May 30, 2016 @ 21:40 | DFKI, Germany |
Looking for life in our solar system is of great interest. A promising candidate for this search is Jupiter’s moon Europa, as a deep-water ocean is assumed to lie under several kilometers of ice which could support extraterrestrial life. Reaching and exploring this ocean is investigated by researchers at the Robotics Innovation Center of the German Research Center for Artificial Intelligence (DFKI). In order to simulate analogous missions on Earth, they have developed an autonomous underwater vehicle (AUV) that can navigate safely through the water using a variety of sensors, along with an IceShuttle that the AUV uses as transportation through the ice and further as a base station. The systems will be on display from 1 to 4 June 2016 at the ILA Berlin AIR show at DLR Space Pavilion, Hall 4.
The goal of the project Europa-Explorer was to show that a robot team can autonomously explore Jupiter’s ice moon Europa based on terrestrial scenarios. The Europa-Explorer project was started on 01.12.2012 and completed on 30.04.2016.
To get an idea of the environmental conditions, especially at the lunar surface, the DFKI researchers consulted data from the Göttingen Max Planck Institute for Solar System Research. Conjectured beneath the ice of the moon, below about 100 kilometers of water depth, are hydrothermal vents that support life through the supply of warmth and minerals to otherwise cold and dark places. To reach this, an exploration vehicle must penetrate through the mighty ice sheet on the surface of the ocean. This is achieved by means of a carrier system which pierces through the outer crust of ice, which becomes a base station and interface to scientists on Earth.
For this scenario, the DFKI researchers have developed the AUV Leng and the Teredo IceShuttle. Leng was designed as a long-range exploration vehicle. Its shape is specially adapted to meeting the mission requirements: the smallest possible diameter to fit in the IceShuttle, and a hydrodynamic profile to allow low-energy travel. The IceShuttle acts as a melting probe which transports the AUV through the ice with the aid of a thermal drilling mechanism. In order to minimize the energy required during drilling, a bore hole with the smallest possible cross-section is desired. Consequently the IceShuttle must be as narrow as possible. A particular focus of the project was the navigation capability of the underwater vehicle. To precisely locate itself, Leng is equipped with a variety of navigation sensors. Utilizing sound signals from the base station, the vehicle can determine its position similar to GPS. Based on the distance and angle of the signal, the system can calculate its position and can come back to the base station, where it can transmit the information collected via an interface to the IceShuttle and recharge its batteries. All of this must happen without control from Earth. The delay in communications with Earth is 33 to 53 minutes – too long to react spontaneously to new situations.
The unique laboratory facilities of the DFKI such as the Maritime Exploration Hall have allowed the researchers to fully develop and test the systems on site. Mission scenarios were simulated in the test basins under realistic and controlled conditions and components were checked in the pressure chamber for deep-water capability. The project, which ended on April 30, 2016 was granted approximately 1.5 million euros from the German Aerospace Center (DLR) with funds from the Federal Ministry for Economic Affairs and Energy (BMWi), over a period of 3 years and 4 months. In possible follow-up projects, the researchers want to test the functionality of the developed Europa-Explorer systems beyond the lab in more realistic environments such as the Arctic.
- Image -1: The AUV Leng in the Maritime Exploration Hall of the DFKI in Bremen. (DFKI GmbH, Photo: Marius Wirtz)
- Source: DFKI in Bremen