Many of the great challenges of our time, including climate change, ensuring public safety, support in emergency, and being connected everywhere at any time, will require innovations in satellite technology. Faster reactions, more flexibility, accuracy and cost-efficiency are needed, if we are to successfully confront these challenges. NetSat is about to make a crucial step into this direction by distributed, cooperative control.
At noon on 28. September 2020 a Soyuz-Rakete will lift-off into orbit with three Russian Gonets telecommunication satellites and 19 small satellites. Also included are the four NetSat pico-satellites from Würzburg. At the size of a shoebox with a mass of 4 kg each, their objective is to test first time all crucial techniques for optimal self-organization of a satellite formation in a three dimensional configuration. This will not only enable new approaches to Earth observation, but also to future telecommunication networks – while reducing the high costs that hamper today’s space missions.
The four pico-satellites are already integrated in the Soyuz rocket in the Russian cosmodrom Plesetsk. On 28.9. they will be transferred into an orbit at 600 km altitude. "The scientific objective is the capability to autonomously coordinate and control the formation in order to realize an optimum configuration in three-dimensional space for observations," Professor Klaus Schilling explains, who received 2,5 Mio € for groundbreaking research in networked control in space through a distinguished Advanced Grants from the European Research Council (ERC). The significant application potential of this mission was supported by additional funding through the Bavarian Ministry of Economics.
The satellites were realized by the Center for Telematics (ZfT) in Würzburg in cooperation
with the start-up company S4 – Smart Small Satellite Systems GmbH because of its outstanding test infrastructure for multi-satellites-systems. "In addition to the extreme technology challenges in the areas of miniaturization, and attitude / orbit control, our team had to handle COVID-19 related complications for delivery of components from all over the world" emphasizes Daniel Eck, CEO of ZfT. The satellites use a very efficient electrical propulsion system (from the Austrian company Enpulsion) and very small precision reaction wheels (from S4–Smart Small Satellite Systems and Wittenstein Cyber Motor) to achieve high accuracy pointing. The radio link between satellites supports data exchanges with respect to position, pointing and planned maneuvers. This enables coordination of the four NetSat satellites in combination with advanced networked control methods. While the long-term task planning is done by the ground control center in Würzburg, the reaction on disturbances and fine tuning of the formation is realized autonomously by software on-board the satellites.
In July the satellites left ZfT / S4 facilities in Würzburg, were integrated in the launch adapters and tested again. Finally the launch provider Exolauch delivered them to the launch site in Plesetsk, where it was fixed on the Soyuz rocket.
The inovative further use of NetSat results is assured by already-contracted future application missions in Earth observation (TIM, TOM) and climate prediction (CloudCT). Thus, it is expected that the information for decisions in emergency situations and for challenges like climate change will be improved by networks in orbit composed by many small satellites.