

What makes the ankle exo so effective is its simplicity - rilut
http://www.popularmechanics.com/science/health/a14923/ankle-exo-leg-wearable-tech/

======
wherkewitz
Fucking. Sweet. I actually wrote this story!!

~~~
wherkewitz
Also: Everyone should know this. There are still huge issues that need to be
figured out before this becomes a commercial product. The 7% figure is bound
to change depending on the speed you walk at (diff. speeds will likely require
springs with diff. stiffnesses for optimal efficiency). Both Steve and Greg
talked about future incarnations that could switch between multiple springs.

...and I didn't write that headline, or the dek (the thing under the head)

~~~
maxerickson
Did you get a sense of whether it required tuning to the user? It seems like
the ratchet disengaging at the right moment would be quite important to making
it comfortable to use.

~~~
araes
To do this in full production mode, I would think you would probably make it
user tunable.

As the article says, most of it is fairly simple. Just a spring for a cable
and a ratchet that moves with the motion of your foot (kind of auto tuned),
and grabs the spring.

If the spring was remotely tensible, you could probably just walk and adjust
it until it felt best.

You could probably also do that at various speeds and then create a smooth
mapping of ensuing parameters for various gaits.

~~~
maxerickson
Yes, I think it has to either be tunable or self adjusting. If the ratchet
releases early, you are just carrying it around. If the ratchet releases late,
I expect it will result in uncomfortable tugging.

So my question is more about the behavior of the implementation, not about the
design space for it.

------
shanemhansen
My grandfather was an engineer who suffered from a degenerative muscle
disease. This exo bears a resemblance to the brace he wore to hike around the
southwestern desert.

------
csours
CMU Robotics talk on this exo. Includes facts, figures and a lively discussion
(75 minutes).:
[https://www.youtube.com/watch?v=j58ZP7vwcsU](https://www.youtube.com/watch?v=j58ZP7vwcsU)

------
rilut
Here's the link for the paper:

Nature: Reducing the energy cost of human walking using an unpowered
exoskeleton
[http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...](http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14288.html)

------
pat2man
I wonder how this compares to trekking poles.

~~~
wherkewitz
Trekking poles increase your _overall_ metabolic exertion, but make walking
feel easier because your whole body (e.g. arms and shoulders) gets thrown into
the motion.

They're easier on the legs, harder on the whole body. (Assuming we're talking
about trekking across level ground here.)

------
kul_
another nice example of `less is more`.

------
dang
This was discussed at
[https://news.ycombinator.com/item?id=9315424](https://news.ycombinator.com/item?id=9315424).
This one is different enough not to be treated as a duplicate, but we did
change the title to a more informative sentence from the article.

~~~
araes
On the topic of dupes, within HNs Parent relationships, would it be possible
to create a meta-dupe tree? Basically, a meta-list above articles that adds
dupes (or maybe just closely related) as quasi-children of the "best" or
"highest comments" or whatever version of the article. If an article had a
parent you could just keep goin up to find the old one.

~~~
dang
I'm not sure exactly what UI you have in mind, but yes, we do eventually want
to have some kind of related-story grouping.

~~~
blahedo
Some ideas I had about that a couple years ago:
[https://news.ycombinator.com/item?id=1975950](https://news.ycombinator.com/item?id=1975950)

------
kazinator
There exists an amazing device which dramatically increases the efficiency of
body-powered locomotion, not to mention speed. However, it is more cumbersome
and cannot go to all the same places as an anke exo. This device is called a
"bicycle".

~~~
jmckib
I feel like this is a good time to remind you of HN's new guideline to avoid
gratuitous negativity. :) Maybe I'm misreading, but you seem to imply that the
creators of this device have never heard of a bicycle. Does that add to the
discussion?

[http://blog.ycombinator.com/new-hacker-news-
guideline](http://blog.ycombinator.com/new-hacker-news-guideline)

Downvoters: I'd appreciate if you would comment as well, since I can't imagine
why you would downvote me for reminding someone of our community guidelines.

~~~
twic
I haven't downvoted you, but i suspect that those who have have done so
because they parse your comment as identifying kazinator's comment as a
negative one, and that this identification is mistaken.

~~~
jmckib
I understand. Can you explain why I'm mistaken though? His comment came off as
fairly sarcastic to me, and didn't seem to contribute in any way. Surely most
of us know what a bicycle is already.

~~~
twic
Sorry, i meant that to read "and _they believe_ that this identification is
mistaken". I don't understand what gratuitous negativity is, so i don't have
an opinion on this myself.

