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Can Repelling Magnets Replace the Spring in a Pogo Stick?

kjmagnetics.com

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Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#111

Post by vvillena »

CydeWeys wrote: post #71
bleomycin wrote: post #51

Earlier quoted context omitted.

Every link i’ve seen to this story annoys the hell out of me because they don’t explain HOW the elevator eventually stopped. That’s literally all I want to know.

It reached the bottom. Probably hit one of these: http://elevation.wikia.com/wiki/Buffers Note that it wasn't descending particularly quickly; one cable snapped but other safety systems were still operable.

The article says it went from the 95th to the 11th floor. It appears it stopped before reaching the bottom buffer.

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#112

Post by quickthrower2 »

applecrazy wrote: post #31
umvi wrote: post #6

Seems like electromagnets could help compensate for distance by drawing more current when far apart, and less when close together. A microcontroller could essentially make the force linear like a spring. Of course, then you need wires hooked up to your pogo, and that might be scary if the microcontroller has a bug (or somehow fails) since you are now essentially hopping onto a railgun.

Not only that, but you can adjust the “springiness” by having a variable spring constant.

Using css animation-timing-function!

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#113

Post by vvillena »

hexane360 wrote: post #89
jolmg wrote: post #64

Earlier quoted context omitted.

But you have more time to react on a plane and switch to manual override. It's not like people fly with just a few meters distance to other airplanes. There's also a good distance to the only other thing you can crash into, the ground, as opposed to driving between walls or with a cliff to one side.

OP said "fly by wire", meaning there's no non electronic systems to fall back on. If the electronics fail there's no "manual override".

Of course there's a fallback. If the fly-by-wire system fails, there's another whole fly-by-wire system ready to take over. Usually this is safer than the old redundant hydraulics systems where all the lines ran close together, making them vulnerable to localized impact damage and fire.

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#114

Post by cheald »

randall wrote: post #27
azhenley wrote: post #19

Earlier quoted context omitted.

About as scary as my Tesla on autopilot going around a curve at 75mph. Every time I ask myself, what if there is a bug or if it turns off...

The downside risk is never worth it for me. I'm always hands on, and curves I treat it like a drivers' ed situation: You better do the right thing.

Yeah, I tell people that I treat it like a well-mannered 15-year-old driver - I expect it'll do the right thing, but I'm here to take over in case it finds itself out of its depth.

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#116

Post by briantakita »

Maybe a series of magnet pairs, spaced at different heights, could approximate the spring effect. Each pair would be bound together (e.g. with strapping) with the negative charge being on the outside, since Earth has a negative charge. The bottom of the stick would have the strongest magnet, negative charge facing up.

-

+

+

-

The pairs could then repulse each other at a closer distance, approximating the spring function. I accept royalty donations :-)...but it's probably patented by now.

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#117

Post by Animats »

damon_c wrote: post #54
azhenley wrote: post #19

Earlier quoted context omitted.

About as scary as my Tesla on autopilot going around a curve at 75mph. Every time I ask myself, what if there is a bug or if it turns off...

I have used Tesla autopilot on twisty cliffside roads (my hands hovering an inch away). The question in my mind was, when there is "nothing" there, is that a place it thinks is okay to go? Or is it a place a place where it should absolutely not go? I wish it could just tell me that.

It doesn't know about dropoffs. It only knows about lane lines. It's really good at following lane lines. Sometimes right into an obstacle.

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#119

Post by beefman »

Xcelerate wrote: post #22

I’ve often thought it might be interesting to replace the springs in a piano’s action with electromagnets so you could have control over the exact touch profile.

A guy named David Stanwood has a network of licensed piano techs all around the country who can replace the lead weights in the keys with magnets. One of the stated benefits is reduced key inertia.

https://www.stanwoodpiano.com

Re: Can Repelling Magnets Replace the Spring in a Pogo Stick?

#120

Post by dmurray »

umvi wrote: post #6

Seems like electromagnets could help compensate for distance by drawing more current when far apart, and less when close together. A microcontroller could essentially make the force linear like a spring. Of course, then you need wires hooked up to your pogo, and that might be scary if the microcontroller has a bug (or somehow fails) since you are now essentially hopping onto a railgun.

Maybe you can use regenerative braking to charge a battery, to avoid having wires and keep a bit closer to the spirit of the pogo stick.
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