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A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

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Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#171

Post by gxvwb »

sphars wrote: post #40

For those that don't want to go to TikTok's page (for one reason or another) there is a proxy service you can use, like how Nitter is used for Twitter, called ProxiTok. Gets just the video, description and ability to download it. The first video in the GP proxied: https://proxitok.pabloferreiro.es/@bsmachinist/video/7157587... Proxy info: https://github.com/pablouser1/ProxiTok (Not the creator of it but a user of it)

I hadn't heard of this either, thanks. I made a Firefox Add-On to redirect TikTok to use ProxiTok: https://addons.mozilla.org/en-US/firefox/addon/proxitok/

Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#172

Post by Maursault »

sudhirj wrote: post #5

Where does the heat go? That seems like a couple watts at least.

> That seems like a couple watts at least.

Unlikely. Light appeared to be around 5 lumens maybe requiring about 0.05A. If directly driven with 3.7V, then it's 0.185W. If he gets 20 hours of light, cell capacity @50mA is 1Ah, which seems close enough for the battery size, though maybe a little high, so LED draw is probably a bit less than 50mA and 0.1W, no where near 2W.

Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#173

Post by hamburglar »

kragen wrote: post #154
xeromal wrote: post #148

Earlier quoted context omitted.

Thanks for commenting. I'm a layman here so providing hard numbers helps me wrap my head around the comparison. I think you're saying that water is roughly double a better thermal insulator? I wonder if the man could devise a water layer around what generates the heat in order to reduce the chance for burning his body? He probably has to weigh the chance for water to mix with the components vs a simple titanium hunk…

I'm a layman too. No, I didn't provide numbers on thermal conductivity, just specific heat, though it is now unfashionable to call it that. Yes, putting some water inside the titanium would increase the thermal mass of the overall assemblage, and I don't know of anything that would work better than water for this. This would reduce the temperature to which the eye-socket tissue is heated by intermittent but high-inte…

> I think the more important issue here is that he's using low enough power with a low enough duty cycle that it isn't much of a problem.

Yeah, I think debating whether water or titanium is a more effective heat battery ignores the fact that titanium is obviously good enough, and there are plenty of reasons he might have preferred to construct the thing out of titanium, such as the fact that it looks cool.

Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#174

Post by kragen »

hamburglar wrote: post #173
kragen wrote: post #154

Earlier quoted context omitted.

I'm a layman too. No, I didn't provide numbers on thermal conductivity, just specific heat, though it is now unfashionable to call it that. Yes, putting some water inside the titanium would increase the thermal mass of the overall assemblage, and I don't know of anything that would work better than water for this. This would reduce the temperature to which the eye-socket tissue is heated by intermittent but high-inte…

> I think the more important issue here is that he's using low enough power with a low enough duty cycle that it isn't much of a problem. Yeah, I think debating whether water or titanium is a more effective heat battery ignores the fact that titanium is obviously good enough , and there are plenty of reasons he might have preferred to construct the thing out of titanium, such as the fact that it looks cool.

Because titanium is opaque, solid titanium looks the same as a thin shell of titanium on top of another material. Because water is liquid at body temperature, it isn't a suitable material to replace titanium for the outer shell; it would just splurt out of your eye socket.

Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#175

Post by hamburglar »

kragen wrote: post #174
hamburglar wrote: post #173

Earlier quoted context omitted.

> I think the more important issue here is that he's using low enough power with a low enough duty cycle that it isn't much of a problem. Yeah, I think debating whether water or titanium is a more effective heat battery ignores the fact that titanium is obviously good enough , and there are plenty of reasons he might have preferred to construct the thing out of titanium, such as the fact that it looks cool.

Because titanium is opaque, solid titanium looks the same as a thin shell of titanium on top of another material. Because water is liquid at body temperature, it isn't a suitable material to replace titanium for the outer shell; it would just splurt out of your eye socket.

> Because titanium is opaque, solid titanium looks the same as a thin shell of titanium on top of another material.

I obviously haven’t done the math and don’t have access to the data that would allow me to, but I suspect that for this application, you’d have to have an extremely compelling reason to complicate design and manufacturing with such an approach.

Re: A brief demonstration of my Titanium Cyborg Eye as a flashlight [video]

#176

Post by kragen »

hamburglar wrote: post #175
kragen wrote: post #174

Earlier quoted context omitted.

Because titanium is opaque, solid titanium looks the same as a thin shell of titanium on top of another material. Because water is liquid at body temperature, it isn't a suitable material to replace titanium for the outer shell; it would just splurt out of your eye socket.

> Because titanium is opaque, solid titanium looks the same as a thin shell of titanium on top of another material. I obviously haven’t done the math and don’t have access to the data that would allow me to, but I suspect that for this application, you’d have to have an extremely compelling reason to complicate design and manufacturing with such an approach.

Most people would consider not burning their eye socket and possibly brain an extremely compelling reason. Heating an entire 7-cc titanium ball from 37° to the 44° necessary to start causing burn damage would take about 30 joules: 500 mW for a minute, for example. If the heat source is close to the surface of the eyeball (on the inside) you would need less energy because only a part of the eyeball is reaching burning temperatures, maybe as little as a joule. If the ball is almost entirely full of water and properly insulated, you could probably handle hundreds of joules before it started to burn you through the teflon or whatever. A hundred joules is a 3.7 volt Li-ion battery with 7.5 milliamp hours of capacity, so this is a practical amount of energy to put inside your eye socket.
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