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\u201cWe use the subterranean environment because it is so complex and challenging it can really serve as a compelling forcing function to achieve breakthroughs in technology areas,\u201d said Timothy Chung, a program manager in DARPA\u2019s Tactical Technology Office. With those breakthroughs, \u201cwe can also do a better job in other complex environments, such as urban environments or potentially even underwater.\u201d<\/p>\n\n\n\n
Chung oversees DARPA\u2019s Subterranean Challenge, a project designed to find new ways for the military to map, navigate and search a range of underground environments. This includes caves, tunnels and underground spaces in cities. Designing robots that can go underground, look for objects and report that information back would let the military operate below the surface with far more finesse and ability than it can do so today.<\/p>\n\n\n\n
\u201cThe recent drop of the [Massive Ordnance Air Blast] bomb in Afghanistan\u2019s Achin district was on a cave complex because we don\u2019t want to deal with these environments,\u201d Spencer said. \u201cWe view them as obstacles: don\u2019t go down there unless you have to and, if you do have to, we treat it as a kind of a clearing operation \u2014 you\u2019re going to go down there to get the bad guy.\u201d<\/p>\n\n\n\n
But caves, tunnels and underground spaces are a difficult place to navigate for humans. Robots can be deployed without risk to the searcher; however, ensuring the military\u2019s technology works in subterranean spots is a struggle.<\/p>\n\n\n\n
\u201cOne of the cases here is recognizing how much an environment, especially challenging environments, are impediments for concepts like autonomy and perception and robotic mobility and networking,\u201d Chung said. \u201cThese spaces continue to be thorns in the sides of technologists.\u201d<\/p>\n\n\n\n
In the same way that cellphone or GPS signals get lost in canyons or remote stretches of mountains, caves are what\u2019s half-jokingly referred to as a \u201cpassively denied environment.\u201d <\/p>\n\n\n\n
Traditional signals, designed to travel through open air and across empty swaths of land, or up to satellites and back to Earth, struggle to penetrate the underground. If there is a singular use case driving the development of autonomous tools in the military, it\u2019s the need to have those machines or vehicles or sensors work where remote control is near impossible.<\/p>\n\n\n\n
\u201cThe underground environment turns out to be quite a different animal than driving outside,\u201d said Frantisek Brabec, a solutions architect for Robotika International. The Prague-based company fielded a robot in a DARPA integration exercise. \u201cYou cannot use GPS; the compass doesn\u2019t really work either because there\u2019s lots of mining equipment, lots of iron. All you are left with is just a few tools that you would normally have available, and communication with the robot is difficult.\u201d<\/p>\n\n\n\n
In future battlefields, as well as many today, adversaries could jam parts of the electromagnetic spectrum. In caves, remote control is likely impossible. If a robot is going to go spelunking, it will need to spelunk on its own.<\/p>\n\n\n\n
\u201cIn the rules, we articulate that tele-operation is not prohibited,\u201d Chung said. \u201cBut, frankly, the environments will severely challenge current approaches to tele-operation.\u201d<\/p>\n\n\n\n
DARPA\u2019s contest to solve these problems launched in January 2018 with a proposer\u2019s day. In April, seven agency-sponsored teams, as well as two self-funded teams made their way to Idaho Springs, Colorado, for an integration exercise held at the Colorado School of Mines\u2019 Edgar Experimental Mine. <\/p>\n\n\n\n
The experimental site has nearly two miles of pathways, with dead ends, interconnected passages, slopes and shafts. The abundance of caves in the United States means DARPA can host a launch event in one, an exercise in another and then a competition in a different cave, so that teams are exploring a new system every time.<\/p>\n\n\n\n
A major component of the exercise was determining how well the teams\u2019 robots could locate artifacts, such as cellphones or tools, placed in the site. The organizers even hid \u201cthermal manikins,\u201d which showed up on infrared cameras, to represent survivors or other people that might be encountered underground.<\/p>\n\n\n\n
\u201cWith our robot, the camera is looking around and it doesn\u2019t make a final determination on whether something is an artifact or not, but it highlights certain potential hits and then when the robot comes back, the human operator validates the sights and reports,\u201d Brabec said. \u201cWe had a laser scanning horizontal and on an angle and we measured the way the wheels turn to calculate position.\u201d<\/p>\n\n\n\n What DARPA is ultimately looking for isn\u2019t so much a single platform that can master a specific cave. Instead, DARPA wants industry thinking about a range of platforms that can work across any kind of underground.<\/p>\n\n\n\n One such diversified approach is the \u201cmarsupial solution,\u201d where one robot carries other robots on its back (think: smaller quadcopters). Using a main body for endurance with a smaller body for flight and aerial mapping combines the better attributes of two kinds of transportation, but it also requires figuring out how to navigate a cave by air and by ground, and how to get the robots to link back up and then report out meaningful information.<\/p>\n\n\n\n Neither of these are easy problems.<\/p>\n\n\n\n \u201cWe are interested in technologies that can deliver what we call actionable situational intelligence in underground environments, not just the delivery of a map, whether 2D or 3D,\u201d Chung said. \u201cWhat I want is what the operational side is interested in learning. They\u2019re interested in where survivors are located. They\u2019re interested in the quality of air; do I need special equipment before I can maneuver into these spaces? Are there hazards they should be aware of, in addition to all the twists and turns of these environments?\u201d<\/p>\n\n\n\n The Colorado mine allowed teams to explore challenges in a novel environment for the first time, but the true competition comes in August, with a tunnel circuit at the National Institute for Occupational Safety and Health (NIOSH) mine in Pittsburgh. <\/p>\n\n\n\n Subsequent tests in urban and cave environments will come in February and August 2020, respectively, with a final event in August 2021. The locations are withheld until a formal announcement to avoid the possibility that teams over-fit their solutions and designs for a specific environment, rather than creating a versatile tool that can be thrust into the unknown.<\/p>\n\n\n\n \u201cThere\u2019s going to be underground in all the cities that have over 1 million people,\u201d Spencer said. \u201cThey\u2019re going to the underground infrastructure of sewer systems, telecommunication systems, subway systems. That literally is another level of a map that we don\u2019t even think about. DARPA is pushing us to the simplest capabilities that we need to operate underground.\u201d<\/p>\n\n\n\n Besides the physical events, DARPA is also hosting a parallel virtual challenge, where teams can enter and compete with robots in a simulated environment. Using the kind of modeling one might find in a video game, the virtual machines will navigate hazards \u2014 like sudden drop-offs or dense, dusty air \u2014 while looking for the same kinds of artifacts strewn through the site.<\/p>\n\n\n\n \u201cWe can take everything from models of the existing caves or environmental simulations and have robots experience real world environments just rendered in a virtual context,\u201d Chung said. \u201cWe\u2019ve also gone to lengths trying to provide a representative of models for radio frequency propagation in these underground environments. How that comms link works or how the millimeter-wave radar for imaging interacts with the environment \u2014 for better or for worse, typically I\u2019d say for worse \u2014 to provide an additional level of realism for the virtual competitors to face with their solutions.\u201d<\/p>\n\n\n\n Besides the future needs of soldiers and Marines who might fight their way through underground environments, the competition also considers the interests of the first responder community.<\/p>\n\n\n\n \u201cConducting rescue operations in subterranean environments presents challenges that are sometimes different from those of any rescue operations above ground,\u201d notes the Army\u2019s Small Unit Training in Subterranean Environments. Saving lives in caves requires many of the same tools and skills as successfully clearing caves from hostile forces, with a different set of options for what to do when people are encountered.<\/p>\n\n\n\n \u201cWe are interested in what we can learn when the underground environment is unknown,\u201d Chung said. \u201cWe don\u2019t know what the dangers are that lie within. So how can we exercise our technologies in those kinds of operational considerations?\u201d<\/p>\n\n\n\n A half-century after the Army wrote off caves and tunnels in war as primarily targets worth detonating, DARPA is challenging industry to find a way to navigate through that unknown. If there is a path that can make underground warfare safer for humans, it is one that will be trail-blazed by robots. <\/p>\n","protected":false},"excerpt":{"rendered":" If caves are the next battlefield, the United States must develop the mechanics to win in them.<\/p>\n","protected":false},"author":7,"featured_media":56192,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_yoast_wpseo_meta-robots-noindex":"","_yoast_wpseo_meta-robots-nofollow":"","_yoast_wpseo_canonical":"","_acf":"","_yoast_wpseo_primary_category":21,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","_smg_distribution_targets":[]},"categories":[7,106,29,32,21],"tags":[],"coauthors":[3021],"class_list":["post-19187","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-battlefield-tech","category-daily-brief","category-home","category-newsletters","category-unmanned"],"acf":{"subheadline":"","legacy_arc_id":"DB3R4XH2QZGC7CP6CFT5QQJM5M","arc_canonical_url":"\/unmanned\/2019\/06\/03\/how-the-military-could-find-robots-it-needs-to-win-underground\/","remove_feature_photo":false,"is_sponsored":false,"subtype":"","redirect_url":"","disable_inline_ads":false,"native_logo_pretext":"Presented By:"},"yoast_head":"\n![\"\"](\"\/wp-content\/uploads\/2026\/08\/Cover_2.jpg_cb2d41.jpg\")
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