Live data from Hacker News

Origami-inspired soft artificial muscles

wyss.harvard.edu

11–20 of 60 posts

Re: Origami-inspired soft artificial muscles

#12

The 1000x comparison is silly - in a straight up lifting of things, a simple steel wire can probably lift 100000x times it's weight. The tech has it's uses and they should highlight the flexibility rather than perceived strength...

A steel wirte isn't lifting anything, it's just holding.

Re: Origami-inspired soft artificial muscles

#13
post #12

The 1000x comparison is silly - in a straight up lifting of things, a simple steel wire can probably lift 100000x times it's weight. The tech has it's uses and they should highlight the flexibility rather than perceived strength...

A steel wirte isn't lifting anything, it's just holding .

i don't understand what this means. you understand that g = 9.81 m/s^2 ... every second? the difference between colloquial lifting and just holding is a matter of applying on the order of just 1% more force.

Re: Origami-inspired soft artificial muscles

#14
This is tremendous and probably what all robots that interact with humans will look like in the next 50-100. Affordable flexible membranes able to grasp and grapple with our real world, and also gentle enough (when programmed correctly) to not harm humans and other beings, this is the future right here. Very exciting. Focus on the information and less on the headline, guys.

Re: Origami-inspired soft artificial muscles

#15
post #12

Earlier quoted context omitted.

A steel wirte isn't lifting anything, it's just holding .

i don't understand what this means. you understand that g = 9.81 m/s^2 ... every second? the difference between colloquial lifting and just holding is a matter of applying on the order of just 1% more force.

There is a difference between a material’s chemical bonds resisting the acceleration of gravity and actually being able to lift an object from one height to a second, higher height.

Re: Origami-inspired soft artificial muscles

#16
post #12

Earlier quoted context omitted.

A steel wirte isn't lifting anything, it's just holding .

i don't understand what this means. you understand that g = 9.81 m/s^2 ... every second? the difference between colloquial lifting and just holding is a matter of applying on the order of just 1% more force.

I'm not talking about force, but about energy. To hold something suspended in air, you don't need any energy. But a steel wire can't lift anything, you need to have a motor (or muscle) that actually expends energy to move the object higher.

Re: Origami-inspired soft artificial muscles

#17
post #12

Earlier quoted context omitted.

A steel wirte isn't lifting anything, it's just holding .

i don't understand what this means. you understand that g = 9.81 m/s^2 ... every second? the difference between colloquial lifting and just holding is a matter of applying on the order of just 1% more force.

[deleted]

Re: Origami-inspired soft artificial muscles

#18
post #12

The 1000x comparison is silly - in a straight up lifting of things, a simple steel wire can probably lift 100000x times it's weight. The tech has it's uses and they should highlight the flexibility rather than perceived strength...

A steel wirte isn't lifting anything, it's just holding .

But a steel wire can be reeled in using a reel. And if we don't include the airpump required for these origami muscles in our "muscle weight" then we don't need to include the winch weight in the case of the reeled wire.

Re: Origami-inspired soft artificial muscles

#19

They are basically inflating and deflating balloons filled with some flexible structure. So 1000x might not be that impressive, because they are very lightweight. And I guess it requires a big pumping device in addition to the muscle (which weight is not included in the calculation, but certainly should be).

The weight of the compressor is important, but one compressor could be driving lots of 'muscles' via opening and closing valves, so it isn't completely disingenuous. It's analogous to, say, a robot with six motors, all powered from a single battery.

A compressor driving more of these hydraulic actuators need to be larger and heavier than one driving one hydraulic actuator.

Rather than battery and many motors, its more like motor with many transmissions and clutches. Vacuum is also a bad choice of medium... It requires stronger pumps, stronger hoses, better seals, etc.

Re: Origami-inspired soft artificial muscles

#20

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.

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.

Post reply on HN