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Long-term log

A project log for linear actuations for everyone!

cheap artificial pseudo-muscles here

capitanveshdokiCapitanVeshdoki 05/22/2019 at 18:050 Comments

Hello everyone! This log gonna be long-term one (not long)
Why? Well, of course there would be an update about new version of control circuit, which should arrive .. in some period of time (says "Export of international mail" since 20th of May), but periodic logs about how things going are gonna be less periodic, because almost everything what can be done to make first version of an actuator a reality was done, really:

- control circuit is fully tested, it retains energy well and controls everything what needed, as beta-version it works amazingly well and I hope it gonna work even greater with a new PCB : )

- technology of stripe manufacturing is fully developed, reliable and easy, all problems were fixed, I like current design of stripes too, as it provides great pulling force
^ this picture represents duel with fluid dynamics and glorious victory (thanx, corn syrup!)

Of course, I've measured a pulling force, now I have a nice equipment for that!
Everything there is measured with 20kg magnets on each side and 10x10x4mm inside:
- stripe can reduce it's length at least on 60%. more? possible, but with different proportions
- stripe provides from 500 to 660 grams of pulling force on it's own, I found that pretty persistent!
- attraction force between big magnets (or electromagnets) increases pulling force - 1kg to 1.5kg

Only one thing is not ready - electromagnets. Of course, I've done one and showed it in previous log, but it still can't provide significant attraction forces - it has flaws. About them:
First of all we need to have a look at coil itself. Wire here (along with current) works as a source of electromagnetic field, shown on the left side, and further we place core from wire - weaker field becomes. We need this field to orient magnetic field of our core's material atoms, which works as an "amplifier".

That means: less layers of wire we have in our magnet - more efficient use of current we get.

Also, material of core really matters, parameter called permeability is significant - so we need to get best material we can. That's why I want to use hydrogen chamber, to make Fe annealed in it. As I told in previous logs - such a material has one of greatest characteristics which is possible to get, so it's quite helpful in that project, but requires some time and additional equipment.

Also, I want to upgrade coilformer, because it wasn't optimal

As stripe attracts to the core (mostly), fixating stripes directly to the core is the best decision. I want to do that by drilling 4 holes in the core and using steel wire (or something similar). I hope what my drawings are understandable enough - you can see there stripe is being held by a steel wire - compact and lightweight.

Current prototype of an electromagnet showed, that winding wire onto rectangular shapes is quite questionable process - it leaves gaps between core and coil (this is very bad), so i think, what I would use something between ellipse and rectangle for that purpose, then I would figure out how to cast properly.

Also, I would be happy to find someone, who is really into designing electromagnets!
And maybe has an idea how to make them extremely powerful, as never before : )
As they are effective as never before now, thanks for that decent control circuit,
I've thought a lot about that, I still can't find another approach, except of  using better core material

It would work, howeveeer... I think, that there should be a different way

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