Review of Processing Books

It has been quite quiet here lately. Not because I have abandoned this blog, but because I have spent numerous hours and nights learning to program with  Processing (www.processing.org).

Reason for this has been a project named as UNUI.

 UNUI is an improvisation project by voice/sound artist Aava Uusikuu, visual artist Outi Aho and sound editor Jouni Korhonen. "Unui" is a word of an imaginary ancient language. It is some kind of glossolalia, enjoyable movement of a mouth without closed meaning. Live shows contain visual structures, organic soundscapes and affective human cries, murmurs, mumbling, babbling, singing and speaking weird languages. Each performance is different, because the song, sound and visual elements are generated during the presentation. (https://www.facebook.com/#!/pages/Unui/188416394512662?sk=info)

My role has been to provide the interactive visual improvisation for the presentation.  I have used my drawings, paintings and photographs as the source of visual material. During the show, this material is animated, combined and manipulated both by the computer (based on the improvised sound)  and by myself .

I wanted to program the software by myself.  I selected Processing, because I already knew some basics of it due to fact that it is used in conjunction with arduino. I did study other possibilites also (such as PureData and VVV) but I decided to use processing because I already have some basic knowledge of C and C++ .Otherwise I didn´t knew anything about graphical capabilities of the Processing or Java.  

As an incurable book-a-holic. I decided to buy several Processing books to support my learning path. Actually I bought four of them. I do not regret buying any of those because all of the have special unique merits. Below some of my feelings related to those books.

Getting Started with Processing, Casey Reas & Ben Fry, 2010

This small booklet (194 pages) is a good and a very quick starting point to learn and understand Processing. I went through the whole book and all examples just using two days. After that I had a confidence that I can start my part of the UNUI project with Processing. The book is concise and explains the basics very thoroughly and clearly. I could have even managed to do my program only by using this book and the Processing web side if I would have more time. However, I wanted to have some kind of paper manual also for quick reference. So I bought also:

Processing, A programming Handbook for Visual Designers and Artist, , Casey Reas & Ben Fry, 2007

This book is what is says to be - a Handbookwith a capital letter. It has 710 pages full of information and examples. This book works well if I need to check some basic things. I also like that the book contains information about actual Art projects and interviews of the Artists. I also like that this book has hard covers which make it easy to use it as a "bed-time reading book".  The minuses are that the book has rarely any color pictures.

Processing for Visual Artists, Andrew Glassner, 2010

I admit, that I bought this book mainly due to its cover picture that somehow appealed to me. I also liked that the book has plenty of color pictures and a lot of visually interesting projects. What I have liked about this book is that it explains also a lot of principles of computer generated graphics and image processing. Examples are well thought over and the book proceeds  in a iterative way from easy to more complicated examples. What I don't personally like is that the text has been written in a very chitchatting way.  I have not yet went though all examples, but I have been planning to do it soon. The minuses are that the book has soft covers and glued quite poorly.  I am afraid the pages will fall off very soon.

Learning Processing, A Beginner´s Guide to Programming Images, Animation, and Interaction, Daniel Shiffman, 2008

I bought this book because I first found the coding examples of the book  from the web. They seemed to be very interesting and useful  for me. Also I liked that the book also covered some examples about Video and Sound processing. The book is intended to be used as text book for introductory level programming course. Therefore the structure of the book is organized as lessons with related exercises and small projects. The book is maybe too basic for me, but as I already mentioned, examples are great. I also liked that the author did talk something about Java, too.

Electric Pea : How to connect vibration motor to arduino

I wanted to make an "electric pea" to my artwork : The Real Princess ( based on H.C.Anderssens fairytale the Princess and the Pea).  The idea was that when a person lays down to the bed, he/she would feel some odd vibration in his/her back. He or she could then imagine actually feeling the pea that was put under 20 mattresses.

The idea was to implement this by sewing a textile switch on to the  upper side of a thin matress (about 3 mm thick) and the vibration motor to the backside of the mattress. The weight of the person would trigger the textile switch and start the motor.

 I though that this task would be quite easy to manage.  I already had bought a pressure sensitive textile switch made by PlugandWear

I just needed a small vibration motor. They are easily available from any electric shop that sell Sparkfun products (product code ROB-08449).

The basic consept was that when someone was laying above the pressure sensitive switch, Arduino receives a signal to one of its input ports. Arduino would then steer the motor to vibrate until the pressure sensitive switch was again open (no pressure detected).

However I didn't want to use Arduino as a power source for the vibration motor for safety reasons. (Arduino is pushing 3,7 V - 4.9 v through the pins, and the vibration motor is operating at 2,5 - 3,8 V range.) Thus I needed external power source for the motor, a transistor to control the motor, and couple of resistors.

I was even able to draw the circuit diagram by myself:

Then troubles began.

I made an initial circuit to the protoboard.I downloaded the datasheet for transistor (BC639) from the web in order to figure out the correct pin order. I was sure that I had not made any mistakes - but the vibration motor was not running!!! I debugged sw and calculated the correct resistor values - nothing helped.

Luckily my husband still remembered how transistors can be used as diodes by short circutting the base and the collector of a transistor and using its two terminals as two terminals of PN junction diode. By measuring all the pins this way, he figured out the the datasheet that I had downloaded was not valid to my transistor (even the name of the transistor was the same !!) After figuring out the correct pin order of the transistor - everything worked fine.

The next problem was related to the pressure sensitive textile switch. The wires in the switch are very weak and almost as thin as human hair. They broke easily and are very difficult to connect to any "normal size" wires. The manufacturer instructs to use small uninsulated boothlace ferrules. I did have those, but still the connection was very sensitive to any movement of the wire. Finally I got the pressure sensitive switch working on top of my table (hard material below the thin matress), but the switch was not working properly on top of a soft matress I intented to use in my princess bed. :-(

I also noticed the the vibration of the motor was not strong enough to be noticed if there was any soft material below the motor.  :-(

And I also heard that the museum where the work was exhibited had to forbid people to climb to the bed. The bed is 280 cm high and does not have any safety railings. Still the parents were allowing very small kids to climb into it. Seems that parents do not have any common sense any more. :-(

Even though the project did not progess how I wanted, I learned many good lessons about transistors and textile switches. I am still planning to make a pressure sensitive switch totally by myself someday in the future.

Robots don't cry?

My art piece: ROBOTS DO NOT CRY? is currently presented at juryed exhibition ARTISTS 2010 by Finnish Artist association. Exhibition has 93 artworks that were selected from 1841 proposed ones.

The exhibition is at Tampere, Finland. My work is at Galleria Nottbeck. The exhibition is open during 30.10.-5.12.

The artwork consist of three robot balls that are covered by woolknit. These robotballs present crying songs (laments) that describes different feelings from joy, frustration, and sorrow. The crying songs have been traditionally presented at funerals, weddings, and other social situations. While presenting the songs, they also move slowly.

More information about this work can be found from my web pages.