“We must dominate underground,” says the commander of a Ukrainian robot-warfare battalion. His unit, the ground-robotics battalion of the Khartiia Corps’ Lava drone regiment, is developing unmanned ground robots adapted to fight specifically inside gas pipes and narrow confines, for the 15-kilometer advance Khartiia drove through them on the Kupiansk front in Operation Veles, the corps reports.

Underground is the drone war’s newest front. Russia spent the past year crawling through gas pipelines to slip behind Ukrainian lines. Kyiv command answered by going underground itself in Veles. Now both sides are reaching into a domain that the commander, with the callsign Matematyk, calls harder to fight in than the air or the surface.

Robots built for the pipe

Matematyk’s team is reworking its ground robots, once surface machines, for the cramped confines of a pipe and the particular tasks of the new domain, Khartiia says.

There is a very large list of works that must be carried out to fight underground and counter the Russian underground. This is a new class of technologies and problems that we have to confront, he explains.

"Because underground movement, or any actions underground, are in fact very complex, far more complex than air or ground operations,” Matematyk shares.

A domain with lessons from the last century

The technology that exists for working below ground, he says, is built for the heavy machines that serious companies use to dig metros, not for war, yet the fighting has already moved underground and will only spread. The question is how fast Ukraine can adapt, according to Matematyk.

“From the example of the First World War and the various underground battles in Europe, we can understand how dangerous and how complex this is. So the only conclusion for us is to work with robots that can, at the least, increase our effectiveness and replace people in carrying out this work underground,” Matematyk adds.

Ukraine is already pushing robots into its most dangerous jobs above ground, in one recent assault sending 28 armed machines and no soldiers at Russian lines, as it strains to spare a manpower-short infantry.