anthropy, https://www.youtube.com/watch?v=1KEtxTQUzxY
you might've heard of disney's 360 treadmill project, but do you know how it works? This video is a nice demo
Apparently it's made up out of little cones that can tilt in any direction, with little rotating disks on top. By tilting the cones such that only one side of the disk touches a surface that's on the grid, and rotating the disks, you can move anything in any direction on the grid of cones.