Heartbeat counter circuit diagram

[aredhel]

heartbeat count

Hi! I hope there is someone who could guide me with my heartbeat monitor project. Well, I've recently finished constructing my hardware and the ECG signal on the oscilloscope was rather OK. The signal was not too noisy unless i move then you could see EMG signal distorting my ECG signal.

Anyway right now I am planning to convert the ECG signal from the op amp output from analogue to digital. After that connect the ECG output to the microphone jack input of my laptop (how am I supposed to do this? Direct connection?).

Using visual basic I will detect the signal coming from the microphone slot and then miraculously write a program to count the number of heart beats. In order to count the number of heartbeats I am planning to find the time interval between the first two "R" peaks and then (60 seconds) ÷ (time interval between two "R" peaks). It is a very rough heartbeat estimation and may not be accurate, but right now I just want to get the gist of programming in Visual Basic.

My main questions are:
1. How do I connect from the hardware circuit to the microphone jack
2. Is it better to convert from analog to digital signal before or after sending ECG signal through the microphone slot
3. How do I detect the microphone slot in Visual Basic
4. In order to count the number of heart beats how am I supposed to do this? Could anyone recommend some good books/websites that I could refer to?

 

[Old Nick]

circuit to count heartbeats

Your microphone i/p (assuming it's a jack socket) will be looking for an analogue voltage.

As for the rest, I have very little knowledge of visual basic so I can't be of more help.

 

[aredhel]

detect heartbeat microcontroller

Your microphone i/p (assuming it's a jack socket) will be looking for an analogue voltage.

As for the rest, I have very little knowledge of visual basic so I can't be of more help.

Thank you for the info. I am wondering about one thing though, could I do analogue to digital conversion through visual basic?

 

[Old Nick]

heart beat counter in visual display

I doubt it.
I reckon what you'll need to do is convert it via an ADC before you connect to you're PC, (unless you wan't to shell out on an ADC card - measurement computing are reasonably cheap!). and then pass it to the PC via USB or the parallel port. I'm not sure what sort of sampling rate you require, or what the max speed of the parallel port is (the parallel port requires the least amount of effort to get working). For USB you'll need to look at some chips to transfer tha data using the correct protocol (cypress make these).

 

[mather]

count incoming pulse from parallel port in vb6

1. The sound card/chip-set in your computer contains an ADC. Google "using sound card as ADC".
2. You could write a VB program to read from the sound card.
3. For the heart beat measurement, you need to use moving averaging to get sensible results. Variations between individual beat is too great to be useful.

Hope this help.

 

[D_A_V_E]

what is the heart beat count

Why dont you use UART?

I can give you the schematic and code for a peak detection(tompkins QRS detect).

let me know

 

[aredhel]

normal heartbeat count

UART? Well I do not really care which method I have to use. Anything is fine with me, anything that enables me to do this within 3 days. Sure the UART thing, it is related to microcontrollers right ... microcontroller things are just lost on me, but I am willing to give it a try!

 

[D_A_V_E]

count pulses sound card visual basic

check you mail

Added after 1 minutes:

If you work with orcad i can send you the original files let me know

 

[aredhel]

make a heart beat use visual basic

Thank you for the help, however I only have PIC16F84A. Can I use what you've given me using that PIC? Another, thing I have my own circuit so there should not be any problem for me to implement the PIC to my own circuit right?

 

[D_A_V_E]

matlab ecg beat calculation from sound card

Should not be a big problem for any microcontroller

 

[ronydc]

heart beats hardware vb.net

DEAR FRIENDS,

Sence the signal with a LDR and an LED and use proper amplifier and filter circuit to produce the niddle pulse. each time the heart beat.
after proper wave shaping the microcontroller can count those pulses with a formula for the count in 1 min. and display it on 7-seg or LCD.

THIS IS THE TOTAL IEDA TO CONSTRUCT A MCU BASED HEART BEAT COUNTER.

REGARDS,

-- RONY.

 

[ifithegr8]

heart beat counts

Yep but can u suggest me a proper amp schematic?

 

[eng_shady00]

usb heartbeat counter

aredhel,
Did u solve ur problem or not?
I think it was from a long time?
but if u still wanna answers about ADC with sound card, i can help u....

 

[aredhel]

how do send beats to the parallel port

Yeah sure. I am still figuring out how to program Visual Basic to access the soundcard and use it as ADC.

 

[eng_shady00]

count heartbeat

But i can do this with matlab not visual basic

 

[aredhel]

heartbeat wav matlab

matlab would be ok too

 

[eng_shady00]

visual basic heartbeat

First u must learn to use daq toolbox in matlab.
Data Aquisition Toolbox.
See this attachment, it's so good.
I've learned this subject from this book, while i had no previous idea about it.
U can search over the internet for other pdf's, u'll find alot.
Also the matlab help is very useful.
Good luck.

 

[logicon]

ecg basic wave shaping circuits

If you can feed ur amplified signal to a digital inverter, you get pulses you can work with. Its that simple for your microcontroller to take it from there. Hope this helps.

 

[akss_here]

beat counter visual basic microphone

using matlab seems easier to everyone, because it have some built-in functions
for scope..
but you won't have to worry if you have little idea about how to communicate between visual c and matlab... i,e more easier to develope..

acquring of signals will be easier in both cases...

there is some difference in handling analog and digital data....