Martian Fetch: Finding and retrieving sample-tubes on the surface of mars

Mars Sample Return (MSR) was identified by the 2011 planetary science decadal survey as a high priority long-term goal for NASA. A three-mission campaign concept is currently being investigated. The Mars 2020 rover mission is intended to core and collect samples. These samples will be sealed in tubes and left on the surface for potential return to Earth. In the current MSR campaign concept, a Sample Retrieval and Launch (SRL) mission would collect the sample tubes left by the Mars 2020 rover and load them into a Mars Ascent Vehicle (MAV) to be launched into orbit. The third mission concept involves a spacecraft capturing the samples in Martian orbit and returning them to Earth. This paper focuses on the SRL mission concept to collect the sample tubes, addressing the problem of autonomously detecting, localizing, and grasping sample tubes deposited on the Martian surface. We employ two approaches: The first one is context-based. It would use a high precision map computed from images captured during tube release, to locate the tubes without directly observing them. The second approach directly detects the sample tubes visually and estimates their 6-DoF pose onboard from dense stereo data.