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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?

#101

Post by dcwca »

CamperBob2 wrote: post #95
callalex wrote: post #83

Earlier quoted context omitted.

I agree that they should, but it’s pretty reductionist and arrogant to call it “trivial”. There is no such thing as a one-size-fits-all dynamic compressor. You would also need a fairly sophisticated content detection system (don’t distort anything that is music, which is a huge use case on YouTube for example). Not to mention adding _any_ steps to their intake pipeline requires more processing power and data moving t…

Speaking as a reasonably-experienced audio and DSP programmer -- and considering that the feature has existed in just about every home theater receiver for the past 20 years -- yes, it's trivial. YouTube has the advantage of being able to preprocess the audio track in its entirety, although most implementations work on a block basis and don't need that. A 'night mode' feature would take about one weekend's worth of w…

The audio compression / limiting can be done client-side, at playback time, offloading the cost of the operation

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

#102

Post by guipsp »

x220 wrote: post #100
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.

You don't have to think about buggy software to come up with death scenarios. What if a driver in the other lane is drunk or not paying attention? Another driver could kill you at any moment and there's nothing you could do to prevent it.

What are you talking about?

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

#103

Post by ehsankia »

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.

Could you not hardcode limits in your circuit, such that the maximum power it supplies is never enough to be deadly?

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

#104

Post by dedotated »

thaumasiotes wrote: post #96
nsxwolf wrote: post #92

Earlier quoted context omitted.

It could have slowed down gradually and stopped. The articles I’ve read don’t do a good job describing anything.

If it slows down gradually, it's not in free fall.

Guess again. The cable could break at floor 84, and the elevator car could travel through the next 50 floors, and not slow it’s descent until the 34th floor, at which point, given ten vertical feet per floor, it would still have a total stopping distance of nearly 200 feet, or 2/3 (66%) of a football field.

So, 500 feet of freefall is still substantial. That puts the situation on par with a bungee jump.

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

#105

Post by Drdrdrq »

dcwca wrote: post #101
CamperBob2 wrote: post #95

Earlier quoted context omitted.

Speaking as a reasonably-experienced audio and DSP programmer -- and considering that the feature has existed in just about every home theater receiver for the past 20 years -- yes, it's trivial. YouTube has the advantage of being able to preprocess the audio track in its entirety, although most implementations work on a block basis and don't need that. A 'night mode' feature would take about one weekend's worth of w…

The audio compression / limiting can be done client-side, at playback time, offloading the cost of the operation

Even better, the whole limiting could be done client side, in OS or browser.

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

#106

Post by CamperBob2 »

dcwca wrote: post #101
CamperBob2 wrote: post #95

Earlier quoted context omitted.

Speaking as a reasonably-experienced audio and DSP programmer -- and considering that the feature has existed in just about every home theater receiver for the past 20 years -- yes, it's trivial. YouTube has the advantage of being able to preprocess the audio track in its entirety, although most implementations work on a block basis and don't need that. A 'night mode' feature would take about one weekend's worth of w…

The audio compression / limiting can be done client-side, at playback time, offloading the cost of the operation

True, but that would involve modifications to the decode side of the audio codec. That's where the feature should be implemented (if not in the OS itself) but it's apparently not there. It needs to be supported on every platform, and deploying it wouldn't be anyone's idea of trivial.

On the server side, they could maintain a separate compressed audio track and switch to it when requested. They should have the ability to do that anyway for alternate languages and commentaries and such. Whether it would be more cost-effective to maintain a separate set of compressed tracks or to decode/compress/re-encode on the fly, I don't know.

It might be tempting to maintain caches of compressed tracks created on demand. That way they'd almost never incur a runtime penalty on the server, and also wouldn't have to pay a lot for storage. More than a weekend's worth of work at that point, though.

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

#107

Post by gpm »

ehsankia wrote: post #103
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.

Could you not hardcode limits in your circuit, such that the maximum power it supplies is never enough to be deadly?

Or hardwire? A fuse, just not having enough voltage, etc?

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

#109

Post by blattimwind »

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).

Depending on what fails how in a car, you may have less than a second to recover.

Apart from being hit with a high-explosive anti-air missile, I can't think of any failure mode in a plane that has such a narrow recovery window.

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