The U.S. Army Is Exploring Mechanical Third Arms and Exoskeletons for Soldiers

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We’re still a long way from a Metroid-style space bounty hunter suit, but the U.S. military is prototyping new wearables to enhance soldiers’ combat abilities. These include an exoskeleton similar to those being trialled for factory workers, and a prosthetic arm device, officially named the “Third Arm,” meant to make heavy machinery feel weightless.

The Army Times reported this week that soldiers will soon test the ONYX exoskeleton, designed to take the load off of a wearer’s hips and knees, increasing their stamina. The 10th Mountain Division will be the first American military unit to evaluate the devices later this year, working with researchers who will attempt to improve the exoskeleton’s fit, make it quieter and faster, and finally test it for “ruggedized operation.” During the R&D stages, prototypes were tested in labs while wearers exercised on a treadmill. The real test will be how the ONYX responds to water damage, and uneven, mountainous environments.


The cool practicality of the exoskeleton is contrasted with this completely bonkers-looking third arm prototype. The U.S. Army Research Laboratory hopes the device will make heavy weapons feel significantly lighter, taking pressure of each soldier’s arms and shoulders. While the exoskeleton is being tested for eventual field usage, the Third Arm is considered more of a concept than a potential new addition to military equipment.

“What we have right now is a very specific device, but we can learn from that device,” said Dan Baechle, a mechanical engineer working on the project. “I hope in the future what we’ll end up with is something that will help the Soldier. Whether or not it’s in the form you see today, that’s less important.”

While the third arm is unlikely to get a full rollout anytime soon, the exoskeleton will continue being tested into 2019. Not quite the cyborg super soldiers we’ve come to expect from Metroid or Halo, but increasing stamina can be crucial differences in high pressure environments.