Tuesday 29 January 2013

Great results in the remake of the Pure Data patch for "When the Doorbell Rings".

Pretty good results for the update of the patch as it became much more user friendly.
Also, included a README to the folder so there is a set of instructions for anyone to follow.
As convenient, all the hardware was operational.
The display was already tested in the spacing camera and it proves efficient.
The patch was tested without the arduino connected.
As it is aimed for the piece to be a stand alone artwork without the need of extra dependencies, the system is going to migrate to a raspberry pi running linux.
Pure Data runs on linux, so the r-pi will deal with all the processing needed for video and audio.
In a few words: this piece get to have its own computer.
 

 

Saturday 26 January 2013

Rework to python

Last Saturday I met again with Ricardo Amaro in very fruitfull afternoon towards the making of Cycle Sound.

We spent a lot of time installing libraries and modules and stuff... It pretty time consuming. Anyways, the point being trying to migrate part of the project to python. The language is easier and there is a greater array of possibilities with it than with the Arduino software. Mostly because with the Arduino software we can only work within the Arduino. With python we can work/communicate with Arduino along with being able to control other softwares and/or platforms.

So, towards the programming of Cycle Sound, we got hold of controlling parameters given by Arduino. We are still working our way around the piezoelectric as a sensor. I think we made quite a good progress, however it made me realise that the problems, or most of the problems we are having with the piezoelectric are not from the software domain but rather from the hardware. Electronics!

The information available online of how to go around piezoelectric issues when connecting it to an Arduino is very scarce and hard to find. However I found a great article on it which hopefully is going to get me through the main problem.

The problem is the signal peaks given by the piezoelectric. The point is to make the piezo a clean single "bang" signal containing a value that is to be transformed into midi velocity. There is nothing (or probably not much, very complex and not very effective) that software can do to go around this. So it comes down to a simple small circuit between the output of the piezo and the input of the Arduino. A couple of diodes and an RC are meant to do the job. I haven't fully tested this as I'm still waiting for one of the diodes to be delivered but I have quite high expectations, I must confess.

If the result proves effective, I will be confirming it over here. I will give the different possibilities that I tested and report the best results. I don't have an oscilloscope or anything to measure the signal in a controlled manner, but in the end, it's the results on the project that I'm interested in.

If it all works according to expectation, this is a great step towards any kind of drum machine with a great controll level and sensitivity.

Looking forward to the results!!!

 

Tuesday 22 January 2013

Cycle Sound dataflow diagram

This diagram represents the data flow from its input (the bicycle) to the output (the speakers).