Electromagnetic AEG

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Electromagnetic AEG

Post by mau5 » Sat Jul 14, 2012 2:10 am

I know I kinda brought up the topic a while ago, but I'm going to start playing around with the idea of an electromagnetic AEG. Finally got my first paycheck of the year so I ordered some magnet wire and after an amount of experiment with that I'll get some capacitors and a neodymium magnet. I have a plastic Crosman gearbox that I'll be using to play around with stuff, should make it easier to make modifications with a dremel or something. I think at first I'm just going to try attaching the neodymium magnet to the piston head then run the electromagnet and see what happens. I don't expect to get even 100fps with a .12g but I think it'll be fun to play around with anyways. Who knows, maybe I'll get some interesting results. So yeah, if anyone has suggestions, that would be greatly appreciated, and I'll post results as I go along if someone's interested. If anyone wants to kind of collaborate on the project with me, I'm completely open to that.

Putting this in Help because I'm probably going to be asking multiple questions as I go along, so might as well keep it to one thread.

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Re: Electromagnetic AEG

Post by Archer » Sat Jul 14, 2012 12:27 pm

mau5 wrote:I know I kinda brought up the topic a while ago, but I'm going to start playing around with the idea of an electromagnetic AEG. Finally got my first paycheck of the year so I ordered some magnet wire and after an amount of experiment with that I'll get some capacitors and a neodymium magnet. I have a plastic Crosman gearbox that I'll be using to play around with stuff, should make it easier to make modifications with a dremel or something. I think at first I'm just going to try attaching the neodymium magnet to the piston head then run the electromagnet and see what happens. I don't expect to get even 100fps with a .12g but I think it'll be fun to play around with anyways. Who knows, maybe I'll get some interesting results. So yeah, if anyone has suggestions, that would be greatly appreciated, and I'll post results as I go along if someone's interested. If anyone wants to kind of collaborate on the project with me, I'm completely open to that.

Putting this in Help because I'm probably going to be asking multiple questions as I go along, so might as well keep it to one thread.
Here's my first question, what exactly are you going to propel with the electromagnet? because it won't work on the projectile itself as would be the basic principle behind any electromagnetic launcher, because the projectile is plastic and not a ferrous material. so are you planning on using the magnets to power the piston?

the reason i ask is because the principle of an electromagnetic cannon is launch an (relatively) light ferrous projectile using a series of magnets that alternate being on and off to throw the projectile using a "wave" of magnetic energy.

Image

I don't know what exactly your planning, but this is what I know is considered a electromagnetic powered "gun" and the concept doesn't really translate well to airsoft.

now if your talking about powering the piston through electromagnetic power, thats actually what an AEG already is, because its powered by an electromagnetic motor.
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Re: Electromagnetic AEG

Post by Guges Mk3 » Sat Jul 14, 2012 2:35 pm

Not my place to discourage you...but your wasting your money in trying to apply it to airsoft.

Short of a radical redesign...there is nothing to adapt to a system that already works well with very little power consumption.
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Re: Electromagnetic AEG

Post by mau5 » Sat Jul 14, 2012 7:53 pm

Archer - It'll be powering a piston. The coils will be around the cylinder, and a neo magnet will be attached inside the piston.

Guges - I know, it's just for fun. Like I said, I'm not expecting anything practical. And I'm not buying anything specifically for this, I'll be using the wire and magnet for many many other things. I just like how the mechanics in airsoft can be easily understood but then there's so many properties that you can play with, and this is just putting an electromagnetic spin on it because I'm really into that right now. Side question, have you ever rewound a motor for airsoft, and if so, would you recommend it for someone who's experienced in rewinding motors?

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Re: Electromagnetic AEG

Post by Archer » Sat Jul 14, 2012 9:59 pm

mau5 wrote:Archer - It'll be powering a piston. The coils will be around the cylinder, and a neo magnet will be attached inside the piston.

Guges - I know, it's just for fun. Like I said, I'm not expecting anything practical. And I'm not buying anything specifically for this, I'll be using the wire and magnet for many many other things. I just like how the mechanics in airsoft can be easily understood but then there's so many properties that you can play with, and this is just putting an electromagnetic spin on it because I'm really into that right now. Side question, have you ever rewound a motor for airsoft, and if so, would you recommend it for someone who's experienced in rewinding motors?
I've not rewound them for airsoft, but i used to do it when i raced electric RWD buggies when i was younger. Its more practical for rewinding motors for things like the RC racing where the race motors can be 3-5x the cost of your typical AEG motor.

that being said there are some alleged and verifibile reasons to rewind electric motors (higher RPMS, better torque, less resistance, better reliability, etc) and can be done with some simple information, a lot of patience, some trial and error and a bunch of can-do attitude.

I suggest on reading up on rewinding motors for RC cars, as the principles will be identical, just scaled down a bit.
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Re: Electromagnetic AEG

Post by Guges Mk3 » Sun Jul 15, 2012 1:48 pm

You do realize the spring is going to mess with your electrical field, right??
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Re: Electromagnetic AEG

Post by SeawolfIV » Sun Jul 15, 2012 4:48 pm

Plastic spring? lol
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Re: Electromagnetic AEG

Post by Archer » Sun Jul 15, 2012 5:45 pm

Guges Mk3 wrote:You do realize the spring is going to mess with your electrical field, right??
not to mention that most metal pistons are made of aluminum, not steel to save weight.

and speaking of weight, how do you plan on generating enough magnetism to move that much weight at any sort of considerable speed?

the whole concept just isn't feasible, based solely on physics and the overall power of the force of magnetism in the size and amount of power were talking about here.

the amount of force that can be output in a small magnet, even the superpowerful, high-grade, neodymium magnets, is nowhere near what it would take to move something that large and heavy.

for example, take a neodymium magnet disk for example, 1 inch in diameter, .500 inch in thickness and of the grade N52 (one of the highest commercially available)
Image
Left side - Force (lb's)
Bottom - Distance (inches)

even with the magnet right next to the steel plate itself, its maximum possible pulling force is only 54 lbs (and thats in a perfect scenario directly attached to a large steel plate)

and that falls off VERY quickly in a short amount of distance. It looses OVER half of its pulling power in less the 1/10th of an inch. This is what im talking about when i say how weak magnetism actually is. the amount of power and coiling it would take to move a steel AEG piston itself would far surpass the amount of power it would take to run an ordinary AEG. Then, add into that mix that your either pushing that piston back against a spring of some kind, or your pulling the piston forward against some sort of return spring to pull it back again and you start multiplying the practical weight of that piston your trying to move. if you start multiplying weight with magnetic s, you start EXPONENTIALLY increasing the amount of magnetism that is needed, which means much larger coils, power supplies, and assemblies.
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Re: Electromagnetic AEG

Post by mau5 » Sun Jul 15, 2012 8:02 pm

Guges - There won't be a spring at all, the piston is being driven completely by the electromagnet.

Archer - Why would it matter whether the piston is aluminum or steel? Either way, the one I'm using is plastic. And I know it's not practical, I just want to make it work. I mean I made a tiny electromagnet with some jewelry wire and a 9 volt battery and I stuck a couple buckyballs (tiny magnet balls) in it and shot them out, and that was fun as hell. I mean this isn't a large project or anything.

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Re: Electromagnetic AEG

Post by Guges Mk3 » Sun Jul 15, 2012 8:23 pm

Then your may at least dribble a bb out a 50mm barrel.

And what are you going to do about a mechbox causing interference?

Another issue is they don't make a steel piston and aluminum has no magnetic properties.

You have to look at the BIG picture. Otherwise...your wasting resources.
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Re: Electromagnetic AEG

Post by mau5 » Sun Jul 15, 2012 9:25 pm

I might just take out the piston and cylinder and try that on its own, so gears won't be a problem. I don't need the cylinder to have magnetic properties, it's just to wrap the coil around. Coil around cylinder, magnet inside piston, turn electromagnet on, piston comes forward. Am I misunderstanding something?

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Re: Electromagnetic AEG

Post by Archer » Sun Jul 15, 2012 11:26 pm

mau5 wrote:I might just take out the piston and cylinder and try that on its own, so gears won't be a problem. I don't need the cylinder to have magnetic properties, it's just to wrap the coil around. Coil around cylinder, magnet inside piston, turn electromagnet on, piston comes forward. Am I misunderstanding something?
yes... your misunderstanding the very principle on how what you did before compared to what your attempting to do now works. The piston simply isn't going to shoot foreward with enough force to propel a BB down a barrel with any more force then it would if you simply dropped it down the barrel. If that much at all....

electromagnetic coils don't have a long enough "stroke" when moving objects to power a piston like this. A piston in an AEG moves forward against resistance (from friction of the side walls, the friction of the gears, the drag forces of the air, the pneumatic back pressure created which is what actually pushes the bb down the barrel to begin with, all this ON TOP OF the actual weight of the piston) for a travel of a good inch and a half to two and a half inches (depending on mechbox version)

A magnetic coil exerts a tiny amount of force for just about 0.2 of an inch....

do you see where this is adding up, or to be more correct, NOT adding up? your powering a system that requires a slow/constant application of force over the duration of time it takes the piston to go from completely back to completely forward, a distance of a couple inches, with a power source that is expending all of its energy in less then 5% of that distance. Not to mention that it doesn't have the sheer driving power to push the bb out to begin with, even if it did have the constant, long stroke power that it needs...

Its like trying to push a car in neutral down the street by kicking it.... its not near enough of the wrong application of force.
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Re: Electromagnetic AEG

Post by Guges Mk3 » Mon Jul 16, 2012 7:36 am

Archer wrote:
mau5 wrote:...Its like trying to push a car in neutral down the street by kicking it.... its not near enough of the wrong application of force.
Yay! Car analogies!
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Re: Electromagnetic AEG

Post by mau5 » Mon Jul 16, 2012 12:49 pm

Yeah I figured something like that would happen. I mean when I pictured it in my mind it just seemed like once I ran the electromagnet, the piston would jump forward maybe a quarter inch then stop because of all the pressure. I just liked the idea of something that would release energy quickly. I mean that's the problem with an AEG, using a motor and spring as your driving mechanisms means you have constant FPS but you have a whirring motor and you're sacrificing ROF (which is obviously better than constant ROF and varying FPS). It's kinda funny how even after you figure out your energy source (battery) which seems like the biggest issue, it's even harder to find a way to deliver it how you want (perfectly consistently, immediate release of same amount of energy each shot). That's why I've been looking into getting a gas gun, but they seem too finicky, and polarstar is too expensive. Are there no pneumatic mechanisms that collect pressure from a tank until a certain psi and release it the same each time it's triggered (and can only be released once it's collected all of the pressure)?

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Re: Electromagnetic AEG

Post by Guges Mk3 » Mon Jul 16, 2012 1:08 pm

Your addressing the issues that happened in airsoft back in the 20th Century around the 1980's.

This is why TM is the pioneering powerhouse that they are.

Look at the issues that was prevalent back then in this video and look how the AEG solved that issue.

http://www.youtube.com/watch?v=qjdP4pQFHoY
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Re: Electromagnetic AEG

Post by mau5 » Mon Jul 16, 2012 6:49 pm

Interesting. Other than the fusion engine, are there any possible new technologies in airsoft?

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Re: Electromagnetic AEG

Post by Ninjaofdeth » Mon Jul 16, 2012 7:17 pm

mau5 wrote:Interesting. Other than the fusion engine, are there any possible new technologies in airsoft?
Isn't that sort of like asking what hasn't been invented yet? There will always be something new eventually

Anyways, while Guges and Archer are almost certainly correct that you won't be able to make an AEG using electrical fields in any other way than an electric motor (unless you just straight up made a coil gun and called it an AEG), don't let that discourage you from experimenting. Experimenting is where the fun is. If you understand that you probably won't get what you want, and if it doesn't cost much of your resources, you might as well try it and see what happens. Don't go into it thinking you'll make a perfect airsoft gun or invent a super awesome new technology, just do it to see what happens.
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Re: Electromagnetic AEG

Post by mau5 » Mon Jul 16, 2012 7:45 pm

No, I just mean if there's been some talk of something new. I know it won't work well, I just want to play with electromagnets. And I got the wire in today so I'll start soon.

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Re: Electromagnetic AEG

Post by SeawolfIV » Thu Jun 06, 2013 9:33 pm

Well, fellow naysayers, it looks as we may be defeated. A retired electrical engineer is (unfortunately for us) on the case.

http://forums.airsoftmechanics.com/inde ... ic=10190.0
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Re: Electromagnetic AEG

Post by Guges Mk3 » Thu Jun 06, 2013 9:35 pm

You link only works if your a member of ASM
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relevant posts from link

Post by SeawolfIV » Thu Jun 06, 2013 10:51 pm

This is 5 cached pages. If I have time, I'll post results. Otherwise, you should just make an account if you're interested.
------------
setup:
username
post
------------
awlogue
Hi all
Most of you would probably say that springs are somewhat of a hassle sometimes. Choosing the right one, inconsistencies between different brands, closing the gearbox, breaking, etc. are all things that'll put you off of teching for a night.
Frustrated with springs in general one night I had the thought of using electromagnets, or even permanent magnets, to replace the mainspring. Electromagnets would be the best, as you could potentially adjust FPS by adjusting the amount of current that flows through the coils.
Another thing that would be great with this idea is trigger response. Instead of having to wait for a motor to draw back the piston against the spring, there could be a timing circuit that would trigger the electromagnet just as the sector is done drawing the piston back (at it's highest rpms for that great response).
So- how do you guys like this idea? I think, if done properly, magnets or electromagnets could replace springs in a lot of setups we use, possibly even extending to BASRs. Let the discussions begin!

seawolfiv
Meh this idea got tossed around on my local forum a year our so ago. Not optimistic. viewtopic.php?f=5&t=34869&p=323447&hili ... et#p323292

ben3721
You would only have one magnet since the magnets would skrew with eachother. But for the powering of the main piston it would be neat and IS do able but the technolgy has not been developed yet. You'd need a decent sized magnent in the piston with a repel coil behind it. Its hard to to repel electromagnets. Don't get me wrong electro magnetic air rifles can be done. Just don't us a TM mechbox. All so I think it would require a lot of volt rather then amps. Correct me if I'm wrong.

awlogue
What forum is that? I want to read it now.
One permanent magnet, possibly where ACM piston head "weight blocks" usually go, could possibly work. I was thinking of putting the electromagnet coil where the spring guide is, if using a TM spec box. You're probably right that it's not too feasible for TM specs.(What about DSGs though? That would leave enough room for pretty much double the coil space)
Voltage vs amps- I honestly couldn't tell you which is more needed. But a lot of it, whatever is needed.

krap101
I think the issue lies in that capacitors of any meaningful capacity are quite large, and I doubt a system which could fit in a gun would have a usable fps. The second thing is you'd either need a return spring, which would increase the size further, or be able to reverse the current direction, which might inhibit the rof.

knappster
A large problem to overcome would be magnetic braking as the magnet moves very fast inside the gearbox. You'd have to have a plastic or composite shell (and receiver possibly) so you don't have eddy currents slowing things down.
A spring is really good at storing potential energy and releasing it very fast. To achieve the same with an electromagnet requires generating a hell of a lot of magnetic flux in a really short time. Easy for a large capacitor bank charged with high voltages but slow to charge from a battery, and really really dangerous. Also the strength of attraction is very exponential, if you were trying to push a piston with an electromagnet it would start off moving with some strength but would very quickly give up when it's moved away.
You might get somewhere with a pulling system. A coil pulls the magnet at the end of shaft that runs through the coil connected to the piston head. You'd also need a return spring so your coil would have to have enough power to pull the piston and spring.

beautyinsidethebox
Why not aluminum? We already use CNC aluminum for a lot of stuff, is even aluminum enough to throw off a magnet?

superfetus
I remember a post on this forum where a user installed a magnet in his piston for cycle detection with a hall-effect sensor. He experienced a 10% power drop afterward, presumably from the field it induced in the cylinder.

krap101
You'll still see braking from aluminum

Gandolf (the retired electrical engineer, also the Extreme Fire owner (cheetah fet maker) )
I played with this a lot but with magnetic induction as opposed to fixed magnets. Here are some of the basics.
The BB fires at say 1 Joule and the efficiency is about 10% so the power system has to do at least 10 Joules. Maybe it could be better, but plan for the worst there.
About 20 volts is the safest voltage you can play with in the rain. So 18.5V LiPO is a nice battery and that is in the range of say the 3034 FET.
Of course the magnet on the piston is Neodymium and all that:
http://www.forcefieldmagnets.com/catalo ... Path=23_37
So the main cap size is now known...
E = 10J = 1/2 C x V^2
C = 60,000uF at 20V...
http://www.digikey.com/scripts/dksearch ... ageSize=25
I hope that URL works...
http://www.digikey.com/product-detail/e ... ND/2269427
http://www.digikey.com/product-detail/e ... ND/2095924
So those caps are 2 in diameter x 3++ inches long....
So capacitive discharge is probably out due to size unless you did something really high voltage which would be deadly...
Also the 0.009 ohm resistance... Not really a problem... But have to watch that...
So you would have to run the whole show directly off the LiPO battery...
10J = 18.5V x I I = .56 amps but that has to be over say 1/1000th of a second or 560 amps...
So right off we pretty much know it would need to be powered by a big 18.5V LiPO directly at about 500 - 1000 amps for a few milliseconds...
So 18.5V LiPO capable of 1000 amps fired with a 3034 MOSFET for say 4mS. Use i large gauge coil and those super magnets on the piston. I don't know what it will do, but it WILL do something
Wear good safety glasses for sure!
T.

Gandolf
Actually, it is a very good idea!!
Prolly two 11.1V LiPOs in series since that is so easy.
I don't know the piston travel time but let's just say it is 2mS...
10J = 22.2V x I x 0.002 I = 225 amps which is pretty trivial...
225^2 x 0.002 x 0.002 x 20 RPS = 4 watts dissipated on the MOSFET.
That is all within the range of our tech you know...
T.
Update:
So now we know some important specs to work with...
22.2 V LiPO at ~1000 amps range to drive it at first experimentally...
Pretty simple 3034 style MOSFET switching probably with a lot of TVSs for kick backs on the coil.
The piston is conventional but with Neodymium magnets of some size to give the most force with the least mass to be drive forward really fast.
I have no idea what the coil size, turns, or all that is...
I don't know the time it takes for the piston to go from rest to full forward or the profile. That is pretty important to know how to make it so in our case....
The electronics for the drive system is like a very simple triggered 555 timer circuit. It just turns the current and voltage on full blast for some time like say 15mS and turns back off... Super easy to adjust...
We would need a piston and electromagnet assembly for it to drive... I normal piston with a big super magnet and copper coil around it is all...
The SW-LION is nice for this since it could record times, voltages, and currents, during testing....

beautyinsidethebox
where would one find a 1000 amp constant discharge Lipo? A Chevy volt?

davisev5225
Get pairs of these to wire parallel to each other, such that you have 2 parallel arrays in series.
http://hobbyking.com/hobbyking/store/__ ... _Pack.html
You'd only need 6 total.

Tuanicle
To reset the piston, you could just build it as a BASR, and use the bolt to pull the piston back, assuming the electromagnet is off. Also would the be any way to control or stop the magnetic fields? Depending on how strong electromagnets are, you might start to mess up you gear, as well at any other metal stuff.
There is a reason you can't have metal inside MRI rooms

philsaudio (also a retired engineer; audio, I believe, but I could be wrong)
You will get far more force attracting the piston to the electromagnet than by launching it with the electromagnet.
Probably the best result will be had by attracting the piston, then changing polarity / direction right before the piston collides with the cylinder head. Have a permanent magnet in the piston to use in conjunction with the electromagnet in the front of the cylinder and to hold the piston back so when it is called forward it starts from a known position.
I discovered this phenomenon whilst optimizing the system that propels a baby in a baby rocker.

knappster
You shouldn't need to reverse the polarity, just switch it off, the collapsing field should do the rest.

Gandolf
We only need to draw the high currents during the actual firing - not all the time like 22.2V at 500 amps for 0.005 seconds. That is 55.5 joules so at 10% the BB would fire at 5.55 joules. The power would be adjustable by controlling the on time of the firing pulse. Having too much power is not a problem.
One would probably want to use 2 x 11.1 volt batteries so you can use a typical 11.1V LiPO charger. I don't think mine will charge 22.2V LiPO... These look fine!
http://hobbyking.com/hobbyking/store/__ ... _Pack.html
A small return spring would probably be easier than reversing the voltage (H-Bridge vs. one FET). There is no main spring now so the force to return the piston is very low..
5000mAh is....
5A x 3600s x 22.2V = 400000 Joules or 7200 shots per charge (55.5J/shot).
At 30RPS the running power is 55.5 x 30 = 1665 watts. That's pretty high but you can always turn it down. If the BBs shatters cinder blocks then it is too much energy Having too little energy is the big worry.
I will sketch something up and see about getting a few simple parts to see how it all works.
Here is what I was thinking. First the mechanical parts:
Image
The parts here are all conventional airsoft parts with the exception of the piston return spring, magnet, and piston coil. There are no motor, gears, spring, cutoff, or selector parts anymore.
Piston return spring - The piston is now free to move around easily but we want it to be normally pulled back. This light spring just slides it backwards in the rest state.
Neodymium Magnet - A 0.75 x 1/4 inch ring magnet.
Piston coil - A coil of heavy wire around the piston. When this coil is energised the piston is pulled forward and the BB is forced out the barrel just like any other airsoft gun.
That really is all there is too it. All the other messy parts are eliminated. One problem is how to do the tappet plate now with all the gears gone. One should be able to link it to the piston travel somehow though.
For the electrical part:
Image
B1 and B2 are just two big high current 11.1V LiPO Batteries.
F1 is a poly fuse to turn it all off if something goes wrong.
L1 is the main piston coil.
Q1 is pretty normal 3034 MOSFET to switch the current.
S1 is the gun's normal trigger switch.
R2, C1, and R3 form a pulse from the trigger switch to trigger U1.
U1 is an LMC555 timer. It does the on timing and FET drive.
R4 and C2 determine the piston coil on time. It can be easily adjusted as needed.
B3 is just a 9V battery to run U1 but it could be run from the main batteries too with some more parts.
So not much too it really. Probably want a big TVS or two across Q1 and F1 would take some testing to get right. A CPU chip and all could do the full auto and ROF timing very easily.

acelafan123
Wouldn't there be a significant amount of stress to the gearbox shell and wouldn't the neo magnets shatter because they are pretty fragile?

awlogue
If there is sorbo they should not shatter unless an unnecessary amount of force is applied directly to them for some odd reason.
Also to Gandolf- Would it be better for the neo magnet to be in the back of the piston in order to get the most time possible outside of the coil? Am I wrong in thinking that the piston will decelerate once it is inside the coil?

davisev5225
As I understand it, a magnet will always accelerate in the direction of current flow when placed inside an electro-magnetic coil.

knappster
Here's another insane idea.

If you passed a current through the main spring of an AEG would it compress enough so that when the current is released it would have enough force to fire a BB. It's common knowledge that a spring compresses when current is passed through it but I think you'd need an insane amount of current to compress the spring enough. Then again there might be materials you can make a spring from that would enhance the effect, like nitinol wire.

Gandolf
That would be cool! The same drive circuit could be used to test that.
The tapet could probably be magnetically coupled to the big coil too to operate it. Or some kind of sliding or rotating sleeve thing like how I would have done it in the first place.
I hope the neo magnets don't shatter... Have to see if that is a problem. Maybe a little cushioning.
One can put the magnet in the back of the piston or anywhere. I was just trying to make it simple to use existing parts to try it out.
One problem is that the cylinder looks like a shorted turn to the main coil right now. The voltage is low so maybe it's resistance and poor coupling will make that OK but it is something to watch. If the cylinder melts like it is in an induction furnace then IDidItWrong.jpg
So I am looking around for parts today to give it a shot so to speak. I think I have everything but the magnet and a barrel. I can just get 1/4 inch tubing from the hobby shop and the sleeve too. I have this big 1 Farad capacitor (72 joules) for the battery at the moment. That save $110 for the first testing but it's voltage will drop very fast.

-various members-
-messages of thanks for funding research-

Gandolf
Ok, I got the magnets on order!
But it might be better to have the electromagnetic coil/piston inside the stationary neo magnets in the end... Like Woofer speakers or the 60's/70's era tape drive motors...
I am thinking of making a bolt action single shot sniper rifle at first if this all goes swell.... With a 50 shot magazine that reloads in 0.5 seconds in case you miss a lot like me!!
It really is a whole new animal of airsoft gun!!!!!
But first, we have to get the SOB firing BBs of course....
Light a fire for a man, he'll be warm for a night; light a man on fire, he'll be warm the rest of his life.
Winnie the Pooh wrote:Oh brother
as he chambered another round.

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mau5
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Re: Electromagnetic AEG

Post by mau5 » Fri Jun 07, 2013 3:53 am

Funny, just a couple days ago I was preparing to buy materials to do some test runs with this, but decided to ditch it after reading over this thread again. Probably wouldn't have worked out well with my little experience though. I do have both a plastic Crossman gearbox and the longer-stroke guts of a Well l96 (sorry Digital) which would work pretty well as a platform.

I'm going to make an account on that forum and try to follow the progress of this. If at some point they put up a video of a working piece (I know, probably won't happen), I'll probably post a thread about it here just for the sake of spreading attention. Good stuff, Seawolf. Thanks.

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