technologies, markers, retroreflectors)

- System-level integration and validation

Note that this topic is closely related with ESA’s Zero Debris approach and ESA’s Clean Space office activities.

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Deployable boom technology (consisting of booms and masts) is typically associated with deployable, elongated structural members, where the cross section is by far smaller than the deployed length. These kinds of structures are stowed for launch and then deployed to their operational configuration. This topic covers all various technologies of the booms and masts., including multiple degree of freedom articulated long booms. Inflatable structure technology covers support/deployment structures for satellite appendages (beams, tori, reflectors, etc.), inflatable reflectors/antennas and inflatable re-entry bodies, habitats, airbags and balloons.

- Deployable booms

• Structural members
• Joints
• Synchronisation mechanisms

- Inflatable structures

• Inflatable element
• Inflation system
• Rigidisation system
• Launch containers

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Electric Propulsion uses electricity to accelerate a propellant and produce thrust. This topic covers the technologies for use in space listed below.

- EP thrusters

• Electrostatic: Electrospray Thrusters, Field Emission Electric Propulsion, Grided Ion Engines, Hall Effect Thrusters, High Efficiency Multistage Plasma Thrusters, Quad Confinement Thrusters
• Electrothermal: Arcjets, Resistojets, Microwave Electrothermal Thrusters 
• Electromagnetic: Pulsed Plasma Thrusters, Vacuum Arc Thrusters, Magneto Plasma Dynamic Thrusters, Helicon Plasma Thrusters, Electron Cyclotron Resonance Thrusters

- Cathodes/Neutralisers

- Power Processing Units

- Flow Control Units

- Radio Frequency Generators

- Filters and valves

- Pressure regulators 

- Pressure and temperature sensors

- Electric Propulsion Pointing Mechanisms

- Test facilities, Diagnostic Probes and Ground Support Equipment

- Thrust Balances

- Models and Codes

Note that Tanks are covered in Chemical Propulsion – Components (Tanks).

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Energy Storage is a key part of almost every space mission, and is used to supply power during eclipse, to manage peak loads, and as a one-off (or contingency) source of electrical power.

Electrochemical energy storage is a subset of energy storage and it refers to technologies that store energy chemically to produce electrical power. 

• Batteries: including primary batteries (non-rechargeable and thermal) and secondary, batteries (rechargeable)
• Regenerative fuel cell systems: including H2/O2 fuel cells and electrolysers, solid oxide fuel cell, and Co/CO2 fuel cells
• Supercapacitors: including Li ion capacitor

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Electromagnetic Compatibility (EMC) ensures that electrical equipment operates correctly in its environment without causing or experiencing interference. This is crucial for spacecraft, as EMC issues can lead to reduced performance or mission failure. EMC is not a technology as such, but in the context of harmonisation the EMC design, modelling and simulation tools, and test techniques are considered as technology.

-Design, modelling and simulation

• Design for electromagnetic cleanliness and compatibility
• Electrical harness design and technology,including connectors and cable assembiles
• Electromagnetic environment
• Developement of EMC models and simulation tools

- Test techniques 

• EMC test and measurement techniques 
• Magnetic test methods, magnetic modelling and simulation 
• Non-standard test methods for highly demanding requirements (approach for large infrastructure, e.g. habitat modules)

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Fluid mechanics is the discipline that studies the flow of fluids: liquids and gases. Space applications are related to ascent, descent, landing, aerobraking, aerocapture, and aerogravity assist.

The Dossier covers the following 5 main aresas

- Developing and Improving Fluid Mechanics Hardware

• Innovative aerodynamic surfaces (primary and complementary)
•  Filling and refilling technologies for cryogenic and storable propellants to enable reusable propulsion system operating on ground and in-flight
• Fluid mechanics hardware and equipment for the management of liquids and gases including decelerators and advanced technologies for management of sounds and acoustics of space vehicles and innovative intake air collectors for air-breathing propulsion systems.

- Developing and Improving Fluid Mechanics Tools and Techniques

• Classical Computational Fluid Dynamics (CFD) tools: Euler, Navier-Stokes and direct simulation Monte Carlo codes and associated grid generation tools
• Advanced numerical methods: Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS) for high-fidelity simulation of smaller-scale turbulent structures
• Physical models including thermochemistry, turbulence, transition, radiation, gas-surface interactions (oxidation, catalysis, ablation) and combustion
• Design tools: analytical, fast parametric design tools, optionally coupled with trajectory analysis tools. Aerodynamic (ATD) database generation
• Multi-disciplinary tools: informatic environment for coupling tools and databases of different technical disciplines; optimisation algorithms
• Plume impingement: interaction between thruster plume and spacecraft or ground surfaces

- Developing New Capabilities and Maintaining Ground Testing Facilities

• Ideal Gas Facilities: classical subsonic, transonic, supersonic, and hypersonic wind tunnels and corresponding intrusive and nonintrusive measurements techniques
• High Enthalpy Facilities: shock tubes, hot-shot wind tunnels, ballistic ranges
• Plasma Facilities: arcjets and plasmatrons
• Rocket Nozzle Test Stands: hot firings and jet interaction
• Decelerator facilities
• High Performance Computing (HPC) Systems

- Developing and Enhancing Sensors and Measurements Techniques

• In-flight measurements (intrusive and non-intrusive) such as Air Data Systems, intelligent measurement systems, and miniaturisation of flight measurement techniques.

- Developing Flight Demonstrators and Flight Data Analysis Tools

• Flight and ground demonstration missions and experimental vehicles to study critical phenomena in ATD; exploitation of data from flight experiments, specially involving ATD and (re-)entry.

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