Meteoroid and space Debris Detector (MDD) flight experiment on the Cosmos upper stage

摘要

In the last decade a number of Meteoroid and space Debris Detectors (MDD) were developed and flown on various space missions to perform in-situ measurements of the MM/SD-environment in dedicated orbits. These detectors were characterized by very specific and rather complex designs. Due to the cost, volume, mass and other required interfaces of these detectors, the number of missions with this kind of detector was strictly limited.rnOHB-System and EMI will perform a MDD flight experiment on the upper stage of a Russian Cosmos-rocket in October 2005. The experiment will be performed in a Sun-synchronous orbit with 680 km altitude. The design of the detector itself as well as the data acquisition system and data downlink follow a new approach with the guiding design principle of simplicity and cost reduction. The detector as well as the data transmission system utilise for this experiment off-the-shelf available components. The large size of the detector in combination with the sensitivity of it will allow for the detection of about one impact per week in the designated orbit. The measured data will be combined with the position and attitude of the Cosmos upper stage and then transferred to a controller and data transmitting unit, which utilises an existing satellite network for data transmission. The data is transferred to one of the satellites, downlinked and then forwarded to the user via a standard E-mail account. No dedicated ground stations are necessary, since the existing infrastructure (Orbcom-stations, www and standard PCs with internet access) are used at low cost for data transmission in near-real time. The same infrastructure can also be used to transmit commands to the MDD, e.g. to verify the detector integrity or to adjust in-orbit detection thresholds.rnIf the flight experiment shows the feasibility of the concept, a variety of applications may materialise. The detector itself with simple mechanical interfaces can be easily adjusted to various carrier vehicles, either upper stages or satellites. The sensor package and the controller and data transmitting unit may be operated independent from other spacecraft subsystems, requiring only electrical power and a mechanical interface. In the future, this equipment described above may be used as a standard sensor package on any spacecraft, performing a drastically improving capability to perform in-situ measurements of MicroMete-oroids and Space Debris (MM/SD) and improving our knowledge on space debris, its spatial distribution and growth. The system may also be developed in a way to directly monitor MM/SD-impacts in the spacecraft structure, by distributing the applied sensors at critical positions on the spacecraft structures. Other events causing "structural noise" like temperature changes may also be monitored. The paper gives an overview of the overall flight experiment, the design and qualification of the MDD, the predicted MM/SD environment and the data acquisition and transmission system. First results of the initial in-orbit phase are presented as well. Further, an outlook on future applications of the system will be provided.