Human Nature

This work is the result of the Nature’s Wearables Node at PIFcamp 2017. It was realized in collaboration with Andrew Quitmeyer, Craig Durkin, Miro Krizman, Sanja Hrvaćanin and Mika Satomi and Hannah Perner-Wilson of KOBAKANT. The ritual was performed in collaboration with Vaclav Pelousek on synth, Jure Lavrin on drums and Dario on pipes.



Schematic

Circuit Diagram


Making-of


The plant sensor was discovered by accident. We were testing if the plant is conductive at all to be used as resistive sensors by connecting them with analog input of Arduino with 1M ohm voltage divider.. just like when you measure skin resistance. Originally when we did this experiment, it did not work well as the leaves we collected were dried out by the time we got them back to our tent. So, we were drenching them in salt water to see how this improves their conductivity… and then, accidentally, we had built the circuit in the diagram bellow.


.. and surprisingly it was detecting the human, touching the leaf very well. It works only when you are bare-footed on the grass. When you wear flip-flops, it does not work. We were a bit confused as it is hard to imagine that 3.3V from a small battery will go through the grass on the ground, through your body to the analog pin with enough current for sensing. But test after test, it seems to work! Amazing.


So, further we went on and tested this diagram. The plastic chair or the wooden bench at the camp seems to isolate us enough to be the sensing pin. Funny enough, when you sit just on the leg of the wooden bench, which is metal, it does not work. But when you sit in the middle of the bench, it works.

This experiment led us to rather odd situation of Craig spanking naked Andy with plants and riding him to a tree… well, do not ask why.


At this point, we were very confused if we are just creating antenna and sensing the noise or doing some kind of capacitve sensing. But if we lift the 3V connection from the ground, it does not work. so, it seems to be not exactly the capacitive sensing. And somehow it gives very reliable readings. We are hoping that someone will tell us what we were amazed here is something very simple that we have overseen. But for now, we are thinking this is some kind of witch-craft Slovenien mountain is making. (besides, the camp is located at a church with a lot of Jesus statutes)


We collected a lot of different types of plants from the woods and hang them on the string so they stay straight. When we used conductive thread to hang, they instantly became a plant organ.

Ok. now the principle is clear. We need one connection to the ground (or earth, or soil..), and a sensor connected to the input pin that is isolated from the ground. We decided to make two creatures. One of them is on a stilts isolated from the ground. Others can touch it and it makes a sound. The other one has a long tail touching the ground and as it runs around, the tail gets lifted from the ground isolating itself.

We gathered a lot of leafs and fern to make the mask and the dress of these creatures. They were mounted one by one with threads and rubber bands.

Miro made a nice big stilts from the wood he found around the camp. It was then covered with fern leafs and vine and other plants.

We mounted Lilypad Arduino on one of the stilts steps. The step was equipped with pressure sensor to detect walking steps. The edge of the steps were covered with conductive fabric tape to gain an electrical contact to the skin of the person riding the stilts. The detected sensor reading data was sent to computer via a Xbee wireless module.

Vaclav from Bastl Instruments joined us for the performance with his modular synthesizer. Dario added nice analog sound flavor with his flute.


During the Ritual, the steps of the stilt creature and the tail of the Green Human was triggering the sound samples. The signal was also sent to Modular Synthesizer as Control Voltage via Teensy so he can further use the signal to modulate sound samples or sonify signals.

At the end of the evening, we have taken the leafs one by one from the costumes and burnt them in the fire.

CODE

Here is the link to an Arduino sketch to read sensors, a max/msp patch and app (build from the patch for mac) for receiving sensor data and triggering sound , and an Arduino sketch for teensy to create fast PWM as CV for synthesizers.
https://github.com/mikst/pif_creatures


More photos of the project on flickr

photo credit: Katja Goljat, Mika Satomi