Published: April 22, 2021 By

High-stakes Subterranean Challenge puts Boulder robotics team to the test.

Michael Ohradzansky at the starting line of the Washington challenge course.
Michael Ohradzansky at the starting line of the Washington challenge course.

For mechanical engineering PhD candidate Michael Miles, participating in the national Subterranean Challenge robotics competition has provided real-world experience he might not otherwise have gotten during his graduate studies.

“Normally, you are making a robot that just has to work enough for a 3-minute video,” he said. “Then you publish a paper and visit a conference, and you are done. But running these complicated systems for over an hour in tough conditions? That is unlike robotics anywhere, and it keeps you humble.”

Boulder is one of several funded teams in the Sub-T Challenge, a high-stakes competition launched by the U.S. Defense Advanced Research Projects Agency to test ideas around autonomous robot use in difficult underground environments during search and rescue.

’s team is dubbed Multi-agent Autonomy with Radar-Based Localization for Exploration (MARBLE) and includes engineers from Denver and Scientific Systems Co. Inc.

Each leg of the multiyear challenge tests how autonomous robots acting as first responders approach tunnels, caves and urban environments. That includes handling environmental factors like difficulty communicating through walls or unseen dangers like spilled hazardous material. MARBLE’s team of drones could provide answers to those issues by searching quickly, independently and without fear of the personal physical harm a human would have to consider.

The competition’s second challenge was in February 2020 near Seattle, with the October 2020 challenge shifted to a virtual setting. The final event is scheduled for this summer.

Sean Humbert, a professor in the Paul M. Rady Department of Mechanical Engineering, leads the Boulder team. The students range from undergraduates to PhD candidates and come from computer science, and mechanical and aerospace engineering.

“This competition is good company to be in,” he said. “The top teams in this challenge are well funded and have 30 or more professional engineers, researchers and students, where the core of our team is 10 to 15 graduate students. So our ability to rise to the occasion and compete is something we are truly proud of.”