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This evening, in a bar, having a bite to eat, the telly was showing Spencer Kelly with his BBC Click program from the CES where he was very rapidly going through a range of new gadgets. The sound was turned down.

Then I saw him with a row of plastic tumblers with varying levels of water in them that he was holding a device up to - it appeared to be detecting the levels in each tumbler. However, before I could get the bar staff to turn up the sound, he'd moved onto something else..

So, back in my room, I've just gone into Iplayer to see the program again - but it won't play because I'm outside the UK..

Could someone watch this program and tell me if the gadget actually does that? - it could be very useful for checking bottles with opaque glass..

I'm afraid it wasn't a level detector - it was for checking water contamination - effectively an electric field sensor.

As for how you could detect the levels... Depending on the type of glass, some spectrum of infra-red might be able to pass through glass, but struggle through the wine.
Another option could be to fire a laser that could pass through both the wine and the liquid. As you move it up the bottle, the light will diffract at some angle. When you leave the liquid (and just have bottle) this angle should change. I guess the problem with this method would be the varying shape of the bottle neck.
As I work in a laser lab, I have a few bits and pieces that I might be able to have a play with... I'll try report back.

As I'm approaching the last few months of my PhD, what better idea than to procrastinate trying to make a level sensor?

A quick description of the setup.

In this experiment, we are measuring the level of the water in the beaker off to the right. As I couldn't be bothered to hook up a motorised sensor to move up and down, I added water into the beaker until I could detect it.

As for the sensor, I tried two methods.
1. A small coil
2. Two pieces of foil (one active, one grounded)

To measure, I used a Vector Network Analyser. This effectively measures the Impedance (how inductive/capacitive/resistive something is) from 100KHz to 20GHz.
Long and short, I'm measuring changes in the electromagnetic field from the water to air

Results
The small coil was able to detect the level when going from air to water fairly accurately within a few mms. Going from water to air, is harder to see due to the ease of seeing a peak created as opposed to destroyed.

The pieces of foil produced and interesting result somewhat highlighted by that image. The peaks would be created and destroyed (and i can reproduce these) moving up and down, depending on the level, again with few mm accuracy.

Conclusion
I appear to be able to measure the level through a glass. I also tried this with a tiny bottle of Tokaji I had lying around and could get similar results, even with a tapering neck.

The entire setup is very flimsy and noisy and with some actual effort put into it, could be made much better. Also a motorised sensor to run up and down would help greatly.

How to make your own
Co-Axial Cable ~£1
Co-axial adapters ~£2
Foil ~50p
Inductor/Coil ~20p
VNA ~£40,000 (every good household should own at least one of these)

I think the most impressive part of this experiment is that you happened to have a bottle of Tokaji lying around in that lab

Well, a splendid effort

I can't help thinking there's a job waiting for you on Blue Peter..

..now children, here's how you can make your very own MRI scanner...

DRT wrote: ↑19:37 Mon 14 Jan 2019 I think the most impressive part of this experiment is that you happened to have a bottle of Tokaji lying around in that lab

Us quantum computing folk have better taste than the rest of physics.

I would like to next try some light based methods but I don't have a bottle dark enough. If any of you would kindly like to donate an opaque bottle (preferably unopened and of quality vintage), then I'd be happy to get our laser table on it...

Where would the bottle be needed?

So if all goes well, we just have to mount the laser table in some form of portable unit like a backpack with connected hand instrument, and probably wear protective goggles; likely we'd also need a protective suit for health and safety in case of contaminated bottles or breakage. Then we'd be suitably equipped to provide a public service:
"If there's something weird, that's been aged in wood, who ya gonna call?
If the capsule's weird and it don't look good, who ya gonna call?
Level-assessin' makes me feel good!"
Don't cross those beams!

AHB wrote: ↑21:35 Wed 16 Jan 2019 Where would the bottle be needed?

University of Sussex, near Brighton. I think maybe I should just put the effort in to attend a tasting in London, and ask someone to bring in a bottle then...

PhilW wrote: ↑08:57 Thu 17 Jan 2019 So if all goes well, we just have to mount the laser table in some form of portable unit like a backpack with connected hand instrument, and probably wear protective goggles; likely we'd also need a protective suit for health and safety in case of contaminated bottles or breakage. Then we'd be suitably equipped to provide a public service:
"If there's something weird, that's been aged in wood, who ya gonna call?
If the capsule's weird and it don't look good, who ya gonna call?
Level-assessin' makes me feel good!"
Don't cross those beams!

Port Busters (I ain't 'fraid of no corked)

Port Busters (I ain't 'fraid of no corked)

I think you've just earned an opaque bottle..