“A legged robot needs to be able to detect what is happening when it interacts with the ground underneath, and rapidly adjust its locomotion strategies accordingly,” said Feifei Qian, a faculty at the USC Viterbi School of Engineering and School of Advanced Computing and the project lead in a statement.

Prepping Spirit for planetary exploration

Spirit was field tested by a team comprising engineers, cognitive scientists, geoscientists, and planetary scientists as part of the LASSIE Project, or Legged Autonomous Surface Science in Analog Environments.

According to researchers, the exercise was part of learning more about the characteristics of the substrate and how to walk more skillfully on these terrains. Spirit recorded practice time that will be used to train robots for use on the moon, planets, and possibly surfaces beyond our solar system.

“When the robot leg slips on ice or sinks into soft snow, it inspires us to look for new principles and strategies that can push the boundary of human knowledge and enable new technology. We learn and improve from the observed failures,” said Qian.

The team claims that a legged robot can sense just like we do when walking on uneven surfaces: we can feel the ground moving beneath our feet.

Spirit, under the supervision of the team, refined its movement capabilities from the sandy beaches of Southern California to the soft granules of White Sands National Park in New Mexico.

However, researchers claim that the footage captured at Mount Hood showcases surreal and otherworldly environments analogous to other planets. These earthly trials offer Spirit ample opportunities to learn and adapt before embarking on potential explorations beyond our world.

Robots collaborate for exploration

Qian’s team plans to develop more quadrupeds to further the mission. NASA awarded her a two-year $2 million grant which she and her old Penn colleagues dubbed the TRUSSES Project: Temporarily, Robots Unite to Surmount Sandy Entrapments, Then Separate.

Their goal is to assist the space agency in deploying groups of robots to the moon so they can cooperate to complete missions. These would exchange knowledge on their pre-existing expertise as well as information gathered throughout the mission.

“They would sense how the ground conditions are and then exchange that information with one another, and collectively form a map of locomotion risk estimation. The team of robots can then use this traversal risk map to inform their planetary explorations: ‘There is an extremely soft sand patch that might be high-risk for wheeled rovers. Come over here, this might be a safer area’,” said Qian.

The robotic team envisions a wheeled rover for heavy payloads and long distances, a hexapedal robot for intermediate payloads and improved mobility, and a rugged dog-like robot, similar to a robust version of Spirit, offering high mobility over shorter distances.

According to researchers, the most fascinating aspect of this research is the robots’ ability to transform into structures like bridges or pyramids. This allows the rescue of a teammate stuck in difficult terrain, reminiscent of something out of Transformers or a scenario from “Survivor.”

“When they plan for the strategy to pull the robot up, they’ll decide what force to exert and what position the robot should go to, while also compiling the terrain information,” Qian said.

“That’s the key idea of how to use these capabilities: to both prevent and recover from locomotion failures in extreme terrain,” she added.