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How a car cigarette lighter works, in CT scans

lumafield.com

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Re: How a car cigarette lighter works, in CT scans

#21

Post by aaron695 »

throwup238 wrote: post #8
gwbas1c wrote: post #5

> this design, developed in the 1950s, is entirely analog Uhm, how is this analog? Perhaps "electro-mechanical?" Is there such a thing as a "digital cigarette lighter?" It's not like the electric circuit is an analog of the act of lighting a cigarette; as opposed to what we commonly use the word "analog" to mean that something in the system is an analog to what's being recorded or processed. (IE, in analog tape the m…

> Is there such a thing as a "digital cigarette lighter?" Yes: https://www.walmart.com/ip/Flameless-Cigarette-Lighter-USB-R... :-)

[dead]

Re: How a car cigarette lighter works, in CT scans

#22

Post by ofalkaed »

gwbas1c wrote: post #19
ofalkaed wrote: post #13

Earlier quoted context omitted.

It is an analog of a traditional burning fuel lighter. But they are using analog to refer to the fact it relies completely on analog circuitry and I suspect they actually wanted to point out the fact that it is 100% passive circuitry relying solely on the electrical and physical properties of a resistor (the coil) which is the interesting thing here, the resistor is its own temperature sensor. They sort of explain th…

> it relies completely on analog circuitry A resistor is not "analog circuitry" > the resistor is its own temperature sensor No, the clasp that holds the spring down is a bi-metallic strip that bends when it reaches a temperature. This is not "analog" because there is nothing for it to represent. The article is merely a case of calling something old "analog" without knowing what the word means.

A resistor is not circuitry, the resistor is a part of a circuit which in this case is analog.

Re: How a car cigarette lighter works, in CT scans

#23

Post by andrepd »

wumms wrote: post #17

> You might think such a system would involve a thermostat, a microcontroller, and an actuator, but this design [...] has bimetallic arms with steel on the outer surface and copper on the inner surface. As the filament heats up, the arms warm up, causing the copper to expand faster than the steel. This expansion pushes the arms open, releasing the lighter. The coil spring then causes the handle to pop out, signaling…

Heh, I correctly guessed the channel just by reading the title :)

Re: How a car cigarette lighter works, in CT scans

#24

Post by mystified5016 »

kube-system wrote: post #4

Seeing clever, simple, and reliable mechanisms like this make me think that digital electronics has really enabled modern engineers to be lazy.

Well, yes but.

Mechanisms like this can be extremely difficult to design. You have to go through many iterations to tune the performance and ensure it's reliable over a vast range of conditions. Then you have to do it all over again to make the design mass-manufacturable. The design is extremely sensitive to the quality of the input materials and could outright fail if not manufactured just so.

It requires a lot of education and ""real"" engineering. It takes a lot of very expensive engineer hours.

Meanwhile the digital equivalent is a weekend project at best, and can be designed by just about anyone with half a brain and one working eye.

I agree that mechanical mechanisms are almost always much more elegant and simple than a digital equivalent, but given that the digital versions exist and perform nearly as well (if not better), the pure mechanical solution just isn't practical.

I'm not entirely sure if this is a good or bad thing. It certainly feels like we've lost an art form, but are we simply moving from flint arrows to steel, or something more like the loss of Roman concrete?

Re: How a car cigarette lighter works, in CT scans

#25

Post by gwbas1c »

ofalkaed wrote: post #22
gwbas1c wrote: post #19

Earlier quoted context omitted.

> it relies completely on analog circuitry A resistor is not "analog circuitry" > the resistor is its own temperature sensor No, the clasp that holds the spring down is a bi-metallic strip that bends when it reaches a temperature. This is not "analog" because there is nothing for it to represent. The article is merely a case of calling something old "analog" without knowing what the word means.

A resistor is not circuitry, the resistor is a part of a circuit which in this case is analog.

This circuit does not "represent" anything, and thus is not analog.

Look up the definition.

https://www.dictionary.com/browse/analog

> of or relating to a mechanism, device, or technology that represents data by measurement of a continuous physical variable, as voltage or pressure.

Re: How a car cigarette lighter works, in CT scans

#26

Post by gwbas1c »

moolcool wrote: post #7
gwbas1c wrote: post #5

> this design, developed in the 1950s, is entirely analog Uhm, how is this analog? Perhaps "electro-mechanical?" Is there such a thing as a "digital cigarette lighter?" It's not like the electric circuit is an analog of the act of lighting a cigarette; as opposed to what we commonly use the word "analog" to mean that something in the system is an analog to what's being recorded or processed. (IE, in analog tape the m…

It's a valid distinction of the author to make. I don't know if there's such thing as a cigarette lighter which uses digital circuitry, but there theoretically could be. The way the lighter in the article works is both analog _and_ electro-mechanical.

No, go look at the definition:

https://www.dictionary.com/browse/analog

> of or relating to a mechanism, device, or technology that represents data by measurement of a continuous physical variable, as voltage or pressure.

Re: How a car cigarette lighter works, in CT scans

#27

Post by kube-system »

mystified5016 wrote: post #24
kube-system wrote: post #4

Seeing clever, simple, and reliable mechanisms like this make me think that digital electronics has really enabled modern engineers to be lazy.

Well, yes but. Mechanisms like this can be extremely difficult to design. You have to go through many iterations to tune the performance and ensure it's reliable over a vast range of conditions. Then you have to do it all over again to make the design mass-manufacturable. The design is extremely sensitive to the quality of the input materials and could outright fail if not manufactured just so . It requires a lot of…

I think it's more like Roman concrete. There are many creative engineering possibilities that simply aren't used anymore because there are so many jellybean parts on the shelf that can brute-force a solution without much creativity.

Much in the same way, I find many software engineers these days don't actually know much about how a computer or a computer network works.

Engineering is starting to become less about being masters of the physical world, and more like a discipline in gluing blocks together.

Re: How a car cigarette lighter works, in CT scans

#28

Post by ofalkaed »

gwbas1c wrote: post #25
ofalkaed wrote: post #22

Earlier quoted context omitted.

A resistor is not circuitry, the resistor is a part of a circuit which in this case is analog.

This circuit does not "represent" anything, and thus is not analog. Look up the definition. https://www.dictionary.com/browse/analog > of or relating to a mechanism, device, or technology that represents data by measurement of a continuous physical variable, as voltage or pressure.

I am an OED man myself.

>Relating to or operating with signals or information represented by a continuously variable physical quantity, such as voltage, spatial position, etc., which in the case of measuring instruments can be displayed on a dial or other fixed scale. Also: designating a signal represented in this way.

But the bimetal strip represents the data that is the temperature of the coil and the coil represents the data of the current. We can use both as sensors and we do, the bimetal strip was ubiquitous in thermostats until the rise of the digital thermostat and still used, resistors as sensors are still common and used all over the place in electronics.

Re: How a car cigarette lighter works, in CT scans

#30

Post by moolcool »

gwbas1c wrote: post #26
moolcool wrote: post #7

Earlier quoted context omitted.

It's a valid distinction of the author to make. I don't know if there's such thing as a cigarette lighter which uses digital circuitry, but there theoretically could be. The way the lighter in the article works is both analog _and_ electro-mechanical.

No, go look at the definition: https://www.dictionary.com/browse/analog > of or relating to a mechanism, device, or technology that represents data by measurement of a continuous physical variable, as voltage or pressure.

"represents data by measurement of a continuous physical variable"

Did you read the article? The cigarette lighter represents data (pops out) based on measurement of a continuous variable (temperature)

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