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Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

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Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#41

Post by jihadjihad »

drcongo wrote: post #39
emptybits wrote: post #20

His trebuchet launched a 4 gram projectile at 776 miles per hour. That's obviously extremely lightweight for trebuchet payload, but for comparison, his projectile is approximately 62 grains so approximately twice as heavy as 30 grain high speed 22LR rounds. And approximately 1.5 times as heavy as 40 grain subsonic rounds.

What does grains mean in this context?

It’s a super old unit of measurement for mass [0], idea being that a “grain” is a single seed of wheat etc.

1 gram is a little over 15 grains, and there are 7000 grains per (avoirdupois) pound.

0: https://en.wikipedia.org/wiki/Grain_(unit)

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#42

Post by 27183 »

It would be interesting to scale this design up. Not necessarily in terms of velocity--supersonic velocity for a large trebuchet munition isn't necessarily desirable. What I mean specifically is scaling up the multi-revolution arm and sling release technology to be capable of launching a ~1 ton projectile.

Could it be done reliably with traditional construction techniques (wood, treenails, lashings, minimal metal hardware)?

AFAIK these are innovations that were not explored historically. It would be interesting to see if they would have been viable. It seems like you could probably achieve a lot more downrange energy using the same amount of materials this way.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#43

Post by throw310822 »

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#44

Post by adlpz »

throw310822 wrote: post #43

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

You sound fun...

This is HN. The trip is the destination, bla bla.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#45

Post by shdwslrkr »

jijijijij wrote: post #38
daemonologist wrote: post #3

Also (mentioned by Tom), this elastic-powered supersonic trebuchet is an excellent video: https://www.youtube.com/watch?v=gdXOS-B0Bus

That device is so much more scary! Both really demonstrate the ridiculous amount of energy stored in a pinch of gun powder. And I presume gun powder is quite inefficient at driving the projectile, too.

[dead]

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#46

Post by WheatMillington »

throw310822 wrote: post #43

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

What a sad and pathetic opinion, especially when targeted towards such an incredible contributor as Tom Stanton, a true educator and an energetic and excited engineering mind.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#47

Post by Mashimo »

throw310822 wrote: post #43

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

Mate, you are on HACKERnews. We are all about this.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#48

Post by throw310822 »

adlpz wrote: post #44
throw310822 wrote: post #43

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

You sound fun... This is HN. The trip is the destination, bla bla.

No, I understand, it's the claim from the very first sentence that "gravity itself seemed to forbid" (reiterated later in the text) that annoyed me. It's just making up a non-existent obstacle to hype up the result.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#49

Post by throw310822 »

Mashimo wrote: post #47
throw310822 wrote: post #43

What's extraordinary about this? You can get any amount of energy from gravity and transferring it to a small object doesn't sound like an especially complex feat. It's one of those influencer videos in which someone devotes a disproportionate amount of effort to accomplish something pointless- Mr. Beast does the exact same without any pretense of showing something useful.

Mate, you are on HACKERnews. We are all about this.

Of course, but there is a continuum between "I spent years tackling this complicated problem and the solution will benefit us all" and "I've entered the same McDonald's drive-through 1000 times in one day to order always the same thing". Some achievements are closer to the first end, others lie more somewhere in between.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#50

Post by Razengan »

hinkley wrote: post #4

How do you responsibly test something like this? The payload isn't going to follow a ballistic trajectory, it's going to follow an aerodynamic one. You'd probably have to design something special to load into it to aim the damned thing. Which is a road trip to some place very empty in something like a 180º arc. Maybe 225º.

> How do you responsibly test something like this?

Into the ocean, I would hope

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