The European Space Agency (Esa) has tested a concept to deliver a rover to the surface of Mars using a quadcopter.
Inspired by the Skycrane that lowered Nasa’s Curiosity on the Martian surface about two years ago, Esa has called engineers from across Europe to propose an innovative Martian landing concept as part of its StarTiger initiative.
Featuring precise navigation capability, the concept, called Dropter, was tested at Airbus’s Trauen site in northern Germany.
“StarTiger is a fresh approach to space engineering,” said Peter de Maagt, who oversees the project on behalf of Esa. “Take a highly qualified, well-motivated team, gather them at a single well-equipped site, then give them a fixed time to solve a challenging technical problem.”
During the eight-month project, teams from the German Research Centre for Artificial Intelligence, Portuguese company Spin.Works aeronautics, and Poland’s Poznań University of Technology Institute of Control and Information Engineering were meeting regularly at Airbus’s facilities in Bremen, Germany.
The team started from scratch, developing a complex vision-based navigational system and hazard detection and avoidance capability for the dropship.
The goal was to develop a system capable to identify a safe landing site and a height from which it could winch down its payload – a mock Martian rover - using a set of cables.
During the testing, the drop ship first flew at a maximum height of 17m before descending to about 10m above the ground, where it began lowering the rover on a 5m-long bridle. After dropping the rover gently onto the surface, the dropship would then return to its cruising altitude.
For the purpose of the testing, a 40m by 40 m Mars-scape was created, littered with hazardous rocks, among which the dropship had to pick a safe spot to deliver its payload.
The dropship itself was built using commercially available quadcopter components, with a smaller drone used for preparatory indoor testing.
The quadcopter first navigated into the correct position using GPS and inertial systems before switching into the vision-based navigation mode supplemented by a laser range-finder and barometer to land its rover autonomously.
Having proved the viability of the concept, Esa will further explore the idea for use in future planetary missions.