It looks like a bull, trots at the speed of a wolf and carries equipment like a pack mule, but does it have a place on the battlefield of the future? Researchers in the US are conducting a two-year study of a robot that promises to lighten the load that soldiers must carry and they gave it a high-profile demonstration in September.
The four-legged robot, developed by the US government-funded Defense Advanced Research Projects Agency (DARPA) and Boston Dynamics, is part of DARPA's Legged Squad Support System (LS3) programme, and is packed with technology. It's a development on Big Dog, a robot platform developed by Boston Dynamics several years ago.
As warfare gets more high-tech, soldiers are being asked to carry more gear - as much as 45kg, according to the US military - and that can slow them down, bring on injuries or hasten the onset of fatigue. So the US Army and DARPA have made physical overburden an important focus of their technology research.
The new robot walks on four legs and has a fast-reacting balance system that means it won't fall over if shoved from one side - something that most robots can't handle. If it does somehow fall, it's capable of righting itself. There are also "eyes" at the front, actually electronic sensors that constantly scan the surroundings.
A two-year test of the robot began in July and, if all goes well, will culminate with models of the robot taking part in a battlefield exercise alongside soldiers.
Before that happens, researchers want to perfect three distinct autonomous modes: "leader-follower tight" in which the LS3 follows as close as possible to the path of a human leader; "leader-follower corridor" in which the robot follows a leader but has the ability to decide its own path; and "go-to-waypoint" where it makes its own way to a GPS coordinate using sensors to avoid obstacles.
The robot is powered by a petrol engine, which brings advantages - plans call for it to be able to carry 180kg on a 30+ kilometre hike over 24 hours - but also means its noisy. Early prototypes were so loud it wasn't possible to have a conversation nearby but that is slowly changing. The latest version, demonstrated a few weeks ago, makes a 10th of the noise.
The demonstration, at Joint Base Myer-Henderson Hall in Virginia, gave General James Amos, commandant of the US Marine Corps., and Arati Prabhakar, director of DARPA, a close-up look at the robot.
"For me, to see where it's gone just in the last four years and where it was with Big Dog, which was fascinating, you had to have a leap of imagination to know that we would get there eventually. We're getting close. Very, very close," Amos said, according to a story about the demonstration on the US Army website.
During the test it was controlled with the Tactical Robot Controller (TRC), a handheld touchscreen controller that can operate many of the robotic platforms used by the US military including the TALON, Dragon Runner, Robotic Bobcat, Raider and MAARS robots.
In the future, developers want to add voice-recognition to the robot so soldiers will be able to command it to do things by voice alone, DARPA said.
And in addition to hauling equipment, the generator in the robot can also be used to recharge of power equipment when needed.
Tests of the robot are scheduled to take place approximately every quarter between now and the end of the research program. In December this year it will take part in its first test with the Marine Corps Warfighting Laboratory (MCWL) at a US base location yet to be disclosed.