My aging engineer of a father had an idea for a great design that keep getting updated in my head. He said he would like some kind of passive exoskeleton strapped on his legs and pelvis. When sitting though, it would put some springs in tension that would then help him lift back up. I think it could also be designed to have a locked mode to "sit" comfortably against any straight wall/tree.

[–] Maalus@lemmy.world 12 points 8 months ago (1 children)

Nothing new, it's called a pelvis orthosis.

[–] keepthepace@slrpnk.net 5 points 8 months ago (1 children)

Interesting! But after a bit of research I find nothing of the sort: either they are device that prevents flexion up to a certain angle but do not help movement or they are active motor-aided designs. Would you have an additional keyword or a link?

[–] Maalus@lemmy.world 8 points 8 months ago (1 children)

You basically found it. They relieve pressure on the joints, in addition to locking certain angles that hurt. Springs would essentially do the same thing, but more dangerous.

[–] keepthepace@slrpnk.net 3 points 8 months ago (3 children)

Helping upward movement is the whole point of the contraption, but thanks, I'll probably buy some of these and strong springs to do some tests.

[–] Maalus@lemmy.world 5 points 8 months ago (2 children)

Springs are some of the most dangerous things in engineering, especially strong ones. There is a reason why you don't fuck with the garage door. Anything happens - the person falls over, a bicycle hits them, etc - and it's a tragedy waiting to happen

[–] KevonLooney@lemm.ee 4 points 8 months ago (1 children)

This is how engineers die:

In 1940, at the age of 51, Midgley contracted polio and was left severely disabled. He devised an elaborate system of ropes and pulleys to lift himself out of bed. On November 2, 1944, at the age of 55, he was found dead at his home in Worthington, Ohio. He had been killed by his own device after he became entangled in it and died of strangulation.

https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.

Safety? What's that?

[–] JacobCoffinWrites@slrpnk.net 3 points 8 months ago

Considering that he also invented leaded gas and freon it's almost more like his bad inventions finally caught him personally

[–] ICastFist@programming.dev 3 points 8 months ago

Post your progress and results on the community, I'm curious!

[–] stabby_cicada@slrpnk.net 3 points 8 months ago

Not to discourage creativity, but I think there was a whole documentary about how bad an idea spring loaded exoskeletons are. Five Nights at Freddy's or something like that?

[–] technomad@slrpnk.net 2 points 8 months ago (1 children)

I wonder how much weight an effective design would add. It would probably need to be made out of some decent material, which would probably drive up the cost.

[–] keepthepace@slrpnk.net 3 points 8 months ago (1 children)

Aluminium would probably suffice, I doubt it would add more than a kilogram even if made of steel. You need an articulation that can hold let's say 150kg for an overweight person putting all their weight on one leg. It is not a crazy mechanical constraint. Bikes handle more with lightweight structure and more complex mechanisms.