# Electronmagnet resistance ?

Discussion in 'General Electronics Chat' started by JwLeonhart, Jun 23, 2011.

1. ### JwLeonhart Thread Starter New Member

Jun 23, 2011
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I'm curious to know how strong two electromagnets would have to be to be able to resist each other and hold up an average human without touching each other.

Basically how strong would two magnets have to be to still be able to levitate and still hold up around 200lbs but at a decent distance.

I know you can take two normal magnets and turn the same poles towards each other to resist them, but I want to do this on a larger scale for a small project I have going on. I want to do something like a pogo stick... Imagine if you could bounce around on a pogo stick without a spring but with two magnets in a tube in place of it? Sounds like a more comfy ride lol.

I'm having alot of trouble finding information on electromagnet stuff anywhere and could really use some help on this.

I want to be able to have two magnets resist each other but hold up a decent amount of weight and not bottom out of each other... so say two magnets sitting 3" apart being able to hold up 200lbs without touching... is that possible or would I need magnets the size of jupiter with power supplies the size of mars?

Thank you for any help or input, i'd really appreciate anything!

2. ### MrChips Moderator

Oct 2, 2009
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Answers to last two questions: Yes, Yes

3. ### steveb Senior Member

Jul 3, 2008
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It's probably not practical to do what you want. It may be impossible, or at least extremely difficult and costly.

However obviously comparing to Jupitor and Mars is an exaggeration. Look into the subject of magnetic levitation. Both maglev trains and high speed energy storage flywheel systems lift large masses using powerful magnets. I think one way involves superconducting magnets, but the more practical way uses strong ordinary magnets, along with movement. So moving trains and massive spinning rotors can be levitated with magnets. However, this does not sound practical for a pogo stick. Also, cosinsider that the forces on a pogo spring are more than just the weight of the person.

Last edited: Jun 23, 2011
4. ### steveb Senior Member

Jul 3, 2008
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Last edited: Jun 23, 2011
5. ### strantor AAC Fanatic!

Oct 3, 2010
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To expound on that, a pogo stick comes to a point. It would be much easier to levitate something with substantial surface area. Consider the maglev train as mentioned, has plenty of surface area for magnets to repel. Your pogo might need a plate mounted to the bottom to give it some surface area, but then it will be a clumsier version of pogo.

6. ### Audioguru AAC Fanatic!

Dec 20, 2007
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Maybe you can make an electric pogo stick with a powerful electric motor driving a rack and pinion gearing arrangement. But the landings might be very rough.

A spring is better because it smooths and stores the power of each landing to help the next launch into the air.

7. ### strantor AAC Fanatic!

Oct 3, 2010
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I like that!
Or how about a pogo built around a big pneumatic cylinder. Wear a 4500PSI firefighter's Scott SCBA on your back. it would be so simple; a pneumatic limit switch mounted at about 50% of piston travel to automatically shoot you back up. Sky's the limit!

8. ### shortbus AAC Fanatic!

Sep 30, 2009
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They already have a high pressure gas spring pogo stick! Called a 'Vurtego' ; http://vurtegopogostick.com/

Back in the 1960's there was a gasoline powered pogo stick called a 'HopRod' also.

9. ### Audioguru AAC Fanatic!

Dec 20, 2007
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There is no video of the air-spring pogo stick. I saw something like that on TV where the rider nearly killed himself.

Frequently I dream that I can fly over people and things without a pogo stick just by holding in my breath. Maybe because my hobby is flying RC electric airplanes.

EDIT: I found the videos. The pogo stick is fantastic!

Last edited: Jun 23, 2011
10. ### djsfantasi AAC Fanatic!

Apr 11, 2010
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@Guru -- Someone else who dreams they can fly. My family thinks me strange. I "swim" in the air after a short hop off the ground. Perhaps electromagnet shoes would help me jump into the air...

Sep 30, 2009
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12. ### strantor AAC Fanatic!

Oct 3, 2010
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I've never heard of that; pretty cool, but passive. I was thinking something active, with valve to dump high pressure air into the cylinder to shoot you back up effortlessly; something similar to the operation of these shoes that shortbus linked to:

"They fire when the wearer steps down, pushing a metal platform away from the bottom of the shoe. This shoots the wearer up into the air. "

for a period of about 10 years when I was a kid, I used to have a recurring dream that I could fly by getting a running start and then pulling up on an invisible bar that was in front of my face, like doing a half-way-up inverted pullup. The harder I pulled up, the higher I would go. Coming down was really tricky; I would have to make tiny, slow adjustments or I would plummett. I often woke up from the feeling of falling when I did it wrong. The strange thing is that I would see what was in my neighbors' back yards and then when I would go peek over their fences the next day, it was really there, just as I dreampt it. people thought I was wierd. I guess some things never change.