The micro satellite platform S2TEP will allow DLR to independently carry out technology experiments in the space environment. The satellite bus is built using modular and scalable technologies developed within DLR; this guarantees a fast and cost-effective implementation, as well as the ability to adapt the bus to various user requirements.
Satellites have a great impact on our daily life, enabling for instance global communications and navigation services or weather forecasts. The space research conducted by DLR has made, and continues to make, important contributions within this sector, enabling the digitalization and mobility of the future.
In order to promote space flight research, as well as supporting new innovative technologies, DLR has defined a strategy for its future involvement in space research and technology development. The strategy foresees the development of two satellite platforms; one in the size of 20-50kg (S2TEP), flown every 2-3 years; and one in the size of 200kg (COMPSAT), flown every 5-6 years. These two continuously ongoing projects will make significant contributions to the scientific progress of DLR by:
The idea behind S2TEP
The subsystems of a satellite are often mission specific developments; this limits the ability for reuse in other missions, and makes adaptations to new requirements difficult. To streamline this process, DLR is developing its own satellite platform, designing main avionic components that are easily adaptable; and at the same time utilizes the latest research and technology.
The platform also offers a higher degree of flexibility; enabling short-term design adjustment; as well as the ability to adapt essential cost drivers and shorten the development time.
S2TEP development focus
The S2TEP avionics introduce a variety of innovative features; a modular and flexible architecture; as well as novel design and verification processes like:
Modular and scalable design
of the S2TEP bus
The DLR developed avionic components will be flown on S2TEP as either technology demonstrations or bus components, depending on their degrees of maturity.
S2TEP based missions will offer an ideal test environment for technology demonstrations and research within the field of avionics, and thus contributing significantly to the gain of comprehensive and deep design understanding within this field.
S2TEP technology exchange
The technologies developed for S2TEP are also used on the COMPSAT platform; their high degree of scalability creates a synergy between both platforms; enabling technology exchange and allows for a high degree of reusability.
Technologies which are flown on COMPSAT as secondary payloads can later be flown on S2TEP as critical bus components, and vice versa, making both platforms test beds for new developments.
To maintain a high level of flexibility, on both component and system level, the research and development work is focused mainly on scalability in terms of performance, adaptability and reliability. The S2TEP philosophy is further explained below, using two of the developed technologies as examples; the modular software platform and the scalable on-board computer.
Scalable On-Board Computer
The Compact On-Board Computer (COBC) is easily adaptable and can be customized to fulfil a large range of control and data processing requirements. The generic design of the computer facilitates the usage of electric components of different qualification levels, adds the ability to change processor performance, memory size and type, as well as the number and type of interfaces. The on-board computer will be flown on the first COMPSAT satellite Eu:CROPIS as a technology experiment, and after in-orbit verification, on S2TEP as part of the bus, and on the second COMPSAT mission as the payload computer.
Modular software platform
The Open modUlar sofTware PlatfOrm for SpacecrafT (OUTPOST) was originally developed for the on-board computer COBC, but is now also being used for the S2TEP and COMPSAT platforms, as well as in sounding rockets and launchers.
The usage of abstraction layers, towards hardware and operating system, creates a strong foundation for modular and portable implementations of flight software.
The key elements of OUTPOST have been released under an open-source license; available to private and industrial users, for possible joint further developments.