ankle design

i've done a couple of iterations on ankle designs. the problem with an ankle joint is that it is difficult to get your rotation axis' near the ground. if you look at peoples robocup designs they are all pretty much the same. two joints in series. besides not having your 2 rotation axis' not intersecting at a point, your robot basically ends up on stilts. i don't want to do that.

the first design was a brute-force style design. it was just too bulky.

IMG BILLY PUT IN YOUR STUPID PICTURE /IMG

the second design was a swashplate-like design.

IMG BILLY PUT IN YOUR OTHER STUPID PICTURE /IMG

i actually like the swashplate design, but after thinking about it for awhile i realized that i could just get rid of the swashplate all together and have the pivot become virtual. the concept is simple enough, just a bunch of parallel arms.

this prototype is oversized. the foot was random a piece of wood i had laying around that is tied on with just wire. mouting the foot properly requires some more parts that i don't have right now. even so, it works pretty damn well. it is very mechanically solid and i'm quite happy with it. the final design will have a 3rd axis to allow for foot twist. i think i'll be able to mount a servo right in the virtual space which is pretty cool.

http://z425.com/photos/ankle02.asf