The Chair of Aerospace Information Technology at the University of Würzburg has developed a Space Maneuvering and Docking Facility in order to help researchers and students understand and get familiar with basic spacecraft and satellite subsystems and also to develop and test different control algorithms and strategies for space rendezvous, docking and formation flying in a frictionless, space-like environment. This facility is being used extensively by our researchers in various projects, as well as by our postgraduate and undergraduate students in their thesis work.
The SMD vehicle consists mainly of a mechanical structure, which is supported by flat circular air bearing pads which produces frictionless motion on a flat and smooth surface of glass plates for microgravity environment. The propulsion subsystem of the vehicle consists of compressed air supply tanks with proportional valves to control the flow rate and pressure release nozzles as actuators. A star tracker based position and attitude determination system is used to navigate the vehicles in the facility. An autonomous docking process between two vehicles is performed with the help of on-board optical sensors used to determine the attitude and the distance of the target vehicle. In order to monitor and control the SMD system, a ground station computer is used to communicate via Wi-Fi modules available in the vehicles through commanding and telemetry display tool.