Modern autonomous machines are a fusion of technologies. Some are simple, like tracked bodies. Others are more modern, like those that use artificial intelligence for object-identification and those that cross-reference visual confirmation with electro-optical and infrared lenses against radar signatures.

The connective tissue between, of digital camera lenses and commands relayed between human and machine by radio signal, is a mixture of complexity. The parts separately are routine, everyday features of modern weapons development. The composite form, together, feels almost revolutionary.

All of this is to say: A Norwegian defense firm put a U.S.-made missile on an Estonian-made ground robot, and then fired that missile. It is at once an iteration and a new form.

Earlier this month, Norwegian defense giant Kongsberg announced it had mounted and demonstrated a remote weapon launcher on the THeMIS, an Estonian-made ground robot. The missile fired was a Javelin anti-tank missile made by Raytheon and Lockheed Martin, and the test took place in Alabama.

Javelin missiles are already part of the gear available to soldiers. As Defense News notes, the most immediate application of this technology is taking equipment off the backs of human soldiers and putting it onto a robot that can carry it along and follow it into combat. The Army is exploring several robots for the logistical part of this burden sharing. What the THeMIS unmanned ground vehicle brings, in combination with the Kongsberg PROTECTOR remote weapon station, is not just carrying a weapon but the potential to fire it.

So what, exactly, does mounting a weapon on a robot bring to the battlefield?

“Kongsberg believes that this could be a valuable tool in situations where you want to conceal, hide or not expose the host platform and soldiers,” the company said through a spokesperson. “The UGV with a PROTECTOR weapon systems gives the Commander the opportunity to maneuver and place the sensors and effectors in desired and possibly hard-to-access locations without risking lives of troops and costly manned platforms.”

The simplest case for the armed robot is that it functions as an extension of the human, bringing greater reach without exposing humans to the same risk. Add more information from other sensors, and the armed robot becomes a useful weapons platform drawing on targeting information from the whole of the battlefield, not just its own sensors. It would gain direction by its human operator.

One of the major hurdles in converting a robotic platform from a tool that is used by a human to an independent agent overseen by a human is autonomy. At present, unmanned vehicles largely follow the remote pilot model, with a human spending time and energy managing the machine and watching its operation closely. The more of that process is automated, the more a human can simply check in on how the machine is performing, and take action that explicitly requires human direction. Say, an order to fire a weapon.

“To be able to realize the full potential of these sort of systems autonomous aids for area scanning, advanced tracking systems and autonomous target recognition needs to be available,” said Kongsberg.

The company emphasized that it is prepared to provide these autonomous tracking and targeting features as part of a “next generation toolkit,” and noted that the loop of sensor-computer-human is designed so that ”the system is not vulnerable to electronic warfare or hacking.”

An ability to operate in the face of electronic warfare that would render remote piloting impossible is one of the driving forces of autonomous machines in warfare. While it is likely impossible to make a system that is invulnerable to hacking or electronic warfare, it is much better to have designers aware of the risk than designing without it in mind.

“All engagements are strictly human in the loop. Without going into details, all other operations can be assisted in some way,” said Kongsberg. “At this point it is also very important that operating the weapon system on a UGV shall and can be done in the same manner as a manned platform weapon system.”

As for functioning as a remotely piloted system, Kongsberg pointed to the PROTECTOR’s long history of use as a remote station on fixed points. When mounted on a vehicle, the sensors and processing of the weapon system can sometimes be used to help the human operator navigate.

“The whole engagement and launch sequence is done by the operator from the same control group,” said Kongsberg, “Hence the same sensors are used for targeting, and the operator easily and quickly switches between the weapon systems on his control group.”

At present, both technological limitations and expressed desires of military customers are putting autonomous features in battlefield robots as tools that help human control, rather than deviations that supplant it.

What remains to be seen, as robots like THeMIS armed with weapons like Javelin roll onto the battlefield, is how long commanders and operators will want to subordinate those autonomous functions to human controllers. The technological barrier to full targeting and firing autonomy is present but minimal. As that barrier erodes, it will be up to normative and doctrinal standards, as well as international law, to see if an emphasis on human-in-the-loop control holds.

Kelsey Atherton blogs about military technology for C4ISRNET, Fifth Domain, Defense News, and Military Times. He previously wrote for Popular Science, and also created, solicited, and edited content for a group blog on political science fiction and international security.

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