Manuel Czech’s research while affiliated with Technical University of Munich and other places

On October 22nd 2008, the VERTICAL (VERification and Test of the Initiation of CubeSats After Launch) experiment was flown on the REXUS 4 sounding rocket mission at Esrange in Kiruna, Sweden. The experiment’s objective was to verify critical hardware to be used on the MOVE CubeSat in a space environment. The items to be verified were multiple micro switches from different manufacturers and a solar panel deployment mechanism developed at TUM. The deployment mechanism is triggered by a melt wire. During launch, the switches are depressed by a plate which is retracted once the rocket is near its apogee. This simulates the satellite’s ejection from the launch vehicle. The verification sequence was executed as planned during the 10-min flight and the experiment was safely recovered. The acquired data suggests that the deployment mechanism can be used as is and COTS of verified quality micro switches will survive LEOP conditions and are suitable for further testing, addressing their long-term reliability.

MOVE (Munich Orbital Verification Experiment) is a program of the Institute of Astronautics (LRT) at the Technische Universität München (TUM), which aims on building pico-satellites with university students mainly for educational purposes. First-MOVE shall create a robust platform as a starting point for sophisticated satellite missions of the institute in the future. In the paper, the state of development is described, but emphasis is on the requirements for high reliability of the First-MOVE satellite and how robustness drives the actual design of the satellite.

On the 22nd of October 2008, EuroLaunch launched the REXUS-4 rocket at Esrange in Northern Sweden. EuroLaunch is a joint venture of the DLR Mobile Rocket Base and the SSC Esrange Space Center. REXUS-4 was a two-stage unguided solid propellant sounding rocket. The vehicle consisted of a Nike motor as 1st stage, an Improved Orion motor as 2nd stage, a motor adapter, a recovery system, a service system, two experiment modules, and a nosecone. The REXUS-4 payload was comprised of five technological experiments from German and Swedish Universities. The rocket was spin-stabilized during the ascent. After the burn-out of the 2nd stage a yoyo system de-spun the rocket to a rate of only a few degrees per second. At an altitude of 71 km the nosecone was jettisoned. The payload reached its apogee at 175 km. The REXUS-4 mission was also the maiden flight of a newly developed rocket service system. After this successful demonstration, it has been implemented into the REXUS/BEXUS programme. This German-Swedish student programme offers annual flights for student experiments on sounding rockets and stratospheric balloons. This paper gives a short overview on the development of the REXUS service system and points out the advantages of using standard interfaces for student experiments. Furthermore it contains a description of the REXUS-4 vehicle, the mission, the campaign and the experiments. Some experiments are described in more detail. During the ballistic flight the MIRIAM experiment of the University of Armed Forces in München and the Mars Society Germany was separated from the main payload to test a balloon system that will be used for the entry of a probe in the Martian atmosphere in the future. Several cameras on the REXUS-4 payload as well as cameras and telemetry on the MIRIAM flight system monitored the separation and inflation during the ballistic flight phase. The VERTICAL experiment from the Technical University München verified the start-up procedures of the CubeSat MOVE and its solar panel deployment under real spaceflight conditions. The paper also gives an overview on the REXUS/BEXUS programme and its chances for students.

On the 22nd of October 2008 EuroLaunch launched the REXUS-4 rocket at Esrange in Northern Sweden. EuroLaunch is a joint venture of the DLR Mobile Rocket Base and the SSC Esrange Space Center. The REXUS-4 payload was comprised of five technological experiments from German and Swedish Universities. The REXUS-4 mission was also the maiden flight of a newly developed service system. After this successful demonstration, it has been implemented into the REXUS/BEXUS programme. This paper gives a short overview on the development of the REXUS service system and points out the advantages of using standard interfaces for student experiments. Furthermore it will contain a description of the REXUS-4 vehicle, the mission, the campaign and the experiments.

In this paper we present the realization of a test environment to test preflight high-fidelity inter-satellite communication links on ground. The basic requirements are given by the research project “Telepresence for Space Missions” as part of a collaborative research centre (SFB 453) funded by the German Research Community (DFG). The intention of this project is establishing a communication link from Low Earth Orbit (LEO) to a geostationary relay satellite in order to control robotic applications on LEO satellites. While about 0.6 seconds. To establish an Inter Satellite Link (ISL) a tracking mechanism for a steerable antenna is needed. To verify the functionality of the tracking mechanism, a test bed has been developed at the Institute of Astronautics using an existing concept of a test bed for an attitude simulation system. This test bed for attitude simulations is based on an antenna turntable which is part of the S-band ground station at the Institute of Astronautics. Using this antenna turntable with 2 degrees of freedom (azimuth, elevation) the simulator design envisages another degree in order to demonstrate possible satellite attitudes. A key point in the design is the easy and fast reconfiguration of the antenna turntable into the attitude test bed. In this paper the constraints for the construction and final realization of this attitude simulator test bed is depicted. It describes all modifications needed to reconfigure the antenna turntable into an attitude simulator system test bed and visa versa. Eventually, the test setup will be illustrated which will be used for the addressed verification.

In this paper we present a test environment to test preflight high-fidelity intersatellite communication links on ground. The basic requirements are given by the research project “Telepresence for Space Missions” which is part of a collaborative research centre (SFB 453 – Sonderforschungsbereich) funded by the Deutsche Forschungsgemeinschaft (DFG). The goal of this project is to analyze and test the possibility of establishing a communication link via a geostationary relay satellite having a signal roundtrip time smaller than 0.8 seconds. To establish a link between a Low Earth Orbit (LEO) satellite and a geostationary relay satellite, an Inter Satellite Link (ISL) tracking mechanism to steer the antenna is needed. To verify the functionality of the tracking mechanism, a test bed similar to attitude control system test beds had to be developed at the Institute of Astronautics. Start-ing from the requirements of the attitude control system for an on-orbit servicing mission, a selection of existing attitude control simulators and their qualities as a simulator for this project will be layed out. In this paper the concept of a more use-ful low-cost satellite attitude control simulator will be presented. Finally, the paper describes all modifications needed to convert an existing antenna turntable at the Institute of Astronautics into the required testbed.

Due to the classification of technologies in NASA’s and ESA’s technology readiness levels, newly developed components have to be space proven before they can be utilized in space missions. This space prove can be adduced by sending these technologies to orbit either as experiment on a piggyback flight or a dedicated mission. Over the last years the size of technologies and satellites has shifted to much smaller sizes. In this paper, the possibility of industrial verification of MEMS (Micro Electro Mechanical System) applications using dedicated pico-satellite missions is examined. Based on the CubeSat concept, a technology verification platform can be realized for verification of not only pico-satellite components, but also of components of complex systems and missions. Therefore a platform fulfilling the requirements for such industrial verification of components named MOVE (Munich Orbital Verification Experiment) is developed at the Institute of Astronautics (LRT). This platform enables professional verification of MEMS technology and techniques at overall mission costs of less than 100k€. As a first application of this approach, a mission called π-MOVE (π for piezo) will verify piezo motors on the developed platform. These piezo motors are representative for components of complex systems, as this motor concept is considered to be key technology for future segmented mirror telescope missions. In the mission design process for this platform, strong emphasis is put on the robustness of the design, low complexity and realizability within the institute’s environment. The advantages through access to both university and industry resources will be taken. The feasibility of professional technology verification is highly dependent on the test plans, which are developed in cooperation with the experienced industrial partners.