I built this today, it is a pretty sturdy robot that is able to climb to another floor as well as descend from above.
I am going to see if i can improve on this robot later as it should be able to climb high obstacles so long as the string is secured tightly.
I have a grappling hook on this but it has to be manually attached with your hands, i want to make it so that you can attach it from the controller.
The whole unit functions great, it climbs slower than it descends but through some miracle 2 motors were able to lift this robot vertically without any problems.
A video of this will be finished soon and i will post the youtube link.
I had tried to make a shooting mechanism but if failed because it only shot the hook 5ft.
If i want to make a real grapple gun i am going to have to have an air powerd potato gun with a solenoid valve and a small air tank that can lob a hook a good 25ft+.
I just think that this is an interesting robot and ultimately i want it to be a giant spy bot capable of climbing.
The mechanism that climbs is simple, it is two motors and 2 standoff beams that spin which retract the string.
It does spin a little when you let the cable down and i am working on that, i plan on have 2 strings on 2 separate motors that retract so that it wont swing side to side.