The Legged Squad Support System (LS3), the semiautonomous quadruped robot developed by DARPA and Boston Dynamics that can carry 400 pounds (180kg) over rough terrain, is very nearly ready for prime time. LS3 (aka AlphaDog) can now listen to voice commands, follow the (human) leader, and self-right itself after falling over.

When we last saw DARPA’s LS3 back in February, it had just taken its first steps in the wild. This was a major step forward, as previous iterations of AlphaDog had been tethered to external hydraulics — not so useful, for a warfighting mule. Since then, LS3 has been outfitted with a curved chassis that allows it to roll over (this is demonstrated beautifully in the video below), and updated software.

The updated software allows LS3 to follow the leader, improves maneuverability in urban environments, and improves foot placement when traversing rough terrain. All of these features are present in the video (you really ought to watch it). About two minutes into the video you also get a glimpse of LS3’s environmental perception, and how it navigates around obstacles while still tracking the (bald) leader.

One thing that isn’t clear is the engine sound: In the first field test video (embedded below), LS3 is incredibly noisy — so noisy that you probably wouldn’t want to use it in combat. In this new video, the engine sounds a lot more muted — but to my ears, it sounds more like DARPA has post-processed the video to make the engine sound quieter/less bassy.

Moving forward, a lot of testing and development remains to be done. The original plan was to finish testing by the end of 2013, followed by a real-world deployment with the US Marines in 2014, but it now seems that testing will continue into the first half of 2014. Before it can be deployed, DARPA/Boston Dynamics must show that LS3 can carry 400lbs 20 miles in a 24-hour window, without being refueled. The eventual goal is for each marine squad to have one or two LS3s carrying their gear (marines carry up to 100lbs (45kg) of gear), providing a mobile power source, and perhaps even acting as a steed for wounded (or lazy) soldiers.

Finally, as an added bonus, here’s an early video of Boston Dynamics’ BigDog, the predecessor to AlphaDog.

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