Biped Ankle with SES

Hi,
I’ve been wondering what the best way to make an ankle as close to the ground as possible is.
I came up with a similar look to the scout. It is a bit different though.
Has anyone tried anything like this? I thought I’d post this idea for anyone to use if they wanted. The ankle gets heaps of movement in all directions. The direction it is most limited in is bending backwards, but I found it gets to 40 degrees from horizontal which is pretty good. I don’t know how far the scout one goes forward, but I don’t think it would be that far.

Anyway, let me know what you think… Any changes or anything, whatever.

img2.putfile.com/thumb/8/23501550594.jpg img2.putfile.com/thumb/8/23501550563.jpg img2.putfile.com/thumb/8/23501550558.jpg img2.putfile.com/thumb/8/23501550588.jpg
(Click pictures for full size)

That does get the ankle joint closer to the foot center. I guess you would move the dual servo bracket to the upper leg then if you are using a reverse knee.

what are you trying to design here? a forward or backward knee?

from what i pick up, this seems like a great design to make a forward knee, which would be great for robo-one like stability.

if you want the ankle as close to the ground, why use the 15 degree brackets? that picks it up even more than a regular one.

I was thinking of this for a forward knee. I did use the 15 degree bracket for the bottom one, as the square one was too close to the ground for it to turn with the other servo bracket on it.

I’m not actually building one of these, but I was wondering how best to do it, and thought someone else might benefit from it if they wanted to.

Whats funny is I’ve been doing the same thing for a long time. It’s a pretty tough challenge to overcome. You know, having the ankle bend left and right while allowing the ankle to bend up and down as well (which is what you accomplished here).

However, I was trying to do it without the 15 degree. Using the square multipurpose bracket to mount a servo onto the foot allows for very little turning of the ankle up/down servo attached (you actually picked it higher with the 15 degree, so now you can turn a lot more).

What i did, I tried to literally lift the square bracket, using one of those circular hubs (seen below). However, it just seems like ruined the balance of the robot, as if once a lot of weight is put on the foot the ankle would come crashing.

Here are your ankles on my new bot. Just put it together a few moments ago. I’ll let you know how they work when I start programming.

~Mike

http://img484.imageshack.us/img484/3774/sh101702sj6.jpg

That looks great. Would love to see some videos of it walking when you get that far.
Hope it all works out alright.