Help in designing electromagnets

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Nmbr6
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Hi all,
First post, be gentle...

I'm trying to build a system based on the MIT Actuated Workbench.
They used electromagnets with the following spec:
1.9cm (0.75”) diameter x 3.8cm (1.5”) length, wound with 32-gauge copper wire with a total length resistance of 120-122 ohms, with no metal housings so to not focus the magnetic field.
They used 27 DC volts and draws about 250mA.

From what I read, it seamed to be an almost arbitrary choice though, so I was hoping to optimist the design to create more forces. I was also hoping to use a more standard 24V power supply (not sure why they used 27...)

I'm not sure where to start this process and I was hoping to get some advice.

I thought maybe some trial and error through a simulation tool could work, but tell me what you think (also for that, so far I saw recommendations for FEMM, MaxFEM, Vizimag, Elmer and OpenFOEM, so I could also use a recommendation for which one to use)

Thanks!
 
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Nmbr6 said:
so I was hoping to optimist the design to create more forces.

So is the question "how does one calculate strength of an electromagnet? " ? Any search engine should respond to that question.
The basic approach is amp-turns per unit length X permeability.
With 32 gage wire it's a sure bet they used copious turns and meager amps to get the amp-turn product they wanted.
You already know the amps, around ¼ .
To estimate # turns figure length of #32 to make 120 ohms. How many times will that wrap around a ¾ inch core?

The video you posted is long on applications but short on mechanical details.
They gave no clue how they detect position of a puck over the array of electromagnets.

Nmbr6 said:
I'm not sure where to start this process and I was hoping to get some advice.
It's hard to figure out what you are asking.