What methods and simulations can engineers use to accurately test rovers that are used on other worlds like the Moon and Mars? This is what a recent study published in the Journal of Field Robotics hopes to address as a team of researchers investigated new methods for testing rovers on Earth so these brave explorers will perform better under reduced gravity environments. This study has the potential to help scientists, engineers, and mission planners develop novel strategies for improving robotic space exploration and the science these explorers can accomplish.
For the study, the researchers examined a novel technique called gravitational offsetting, which involves a simulator designed to observe and document how rovers perform under reduced gravity conditions. They used an open-source physics simulation called Project Chrono designed to model complex mechanical systems to simulate how NASA’s VIPER rover would function on the Moon. The goal of this study is to present the effectiveness of gravitational offsetting using physics-based models while making a case that current methods used to develop and test rovers on Earth are insufficient for preparing them to work on other worlds under low-gravity environments.
In the end, the Chrono simulations revealed several flaws with how VIPER was tested on Earth, as the current testing methods didn’t match the simulations. The flaw included how researchers failed to account for the Earth’s gravity pushing down on the sand the rovers were tested on, whereas the Moon and Mars have one-sixth and one-third Earth’s gravity, respectively.
“In retrospect, the idea is simple: We need to consider not only the gravitational pull on the rover but also the effect of gravity on the sand to get a better picture of how the rover will perform on the moon,” said Dr. Dan Negrut, who is a professor of mechanical engineering at UW–Madison and a co-author on the study. “Our findings underscore the value of using physics-based simulation to analyze rover mobility on granular soil.”
Image of Dr. Dan Negrut with rovers that were tested for the study. (Credit: Joel Hallberg / UW–Madison)
How will gravitational offset help engineers test space exploration rovers in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Journal of Field Robotics, EurekAlert!
