Hacker News Reader

Comment by fallingfrog | Hacker News Reader

It looks like this is some kind of pneumatic system, and IMHO if you're calculating strength/weight you would need to take into account the weight of the air compressor, to have a fair comparison with biological muscle. Not to mention the fact that air compressors need to have an energy source, and are quite noisy.

View on HN

The "big new thing" about this is that it doesn't use compressed air the way traditional air muscles do. It doesn't use compressed air at all.

You're probably going to say that vacuum pumps are noisy/heavy next. But this doesn't need traditional high-grade vacuum pumps, very low grade will work. And of course it is entirely moot for industrial machines that stand in place.

From what I can tell the trick comes from the pleating to massively increase surface area, giving atmospheric pressure more to work with.

I've been working with robotics (as a hobbyist) my entire life. This is the most exciting thing that I've seen in a while and I'll be building prototype knockoffs all week.

If you get something working I'd love to see a how-to article.

Heck, you could probably replicate it somewhat with a plastic baggie, some bits of cardboard, and a straw. Add some duct tape and hot glue, and you'd be set.

It could.

If you want to re-extend one of the muscles QUICK ;)

Potentially. But then for biological, you'd also need to include whatever system generated the ATP, oxygen, electric impulse, etc to power the muscle, right?

IMO, the crucial piece of information: how much pneumatic energy is needed per unit force for one of these, compared to that of more naive designs.

Given that the actuators are so light, it means that you don't need the extra power required to lift the actuator itself.

They indicate that they've had a 1000x increase, which means that to lift 1kg you only need force to lift 1.001kg instead of 2kg

I think that's a bit unfair. The importance of the weight of the muscles is how much has to be on a movable part. The compressor does not, depending on your requirements. It certainly doesn't need to move in the same way.

So its the limit, at scale. Build a big compressor, run a bigger machine with artificial muscle, the weight of the compressor becomes a small part of the whole.

Pneumatic to kinetic energy is much less efficient than electric to kinetic, so you're going to waste a lot of energy. And I guess the body is even better at energy efficiency

But apparently the efficiency of these muscle fibres are greater than that of electric ones. So maybe a win?

Reply on news.ycombinator.com