Synopsis
The report provides an overview of current technologies and development status for various small spacecraft subsystems, with a focus on components and systems that have achieved Technology Readiness Level (TRL) 5 or higher.
Power Systems
- Solar cells: Multi-junction III-V semiconductor solar cells with efficiencies over 32% are state-of-the-art. Triple junction cells offer a good efficiency/cost ratio.
- Solar panels: Rigid deployable and body mounted panels available. Specific power up to 165 W/kg. Peak power ranges from 2W (1U face) to 179W.
- Batteries: Lithium-ion and lithium polymer secondary batteries widely used. Energy densities up to 265 Wh/kg. Carbon-based anodes can provide fast charging and high cycle life.
- Power management: Modular electronic power systems with peak power tracking, battery charging, voltage regulation. Power ranges from 1-500W.
Propulsion
- Chemical thrusters with green propellants, microresistojet thrusters, pulsed plasma thrusters, and water electrolysis thrusters discussed.
- Electric propulsion options cover Hall effect thrusters, ion engines, pulsed inductive thrusters and more.
- Propellantless systems like electrodynamic tethers and solar sails also overviewed.
Guidance, Navigation and Control
- COTS star trackers, sun sensors, IMUs, magnetometers commonly used.
- Reaction/momentum wheels and control moment gyros from 0.04-45 Nms capability.
- Thrusters (chemical and electric) also used for attitude control.
Structures, Materials and Mechanisms
- Materials like aluminum, titanium, polymers, and composites used.
- Deployment mechanisms using shape memory alloys, Frangibolts.
- Structural performance from femto/picosats to ESPA-class smallsats covered.
Thermal Control
- Multi-layer insulation, optical coatings, heaters, heat pipes, loop heat pipes, thermal straps.
- Active systems use electrical heaters, thermoelectric coolers, and fluid loops.
Avionics
- On-board computers with processors from ARM Cortex-M0 to M7, PowerPC, LEON3-FT and RAD750.
- FPGAs from Xilinx, Microsemi and Intel (formerly Altera).
- Memory options include MRAM, FRAM, NAND/NOR flash, SD/microSD cards.
Communications
- S-band transmitters and transceivers available at all power levels and data rates.
- X-band becoming more popular for high data rate needs.
- Optical comm with data rates over 200 Mbps demonstrated on orbit.
The report covers additional subsystems like software, ground systems, launch and deployment, tracking, and deorbit systems. It provides a good overview of the current state of small spacecraft technologies.
