Safeguarded Teleoperation for Lunar Rovers: From Human Factors to Field Trials

In this paper we present recent advances in developing and validating the safeguarded teleoperation approach to time-delayed remote driving. This approach shares control of the rover using a command fusion strategy: In benign situations, users remotely drive the rover; in hazardous situations, a safeguarding system running on-board the rover overwrites user commands to ensure vehicle safety. This strategy satisfies users, because it allows them to drive (except in hazardous situations), while maintaining the integrity of the rover and mission. We present results from experiments on untrained teleoperators with and without safeguarding, which reveal needs to be met by future user interfaces. We describe three technical advances in safeguarding: improving the accuracy of dead reckoning by a factor of 2, speeding up the controller by a factor of 18, and developing an area-based rather than a path-based obstacle avoidance planner in order to circumvent map merging problems. Finally, we discuss a field trial validating the approach in a 10 km traverse, demonstrating the effectiveness of safeguarding, even with malicious drivers.