I am just interested in how to build a wall bot. I will probably never build one but I am just curious.
use a scissor mechanism that expands horizontally to the distance you want to block.
just look at videos/threads about wallbots and you will get an idea. There is no one way to build a wallbot as many different designs could prove very effective.
This thread has a lot of stuff in it
That should be enough to get you started XD