Bristlebots

[Remote-Controlled Dave]

Do bristlebots qualify for a walker weight advantage? I know they were classed as walkers on Techno Games, and they convert rotary motion to linear...thought about giving one a go for a while.

[Rapidrory]

Smidge was originally gonna be a bristle bot, but it was very unreliable so I changed it. I'd also thought about doing a larger one, like with a boot brush or something, but never got around to that.
Seeing as the definition of a walker is:

A robot whose final drive output rotates through less than 180 degrees

I'd say they qualify as a walker...

[Remote-Controlled Dave]

Me too, but I wanted to worm out objectors before investing the time into one. There's some great ones in the States.

[Hogi]

how does a bristlebot move?

[peterwaller]

I agree with Rory the final drive output must be the bristles and they don't rotate so it must be a walker / shuffle.
It would be interesting to see if with some form of variable drag on either side you could devise some sort of directional control.

[Shakey]

Maybe 2 bristles together with speed controlled motors on each? Damp the connection between them.

[Rapidrory]

Maybe 2 bristles together with speed controlled motors on each? Damp the connection between them.

That's how I was gonna do smidge, just couldn't find small enough bristles... a couple of toothbrush heads might work well for an ant though.

[Remote-Controlled Dave]

Dan, a bristlebot has a motor up in the air with an offset weight so when it rotates it causes a vibration. The robot then has bristles on the bottom and the vibration causes the robot to bounce on the bristles that creates movement. Its how the original Hexbugs work, the ones that run round the tracks, though in an any you'd need to make some degree of control so it can drive and turn.

[razerdave]

How Cyber Snail ( a bristlebot) worked:
http://www.bbc.co.uk/science/robots/techlab/sub8.shtml

[Hogi]

oh i see. yeah i should think that would qualify as a walker as the bristles wouldn't actually rotate at all. it couldn't be a shufflebot by our deffinitions though as the bristles would not have a recovery phase. it's a very clever idea. if you used two 30:1 gear motors you might get up enough speed for a decent vibration. invert the direction of one motor and create vibration in the opposite direction on one side and the robot should turn. that's my theory anyway.