Defective tests on earth can explain why NASA Rovers are stuck on Mars

In the spring of 2019, the Spirit Rover with six -wheelers led back to slide an inoperable right front wheel when it was stuck on the sandy Martian surface. Despite months trying to search its robot, NASA could not release the mind. Now, engineers from the University of Wisconsin – Madison may have found a way to better prepare NASA robots for extraterrestrial environments.

In an article published in the Journal of Field Robotics, The team of engineers used computer simulations to discover a missing element in the way NASA tests its Rovers on Earth. Rather than taking into account the effect of gravity on the prototypes of rover tested on earth, the engineers behind the recent study suggest that NASA has neglected the attraction of gravity on the sand itself.

The severity on Mars is much lower than on earth. To take into account the difference in severity between Mars and Earth, NASA engineers test a light prototype of Martian Rovers which are about a sixth of the mass of robots sent to the Red Planet. The recent simulations, however, revealed that the gravity of the earth stops on the sand much more strongly than on Mars or the Moon. Consequently, the sand on earth is much more rigid and less likely to move under the wheels of the rover, when it tends to be softer on the moon.

“We must consider not only the gravitational attraction on the rover, but also the effect of gravity on the sand to obtain a better image of how the rover will occur on the moon,” said Dan Negrut, professor of mechanical engineering at Uw – Madison and the main author of the newspaper, in a press release.

The team behind the study tripped on the missing piece of the puzzle while simulating the viper of NASA, or volatiles investigating Polar Exploration Rover, which was to start the moon this year before the cancellation of its mission. While simulating Viper’s mission, the engineers noticed differences between the earth tests of the Rover prototype and the simulations based on the physics of the four -wheeled robot on the moon.

The new discoveries suggest that Rovers on extraterrestrial terrains, like the Moon or Mars, are more likely to fight against the wheels stuck in less cooperative sands. Something like that can have happened not only in Spirit, but also in the opportunity of NASA, which spent weeks stuck in sand in 2005, and curiosity, which bogged down on soft ground in 2014. Considering how the sand behaves under the lighter gravitational attraction of other worlds, NASA can better prepare its robots on the severe field to come.