The Institute of Space Systems is concerned with space technology.
Space technology is concerned with the orbital mechanics of satellites in medium Earth orbit. The research focuses on the exact calculation of satellite orbits, taking into account all the disturbing forces, predicting the path and the reentry of small satellites as well as the simulation of the formation and distribution of space debris (Space Debris) including the detection of object distribution densities for satellites, rocket stages and debris in near-Earth space.
The basis of the institute's spaceflight technology work is knowledge and application of general and higher orbital mechanics. The main research consists of the orbital dynamics of all objects on Earth orbits (space debris), orbit survey and orbit prediction, especially for light satellites and the re-entry of hazardous objects. The research fields of the astronautics cover:
Precise calculation of satellite orbits including all involved forces.
Trajectory and re-entry prediction of light satellites.
Space debris: Determination of object distribution densities for satellites, rocket stages and debris particles in low Earth orbits; calculation of collision probabilities.
Based on the long standing experience the institute received the contract from the European Space Agency (ESA) to develop the MASTER model (Meteoroid and Space Debris Terrestrial Reference Model) for analysis of collision risks with space debris and natural meteorites. MASTER allows users from the European astronautics industry to estimate the collision risk. Special data compression methods and an efficient analysis software allows storage of the huge amount of data on a single CD-ROM and fast processing on most of the popular operating systems. Meanwhile, the MASTER model has been completed and is being distributed by the ESA on CD-ROM to European companies and institutes. MASTER is used by the industry to estimate the time- and height-dependent risk for missions and to design shieldings for the space station. Internationally it serves as a basis for the coordination of countermeasures against the ongoing congestion of the near Earth space, which have to be implemented by all space travelling countries. Meanwhile the model is being used worldwide and is compared with the corresponding NASA model.
The workgroup satellite technology was founded in the course of the restructuring of the Institute of Space Systems. The Satellite Technology group examines the active removal of space debris. The main research areas include:
- Orbit and attitude control of spacecraft
- Docking with non-cooperative targets
- Development, testing and operation of small satellites
- Development of novel docking mechanisms
In the long term, the group plans the development of small satellites for on-orbit testing and verification of research results. For this purpose, the necessary infrastructure consisting of a satellite integration room and a ground station for communication is being established.
New mission concepts for the implementation of "Active Debris Removal" are designed. In particular, uncooperative targets such as tumbling rocket upper stages are considered. These are to be stabilized via the docking of a servicer and thus prepared for a controlled re-entry. The focus here lies particularly on the multibody dynamics and attitude control in space.
A docking mechanism for the servicer is under development on the basis of biologically inspired materials. Mechanisms based on adhesive bionic materials which mimic the properties of gecko feet are investigated.
To validate the docking mechanism, as well as navigation techniques, a test environment is set up consisting of an air-bearing table, a robotic arm and several testing bodies (simulated experimental satellites). It is noteworthy that the experimental satellites do not require separate supply of compressed gas and thus long-term simulations are possible.