Steve’s Stuff

Five days until the due date and Team 5 is looking good. Here’s what has been going on.

Muhammad got the car driving around and programmed it for random movement. Instead of using some sort of infra-red “thing” to keep the car within the canvas, it’s programmed to back up automatically if it bumps into something. From what I can tell, Muhammad spent a LOT of time on this. His part works and is essentially done (although he’s got a few improvements).

Kendra and I have been talking about the artist’s statement a lot. She’s got a lot of great ideas and good things to say - it’s been fun to work together. She’s scheduled to fabricate the car’s body as soon as Muhammad is finished with it. This sounds difficult, but apparently, she’s cool with it. Kendra is also providing the canvas and the boundary. We discussed the use of a boundary and decided that we would like to let the artist wander off of the canvas, but since we’re performing in a public space that may not wish to have paint on the floor, we’re keeping it reigned in. It’s purely for practical reasons.

Aaron is doing work with sensors. I’m not sure exactly how that’s coming along. I haven’t seen them working yet, so I don’t know if there are any problems or if they’re in good shape. Aaron was in favor of scaling our original goal of 12-16 sensors back to 6, so that’s what I think we’ll end up with.

Lauren was in charge of researching abstract expressionism and working with Prof. Harrison to get the logochip to interface with Pd. She found some info on wikipedia and a couple other sources and is now recording herself reading them aloud. Kendra and I had a few suggestions, so she may be redoing some of them. We’ll hopefully have them by Thursday night. I ended up taking over the Pd interface because I needed to see it working before I continued with my own work.

I’ve spent hours with Pd creating some odd sounds to accompany our artist. I settled on classic synthesis techniques that were used roughly during the time of abstract expressionism including additive and subtractive synthesis as well as ring modulation. I’m also forgoing the sophisticated sounds common today in favor of the sine, square, and pulse waves used when sound synthesis was in its inchoate stage.

I’m creating an approximation of a square wave using a wave table in Pd. Although it’s possible to create a perfect square wave, analog techniques in the late 50s did not have this option. I’m also using the wave table to generate pulse waves and one other “original” creation. At this point, most values that will change are connected to random number generators, but I hope to replace them with sensor inputs as soon as the sensors are finished.

The other part of my Pd work involves the sampling of Lauren’s voice as she reads statements on abstract expressionism. For this, I’m feeding the samples through a strange comb filter. This consists of four short (less than 1ms) delay lines. The output of each delay line is ring-modulated by an oscillator set at 3000, 1500, 1000, and 500, respectively. This creates a metalic, crunchy sound that I can mix with the pure, unfiltered voice. The filtered output is slightly delayed further to give the voice an ambience. The oscillator values can be changed to produce varying degrees of distortion, but the ratios remain the same regardless of the oscillator value.

The audio samples are not triggered by sensors (because we don’t want to hear the same thing twenty times), but various parameters in the sampler may be controlled by sensor input. I’m also experimenting with reading the sound files to a table and then programming Pd to let me scrub through the audio selecting various starting and stopping points as well as different speeds of playback. I have this working, but I’m not sure that it fits with the project, so I may not include it on this particular piece. The effect is similar to granular synthesis, only on a larger scale, but since this is a recent technique, I can’t really justify its usage.

Things are looking good. I’m excited to see it all come together. I’m also looking forward to what the other teams come up with as well.