Sunday May 19th 11-16:00 (4h) at KOBAKANT New Studio (Schönwalder Strasse 23, Wedding/Berlin)

Our fingers are constantly swiping across touchpads, to enter passwords, navigate maps, play games, type messages. But how does this work? How are our physical interactions with materials sensed and translated into electronic signals that our computers can understand?

In this workshop we will build our own muti-touch pressure-sensitive touchpads from paper, copper tape and velostat – a carbon impregnated plastic film with piezoresistive properties.
Then we will use the vvvv visual programming environment to read our touchpad’s raw data, apply a blob detection algorithm to detect multiple touch points and do gesture recognition on this input.

When: Sunday May 19th 11-16:00 (4h)
Where: Schönwalder Strasse 23, Wedding/Berlin
Cost: free
Prerequisites: none
Max. Participants: 8

Register by sending an email to hannah@plusea.at
(please mention if you are able to bring a computer running Windows)

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To prepare in advance of workshop:
– If you have a Windows PC (or MAC with Windows install) please bring it (if you don’t have Windows we will pair you up with somebody who does)
– Download and install vvvv which only runs on – download from here: [vvvv](http://vvvv.org/) (link coming soon)
– Download and install arduino – download from here: [arduino](https://www.arduino.cc/en/Main/Software)

If you have any of the following, please bring:
– 3 button mouse
– Arduino

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This is the 3 x 3 paper touchpad you will make in the workshop and learn to build the circuity, program the Arduino and vvvv for.

Photos >> https://www.flickr.com/photos/plusea/albums/72157708415692535

With the same principal you can go on to make larger soft fabric touchpads like this one:
>> https://www.kobakant.at/DIY/?p=7651

And stretchy ones too:
>> http://www.kobakant.at/DIY/?p=7639

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Schedule

PART 1: 11-13:00 (2h)

– touchpad demos
– workshop overview
– Arduino & vvvv install check
– intro to electricity, resistance
– translate resistance to voltage
– intro to Velostat
– build a Velostat potentiometer
– build a Velostat pressure sensor
– build a voltage divider
– select a pull-up resistor value
– microcontroller programming (Arduino)
– analog-digital conversion (ADC)
– internal pull-up resistors
– Velostat matrix (3×3)
– i/o pin reconfiguration in loop
– matrix parsing code (Arduino)
– serial communication

PART 2: 14-16:00 (2h)

– intro to patching with vvvv
– drawing a line with a mouse
– reading serial communication
– gray-scale translation of matrix data
– blob detection
– multi-tracking
– gesture recognition
– gesture training
– (share data in network)

Links
pressure sensor matrix >> https://www.kobakant.at/DIY/?p=7443