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Can Repelling Magnets Replace the Spring in a Pogo Stick?

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

#141

Post by mirimir »

zaroth wrote: post #67
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 know exactly what you mean. I will admit at 20mph over the speed limit going over a poorly maintained curve on the Mass Pike I usually just disengage for a moment and then switch it back on. It can take the curve, but it doesn’t feel good to let it. I’ve had it lose tracking on the highway. It just leaves the wheel in the last position and beeps very urgently to let you know to take over. I find autopilot helps me…

> It will keep a clearly marked lane better than I can (it’s very precise with staying in the exact middle of the lane and doesn’t cut corner like humans tend to).

Anyone have experience with the lower Westchester County section of the Taconic Parkway? There are some serious curves, and the lanes are very narrow. In the left lane, you're maybe 2-3 feet from the box-beam center divider.

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

#142

Post by ryanmercer »

azhenley wrote: post #19
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.

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...

>what if there is a bug or if it turns off

Right? I have an irrational fear of laser eye surgery because I'm afraid some random component in the machine will fail and cause some sort of over-powered pulse.

It's far more realistic a component would fail in a car though and cause the 'brain' to take a shit on itself. Still pretty out there but it would be a very real concern of mine.

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

#143

Post by jhomedall »

gumby wrote: post #61
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...

Consider not going on a modern airliner. Every commercial passenger jet since the A340 has been fly-by-wire. (military jets have been so longer).

Aircraft autopilots and fly-by-wire systems are vastly more simple than self-driving cars.

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

#145

Post by labcomputer »

gumby wrote: post #81
bdavis__ wrote: post #66

Earlier quoted context omitted.

737 Looks like cables, air, and hydraulics to me.

737 is a much older aircraft. The A320 and subsequent Airbus jets and Boeing jets since 777 have been electronic.

The Embraer ERJ series does not have fly-by-wire, just to name one. So the assertion that every "Every commercial passenger jet since the A340 has been fly-by-wire" is simply false.

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

#146

Post by hammock »

diabeetusman wrote: post #99
hammock wrote: post #29

Can we make an electronagnetic-sprung mattress?

Ignoring other problems mentioned, what would the benefit of such a system be? I suppose it'd be very customizable, but probably expensive (both initial cost plus the cost of the electricity to run it).

I guess I was reading the other comments and thinking eminently customizable springiness - to the square-inch resolution. People pay outrageous amounts for Sleep Number beds. This would be the high-end version of that.

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

#147

Post by Too »

bleomycin wrote: post #51
Retric wrote: post #48

Earlier quoted context omitted.

Elevators use simple physical safety systems. Which is why you see headlines like: "Skyscraper elevator plunges 84 floors — and everyone survives" https://www.cbc.ca/news/world/elevator-plunge-chicago-1.4913...

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.

The basic theory is that between the car and the wire there is a spring connected to brakes. When the car hangs in the wire this spring is loaded and the brakes disengage, if the wire breaks, the spring returns and brakes engage. All this is mechanical.

What I never understood is how elevators can travel downwards so quickly without such a system engaging. Can they block it somehow or are they never accelerating fast enough down?

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

#148

Post by Too »

gumby wrote: post #61
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...

Consider not going on a modern airliner. Every commercial passenger jet since the A340 has been fly-by-wire. (military jets have been so longer).

Reliably implementing a few control loops and exhaustively testing all possible input/outputs for bugs - difficult but manageable.

Reliably implementing image recognition from multiple cameras and AI that should respond to ever changing weather, inconsistent roads, signs, maps and other human drivers erratic behaviour within milliseconds - Not even in the same league.

Not saying aircrafts are simple but self driving is just orders of magnitude more complex. Otherwise we would have seen them on the roads already.

Aircrafts also have much stricter maintenance schedules, failure investigations and completely different economic, media and moral incentives.

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

#149

Post by hexane360 »

vvillena wrote: post #113
hexane360 wrote: post #89

Earlier quoted context omitted.

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.

I specifically said "non-electronic" fallback.
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