NASA Tests ERNEST Rover Prototype Capable of Lifting Wheels and Driving 10x Faster

NASA's Jet Propulsion Laboratory has successfully tested a new prototype rover in the Colorado Desert, showcasing a radical departure from the design of its current Mars explorers. The vehicle, named ERNEST, covered 16 miles in just 37 hours of drive time during a recent seven-day field campaign.[1][2][4]

Hitting a top speed of 0.6 mph, ERNEST is roughly ten times faster than the Perseverance and Curiosity rovers currently operating on Mars. While that pace is a slow walk for a human, it represents a massive leap for planetary exploration, where rovers typically crawl to avoid hazardous terrain.[1][2][3]

Since the Sojourner rover landed in 1997, NASA has relied on a passive 'rocker-bogie' suspension system. While highly reliable, it forces rovers to navigate at around 0.06 mph and take long detours around steep slopes or rocky hazards to avoid getting permanently stuck.[1][3][5]

ERNEST—which stands for Exploration Rover for Navigating Extreme Sloped Terrain—solves this with an active suspension system. Featuring two powered joints in the front, the four-wheeled rover can lift individual mesh wheels to step onto or over obstacles that would halt its six-wheeled predecessors.[1][2][5]

This articulation allows ERNEST to utilize unconventional gaits. NASA engineers describe the rover as being able to 'squirm,' 'wheel-walk,' and climb obstacles. With four steerable wheels, it can even drive sideways to navigate out of tight spots.[1][3][5]

The rover isn't always expending maximum energy. A clutch mechanism allows it to toggle between active and passive suspension on the fly, conserving power on flat terrain and engaging the active joints only when the landscape demands it.[1][4][5]

Speed isn't just about motors; it's about decision-making. Because signal delays between Earth and Mars can take up to 24 minutes, rovers must navigate autonomously. JPL trained ERNEST's navigation system using reinforcement learning in a simulation lab before it ever touched the dirt.[1][4]

During the desert campaign, engineers trailed the 4-foot-long prototype as it navigated the rough terrain with minimal human intervention. They even tested it in darkness to simulate the dim lighting of the lunar south pole, a key target for upcoming Artemis missions.[1][4][5]

While ERNEST is currently a small prototype, the JPL team expects a final flight-ready build to be at least double the size. The project, which began in 2022, has already iterated through multiple suspension designs and AI training models.[3][6]

The technologies developed for ERNEST are intended to serve as a testbed for future missions. As NASA looks toward establishing a sustained presence on the Moon and venturing into previously inaccessible regions of Mars, rovers will need to cover vastly more ground.[2][3][5]

As James Keane, a JPL planetary scientist, noted, the vehicle's capabilities could eventually enable a 'science road trip' across the Moon or Mars, fundamentally changing the scale and speed of robotic planetary science.[2][3][6]