“The Underminer programme aims to develop and demonstrate tactical uses for rapidly created underground infrastructure in contested environments,” said Dr. Andrew Nuss, Underminer programme manager. “The ability to quickly bore tactical tunnels could benefit contingency operations such as rapid ammunition resupply, rescue missions, or other immediate needs.”
Focusing on tunnelling approaches, downhole sensing and operational concepts, the project will seek to merge breakthroughs in horizontal directional drilling, trenchless technologies and robotics. It will try to demonstrate that a robot can move at 100mm/sec to excavate a tunnel 500m long and with a minimum 100mm diameter. If successful, the innovation could provide an alternative means to current commercial excavation technologies.
Inspiration for the robot comes from the soft robotics doctoral research of project leader Dr Deepak Trivedi, formerly of Penn State University. “Earthworms rely on a muscular structure filled with fluid, called a hydrostatic skeleton,” explained Dr Trivedi. “When they move, some sections of their structure radially expand to enlarge the tunnel while anchoring the worm, while others become longer to create movement and penetrate further into the soil.”
Dr Trivedi continued: “We have designed a prototype that is several feet long, with hydraulic artificial muscles that mimics the agility of earthworms moving through soil and with the force of tree roots penetrating through soft rock.”
The soft robot is claimed to be able to adaptively change its gait depending on soil conditions and create tunnels without the need to bring material to the surface, giving it benefits of efficiency and stealth. The Colorado School of Mines and Sandia National Laboratories have also provided input into the programme.
