Re: WAV file for arterial blood pressure? (for simulator)

What software do you use to capture those clicks? It would have to be a sort of semi-see-through overlay or I'd have to somehow print on vellum and tape it to the monitor.

That sounds tedious, especially for a length strip recorder plot.

As it's easiest for me (familiarity), I'd just load it into AutoCAD and then just place "points" on it -- and extract their coordinates from the file after closing/exiting. I suspect you could do similarly with anything that has a GUI i/f and some notion of "coordinates" (e.g., a PCB layout tool with a fine grid -- relative to the scale you are viewing at).

You may even be able to do it with a WAV editor (?)

In my case, it was very efficient. And, gave me the data in the form that was most useful to me (i.e., *as* bezier control points and not an endless stream of (x,y)'s)

Note that you want that graph from "wherever" *you* will expect to be "encountering" (i.e., measuring) it. Location on the body (as well as the body's "orientation") makes a difference.

Unless you're looking for a sensor as *crude* as the consumer BP cuffs...

Essentially aortic pressure. That's a standard proceduce in medical, during the more serious activities such as coronary vessel intervention. Like a monitoring. Right now the exact form and fidelity of the signal doesn't matter much which is why it does not even have to be from a human. Right now all I want to do it experiment with the simulator and my circuitry.

The only software like that I have is a rather crude arb function plotter for a Chinese function generator. It generates ASCII. That'll be a pain. WAV generator software like Audacity doesn't allow hand input but maybe some others do.

I believe LTSpice only takes WAV. But I'll get there, somehow. It's not super high priority but it would be nice to be able to feed the real McCoy into a virtual circuit.

extremely simple is something like octave:

x= [ .1 .2 .3 .4 .6 .7 ]; % vector of your numbers wavwrite(x,8000,16,'filename.wav'); % save vector as 16bit,8kHz wav file

-Lasse

LTspice gives, or takes, .wav files. It's oneway to make 'uniform' steps

Recent discussion on the group WITH Helmut posting examplesof how to do.

If one "typical" cycle, repeated ad infinitum, would work, then you only have to do the tedious part once.

Any drawing program that (a) lets you use an overlay, and (b) lets you make a line from an arbitrary set of points, and (c) has a semi-human- readable format, should let you do this. Once you get the points, then you can use something like Scilab to generate the wav file.

(You don't seem to sublet work -- but if you did, and you wanted me to, I could take a picture and make you a wav file. Probably other people could, too. If you've got a software person on board, s/he may be able to do it, for that matter.)

Oh, I do sublet work. For example, all the software stuff is done by a SW engineer about 4 miles from here. Well, 7-8 miles per mountain bike. All my layouts are also done but contractors, mostly the same one down near 65th Street in Sarcamento.

Thing is, I don't have a suitable curve yet. Also, it's typically not a constant curve but there are changes as the heart gets stressed, pathological events happen, and so on.

I use a Java-based graph slurping program called DataThief. Works OK, but it's one of those idiosyncratic Euro-type things. ;)

Cheers

Phil Hobbs

On a sunny day (14 Mar 2015 23:20:26 GMT) it happened Jasen Betts wrote in :

Wrong, although it is true watyousay, I had a lok wit hte hex editor and was no problem to derive teh graph. But it does help I wrote some mouse drivers...

That is very nice indeed.

We don't need that complicated stuff.

But just sticking milimeter paper on the screen and copying the graph, gives you a change to write down the numbers too.

And you only need one period, and that repeat that endlessly for the wave file.

qwkastaio :-)