Project for Handicapped Help Needed COPD

Velroc

Hi All,

I haven't been very active with Stamp Projects lately, but have done quite a few in the past, so I know the basic's.

I want to build a device to help my brother who has COPD and is waiting for a lung transplant.· It would allow him to measure the amount and speed of air he can exhale in say 10 seconds. He needs to do this to exercise his lungs,or whats left of them.

I'm not shooting for a imperial measurment, just comparitive from one event to the next.· I want to display a graph on a computer screen of Time vs Energy, the energy being a small pinwheel fan attached to very small DC Generator set up in a tube, maybe one inch in diameter.· Sort of like a wind speed indicator.

The whole idea is that he would push a button and then exhale into a tube and then watch the screen showing how hard and long he's exhaling. Then it would·shut down after 10 seconds or so and be ready for next event or exhale.· This would give hime some incentive to do better if he could watch it on the screen and make sure he was working hard.

If anyone has seel somthing similar or a program that allows graphing on a computer of millivolts vs time I would appreicate some help or point me to a similar project or web site.

Now to dig out my hobbie box with all my old stamps, wires and circuit boards..

Thanks Very Much,
Velroc

andreas6583

Hi Velroc,

I have done something like that a couple of years ago and it worked quite well. My dad had an aneurism on his aorta and had to train his lungs after the OP...

I simply took a strong balloon (not on of these they have for kids birthdays), applied a tube to it as a mouth piece and in that tube I used a pressure sensor (I can´t remember what model exactly) which I linked to a standard A/D-converter...

Since the pressure is quite a constant value within an enclosed space (such as a ballon when blown up) I could give a fair display on what pressure my father´s lungs could produce...

Once he got along with his training and the balloon offered too little resistance, I just aplied another over the first (using some liquid soap in between) and had (a bit more than) doubled the resistance.

I worked quite well because my dad took real pride in blowing the LED-bar·I linked to·the A/D to max...

So·all it took was a short piece of tube (inner diameter ~2cm, lenght about 10cm), a number of high quality balloons, a pressure sensor with a range up to 4 or 5 atm, a simple A/D, and -if you want to use it- a simple design to read the A/D with a Basic Stamp...

I hope this idea can help you !!!
All the best to you brother !!

Andreas

andreas6583

P.S. you can use the BS as an interface to the PC and use some standard graphing software to display the curves. I did not do that back then, but I think there are some freeware graphing tools that can read data from a serial port... I know that a software named mathcad can do that, but that is quite expensive... ;-)

Bean

Velcor,

The SX-Video module might work for you as a display. It's low resolution (32h x 12v) for graphics, but might be enough for your use. It provides video and sound output that you can connect to a TV's RCA Jacks (Yellow and White).

Or you could get fancy and use the OSD (overlay) module and your brother could use it while watching TV. No sound on the overlay module though, but it does have higher resolution for graphics (48h x 16v)

If cost is an issue, send me a private message (PM).

Bean.

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"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012

"SX-Video OSD module" Now available from Parallax for only·$49.95
http://www.parallax.com/detail.asp?product_id=30015

Product web site: www.sxvm.com

"I hope the goonwave is not vaporware"
·

Paul Baker

How about using a stretch of tubing and a clear flow meter, you could attach a ir LED and phototransistor/photodiode to it to count the paddles as they spin. By knowing time and the count both rate and volume could be calculated by knowing how much air occupies one paddle wedge in the flow meter.

<edit> This is what I thinking of: http://www.smallparts.com/products/storagesolutions/scienceware/flowind.cfm·</edit>

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·1+1=10

Post Edited (Paul Baker) : 12/29/2005 5:22:07 PM GMT

AiR_GuNNeR

Two other approaches would be a pitot tube that measures the difference in static and dynamic pressures, or a thermister.

Regards,
Eric Sanders
http://www.compufoil.com

steve_b

What are you measuring? Force? or speed?...volume? Or do you want sufficient backpressure to give the lungs a workout, rather then the lungs just expelling all their air with no real resistance?!

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Steve

"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

Bruce Bates

Velroc -

Here is the answer I got from a friend of mine who has COPD, and is a health physicist besides. Additionally he has a background with the PBASIC Stamp and analog and digital electonics.

quote

There are gizmos available for ten bucks at drugstores that do this very well. They even have a little resettable pointer that shows the max flow rate for the exhalation.

The simplest thing I can think of for a Stamp would be one of those piezo pressure sensors available from Parallax. If the guy puts it into a chamber with a known area exit hole, he could at once calculate flow rate, max flow, and exhalation pressure from one measurement.

That's how the pros do it. Calibrating the pinwheel idea would be hard. Calibrating the pressure vs. known area hole would be easy, even for a Stamp.

If he just wants a graph, he could take the breath (pressure) data and RS-232 it from the Stamp to any one of the freeware logging multimeter programs like I use.

end qoute

If you need the specific formulas, I'll be happy to ask for them all. I only note additionally that StampPlot Lite (FREE!) is also available for RS-232 driven graphing:
http://www.parallax.com/html_pages/downloads/software/stamp_plot_pro_info.asp

Regards,

Bruce Bates

Velroc

Thanks to all for the replies as they have given me some new ideas and cleared my thinking on how to do this..

I don't want to measure flow, I want to graphically repersent pressure vs time.

The person would blow into a hose connected to tank (air tight plastic box), the tank would have a valve (hole) that you could vary the opening so when you blow (exhale) into it you would build up a slight back pressure.

This would give the lung some resistance blow against. now to figure out what back pressure a normal could create ?

So it looks like I need a pressure sensor that I could mount in the box, I found on the internet maximum lung presure is 74mm HG or 1.5 psi, so to safe a 2 psi sensor should do it.

Now to find a sensor with a dc out put and graphing program ?

BTW, he has a mechcanical device called "expand-a-lung" http://www.expand-a-lung.com/ that he uses now, but it gives no feed back and is very boring to use.

Thanks,
Velroc

Steel

Hey...coming at you from medical device field...

There are ETCO2·companies that develop OEM technologies for this sort of thing.· You may want to check into a company called Welch Allyn (http://www.oem.welchallyn.com/pdfs/104410_LC101.pdf) and also Oridian (http://www.oridion.com/english/capnography/products/filterline_circuits_adapters/index.html)

These modules output a UART Data Stream.· You can actually bypass a BS2 by making a UART-RS232 Level converter and streaming it directly into the PC.· Or you can use the BS2 to be the 'traffic officer' to the data.

This may save you a great deal of time in implementation.· Granted, they cost money...but it's your call as to what is most important to you.

·

steve_b

Doing the total MacGyver method....take a piece of hose and attach a condom (non lubed...ribbed for eveyone's pleasure) to one end.
Enclose the 'SAFE' end in some sort of box with a flexiforce sensor attached to one wall (preferably the back one -- furthest away from the hose).
As the person blows, the condom will expand and push against the sensor. The box will provide directional control over the 'rubber' and allow it to push against the force sensor.

RCTime on the stamp should be able to read it in....or use an A/D.

Something other than a condom would be needed to increase the resistance....work your way up to a hotwater bottle.

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Steve

"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."