Device for measuring the exhale of vapour, while "vaping".

Hello.

I have for the past month ditched all tobacco products and instead have immersed my self in the hobby of vaping(which I would strongly encourage any smokers/tobacco users out there to try, seriously it's great if you are using tobacco, want to eliminate the health threats but don't want to quit nicotine), anyway I have a idea for a device which I am still not convinced is possible for me to build.

The reasons why I want to do the following can be debated but the one motivation I am acting on is simply "because I want to", what I want to do is to build some kind of device which I can exhale through and as a result get some quantifying value of how much vapour I exhaled.

Now that quantifying value doesn't need to be an absolute value, sure it would be great if I could design such a device with the appropriate calibration but that isn't likely to happen since I don't have the resources to calibrate it(if it is possible to do such accurate measurements in the first place).

But I have thought that perhaps I could use tube with an approximate diameter of 4cm, and in one or more positions along the length of the tube/pipe place IR-LEDs & IR-transistors opposite to each other and then monitor the amount of light getting through, so if all the light is getting through no vapour is present and the less light is getting through the more vapour is present.

Since I am only really interested in relative measurements that might work.

I'm sure most of you if not all have seen those "wind-meters", I don't know what they are actually called but they look like a little DVM with a extension on the top that goes to a propeller that is surrounded by a plastic wall, or the propeller is more integrated into the device, in ether way the propeller starts turning faster as more air is moving through it. And I would guess that they use a rotary encoder to measure the speed of rotation and if they know the resistance the propeller for the air, or in other words the force needed to start it to move then you probably could make accurate measurements.
I'm sure I'm wrong in a multitude of ways but generally I think that is how those meters work.

I'd love to hear from someone who actually knows.

In any case, I thought that I could mount some kind of propeller in the end of the tube and if I can ether attach a magnet(s) on the outer edge of the blade(s) I could use a hall-effect IC to record the rotation/speed of rotation.
Alternatively use a rotary encoder but that appears much harder to make DIY.
I'm not sure if this would be enough to estimate a air volume?

If I assume that the ideas above could be made to work or that someone have any idea to accomplish those two task, the 2 task being:

• Measure the amount of air travelling through the pipe.
• Estimate the amount of vapour in 1 or more positions along the pipe.

I am hoping that someone might have some thought about this.

Regardings

Congratulations for stopping smoking. I also stopped smoking years ago and a few years ago I stopped alcohol. Now I feel young again.

I have seen people who are vaping completely disappear in their huge cloud of vapour. Then I guess hardly any of it is used to "fix" their addiction to nicotine.
If a person who is vaping is going to walk past me then I look to see if there is something that might hit me (a bicycle?) or I might walk into when I am in his huge stinking cloud of vapour.
I laugh when I see videos of vaping people with their pants on fire.
Sorry, but I think people who are smoking or vaping should have their own island to do it on where there are no normal people to be bothered by it.

I can understand how you feel, I always take care to respect others while vaping, the majority of my vaping is done inside my own home and while being outside(outdoors and indoors) I often resort to snus, a traditional Swedish tobacco product which is put under ones lip(there have been studies but no one have thus far been able to prove any real harm from snus, anyone can understand that it would be more healthy not to use it but it is nothing compared to smoking). So that doesn't bother anyone.

One great aspect of vaping is that a lot of people do start of at a higher nicotine level but then as time passes drop to a very low level and in many cases a zero nicotine level.

I like vaping outside(especially while walking night time which I feel is a good time to vape outside as no one else is out) but I can still appreciate that I like it but others might not, I don't know any one other than my self how are vaping but I sometimes get an impression that there are a lot of vapers who act like jerks and vape anywhere anytime. But I think it isn't more than a respectful behaviour to ensure that you don't vape where anyone you don't know and know are okey with it can come in contact with the vapour or smell, sometimes I vape while waiting for the bus but if so I do it at least 20meters away from anyone and only if the wind isn't going in the wrong direction.
Also I can't help but to react to children, if I sit somewhere vaping and see a child approaching I will not take another hit until the child is out of site no matter if the kid will come close to me or not, children are after all highly susceptible to the actions of elders(older people, not specifically old and wiser people)

These are things I think anyone conducting such practises as smoking/vaping should consider. Sure I should be free to do act and do what I choose to as long as my actions isn't affecting someone else, I have meet many smokers whom feel that people whom are concerned with second hand smoking are silly, but I don't see it matter how tiny or insignificant the affects are(I'm not saying that they are insignificant) I see it as perfectly reasonable to mind if one is inhaling toxins due to some one whom one doesn't even know have chosen to go berserk at there lungs with tar and doesn't have the thoughtfulness to think about not exposing others to it. And the health aspect isn't necessary relevant, if we where living in a world where smoking was completely harmless it still would be offensive to expose others to the smoke. That is how I see it anyway.

If one is conducting there vaping in a manner such a this I don't really see that an island is necessary, obviously not everyone does it like this.

But if they where, would you still feel that way?

At the doctor's I was given a spirometer test. It's an instrument which measures how strongly and how much breath my lungs exhale.

Evidently it is capable of measuring very soft breathing. I don't know what type of mechanical device could spin, or bend, or whatever, so as to be that sensitive. (It might be non-mechanical.) The spirometer is about as large as my internet modem. I held it to my mouth and exhaled strongly. It gave no resistance to my breathing.

We used small spirometers in biomedical Eng. lab. They use a spiral turbine blade and IR photo interruptor to measure RPM which is linear to flow in that design.

Re: Device for measuring the exhale of vapour, while "vaping".

I will look into spirometers, but it at least sounds as if I where to design the space that the air/vapour is to travel through correctly then a turbine blade who's RPM is measured by some means would/could display a linear relationship between RPM and the flow of air.

I guess that would be half the design, so figuring out such a device is a good start.
Let's assume I had built a device which measures the flow of air, then I could incorporate some kind of sensing related to particles.
I think a IR LED or some kind of LED sounds good, oh no...

I just tried something, I friend gave me a "Laser 301" laser pointer which supposedly is a green 532nm 5mW laser. But I suspect it is a fake in some manner, because while it is very powerful and can shine incredibly long distances it can't, not even if lit for hours light a match as the add pictures on Ebay and such show it doing.

In any case, I inhaled from my RDA(Rebuildable Dripping Atomizer, a device for vaping) and then activated the green laser and directed it towards my wall 3 meters away, then I exhaled in the direction of the laser beam and for a second or more the green dot disappeared completely...

I am hoping that it is not fully true and that it only disappeared from the sight of my eye's and that a IR or some other source of light can shine through...
But I haven't a clue about if that's possible at all, it is possible that the exhaled vapour cloud did to 100% block the laser.
If that is true that would scrap the hole concept of measuring air flow and with a measurement of time calculate the volume of air, together with a IR transmitter/receiver that can in some manner quantify how thick the vapour is by judging to what extent the light received from the transmitter is blocked.

Before I ask I want to remind you that the aim of the following question don't have to be considered viable in a usage where the results has to be very accurate nor related to some calibrated value, I only want to compare one thickness of vapour to another, and another, and another etc.

Can you think of any way of doing that?
Is there some wavelength more likely to be able to cut through the vapour or is something that blocks light of 532nm going to block all kinds of light?

Maybe I could construct some kind of capacitive sensor, because imagine that I had two plates isolated by air. If I then monitored the capacitance while blowing a thick vapour on the sensor filling that air-gap with a lot of vapour, could that be enough to indicate a change in capacitance... What do you think?

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Or could a humidity sensor perform with enough resolution to manage this task?
I understand that you probably can't answer these questions absolutely but I am just as interested in your opinion/estimation or simply your guesses as any other answer.

Re: Device for measuring the **density of particles** , while vaping

You should have no problem getting a signal with transmission loss in a tube with a green laser and a Panasonic buffered optical Light Sensor which supports more than 4 decades of range with 5Vin and a DMM on the output and you choose the load R for the max output signal.

The lungs will generate more moisture than the vaping.

HINT
search key words
panasonic 5mm light sensor digikey

Generally Vaping is converting a liquid into micron sized smoke particles and you want to count them by average transmission loss.
You can use a RED Laser too.

2nd HINT
search key words
laser particle counter design

Re: Device for measuring the exhale of vapour, while "vaping".

David_ said:

turbine blade who's RPM is measured by some means.

Click to expand...

A pinwheel made from thin paper could do this. Set it in a cylindrical cavity so that it spins in response to breath coming from the bottom opening. No bearings, no friction. Measure rps with a photosensor.

Come to think of it, a styrofoam ball is probably all you need. I had a wind meter based on this principle. It rises in a tube, in response to windspeed. The challenge is how to sense its position electronically, of course.

I'm having a hard time picturing exactly how you mean Brad, but I think I will avoid any material which can absorb moisture.
I have thought that I would use a tube which I will refer to as the wind tunnel/tunnel, and mount the blades with three arms such as computer fans are constructed. I had also thought that maybe I can find blades from a small computer style fan, I have quite a few of those, with a diameter around 4cm.
If a sett of blades such as those could do the job then mounting magnets on the outer edge of the blades would be very easy, and all that is needed is magnets strong enough to clearly register on a magnetic sensor positioned on the outside of the tunnel wall which would be something like maybe 4mm away. The wall being around 2mm thick, once I have determined which blades to use I'll go to a store to look for plastic tubes.
Hoping that a air chamber that is simply a peace of plastic tube is going to display a linear relationship between flow and RPM.

I think the paper idea is a good one aside from the fact that there will be so much moisture in the air, I have begun to plan for buying a 3D-printer but that is still some distance into the future.
But it would be cool to design and print the tunnel with the necessary holes for mounting the laser and sensor as well as the armature for the turbine-blades.

Another problem I have, I am having a hard time using the tips from post #7 by SunnySkyguy.
I started searching for suggested search terms and found my self quickly getting to know that these kinds of sensors are made for a particular wave-length and as such I stopped looking at sensors and started to look for a laser, first I checked out laser diodes at mouser(my favourite is digikey but as I live in Europe it is not viable due to the extra cost it brings) but the cost of laser diodes like that is not an option.
So it's probably Ebay that is the solution, but I know so little about lasers.
Is it acceptable to use a ordinary laser pointer such as this laser pointer module?

There are also laser modules such as **broken link removed** which has TTL Modulation of 0-20khz which I don't even know what it actually means. I of course know of TTL but what is modulation of a laser between 0 and 20kHz...
The duty cycle of that module is specified as: Duty Cycle 45 seconds ON, 15 seconds OFF
There are also **broken link removed** running at 12V that has TTL, and then there is kits which contain driver, laser module & heat sink which appears as overkill in this instance.

But the prices of the products linked to are quite a bit higher than what the most basic green laser pointer module costs, and if 0-20kHz modulation is useful... I am probably the worst person to be expressing any thoughts about this as I really don't know anything at all but I can't imagine why modulation would be good for...

In any case, those laser pointer modules could easily be incorporated into my design by solder off that push-button that is used to activate the laser and replace that with a transistor controlled by the microcontroller controlling the apparatus.

Re: Device for measuring the exhale of smoke, while vaping

Laser Particle counters are expensive items that use a constant flow rate and a constant shear air flow to deflect particles to a linear detector which uses a thin tube to measure particle counts for each mass due to deflection which translates to size.

The number of particles per cu. ft is always inverse to size in a 16 bin histogram but cigarette particles are typically largest and they are calibrated with a certain latex powder.

COunts in a home (/cu.ft) are typically 100k and go over a million in a dusty environment while 10k HEPA is filtered air and 100 is a clean room with high air recycling thru HEPA filters and air showers on entrances.

To measure particle counts is a difficult job with just a transmission mean sampling the air flow but can be ok for a relative measure. First a flow rate would be accumulating counts where the transmission signal drops below a threshold or perhaps is reflected by scattering in a non-reflective black tube.

Then particle density is accumulated loss (integrated) and total particles is the density divided by volume flow independent of velocity.

So one would need to split the beam to detect RPM and count revs then measure change in PD level for density of particles to get an approximate measure of white particles. You can't count each one with a 1mm beam as the particles are ~ 1 µm in diam. (EST.)

The turbine blade must fill the tube with minimal Mass or friction loss with good sleeve bearing and balance. The spiral shape enables capturing all the flow with minimal bypass and load pressure.

This is just food for thought, but you could try laser pointers and those used in mice to see what analog response you get with a tube past the lens.

I had one laser mouse that could detect a finger wiggle at 1 meter on beam axis from from bottom by trial and error, to detect going out of sleep mode and turn on both IR and visible LED. Some use blue.

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TTL (logic) is pulse On probably with active low On at ~1mA . up to 25kHz.

Internally there will be a Constant current source.

My description of the pinwheel was half baked. It needs a center pivot of course. A pin through its center is adequate for mounting.

As an alternate consider a simple swinging vane in a tube. A photosensor can detect its position. Response may not be linear but its ease of construction is hard to beat.

Thanks for the thoughts, I have been reading a document covering the basics of particle counters and after a few hours of reading I am no where near any chapter even mentioning electronics. I have read about particle size estimations and standards for different ranges of particle sizes and etc etc etc.

But I think I never should have used the term "particle counter", if I have done so and if I would to use that term again in relation to this project don't read that as if I am actually talking about counting particles. I did understand that to actually measure particles I would have to invest large sums of money and a lot of time, probably years. But what I am trying to do is rather to estimate particle counts above millions of particles.

Saying > millions is even a random guess as I have no clue about how many particles there might be in a quite thick cloud of smoke, I thought that e-cigarettes produced vapour but that doesn't seem to be the case. I know that one of the main components in e-liquid has for a long time been a primary component in the liquid used by smoke machines, some earlier in this thread wrote that my lungs will generate more vapour or moisture than what my e-cigarette will generate.

In any case I now am more interested in Brads idea than I was before as I should build a as simple device as possible to find out if what I want to do is even possible, that is estimating the amount of smoke in an exhale. How that would be quantified wouldn't necessarily be expressed as particle count as that is something I will never be able to more than make wild guesses so I will probably be displaying the result as a analog voltage response from the light sensor rather than to convert that into something else since whatever I would convert the voltage into would be nonsense anyway.

Maybe I'll use an imaginary unit akin to wattage or power since I will have a varying voltage and a unit for the exhaled volume of air maybe I could multiply those numbers into my own new vape unit...

I have a couple of questions though, lets assume I have a plastic tube with a diameter of 3cm that I am going to exhale through and that has a turbine blade of some kind at the end of it to estimate the volume by measuring the time span of the exhale and the RPM of the turbine blades.
I will design my own constant current driver for the laser but I'll probably will buy a few cheap laser pointers on Ebay and use those diodes in my own driver since I think it would be rather stupid to relay on the design in those pointers.

So now we assume that I also have a adjustable constant current laser driver with a green(or red) laser diode, that delivers current with little noise and very stable amplitudes.

I haven't figured out what kind of sensor I should use jet but I will start from the tips SunnySkyguy posted, but assume I have found a light sensor which is sensitive to the appropriate wave-length.

1.
Mounting the laser and sensor at opposite sides of the tube did sound good to me before, but now I wonder if it might be better to construct some inner structure in the 3cm tube in order to close the gap between the laser and the sensor.

What do you think about that?

2a.
Also do you think I should acquire a lens to focus the beam from a laser pointer laser diode?

2b.
Is focusing a laser beam in this situation with a lens that redirects the beam into a narrower width much different from simply blocking out parts of the beam to only let a smaller area of the beam through?

3a.
I get that I could vary the intensity of the laser beam by varying the current in the CC-laser-driver but what effect could that have on this situation, would a higher intensity beam be able to push more light through to the other side when the gap between the laser and sensor is filled with smoke?

3b.
I guess at some point the laser beam would start to destroy the smoke particles, and sooner or later the sensor would go up in smoke as well.
I hope there is a big difference between the power levels needed to shine a green laser and actually doing things like igniting small amounts of wood or paper...

Regards