Just last week, the Pentagon’s research division — DARPA — set a new speed record with its four-legged running robot Cheetah. Now it is testing out another one of its robots on four legs — this one designed not for speed, but for carrying gear.

DARPA’s AlphaDog by Boston Dynamics (also known as prototype LS3 — Legged Squad Support Systems) had been previously tested outdoors, but this trial, according to DARPA’s release, demonstrates not only greater mobility but more stealthy sound control and “follow the leader” capabilities.

DARPAs LS3 Prototype Demonstrates Sensors to Follow Commands and Quieter Design

LS3 climbs uphill. (Image: YouTube screenshot)

The ultimate goal of LS3 is to act as a “pack mule” robot that can “unburden dismounted squad members by carrying their gear, autonomously following them through rugged terrain, and interpreting verbal and visual commands.”

According to its description in its latest demonstration video, LS3 can carry up to 400 pounds, travel 20 miles without refueling and follows humans using a sensor system. Watch the robot demonstrate this ability over a variety of terrain:

“We’ve refined the LS3 platform and have begun field testing against requirements of the Marine Corps,” Army Lt. Col. Joe Hitt, DARPA program manager, said in a statement. “The vision for LS3 is to combine the capabilities of a pack mule with the intelligence of a trained animal.”

Hitt also said the technology is now 10 times quieter, which will allow soldiers to have a conversation while still walking near it.

“Other improvements include the ability to go from a 1- to 3-mph walk and trot over rough, rocky terrain, easily transition to a 5-mph jog and, eventually, a 7-mph run over flat surfaces, showing the versatility needed to accompany dismounted units in various terrains,” Hitt said. “The LS3 has demonstrated it is very stable on its legs, but if it should tip over for some reason, it can automatically right itself, stand up and carry on. LS3 also has the ability to follow a human leader and track members of a squad in forested terrain and high brush.”