on Kerem's warning about hardware malfunction

1. Checking every cell on the pressure map:

the color mapping shows where each point on the sensor maps to the visual map.
Every cell on the map is read except the last row of the map and one other cell (marked with red crosses). These cells exist on the map but cant be location on the physical sensor.
Sometimes when I pressed a cell, other cells would also record pressure. This happened for 2 cells in particular. But the second time I tested, this effect was gone and every cell that was pressed was read individually.

2. Pins:
the horizontal pins (5 of them) are connected to the "ANALOG IN" part of the arduino from 0 to 4

and the vertical pins(10 of them) are located on the "DIGITAL" section of the arduino starting from pin#22 and only on the even pins, indicated by the black marker below.

About the pins 41,43,45,47,49, there are some wires connected to them. 4 yellow ones and a red one which is connected to pin 41. From the other end, these wires are connected to the white board on column j. Here is a mapping:

pin#    |    board# (column j)

--------------------------------------

41       |             45

43       |             48

45       |             55

47       |             58

49       |             60

The picture below shows the above mapping:

02 July 2013

Collecting Data

I collected data today from 4 subjects at different times of the day. Each person performed every touch pattern two times in non deterministic order.
The contents of each file include :
1. pressure map
2. accelerator data
3. time stamp
4. label
5. x location of the centroid
6. y location of the centroid
7. collection version (1, if the centroid is not included, thus needing post analysis. 2 if the centroid data is included)

May 09 2013

Title: Searching for the source of the noise

1. Thread sewed in the wrong place. 
Today we found out that a single conductive thread was sewed in the wrong place as shown below:

The problem here is that the conductive thread does not have the thin layer of fabric below it and so it always connects the top layer of conductive sensor to the bottom layer. I will fix this issue as soon as I can get some conductive thread.

2. Reversing the 10 pins on the Arduino
I plotted the FFT plots again after reversing these pins. Below are the new FFT plots:
They look a lot more reasonable, with a lot less spikes. We can still see the spikes at 7 Hz and 15.3 Hz in some cells but they are much less than the previous time and with much less power.

(1,1):

(1,2):

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