GMU:Autonomous-Collaborative/Ludwig

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Fiddleing Surface

Concept

 
the fiddleing surface with an pointing device out of metal

The in 2016 upcoming Fidget Cube is a device that supports different tangible areas.The idea of adding an additional audible level led me to a design that I call "Fiddleing Surface". It consists of different tactile media which are connected by a wooden frame. The pickup is fixed to the wooden frame and connected to a Raspberry hidden by the construction. A special PD-Patch is running on the Raspberry to apply interisting filters to the output of the piezo microphone. With earphones plugged in tothe raspberry, the user can now hear his touches.

Construction

My goal was to use many different accustic materials. I started with a wooden frame which surrounds an inner base plate. I divided the plate into two halves, one with acoustic foam and the other with lines and circles engraved. On the front side I attached a wire frame and connected it loosely to the body. Furthermore, I have plastic hair of a broom built into the frame. The piezo microphone is glued to the base plate. Below it are the audio interface, a small power bench and the Raspberry PI, which are mounted on the feet. They are hidden by the frame. It is important to place damping bouncers under the feet. This prevents the transmission of foreign vibrations to the microphone.

For the audio processing I combined different effects and filters. I used

  1. sine pitch
  2. low and high pass filter
  3. reverb (echo)

Implementation in Pure Data

 

My sketch consists out of a main sketch that is directing several subpatches. Therefore new effects can be easily added to the program.

control of channels

 

Because the experience is more immersive if there is no hard cut between the effects, I decided to implement a control for the channels which allow a fade-in and a fade-out after a change.

sine-pitch

 

For this effect I used the pitch example in the PD-documentation by Miller Puckette. Because I did not wanted to have a static factor for the pitch I uses a sine wave as factor to modulate the input. For every instance pseudo-random growth rate and pitch range are generated.

low and high pass filter

 

reverb

 

Demo

testing the fiddleing surface


Discussion

I wanted to build a device that uses the piezo microphone and a raspberry to create relaxing mood with sounds and tactile media. The result is a first feasible approach. In my opinion listening to the device is surprisingly immersive. But that's a purely subjective assessment. For further improvement, it would be necessary to develop a user study that verifies the benefits. Also the following points should be discussed:

  1. The device is too big and difficult to transport. The sound processing should be optimized to a system on a chip, such that the whole processing could fit in a regular fidget cube.
  2. The audio processing doesn't show the potential yet. There are still too many pseudo-random controlled values. Instead of randomness I would like to use more input signals from the user. I think it would be cool to add harmonics dependend on the orientation of the device, which can be measured by a gyroscope.

Conclusion

Download

You can download here the software for the "fiddleing surface": File:fs_patch.zip