(UN)chastity

What is it?

(UN)chastity is a pair of pressure-sensitive g-string underwear made from biomaterials, embedded with vibration motors that respond to touch pressure. We explored and experimented at the intersection of e-textiles, biodesign, and intimate wearable technology, trying to make our artefacts as much open source and DIY as we could.

By establishing a communication bridge between Electric Intelligence and Primal Intelligence (reproductive programming), the narrative of the (Un)chastity follows the conduct of witchcraft and magic linguistics for an hyper sensorial interaction from human > human skin + artifact < digital input. Keeping this in mind, communication was acknowledged as non verbal interactions, triggered by intuitive and sensorial algorithms provoked entirely through physical contact. Which can also be associated with as an interface that is in close connection to the Sacral and Root chakra. Translating how the human body perceives and interacts with its surroundings based on intuition, sexuality and creativity.

This project focuses on reclaiming self expression, within the landscape of sexual affirmation and pleasure activism in a patriarcal and pseudo-pudic social contract. Gender and sexual dissidence aren't a deviance of the human behaviour but indeed a deeper understanding on self expression, trauma responses and power dynamics perceived in self and collective dialogues. The name indicates its unleash of desire and freedom, previously targeting enemies of compliancy of the notions of sin. Accordingly highlighting witches, demons, perverts, queers and freaks. (Un)chastity also amplifies the freedom of communicating within one self. A device to use for individual pleasure, a party of two or a cognitive orgy.

Materials

Within the material sourcing and research, non corrupting the biodegradability of each surface was was important for the ethos of our practices. Our ambition was therefore focused on testing and analysing the conductivity of the human body itself, different biopolymers and fluids in comparison to traditional hardware.

The following procedures showcase the process of selection based on the hybrid properties of an artifact that as biocompatible as it is communicative to the digital realm of electronics.

That being said, we worked on and decided which biomaterial to use as the first step. For an initial prototype we used leftover biomaterial made from gelatin and spirulina that we already had available.

In the meantime, we prepared a batch of another biomaterial, this time opting for a vegan option, by replacing the gelatin with agar-agar. We chose not to add any colouring so that it would be transparent, which was closer to the aesthetic of the flesh we wanted to achieve, but you can do as you prefer.

The recipe for the agar biomaterial can be found open source on the Bioplastic Cookbook.

!!! We suggest you to prepare the biomaterial in some advance, as you will need 3-4 days to get it fully dryed. Instead, you can also use a dryer oven as we did, for 5/6 hours at 35/40 degrees.

Also, keep in mind, in order to emboss electronic components onto bioplastics, each layer should be 0.8mm of thickness. Lowering this ratio can induce a higher risk of ripping the pattern while mounting. The agar biomaterial is usually a third of its thickness when dried. Keep that in mind while preparing the batch for the tray.

Then we experimented with algae string, made with alginate. You can also find this recipe open source by typing “algae string recipe” and experimenting with the one you prefer. After several trials with alginate, we extruded a filament that was also transparent, some thicker, some thinner. We tested alginate strings with and without graphene and sunflower oil. The graphene didn't show any addition power. Our hypothesis is that powders in the alginate interrupt the conductivity as it creates pumps. Plain alginate works best.

It was interesting to conclude that each material can not only be a conductive route for voltage as it applied direct resistance. Therefore according to the resistance needed for each component, a different thickness or composition is very likely to achieve those conditions. This ratio is also highly dependent on the hydration levels of each material. The drier it it the more resistance it shows.

For the bioplastic itself, we tested two recipes: basic agar (transparent, flexible, clean) and agar + dish soap (too thick, very white and opaque, but with a really interesting hand). At the end we chose to use the transparent basic agar version. We also confirmed that alginate string, while great as a capacitive antenna, has too much resistance to directly drive a motor.

The Material Stack

The final construction uses two layers of biomaterial, for a sandwich structure:

• Bottom layer — cast agar sheet, laid flat
• Wire web + alginate string — placed on top, acting as the capacitive antenna
• Vibration motors — embedded in between the 2 layers of biomaterial, positioned at key contact points
• Top layer — second agar sheet placed over everything
• Heat gun — used to gently melt and fuse the two layers together, sealing everything inside. (you may use whatever works for you, as much as it melts slowly and not too much the material, you will only need some heat to make sure they glue to each other)!!!

The Electronics

Board: Barduino 4 by Fablab Barcelona (ESP32-S3 based)

Three independent touch sensor → motor pairs:

• GPIO4 (TOUCH04) → wire web 1 → Motor on GPIO13
• GPIO5 (TOUCH05) → wire web 2 → Motor on GPIO12
• GPIO6 (TOUCH06) → wire web 3 → Motor on GPIO14

The Code Logic

The ESP32-S3 touch sensor works differently from the original ESP32:

• No touch → value near 0
• Light touch → value climbs significantly
• Hard press → value climbs even higher

Important finding: when the wire web is embedded inside biomaterial (agar), the capacitive readings are dramatically amplified compared to a bare wire. Our final calibrated values were:

• TOUCH_IDLE = 400,000 — below this, motor is off
• TOUCH_MAX = 2,000,000 — value at maximum pressure

These numbers will vary depending on your specific material thickness, wire density, and body. Always calibrate with your own setup using Serial Monitor first.

We use analogWrite() with PWM to translate that range directly into motor intensity. The map() function rescales the touch range to 0–255. constrain() acts as a safety clamp. The result is a continuous, pressure-proportional response for a smooth escalation.

No touch = motor fully off. Always.

Final code:

// PINS
const int TOUCH_PIN1 = 4;    // TOUCH04 → controls Motor 1
const int TOUCH_PIN2 = 5;    // TOUCH05 → controls Motor 2
const int TOUCH_PIN3 = 6;    // TOUCH06 → controls Motor 3

const int MOTOR_PIN1 = 13;
const int MOTOR_PIN2 = 12;
const int MOTOR_PIN3 = 14;

// CALIBRATION
const int TOUCH_IDLE = 400000;   // below this = no touch
const int TOUCH_MAX  = 2000000;  // value at maximum pressure

void setup() {
  Serial.begin(115200);

  pinMode(MOTOR_PIN1, OUTPUT);
  pinMode(MOTOR_PIN2, OUTPUT);
  pinMode(MOTOR_PIN3, OUTPUT);

  analogWrite(MOTOR_PIN1, 0);
  analogWrite(MOTOR_PIN2, 0);
  analogWrite(MOTOR_PIN3, 0);

  Serial.println("Ready — 3 independent touch+motor pairs!");
}

// Reads one sensor, drives one motor
void handlePair(int touchPin, int motorPin, String label) {
  int touchValue = touchRead(touchPin);
  Serial.print(label);
  Serial.print(": ");
  Serial.print(touchValue);

  if (touchValue < TOUCH_IDLE) {
    analogWrite(motorPin, 0);
    Serial.println("  → OFF");

  } else {
    int intensity = map(touchValue, TOUCH_IDLE, TOUCH_MAX, 0, 255);
    intensity = constrain(intensity, 0, 255);
    analogWrite(motorPin, intensity);

    Serial.print("  → Intensity: ");
    Serial.println(intensity);
  }
}

void loop() {
  handlePair(TOUCH_PIN1, MOTOR_PIN1, "Sensor 1");
  handlePair(TOUCH_PIN2, MOTOR_PIN2, "Sensor 2");
  handlePair(TOUCH_PIN3, MOTOR_PIN3, "Sensor 3");

  delay(20);
}

The handlePair() function is the key architectural choice — instead of repeating the same logic three times, the logic is written once and called with different pins. Clean, readable, and easy to expand.

DIY Lube Recipe

We wanted everything in the project to as much open source as possible, so we tested also some lubricant and "glue" (made with sugar, collagen, water and glycerine) as the initial idea was to have a patch attached directly to the skin.

Ingredients:

• Water (base)
• Flax seeds (natural mucilage, body-safe thickener)

Method:

• Simmer flax seeds in water for 30 minutes
• Strain out the seeds
• Let the gel cool

The result is a slippery, natural, water-based lubricant. No synthetic additives or packaging waste. Completely edible (and lickable). You can also add some flavours or essential oils to amplify the experience.

The User Manual

We also created a physical manual to accompany the object. It included:

• Description — what (UN)chastity is and how it works;
• A note on care — to make sure there is always consensus and safety;
• Setting the scene — to create a moment for you to explore your body and get playful;
• DIY Lube recipe — printed step by step.

CLL badge and use of AI:

Inevitably the process involves a third element of mediation, AI scouting of information. Although, we just used it for elements that go beyond the craft making of the artifact, which is something we take very mindfully. The use of AI is taken into consideration for the polishing of thoughts and conclusions taken along the process. The direction of this projects comes from a very personal perspective within the social structure of western culture, aesthetic formulations and field of interest are a mediation of two human and cultural intelligences.

What We Learned

• Biomaterials can be electronics substrates — but you need to understand their conductivity limits and liability for a long term use;
• Capacitive sensing is far more forgiving than resistive sensing for soft, biological materials;
• Powders in alginate disrupt conductivity — if you want colors make sure to use liquid ingredients;
• The heat gun fusing technique works as an artisanal approach to the wearable;
• The experience of making something intimate forces you to think carefully about who uses it, how, and in what context.

Looking Further:

• It would be important to consider the longevity of the electronic hardware, project the components from consistent energy flow and potential rusting when with contact and bioactive ingredients.
• Project with High potential for a new take on fetish gear and interactive/biocompatible underwear. This 3day propotype accomplished a good amount of results crossing bio and digital fabrication.
• The timing of the biofabrication must be respected, one misstep or rush over the moments of drying and setting can wear of its structure right before finishing the sample
• Substituting the plastic jumpers, even tho essencial now for the functioning of the motors, in a more extensive testing on conductivity of biomaterials.
• mount a protective casing for the barduino and direction of the wires. In the case of a G-string. It is possible and suggested a custom shape for a deeper personalised artifact. We would keep the cross structure of the Barduino itself. But focus on isolating the other pins and internal components.
• Replacing the Barduino for a Xao is high appealing for an even smaller electronic interface.

Project by Agnese Raimondi and Ivan Hunga Garcia

Made at MDEF Iaac, Fablab Barcelona and Elisava

References:

https://hackteria.org/wiki/GynePUNK

https://anarchagland.hotglue.me/?biomechatronic_machines/

https://quimerarosa.net/category/devices/english-devices/

https://quimerarosa.net/category/projects/

https://www.whitefeatherhunter.ca/