Legged Squad Support System

The Legged Squad Support System (LS3) was a DARPA project for a legged robot which could function autonomously as a packhorse for a squad of soldiers or marines. Like BigDog, its quadruped predecessor, the LS3 was ruggedized for military use, with the ability to operate in hot, cold, wet, and dirty environments.

Source: Wikipedia — Legged Squad Support System (CC BY-SA 4.0)