System for multi-robotic exploration of underground environments CTU-CRAS-NORLAB in the DARPA Subterranean Challenge

Abstract

We present a field report of the CTU-CRAS-NORLAB team from the Subterranean Challenge (SubT) organized by the Defense Advanced Research Projects Agency (DARPA). The contest seeks to advance technologies that would improve the safety and efficiency of search-andrescue operations in GPS-denied environments. During the contest rounds, teams of mobile robots have to find specific objects while operating in environments with limited radio communication, e.g., mining tunnels, underground stations or natural caverns. We present a heterogeneous exploration robotic system of the CTU-CRAS-NORLAB team, which achieved the third rank at the SubT Tunnel and Urban Circuit rounds and surpassed the performance of all other non-DARPA-funded teams. The field report describes the team’s hardware, sensors, algorithms and strategies, and discusses the lessons learned by participating at the DARPA SubT contest.

Virtual Reality via Object Pose Estimation and Active Learning: Realizing Telepresence Robots with Aerial Manipulation Capabilities

“…For example, Saska et al (2017Saska et al ( , 2014 pioneered the area of swarm robotics, while Loquercio et al (2021); Foehn et al (2022) demonstrated impressive results in agile flights of micro aerial vehicles. Aerial robotics, with fully on-board perception, has also been part of the recent DARPA subterranean challenges (Rouček et al, 2022;Tranzatto et al, 2022;Agha et al, 2022;Hudson et al, 2022). Vision based localization methods have also made tremendous progress (Ebadi et al, 2022;Weiss et al, 2012;Scaramuzza et al, 2014;Lutz et al, 2020).…”

MRS Drone: A Modular Platform for Real-World Deployment of Aerial Multi-Robot Systems

“…The requirement of a significant sensory payload competes with the need for minimization of the UAV in order to traverse such constrained corridors, as well as the need for a long flight time, in order to get to the furthest parts of the searched space. Throughout the five-yearlong competition, the platform developed evolved significantly [43,64,67,74], with each iteration improving upon the last. The platform developed for the final event of DARPA SubT was based on the compact and lightweight Holybro X500 quadrotor frame.…”

Lessons learned: Symbiotic autonomous robot ecosystem for nuclear environments

“…A tracked robot shut down on a stairway, when the tracks slipped, this caused a crash and the HITL was forced to shutdown the robot. The same team also faced a catastrophic failure post mission due to the condensation which had built up during the event leaving a Clearpath Husky with problems after the event [76]. In advance of the DARPA SubT challenge, many teams knew they would face robotic failures and so had designed different approaches in advance.…”

“…For example, Rouček et al . [76], utilised software which allowed for failures and tried to mitigate them when they occurred. Agha et al .…”

“…A husky robot was freed to overcome navigational challenges by a tracked robot. The tracked robot was rammed into the Husky to dislodge it, however this resulted in a negative interaction as although the Husky robot was now operational, the tracked robot now displayed a failure as it had lost its location in the map it had constructed [76].…”