Researchers uncover the issue hampering grounded rovers with the aid of open-source tools
In a groundbreaking discovery, researchers at the University of Wisconsin-Madison have uncovered a critical flaw in conventional rover testing protocols for extraterrestrial exploration missions. Their findings, published in the Journal of Field Robotics, have the potential to significantly improve the accuracy and reliability of Earth-based simulations for lunar and Martian exploration.
The root of the issue lies in the way rover testing is currently conducted. Traditionally, the weight of the rover is reduced to mimic lunar or Martian gravity, such as one-sixth Earth’s gravity for the Moon. However, these tests are carried out in Earth soil, whose physical response does not reflect reduced gravity. This oversight overlooks the fact that lunar regolith shifts more easily and offers reduced traction under lunar gravity, unlike Earth’s compact soil.
The researchers' simulations showed that soil mechanics under low gravity are substantially different and matter significantly for rover mobility. By considering gravity’s effect on both rover and soil, they achieved improved simulation fidelity. In some cases, this may even obviate the need to scale down rover mass in Earth tests if soil conditions are properly modeled.
To address this issue, the team developed an open-source physics simulator called Project Chrono. This tool provides new capabilities to model both rover and terrain under extraterrestrial gravity, enabling better design and testing of rovers before launch. This advance was crucial in diagnosing potential issues that affected missions like NASA’s VIPER, which was terminated due to traction problems identified through this research.
In addition to its application in space exploration, Chrono software is also used by various institutions such as NASA's Jet Propulsion Lab, the U.S. Army Ground Vehicle Systems Center, the U.S. Army Engineer Research and Development Center, and the National Renewable Energy Lab. It has even been deployed for "miniaturized mechanisms for watches." The experts at the Politecnico di Milano in Italy used Chrono for the Mascot lander for its asteroid Ryugu mission.
Moreover, Chrono software is used for estimating the off-roading capabilities of US Army vehicles. The team at UW-Madison is currently working on simulation modeling for NASA’s VIPER rover.
The implications of this research are far-reaching. By integrating terramechanics models that simulate gravity’s dual effect on vehicle and terrain, the team at UW-Madison is paving the way for more accurate and reliable Earth-based simulations for lunar and Martian exploration missions. This advance will help engineers to design rovers that can traverse extraterrestrial surfaces more effectively, thereby preventing potential issues such as those that led to the abandonment of missions like the Spirit rover in 2009 or NASA’s Mars Exploration Rover Opportunity in 2005.
In conclusion, the University of Wisconsin-Madison's research is a significant step forward in the field of extraterrestrial exploration. By addressing a critical flaw in conventional rover testing protocols, the team is ensuring that future missions will be more successful and reliable.
- The study conducted by researchers at the University of Wisconsin-Madison in the field of environmental science, specifically space and astronomy, has revealed a significant improvement in the design and testing of rovers, thanks to the development of open-source physics simulator, Project Chrono.
- This advancement in technology, Project Chrono, is not only transforming the landscape of space and planetary exploration, but is also being utilized in various domains, such as miniaturized mechanisms for watches, off-roading capabilities of US Army vehicles, and modeling for NASA's VIPER rover, demonstrating its wide-ranging applications.
