When I spotted it today around the corner form my house, I was surprised to say the least.
With standing headroom inside and high ground clearance, the rig was supposed to be as self-sustaining as possible, and able to go anywhere a four wheeled vehicle could go. From what I have been able to find on the internet, they seem to have been able to do this despite several incidents.
The web site I have found seems to be out of date, but is well worth a visit.
If I learn more I will update.