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BreathUp, good and bad news

Hi everyone!

During the end of the week, I knew lots of emotions. Indeed, Friday, after some tests with lots of noise, I was lost and I did not understand why there was that noise. So, I took the user guide of the tests board and I checked all the default parameters to know if the configuration of the software was wrong or not. After that, I debated with Alexandre to find the reason of this noise but we did not find. With Samuel and Alexis, we tried to watch an electrode signal on an oscilloscope but we watched a noise of 50 Hz too. Alexis or Samuel, I did not remember, tell me to put a square signal in input of the board. So, Saturday, I put a square wave on the board and I watch the wave but there was a noise of 50 Hz again. At that moment, I thought we did never find a solution for that noise.

However, with my team-mates, we met Laurent. He brought us the cable for the electrodes. And with it, he showed us how make an ECG measurement. Laurent said us that we could watch EGC’s picks on the signal. But there were lots of noise. During a debate with Laurent and Alexandre, Alexandre had the idea that the power supply of the board could generate the noise. Indeed, in the user guide, there was a topic which said a supply with stack could reduce the noise. That is why I went to the robotic club to ask them if they had a pin and a box for stacks. Thanks to Telecom Robotics, we could have a new supply with stacks. We also discovered if the computer, which make the acquisition, was in charge there are a 50 Hz noise too. After, that problem was resolved, with Alexandre, we make some tests to have a good ECG with all the electrodes. I assisted Alexandre to reduce the number of electrodes used to have an ECG.

My main task is still to have an EMG (electromyography) to valid the ADC. This EMG will be valided by Laurent.

As I have already told in an old post, today, we have a the PSSC for this task. So we does not respect it and we are in late. I hope to valid this PSSC in the next days.

Bye,

 Benoît

BreathUp, I’m alive!

For today the group was supposed to validate the ADC choice for the EMG, and succeed in using the algorithm given by the startup we are working with. Unfortunately it will not be done for tonight.

However like I said in my previous post, step by step we are going forward! With Benoit and with the help of Laurent we had seen that 50Hz noise was there every time, even on a signal of a wave generator (idea of our instructors). At this moment I knew what the main issue was: The only fact to plug our acquisition card on the 50Hz is killing the EMG signal. Even worth, when the computer is no longer working on the battery, the noise is going throw the usb cable. It’s mean none thing: my working time is as long as my battery charge :). (By the way, my hearth is working very well, I am alive!) Then we start to reduce the number of electrodes, it was working quite well, until the moment the battery of my computer was over.

What’s more the algorithm given by I-respi is not as operational as they pretended. Benjamin and Xavier improved it, but not enough. Like Benoit and me, they should finish it by the next two days, and test it on the acquisition we will have done.

The main goal for now it is having the result we hoped for today with the ADC in the next two days. Hopefully I think the next thing we had planned, should not be impacted al lot (like the components choice and the drawing pcb, which is by the way something we had just done in class by Friday)

See you on Wednesday, and I hope I’ll give you great news!