This bot climbs a pole - slowly.
Note: just discovered this bot will also climb 1/4 inch round electrical cable.
Why did I make this bot?: I saw a cool video showing a bot climbing up a person's pant leg which then led me to wanting a rope climbing bot but my first effort bot didn't have enough torque to climb a rope. Then as I was tearing apart a toy I found a nice geared motor and thought, "how can I use this to build a rope or pole climbing bot?" This bot is the result.
I wanted to keep it simple, no servos, computers, etc. And just use junk found around the house.
How does it work?: it uses a rope climbing device called an "ascender" to clamp the pole. This bot has two ascenders and a motor to rotate a shaft to push the top part of the bot up and pull the bottom part of the bot up. The sequence is:
- when motor shaft is rotating up: clamp the pole on the bottom part of bot and push top part up the pole
- when motor shaft is rotating down: clamp the pole on the top part of the bot and pull the bottom part up the pole
My grippers or "ascenders" use laminated epp foam to grip the pole. I think semi-hard rubber would work better but I didn't have any around. The gripper must not be too hard or it will slip against the pole and not hold. It must not be too soft or it won't slide against the pole when it needs to. It must be just right.
Photo 1: a close up of the bot.
Photo 2: shows a schematic of the bot and how it works. I think if anyone wants to make one they can understand the idea pretty easily and most probably build a much better one than mine. Good luck.
Photo 3: close up of motor gearbox and arm.
Photo 4: detailed photo of top part of bot (part A).
Photo 5: detailed photo of bottom part of bot (part B).
How to improve this bot: I think this bot can easily be adapted to climbing a rope by simply joining the top part of the bot with the bottom part using two tubes - one sliding inside the other. This would take care of the wasted motion between the two parts of the bot and also keep the rope straight between the two parts. I might try that next, or I might go off and do something else - probably something else.
Bot Philosophy (optional reading): As I pondered this particular bot it occurred to me that I could have called it:
- the Bachelor (or Bachelorette) bot as the top bot is always running away from bottom bot.
- the Great Man Bot - behind every great man there is a woman pushing him on.
- the Sisyphus Bot which is doomed to endlessly climb the pole of life until its battery dies. One must imagine the bot is still happy.
Warning: this bot only goes up.