For this final project, I looked at different ways to conduct electricity which might mean the form of a lighting object could change. A major challenge in creating lighting is hiding wiring and traditionally the form has also centered around the source of light. As LEDs are changing that I wanted to think about how the form might be able to change.
I went to Material Connexion where I saw many kinds of conductive fabrics and metallic composite materials. I had thought about the possibility of weaving LEDs into a mesh but given then need for a positive and negative lead this seemed to be not as possible.
I also did research online into different types of conductivity and other materials that might be suitable, and one of the things I found that I thought feasible was a salt solution.
If I was going to have exposed wiring a consideration was also safety, but I didn’t find any conclusive answer in my research about what might be a safe level of current or voltage exposure.
All of these considerations led me to a couple of things in my designs, such as setting up the LEDs in parallel to allow low voltage and multiple LEDs, as well as to deploy a positive and negative “lead”.
In one design I set up two boxes with a concentrated salt water solution (4 tsps in 150ml), one being the positive side and one the negative. I found at lower concentrations the resistance was much more variable and at this concentration it started to become very consistent at around 1 ohm. The salt water was supposed to act as both conductive material and diffuser for the light.
The LEDs I used were 3.3V/25mA forward current. However with 5 of them, one 3V battery didn’t supply sufficient power. 2 3V batteries created a nice amount of light and it didn’t seem to require further resistance, even though I thought the salt water may not create enough.
It did actually create a nice light, but I had a lot of issues making the containers watertight so they couldn’t be stood up as originally envisaged.
The second design I created was based on a more standard conductive material but I used it in a different form. I knitted and crocheted 28 gauge silver plated wire and inserted it into an acrylic box which served as a frame and light diffuser. In one case I used one 3.5V very high brightness LED and 2 3V batteries, so I also wove a resistor into the knitted conductive mesh.
In the other case I used 3 3.3V medium high brightness LEDs with one 3V battery.
Ordinarily this kind of case would be difficult to use without having an extra hidden compartment for the wiring and sources of electricity.
For both of these I created a lid that snapped on and off with a magnet, or could be rotated, and in doing so, was the switch for the light.