Category Archives: Updates

First Real Time ECG Sample Acquired into MATlab workspace

Today I was able to acquire a number of my own real time ECG  samples,  filter the   60 Hz power line noise out of the signals by means of the digital Notch Filter C code, launched to OMAP-L138 LCDK, and record the result into MATlab work space using  MATlab DAQ Toolbox.

(Please, click on the picture below to see the enlarged image)

ECG2

 

Being able to record real time ECG signals into MATlab allows us to further process data using MATlab programming tools.  Thus, at this point it has been decided to replace the WinDSK8 software, initially used in the project, with MATlab. The Tutorial about “how to get started with WInDSK8” will still be placed on this website.

Digital Notch filter

Now we have a working digital Notch filter, needed to eliminate the 60Hz Power line interference from an ECG signal. The filter was implemented by  writing a C/C++ code and inserting it into a Code Composer Studio Project. As it has already been mentioned, Code Composer Studio is compatible with TI OMAP-L138 LCDK, so we were able  to load the code to the board and run it. The video, linked below, shows that the filter attenuates the amplitude of the 60Hz input signal while keeping the amplitudes of  other frequencies inputs unchanged.

Digital notch filter demonstration

The Code for the Notch filter will be posted under the “Code examples”  tab on this website.  =)

Some progress regarding Experiment 3.

Using the analog amplifier circuit, built for Experiment 2, we have been able to record an ECG signal on a digital oscilloscope screen.

Capture

After having connected the analog amplifier’s output (pin 6 of the U4 op-amp) to the analog Line  In  input of the OMAP-L138 LCDK board, we were able to obtain a  digital    signal of approximately 1 Hz frequency with clearly distinguishable QRS peaks on a PC screen, using the Oscope/Analizer function of the winDSK8 software. The signal, however, was distorted by  a  60Hz noise, which is to be removed by means of a digital Notch filter.  The results  for  filtered ECG signal, as well as the   lab guide for Experiment 3 will be posted soon.

Our Draft Paper made it to the final round!

This evening, we received the news that our Draft Paper submitted on January 7th, was accepted into the 2014 ASEE Annual Conference! This is an admirable milestone achieved by our research group as we are one step closer to a Final Paper acceptance!

We are now working on the revision for the Final Paper that shall be submitted on the 16th of February. Our research group is working harder than ever before to submit a state-of-the-art paper. We appreciate the support, and will provide project updates on a weekly basis.

A timeline of our paper’s journey:

  • October 20, 2013: Abstract submitted
  • November 5, 2013: Abstract accepted/Call for Draft Paper
  • January 7, 2014: Draft Paper submitted
  • February 4, 2014: Draft Paper accepted/Call for Final Paper
  • February 16, 2014: Deadline for Final Paper submission

Using OMAP L-138 Oscilloscope function

So this morning we accomplished some great things in the project. We were able to acquire some sine waves and voice signals, filter them and see their waveform on the screen of a PC. Very exciting!

We are now working on integrating our ECG signal amplifier with this Oscope function in the OMAP, and we wish to have some real-time ECG processing soon.

Below some of the waveforms registered:

Sine Waves
Sine Waves
My voice signal saying "Biomedical"
My voice waveform when saying “Biomedical”

Our ECG Amplifier works!

Last month an important milestone in this project was achieved! The final ECG circuit was finally assembled, specified, and tested! That was the first time we achieved a real-time ECG signal on the screen of our laboratory’s oscilloscope.

You can check out the video of our first ECG signal here (I apologize for the quality of the video, we did not have a good camera to register this moment).

The tutorial for this accomplishment and the steps to reproduce it are listed here. Please feel free to check it out. Any comments and suggestions are welcomed!