A new rover prototype is helping NASA scientists develop robots capable of thinking for themselves and navigating terrain where older rovers would get stuck in lunar or Martian dust. It recently underwent testing in the desert.
Advantages of the New Rover Technology
The Extreme Rovers for Navigating Extreme Sloped Terrain rover, or ERNEST, developed at NASA’s Jet Propulsion Laboratory (JPL), recently completed a 16-mile, or 26-kilometer, trek through the desert in Southern California. The journey took more than 37 hours of driving over seven days, and ERNEST covered the route almost entirely autonomously, with “minimal intervention” from the engineers overseeing the test, according to a JPL statement. This was reported in an article on www.space.com.
NASA hopes that this technology can be implemented in future Mars and lunar rovers, which may one day be able to travel farther and faster than their predecessors by relying on onboard software to assess and navigate hazardous landscapes that were previously inaccessible to robotic explorers.
“These tests are helping us refine the mobility hardware and autonomous software to traverse long distances over a variety of terrain types and lighting conditions expected on the Moon,” Issa Nesnas, JPL’s chief technologist, said in a June 18 statement.
A Rover with Advanced Intelligence and a New Chassis
One of the factors that sets ERNEST apart from its predecessors is its innovative wheels and active suspension system. Combined with adaptive artificial intelligence, the rover is able to recognize obstacles in its path and either avoid them or overcome them while moving toward its next destination.
ERNEST’s intelligence is the result of months of reinforcement learning conducted in a virtual environment, where the rover accumulated thousands of hours of empirical data in just a few days by running numerous simulations simultaneously. Then, to test what it had learned after the virtual trials, the team sent the test rover through an obstacle course at JPL’s Mars Yard before deploying it on the sands of the California desert.
Previous rovers, such as Perseverance and Opportunity on Mars, were designed using a rocker-bogie system, which uses open pivot points to passively distribute weight evenly among six wheels. The four-wheeled ERNEST prototype uses two joints at the front of the chassis that rotate to change the rover’s gait, creating movements that imitate twisting, wheel-walking, and overcoming obstacles, according to the same statement. ERNEST is also able to steer each of its wheels, allowing the rover to maneuver not only forward and backward, but also side to side.
“While the rocker-bogie system has been very successful over the past 30 years, during that time there has been a lot of research into mobility and interaction with terrain,” said Hari Nayar, lead principal technologist for the ERNEST team.
ERNEST Rover Speed
During the week-long tests, which took place in March of this year, engineering teams observed ERNEST’s performance in several navigation scenarios, including driving at night and in other low-light conditions to simulate certain lunar environments.
The rover is 4 feet, or 1.2 meters, long and can travel at speeds of up to 0.6 miles per hour, or 1 km/h. This is significantly faster than the rovers currently operating on the Moon and Mars, such as Perseverance, which after five years on the Red Planet only recently covered a distance equal to a marathon on Earth — 26.2 miles, or 42.2 km.
ERNEST will not fly into space. Its task is to develop new solutions that in the future could make planetary rovers much faster, more autonomous and capable of exploring terrain inaccessible to current robots. Engineers hope that ERNEST will become a model for even larger and more powerful rovers, capable of covering much greater distances and developing higher speeds. The results obtained are planned to be used in the development of the next generation of lunar and Martian missions.
