WEEK SIX

Bismillahirrahmanirrahim.

My FYP needs me to do both software and hardware development. For hardware development, I had find a circuit that need to-be-construct. I had posted the circuit in previous entry (click here). For software development, I use PIC software. This also I had posted in previous entry (click here) and (here). 

I also need electrodes which are the main components for my circuit construction. There are five total of EOG electrodes needed for this project. Four are placed around the eyes and one more is the reference electrode which place on the forehead of the subject. Reference electrode has a stable and well-known electrode potential. The high stability of the electrode potential is usually reached by suitable redox reaction. Reference electrode is an electrode that maintains a virtually invariant potential under the conditions prevailing in an electrochemical measurement, and that serves to permit the observation, measurement or control of the potential of the indicator or working electrode.

This is the four channel configuration or also known as electrode placement. I use this configuration because this configuration has four direction compared with the two electrode configuration which use only one plane which are right and left. The four channel configuration use two planes which are upward and downward and also right and left. This can be simulated to mouse cursor direction.

 

copied from Google

The voltage range for EOG signals are different and depend on individuals. But the voltage is still in millivolts. So, the circuit need to filter the noise and amplify the small signals from the resting potential of the retina.

Barakallah.