Title: Interplanetary CubeSat and Thin-Film Spacecraft/Lander/Rover systems for low cost fractionated missions
Michael Johnson, Imperial College London / PocketSpacecraft.com
Interplanetary CubeSats are a new class of spacecraft that aim to build on the success of the CubeSat format in low earth orbit (LEO), to potentially provide low cost access to space for interplanetary missions. PocketSpacecraft.com is an international project that has developed a low cost generic interplanetary CubeSat bus for the hosting and/or deployment of inexpensive instruments and probes for science missions.
The properties of the interplanetary CubeSat are defined parametrically by a traceability matrix driven configuration tool drawing on a library of standard components and subsystems that generates 0.5U (0.7kg) to 3U (5kg) CubeSat designs compliant with the CubeSat Design Specification and the requirements of launch systems. Outputs include a bill of materials specifying the standard and custom CubeSat subsystems (for example, communications, instruments, propulsion and power) to be purchased or manufactured to realise the design. Custom subsystems (for example, high power thin-film solar arrays, rad-hard compute modules and structures) are themselves parametrically defined, with the outputs of the CubeSat compiler feeding the inputs of the subsystem compilers. Documentation and protocols for the manufacture, assembly and operation of the CubeSat (for example, CAD drawings, communications plans and planetary protection documents) are also generated.
The compilers currently implemented have been designed to support fractionated LEO and lunar missions where the interplanetary CubeSat is designed to act as a deployer and communications relay for microprobes with masses ranging from less than 1g to 10g. These probes can be in the form of printed circuit board satellites (PCBSats– up to 32 x 32 x 4mm, $<$10g) or Thin-Film Spacecraft / Lander / >> Rovers (TF-SLRs – up to 80mm diameter x 50$\mu$m, $<$1g). Manufacture of TF-SLRs on orbit is an area of particular research interest.
These systems are designed for missions where large numbers of widely dispersed, relatively low fidelity measurements are helpful, and where individual elements may be unreliable or disposable, but the system as a whole reliable. Compatibility with existing space infrastructure and standards such as CCSDS communications systems and COSPAR planetary protection protocols has been considered from the outset. A technology demonstration mission is currently being prepared for launch, with the first science missions expected in the near future.