To Leaf? Or not to Interleaf?

That is the question discussed by the engineers, among other things.

Remy's fall-back plan, if nothing else works, is to create a series of interleaved files that would play upon the triggering of the second sensor, since the sound from the first file would already be playing upon trigger of the first sensor. Dr. Marantz pointed out that humans perceive sound gaps at 15 milliseconds. So: using a typical sound duration of say, 30 seconds, that would make it 66.6 samples a second or 2000 samples (actually 4000 samples--forward and backward). Since sound files aren't big, we could fit it onto a chip and (this is Remy talking) a script could be written to create the files and the microcontroller could access the proper file according to when the second sensor is tripped.

Dr. Marantz stresses that this be a last resort as other solutions might prove to be less complicated. We're set to meet next week again, either on the phone or all my office. Remy sent a parts list so he can get to work:

1) http://www.robotshop.com/midi-music-shield-v2-arduino.html  $27.50 It's listed for $10 at Radioshack; but it's out of stock. [Maybe it's in-store; I'll check when I go get some coffee in a little while]
2) http://www.digikey.com/product-detail/en/ZMOT1AHH0F0AG/269-4826-ND/2665316 $24.02

Further talk about the sensor:

1. Of course it needs to be calibrated, since the light conditions will vary on each location and the work is site-specific, reconfigured according to the space. But the field of sensitivity is another factor, because the panel is free-hanging. A wider angle would pick up viewers farther from the piece. This is easily taken care of since a collar (straw) can be placed around one (or both) sensors so the units are triggered only when the viewer passes directly in front of the panel. That's easy enough to fix and will be determined as the installation is laid out.

I have given serious thought over the development of this work to the order of the pieces, although the distance between them will vary.

There will be a lead-off front and center, pushing the more abstract ones in between those whose imagery is more easily identified. The traffic will very somewhat, depending on the number of viewers, but, if the show at the Grace Gallery was any indication, viewers will walk around the first piece to what's directly behind it, to circle around and see the pieces they missed in the front on the periphery. from there they leave the exhibition space.

Concluding that they make two circles around the work and walk out. This is because the door is in one place, as it would be in Trenton. However the Grace is a deep space whereas the ArtLab is wide and shallow, so while the order of the pieces would be the same, their spacing would be farther apart left to right rather than front to back. 

The original schematic was done assuming a walk-through traffic flow, here it is from previous posts.




More on the LED panel: 

With the unit in-house and a little more time, I got a chance to think about the entire process of what needs to be done. 

Gotta take the thing apart.

After seeing how it functions, I can determine how and where to drill the sound unit into it. The sides are made of metal; I haven't taken a good look at the back as yet. But on first sight, I can drill the unit onto the back, have the speaker wires travel through the back to the sides or the top (wherever the speaker(s) will end up being) and plug into the speakers from there. I had the idea of asking the technicians to do it in China, but a little voice in my head is telling me (actually shouting) No.

The moiré pattern is formed by an air bubble that moves across the perforated screen. If that is taut, perhaps with framing springs the problem might be resolved. Or, alternately, vacuum the air out.

Some issues in the manufacture: When drilling the screws to affix the frame, the builders shattered the back transparent panel, which may not be a problem, but I wouldn't want to find out. That will be on my list to the LED guy in China. 

However, I will ask them to drill the holes on the side of the frame further apart and on the bottom as well. The unit they sent is a commercial item with no traffic meant to flow around it: e.i.: it would either hang on a wall or in a window. Since the panel will be free hanging, the cable has to hang outward, so the holes drilled for it have to be closer to the corners. Also, it's possible that I might not need a second electrical source; just another set of holes which would allow the power cord to travel from the top or the bottom. I'd only have to re-orient the image in the panel.

Here's the comparison from the Duratrans (left) to the Duraclear. The choice is obvious, tests will have to be made on all images; since the darker ones may need to be boosted while decreasing the contrast.