Capacitive Sensor Array Switch

I'm looking to build a on/off switch using an array of capacitive sensors.  To turn the switch on requires a finger swipe in one direction, and off in the opposite.  I will be using an Arduino with capsense as the controller.  

How can I detect which direction a finger is moving across the array?  I understand what needs to happen and would research it myself if i knew the terminology behind it.  



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fmoreno22 years ago

I think I've done what you are (were) searching for. If you need more info about this or would like to explain how you have solved it I would very much like to talk about it!

Attached is a pic of my breadboard and the copper rings that act as touch sensors

2015-06-12 16.47.58.jpg
when you touch the array it detects where your finger is at on an x,y grid. So to detect a swipe up the controller needs to see the x value go from ant lower value to a higher value. So of the number being reported to the controller you need to work out which is the x and which is the y.
buckchuck27 (author)  mpilchfamily5 years ago
I'm just using a 1D array of sensors. Essentially what I'll need is to calculate a gradient throughout the sensors. Would it be easier to just measure which sensor has the highest output and compare that over time? Or calculate the change in difference between each?
What format of data do you get from the sensor when its scanned ?
buckchuck27 (author)  steveastrouk5 years ago
Its going to be an analog input into an arduino. The sensors are goin to most likely be copper pads connected to the arduino with a small cap to reduce noise.
So you read "the pad" and get a single number back each time you read it ?
You'll presumably get a string of numbers back from the sensor as you scan it. Those numbers will, increase and decrease with time. Take a reading now. Wait. Take another reading. Is the new reading bigger or smaller than the old one. If its bigger, your sensor output is increasing, if less, its decreasing.
If it could be done like encoders 90 deg out then you would know witch way witch.