Reactive Spaces and Media Architecture 48-734 | Polish Hill, Pittsburgh
Professor: Jakob Marsico | Fall 2018
Programs Utilized: TouchDesigner, Rhino, Adobe Photoshop, Adobe Premiere
Light, Camera, Action was one of five projects in the final showcase at the end of the semester. The space that we chose to occupy was the stairwell entry to the entire gallery equip with high ceilings and a couch to relax on in the back of the space. We manipulated the entryway space by dropping down and exploding the ceiling with mylar and scrim-covered rectangular panels. Visitors traveling through the entryway have their movements captured by a webcam in the back of space, inputting their actions to TouchDesigner which would trigger the DMX lights to grow increasingly magenta or red depending on the amount of movement. These lights would then be reflecting and refracting off our panels, creating a faceted environment of rippling lights and bright pigments to raise expectations for the rest of the exhibitions.
Our project visually demonstrates an interpretation of how our visitors are influencing the space with their presence.
One of the biggest roadblocks we had to face was figuring out how to hang the panels inside the space. The height from floor to ceiling was 18', rendering it impossible for us to anchor the panels to the ceiling, even with the help of a ladder. Our solution was to build a lightweight metal frame with cross bracing spaced at the intervals corresponding with the distance between individual panels. The frame ended up being 20' x 10', allowing it to span the majority of the 24'6" x 10' space.
The frame was drilled into the brick walls of the room using concrete screws after being assembled and lifter to a height of 10' above the first floor. Unistrut channels and non-invasive mounting arms were used to hold up the DMX lights around the perimeter of the room.
Sketch of metal frame with cross bracing to hold up panels
PANELS AND LIGHTING
Sketch of panel placement and planning
The most challenging part wasn’t wrapping the materials carefully around the PVC frames but rather, figuring out how to cut the fishing line to angle the pieces as intentionally as possible. We used silver carabiner clips to attach the 4 individual strands of fishing line coming from each of the four corners to anchor into a 5/16″ hole in the metal framing.
We then worked with the DMX lights themselves, continuing to tweak our reflections and diffusions to light up the entire space while still ensuring that spots of interest were created to add variety to the space. These spots ended up being the focus of most guest photo shoots in the stairwell.
Touchdesigner triggering the lights using video input
A webcam was mounted at the back wall, tracking blob movement near the top of the stairwell. With increased detected activity, TouchDesigner would trigger the lighting to skew magenta and with the most blob movements, changed to red. With no detected movement, the environment was rendered to a default state of indigo.
We experimented with various color slider speeds and found that a faster change rate allowed for people walking through the space to immediately notice the change in color and look up as they walk down. This created a connection between the space and the people moving through it, catching their attention and encouraging interaction from visitors to achieve desired environmental results.
We found blob detection a bit too complex and finicky for our application, so we opted for a much simpler approach. A five-frame buffer was creating and comparing the difference between the first and last grayscale images. The bigger the difference between the two images, the higher the number of white pixels. We used the percentage of white pixels in the resulting image to compute a number that would control the phase of a gradient ramp. A presence of more white pixels signified more motion, shifting the ramp higher towards red.
Recorded and edited by Lexi Yan