The wheel is round. So it seems, guys. This is a fact of life for strollers, trolleys, vehicles and most of the ancient and modern means of land transportation. One wheel is just round, come on. That is: IT WAS.
In a collaborative effort between Carnegie Mellon and the Defense Advanced Research Projects Agency (DARPA), a configurable “transformer” wheel was created. The RWT (this is its name) can transform a wheel into a sled, or a track, while a vehicle is still moving.
With the push of a button and a few seconds, military vehicles are able to adapt to any terrain.
The RWT initiative is part of the Ground X-Vehicle Technologies program managed by the Pentagon.
Other goals of the program, according to DARPA's website, include reducing vehicle size and weight and increasing vehicle speed in "today's armored fighting vehicles." These are generally very specialized and different vehicles, used in desert or mountainous regions: a configurable transformer wheel can make them more homogeneous, or even unify them, to reduce production and logistics costs.

From the presentation, I infer that RWT aims to provide vehicles with the “ability to traverse various off-road terrain, including slopes. Capabilities include revolutionary wheel/track and suspension technology that enable greater terrain access and faster travel both on and off-road compared to existing ground vehicles.”
Carnegie Mellon announced in November last year that the RWT was one of the winners of Popular Science's “Best of What's New” award. Dimi Apostolopoulos, a scientist at Carnegie Mellon University's Robotics Institute, said in a statement: “Creating a reconfigurable transformer wheel system that works on a moving vehicle at high speed was an exceptional challenge, but our NREC team devised a project that works and has the potential to transform mobility on the ground. ”
Last April 19 this video showing a first test of the RWT was published on YouTube. This is a demonstration only on an asphalt road and not on other terrains, but it gives the idea perfectly. Since then other refinements have increased the range of use of the configurable transformer wheel, and new tests will soon be shown on less fluid terrain before RWT is implemented on operational military vehicles. Vehicles of the future that at this point are not just announced with their own intelligencebut also virtually unstoppable.
In addition to the configurable transformer wheel, other creations of the GXV-T program include technologies such as Multimodal extreme travel suspension, or METS. Having good suspension is critical when traversing abnormal terrain, and METS gives the vehicle the ability to raise the wheels 30 inches or drop 42 inches. Each wheel can also be controlled separately, and this, combined with the RWT, makes it almost impossible to get stuck.

All feeds of the configurable transformer wheel are available on the DARPA website.