Then the team scaled up, including adding a rectangular head mounted on a 4.5-foot-tall (1.4-meter-tall) mast. The hardware was completed in September 2024, but the rover still needed a human operator to joystick it, sending commands to instruct the rover on how to move over obstacles.
In order to train the rover to think on its own, the ERNEST team turned to reinforcement learning, a type of artificial intelligence where the robot learns by interacting with its environment. The Dynamics and Real-Time Simulation Laboratory at JPL developed a high-fidelity virtual testing environment that replicates the rover’s behavior. The team fed the simulator data collected by engineers who documented the response of the actual rover hardware to a variety of terrain types. On a high-performance computing cluster, the team ran many simulations at once, sometimes completing thousands of hours of tests over a single weekend.
After months of virtual training, the ERNEST team was ready to see if the rover could use its new autonomous algorithms to figure out how to drive over terrain features that would halt a passive-suspension rover. They set up an obstacle course with sand ripples, rubble piles, steps, and steep slopes in JPL’s Mars Yard, an outdoor terrain proving ground. Then they watched as the rover maneuvered the terrain on its own. Since then, ERNEST has completed many such courses.
Nayar’s team is starting a new autonomy project which involves integrating the rover’s ability to determine when and how to use its active suspension with longer-range intelligent navigation. The goal is to enable ERNEST to plan an efficient path so that it can tackle surmountable obstacles and circumnavigate hazardous ones. These capabilities could contribute to potential future rover missions encountering formidable landscapes on Mars or more rugged areas of the Moon.
Work on ERNEST began in 2022 was initially supported by JPL internal research and development funds. It is currently funded by NASA’s Mars Exploration Program and the agency’s Exploration Science Strategy and Integration Office in its Science Mission Directorate at NASA Headquarters in Washington. Caltech in Pasadena, California, manages JPL for NASA.