Saturday, 08/04/2023, 12:17

This one will be a really short Project Log, simply because I want to "officialize" and announce to the followers (since I literally made another Project Log inside of the previous Project Log in the form of edits) that I found an interesting alternative to electric motors.

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Edit²:

It seems that things will be okay-ish, I've made this illustration of the electromagnets in a "Z" or "staircase" connection configuration, and it gave an interesting result. It seems like it would make a twisting action on top of attracting each other:

Of course, I just twisted the bases because I thought it would be clearer to see the thing happening.

But I'm still not convinced, see:

When the squares representing the electromagnets connect to each other, it makes an "U" shape. And the cables that aren't touching or passing through the top/bottom plates would just be hanging loosely.

This means that I should have the bases in a "U" shape in order to make every electromagnet working together?

Or that I should put something flexible in the place of the plates, so it would actually work like an actuator?

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Edit³:

I found this scientific article that explores an electromagnetic artificial muscle, but for the life of me, my attention deficit isn't allowing me to read the damn thing.

"Development of an Electromagnetic Artificial Muscle - The EMAM"

This means that I can simply attach every single electromagnet to a rope/cable and all will act at same time to pull the rope?

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Edit¹:

I just remembered a fatal flaw with this idea of stacking up electromagnets:

Their force won't stack with it.

If you stack electromagnets one above the another, their force will stay the same, so their lifting force will be limited by its own strength.

Meaning that even if I stack them up, they will separate once the load goes above their limits.

I know I don't have a big brain, but goddang, sometimes I outdo myself.

Now I need to figure out a way of using electromagnets it said limitations.

The only three ways I could think of a solution was:

1- Using something similar to reversely actuated artificial muscles, let's say, the electromagnets squeezes rubber until it extends and then these disactivate gradualy in order to let the rubber actuate by itself.

2- Copy how the HASEL actuator works, but with electromagnets, the problem is that I don't fricking know how well it will work, since it would basically be an hydraulic muscle activated by an electromagnet. :|

3- Somehow, someway, distribute the force of all electromagnets throughout a line of metal plates parallel to the electromagnets.

Yes, this is an illustration of a dielectric elastomer, but imagine that one side of the "m" are the electromagnets moving 1mm each and the other side is a bunch of metal plates connected to a steel cable that will also move 1mm each.

... I just hope it actually works...

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On Project Log 40, I calculated a little bit how many watts of energy I would need in order to achieve the lifting capacity of 100kg and 1000kg, and in the case of the 1000kg, I found out that I would need 300 kilowatts of power, around 400-500 horsepower.

However, after looking at the electromagnets that are meant to lift 150kg and its power consumption of just 12 watts, I got the idea of just using a bunch of electromagnets stacked one over another in order to lift various tons.

Funny enough, I only checked this kind of electromagnet because I was looking for ways of making the electric motors cheaper.

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Of course, it is not that simple.

If you simply stack one electromagnet over another, you will lose electromagnetic power for weird physic reasons.

"This electromagnet (two electromagnets one above the other) would be like one with twice as many turns of wire in its winding. Since the magnetic field produced by a solenoid (and an electromagnet is nothing more than a solenoid with a soft iron core) is proportional to the number of turns, it would produce a magnetic field twice as strong. In that case, however, this doubled number of turns would occur over a length that is also doubled, which would reduce the magnetic field by half. Thus being doubled by the number of turns and divided by two by the length, the magnetic field would remain the same. Being able, therefore, to exert only the same force, that is, in this case, to lift only ten kilograms. But if they were placed side by side and, no, one behind the other, then, yes, they would be able to lift twenty kilograms."

So, you would need to screw an electromagnet to a non-magnetic plate (like wood?) and then point it to a metalic plate that would also have a wood plate and an electromagnet and so on until you achieve whatever tons of power you need.

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I also got confused if my logic was correct:

"If one were to stack 50 electromagnets one above the another in a 1mm distance, if all of these electromagnets were to close that distance to zero, would the entire stack of electromagnets shrink in 50mm or just 1mm?"

ChatGPT: The entire stack of electromagnets would shrink by 1mm, not by 50mm. This is because when the distance between two objects decreases, the effect of that decrease is localized to the immediate vicinity of the objects and does not affect the entire length of the stack. Therefore, each electromagnet would move closer to its adjacent electromagnet by 1mm, resulting in a total stack length reduction of 1mm."

Then I tested the hyphotesis on Blender:

If you can't tell what is going on in this screenshot, let me explain:

The bottom cube has 1 unit of height, I applied an "object modifier" on the cube so it self replicates 50 times in a direction of my choosing.

I choose it to replicate 50 times in the vertical direction and then inserted a distance of 2 units from the center of the cube, when you change this distance from 2 units to 1, it changes its verical size to 50 times. (by the way, I tried to set the point of multiplication for the surface/border of the cube, and the result was the same)

And thus, if you replace the distance from 1 unit to 1 milimiter... You get the idea.

I copied and pasted the same cube to the side so I could properly measure the distance between each cube.

So, yeah. This seems promising.

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Now I just need to figure out what materials I would need and how to avoid the electromagnets from magnetically interferring with each other.

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Also, In the case of the improvised electric motor with these lifting magnets, I was thinking of using them as a kind of stepper-motor.

Inverting the polarization of some magnets and keeping the polarity of other magnets in order to use the full potential of all magnets at the same time.

So, even if I had 60 electromagnets with 150kg of power working, I would have a holding torque of 10 tons using a fraction of the power of an electric motor.

But I don't know how well this idea would work since I don't really understand much about electric motors.