Week 8 Update

This has been a great week in terms of progress for the group. We tested the electrodes in lab on the oscilloscope and the readings were perfectly sinusoidal. It was one of the only amplifiers in the class that actually worked exceptionally well. Although we found out that we made a mistake when building the amplifier circuit. We didn't realize that when the product description said that the amplifier integrated circuit contained two amplifiers it meant it could handle four electrodes while we are only using two. What this means is that we built twice as much as we actually needed. In reality this isn't completely bad since we would have had another way to test the electrodes if one side didn't work. We also started testing the electrodes using the mask, which worked surprisingly well without any of the modifications made yet. The mask helped to keep the electrodes in place even when there were alligator clips connected to them. As the week progresses we will be testing the accelerometer and electrodes together.

This video shows what the electrode signal looks like when connected to the oscilloscope. This test was conducted with one electrode next to each eye.

This is what it looks like when the electrodes are connected. We later found out that we only need one alligator clip on each side instead of two. 

Week 7 Update

This week has been extremely productive for us as we have gotten the mask in and started testing everything. We focused on the accelerometer first, Michael has finished the test program for the accelerometer while Alex and Julian made the wristband to hold the accelerometer. Julian has also downloaded the top rated accelerometer app on his iPhone in order to test both the accelerometer app and our device at the same time. In class we were able to test the to see if the amplifier worked, and to our surprise we found out that we didn't burn out the amplifier while building it. We were able to use an Oscilloscope to see the readings from test electrodes placed on Julian. In the coming week we are going to fabricate the mask and learn how to interface the electrodes with MATLAB in order to test the entire device at once.

The accelerometer wristband. 

An idea we were toying around with for the future. To attach the Data Acquisition Unit to the user with either its own wristband or with the accelerometer.

Julian and I testing the amplifier and electrodes. 

Week 6 - Update 2

We've spent a lot of the week thinking about how we want the output to look. As you can see in our previous post we have made a flowchart of how we think that we want the data to be logged and processed. This flowchart is just a preliminary one so it doesn't go into any detail about how the program itself will work. We also spent time this week comparing other programs that use an accelerometer to track sleep to see how accurate they really can be.
In other news we have been thinking about how we should attach the accelerometer to the person that is sleeping and have come up with the idea to make a wristband with a small pouch that can hold the device. The wristbands were actually delivered already so now we just need to cut up one of them and sew it to the other to make a pouch. Also, the EOG sensors have finally arrived! We are excited to start testing them to see how they work and how we can implement them.

The two wristbands to hold the accelerometer in place.

99 EOG sensors, we tried one on to see how it feels. 

Week 6 - Update 1

The preliminary flowchart on how we want the program to output data. 

We have made an initial flowchart of how the data will be collected. I figured it would be good to put our thought process at the moment on paper.

Week 5 Update

We have encountered two problems over the past week, but we are still on schedule for the most part.  The first problem we have run into is that the mask has been delivered for over a week now but we haven't gotten an email telling us to pick up our package. The second problem we have run into is that the electrodes never actually shipped. We called them up a few days ago wondering where the package was only to find out that they never shipped it by accident. They said that they would ship them overnight, so we should receive them soon. Schedule wise we are actually exactly where we want to be. We will be done with the electronic section this week and we will start on the mask portion this week.

Even with these problems we have still accomplished. We have made all the alligator clips necessary for the project, we have grounded the entire circuit, and we are still working on the code that ties everything together. We have the accelerometer working in MatLab, yet we are trying to filter it to get it to be more accurate than it is right now. We hope that by the end of Week 6 the accelerometer can be finished and be ready for testing while we put together the EOG portion of the circuit.

Now that all the parts have been delivered I can give a breakdown of how much we spent on the entire project.

• Electrodes - $15
• Mask - $10
• Circuit board - $5
• Batteries - $10
• Amplifiers - $10
• Wire/Alligator Clips/Resistors/Capacitors - Free
• Total - $50