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chip updates: making part of the leg [updates]

So we're still waiting for a fewww of the parts to come in to finish the knee joint but in the meantime we have made some of it:

We started ofc with the lovely water jet...

Add some sandblasting finish to get the parts looking nice...

Then we started assembling w/ the hardware that we had - still need to order the steel drive cable and other things and also 3D print the capstan reducer, but those will come when the parts come. Oh and a foot too which we have to design.

Right now we've been looking into design for the hip and the ab-ad joint. We have a few ideas now from Yong-Jae Kim's paper on AMBIDEX.

The below is a combination of a design of ambidex from this video:

And the unitree actuator from this video:

Now what we want to do essentially, is put this into CAD and see if it'll work with our system. Will need some modification over the original, we also probably want to make a prototype as well but we'll get there.

The challenge here will be designing the system for the water jet rather than professional manufacturing or CNC'ing. But if we realize that the HASS may provide a significant advantage we may do that. (in fact it would be good practice.

The biggest problem with this design would be the fact that to achieve a gear ratio of 20, the pulley size ratios must also be like 20. That's kind of nuts so maybe we can combine this with the previous idea.

So something like this would allow us to keep the system compact but also provide us with the 20:1 ratio we've been hoping for. Let's put this thing into CAD!

Well actually... maybe we need to figure out how a mechanism like this would be held together, we'd need to do some interesting things.

The above is an initial mechanism idea for the bearing system for the shoulder and ab-ad joints. We have a needle roller bearing that's bolted to the structure w/ M16 bolts. We just need to figure out how to design around this.

ok... we are confused so we will do the rest later

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