http://www.youtube.com/watch?v=S0_aje6u0tQ
I wonder if something like this could work??
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http://www.youtube.com/watch?v=S0_aje6u0tQ
I wonder if something like this could work??
I looked into this in the previous bout of BW enthusiasm. I think Tom Armitage even tried it out?
I believe at that size there wont be that much power and will struggle to flip 1.5kg...2 of em will probably do it...but...if you did an Envy style front hinge then the weight to flip is drastically reduced. I think it could work. I will try it when i have the arena done. I have a big sheet of 1.2mm Ti to build something very light weight so the electro magnet size can be increased.
The Big Nipper guys did an electric flipper with a massive solenoid back in 2012 with LF3. Part of it caught fire but it worked fine up til then. Ask them how they did it.
Maybe use something like this:
http://youtu.be/o_VjkUTZQXg
A kind of rail gun idea. I imagine it produces a force all the way along the stroke. I am imagining something more like the first test in the video rather then the second!
They work, but even the military are struggling to make it efficient.
The sheer amount of power you need in the first place is one problem (and batteries remain the thing which is holding-up many new technologies at the moment) but the real bugger is the size and weight of the components.
It takes a good couple of kilos in parts to make something that has the power of an air-pistol.
Give us carbon nano-tube batteries and hyper-capacitors, room temperature superconductors etc, and we'll see this become practical. Until then, it remains sci-fi waiting to happen. It's why the Large Hadron Collider is large.
And that's coming from your resident optimistic dreamer (me) Sorry :(
I did a ton of research into Solenoids in 2012 (talked about it on here) with the intention (initially) to do a FW. But then when the BN guys tried it I stopped.
Never fully explored BWs though.
If you got the same technology, but made your projectile spin on its axis instead of linear motion, then you'd need fewer coils and magnets with the opportunity to wind the coils very efficiently. Then you could just harness the rotary motion. That would be a lot more efficient. Take your research in that direction for best results...
Isn't that just a DC motor?
Quite a while ago the Chaos 2 boys built an antweight fliper from their pull back toy. It had an electromagnet but I think it was to keep the flipper shut and a spring is what did the lifting. I really cant remember it was over 10 years ago. It wasnt particulary good either, just really well made.
PJ is right. If you go down that route then you end up building a Kinetic flipper. Those work well but they are very hard to make. This guy has built loads but without assess to all the same tools its virtually impossible. http://www.wa4dsy.com/robot/flip-o-matic
YesQuote:
Originally Posted by PJ-27
LolQuote:
Originally Posted by Bacon Wizard
Dale's robots are very impressive!
What do you think of this:
http://www.youtube.com/watch?v=LYq2hHleLeM
Was thinking of using it for a FW but maybe its more suited for a BW
i like the concept....how would you return the catapult for another fire?
I strongly suspect that the size of magnets you'd need to get any real force into the flipper might put you well over weight. You're gonna want something with say 10 or 20 x the power of the one in the video, just for beetleweight.
Also, a possible flaw with the concept is that one of the magnets has to be in the flipper itself.. so that it already has to lift its own weight, as well as that of the flipper and the other robot.
If it were me, I'd still want to do more research before giving-up on the idea, but instinctively I'd wager this is a dead-end.
You'll have to use an electromagnet at the bottom and a perm magnet on top...the electromagnet should be twice as powerful tho, as the perm magnet will attract itself to the iron core...had tried something similar on a small scale and worked, but when it came to FW, the electromagnet would have been too heavy to get a similar force to a Co2 system
Jasper, neodymium magnets are super strong for their weight, as an idea a 250gr magnet has a force of 100kg. You wouldnt need that type of force for a BW for sure... for a FW its another story
You said yourself, it was too heavy for a feather. Although 980 Newtons of force for 250g is impressive, I agree.
Maybe the power/weight ratio is better on a smaller scale?
Ah, ok...I've been misunderstood 8) I meant this for a BW, for a FW I ruled it out and built a Co2 powered one. A 350kg electromagnet would have been too heavy and bulky.
But for a BW it might work.
This is a 20kg magnet... weighs only 46 gr
http://www.kjmagnetics.com/proddetai...CB-N52&cat=168
not a horrible price, either!