A Halloween view inside one of the darker recesses of ESA’s technical heart. Shaded to resemble the blackness of deep space, the GNC Rendezvous, Approach and Landing Simulator, or GRALS, is seen being used to test vision-based navigation algorithms under development for the proposed Hera binary asteroid mission.
A camera, mounted on a robot arm that moves along a 33-m long track, approaches a pair of 3D-printed asteroid models.
Hera, Earth’s first mission to a binary asteroid system, would use vision-based algorithms to map surface features on an automated basis to plot its position in space and plan its onward route.
To simulate space, the chamber is kept dark for the testing, except for a single Sun-like light source.
Part of the Agency's Orbital Robotics and Guidance, Navigation and Control Laboratory in its ESTEC technical centre in the Netherlands, GRALS is used to simulate close approach to uncooperative targets such as asteroids or drifting satellites.