Tunnelling robot ushers in new era for urban maintenance
Repairing damaged water pipes and laying high-speed internet cables are a fact of urban life. To access underground pipes and cables, trenches need to be dug. Though such infrastructure maintenance is essential to ensure cities maintain a high standard of living, the resulting road blocks, traffic jams and increases in pollution can make city life at times stressful and unpleasant. “We realised that there was no drilling technology capable of autonomously navigating and exploiting underground workspace,” explains BADGER project coordinator Carlos Balaguer, professor at the Robotics Lab, University Carlos III, Madrid, Spain. “This means that underground installations or inspections require the excavation of large surface areas. This can be expensive and disruptive.”
Tunnel vision
The BADGER project sought to address this challenge by developing intelligent tunnelling machinery, capable of carrying out urban infrastructure works with minimal disruption. To achieve this, existing trenchless excavation and environment mapping technology was combined. “We were inspired by robotic space technology,” notes Balaguer. “Our vision was of BADGER autonomously navigating the subsurface world by removing and pushing through subsurface soil, while at the same time using advanced sensing techniques to localise itself and make operational decisions.” The robot itself has a modular structure, with multiples degrees of freedom to move in the bio-inspired manner of a worm. A smart on-board and surface Ground-Penetrating Radar (GPR) detects obstacles, and automatically generates the robot’s path. This means that the BADGER robot can autonomously navigate around multiple obstacles such as rocks, pipes and building foundations. After developing a network of small-bore tunnels, the robot can detect, inspect and assess the state of buried utilities, as well as map and visualise the 3D underground space. Robust industrial drilling tools are integrated into the robot, which means that repair tasks can be carried out in this underground space.
Artificial intelligence underground
The project was successfully tested in Lennestadt, Germany, as well as in Madrid, Spain. Both demonstrations provided contrasting soil conditions and weather. “In both situations, the robot was programmed to produce several small tunnels at different angles,” says Balaguer. “These tunnels, only about 225 cm in diameter, are sufficient to enable maintenance work to be carried out, without the need to dig up trenches. This technique has the potential to drastically reduce pollution, noise, traffic congestion, and thus inconvenience for citizens.” Balaguer sees potential in BADGER for being used as a critical support tool for service professionals above ground. “A control console communicates with the underground robot either through wired connection or wirelessly, using transmitters installed along the tunnel,” he adds. “Massive data gathered during underground operations means that the robot can continuously improve its perception and cognition abilities. This data can also be stored and analysed to enable efficient offline planning and online remote monitoring and control of the overall operation process.” The BADGER team is currently evaluating potential new applications for the BADGER robot, together with several companies. These applications include horizontal oil field characterisation and inspection, field exploration for geothermal energy and even rescue applications for natural and artificial disasters.
Keywords
BADGER, infrastructure, drilling, traffic, tunnels, congestion, geothermal, robot
