Four-legged tripod?

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Ben@Forest
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Re: Four-legged tripod?

Postby Ben@Forest » 6 Jan 2021, 9:24am

sjs wrote:
peetee wrote:
Tangled Metal wrote:Beat me to it. Fourth "leg" is a tentacle thing like the one that came out and searched the basement in that Tom cruise version of the film.


The flexible tentacle emerges from the base of the central section and appears to be the fifth appendage. The other four having apparently identical articulation and proportions, one being raised as if the machine were moving forward.


+1. There's a tentacle (coming from the base) and four legs. At first sight one of them looks like it comes from a point higher than the other three, but if you look carefully it doesn't.


I need to get one of these coins to look at before they're melted down!

Psamathe
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Re: Four-legged tripod?

Postby Psamathe » 6 Jan 2021, 1:08pm

Ben@Forest wrote:
sjs wrote:
peetee wrote:
The flexible tentacle emerges from the base of the central section and appears to be the fifth appendage. The other four having apparently identical articulation and proportions, one being raised as if the machine were moving forward.


+1. There's a tentacle (coming from the base) and four legs. At first sight one of them looks like it comes from a point higher than the other three, but if you look carefully it doesn't.


I need to get one of these coins to look at before they're melted down!

Are these made from the melted down Brexit 50p coins - the ones with the missing comma?

Ian

Tangled Metal
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Re: Four-legged tripod?

Postby Tangled Metal » 6 Jan 2021, 1:25pm

I think you're right. The front one looks like it's coming out of the top section. Actually looking closer, not easy on a phone but zooming right in there is a section going up into the upper body section. You're right! It's a fourth leg that somehow has its knee joint within the upper body of the craft. Very, very poor design even without considering the number of legs issue. There's no clear way for that front knee to be that high because it's in the body.

It's very poor design indeed.

peetee
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Location: Cornwall

Re: Four-legged tripod?

Postby peetee » 6 Jan 2021, 2:30pm

Tangled Metal wrote:I think you're right. The front one looks like it's coming out of the top section. Actually looking closer, not easy on a phone but zooming right in there is a section going up into the upper body section. You're right! It's a fourth leg that somehow has its knee joint within the upper body of the craft. Very, very poor design even without considering the number of legs issue. There's no clear way for that front knee to be that high because it's in the body.

It's very poor design indeed.


It joins the lower section as do the other legs. The upward section is slightly obscured by the downward section which is closer to ‘the viewer’. It’s foreshortened because in reality it would be the nearest appendage and closer than the body of the tripod.
As a technical drawing the perspective and proportions are very professional. A shame then that the illustrator has made such a glaring error. I wonder if they understood what a tripod was or read the word and saw it as ‘ tri pod’ rather than ‘try pod’?
Winter had arrived in the land of Kernow. Along with it came wet roads and cool winds.
“Oh, my wheels and coupling rods!” Peetee exclaimed.

Jdsk
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Re: Four-legged tripod?

Postby Jdsk » 6 Jan 2021, 2:34pm

Tangled Metal wrote:I think you're right. The front one looks like it's coming out of the top section. Actually looking closer, not easy on a phone but zooming right in there is a section going up into the upper body section. You're right! It's a fourth leg that somehow has its knee joint within the upper body of the craft. Very, very poor design even without considering the number of legs issue. There's no clear way for that front knee to be that high because it's in the body.

It's very poor design indeed.

The true knee has moved relentlessly upwards in horses. It's currently in or near the body. Seems to work well. Give it another 100M years...

Jonathan

Tangled Metal
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Re: Four-legged tripod?

Postby Tangled Metal » 6 Jan 2021, 5:59pm

peetee wrote:
Tangled Metal wrote:I think you're right. The front one looks like it's coming out of the top section. Actually looking closer, not easy on a phone but zooming right in there is a section going up into the upper body section. You're right! It's a fourth leg that somehow has its knee joint within the upper body of the craft. Very, very poor design even without considering the number of legs issue. There's no clear way for that front knee to be that high because it's in the body.

It's very poor design indeed.


It joins the lower section as do the other legs. The upward section is slightly obscured by the downward section which is closer to ‘the viewer’. It’s foreshortened because in reality it would be the nearest appendage and closer than the body of the tripod.
As a technical drawing the perspective and proportions are very professional. A shame then that the illustrator has made such a glaring error. I wonder if they understood what a tripod was or read the word and saw it as ‘ tri pod’ rather than ‘try pod’?


It looks to me that the knee is truncated like it's melted into the upper body section. Perspective might be ok but there's still something not right about it the fourth leg aside of course.

peetee
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Location: Cornwall

Re: Four-legged tripod?

Postby peetee » 6 Jan 2021, 6:10pm

The height of the knee on the nearest leg is consistent with the perspective. Being closest it will look artificially high as the viewer is very much lower as the sight line of the underside of the main body attests.
If anything the rearmost leg is ‘out of kilter’. If the legs emerged at every quarter point around the base it should be further to the right as viewed - but then they must be articulated around the circumference of the base so they can swing forward to take the next step.
But now we are falling into the realm of SciFi as a tripod of that stature would be very unstable if it could move. The mass of the body would sink towards the rising leg so locomotion would be next to impossible.
Winter had arrived in the land of Kernow. Along with it came wet roads and cool winds.
“Oh, my wheels and coupling rods!” Peetee exclaimed.

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661-Pete
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Re: Four-legged tripod?

Postby 661-Pete » 11 Jan 2021, 11:30am

peetee wrote: But now we are falling into the realm of SciFi as a tripod of that stature would be very unstable if it could move. The mass of the body would sink towards the rising leg so locomotion would be next to impossible.
I thought that too. H G Wells doesn't seem to have quite grasped that problem in the book. From Chapter 10, the first sighting of the 'tripods':
H G Wells wrote:And this Thing I saw! How can I describe it? A monstrous tripod, higher than many houses, striding over the young pine trees, and smashing them aside in its career; a walking engine of glittering metal, striding now across the heather; articulate ropes of steel dangling from it, and the clattering tumult of its passage mingling with the riot of the thunder. A flash, and it came out vividly, heeling over one way with two feet in the air, to vanish and reappear almost instantly as it seemed, with the next flash, a hundred yards nearer. Can you imagine a milking stool tilted and bowled violently along the ground? That was the impression those instant flashes gave. But instead of a milking stool imagine it a great body of machinery on a tripod stand.

In the 1953 movie, they ditched the idea of tripods altogether, instead they housed the Martians in flying saucer-like machines. But when Spielberg came along in 2005, technology had I suppose 'mastered' the problem of how to manipulate tripods on screen. I can't recall how they actually 'walked' (only seen the film once), perhaps someone can enlighten us?

I also recall the (unrelated) children's BBC series The Tripods, back in the 1980s. They certainly had tripods, though how often they were seen actually 'walking' I can't remember.

I suppose there has always been something sinister about 3-legged alien monsters in SF, because there is not a single 3-legged creature (other than amputees) native to Earth. A surprising fact.
Suppose that this room is a lift. The support breaks and down we go with ever-increasing velocity.
Let us pass the time by performing physical experiments...
--- Arthur Eddington (creator of the Eddington Number).

Jdsk
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Re: Four-legged tripod?

Postby Jdsk » 11 Jan 2021, 11:37am

661-Pete wrote:I suppose there has always been something sinister about 3-legged alien monsters in SF, because there is not a single 3-legged creature (other than amputees) native to Earth. A surprising fact.

Yes... but you have to word that carefully for it to work... : - )

Three legged amputee mammals get along pretty well.

And tripod stance or locomotion where some other organ is recruited isn't uncommon: kangaroos, meerkats, woodpeckers, parrots, tripod spiderfish...

"Three‐Legged Locomotion and the Constraints on Limb Number: Why Tripeds Don’t Have a Leg to Stand On"
https://onlinelibrary.wiley.com/doi/abs/10.1002/bies.201900061

Jonathan