Finger Bend
Introduction: Finger Bend
Finger Bend is a sensor created to find a way of making finger bends inside of a glove, control light and sound.
The idea behind this glove is to then connect it to a body suit with other eTextile sensors for Immersive Audiovisual Performances.
What inspired me to create this project was the vision of performing freely through body movements. It is our innate interface. From my view, it is the obvious tool, instead of a trackpad, mouse, tablet, controllers, joysticks…
Inspiration: KOBAKANT’s sheath bend sensor.
Finger Bend was create for the E-Textile Summercamp’s Electronic Textile Swatch Exchange
The E-Textile Summercamp‘s Swatchbook Exchange is a platform for sharing physical work samples in the field of electronic textiles. 832
The exchange wishes to emphasize the importance of physicality and quality workmanship in an increasingly digital world.
I also posted it on my website: https://willpowerstudios.com/200910-finger-bend-sensor/
Supplies
Materials:
× Stretch Piezoresistive Conductive Fabric (https://www.lessemf.com/fabric1.html#11321)
× Copper Thread (from <PERSON>)
× Stretchy Jersey Fabric (online or textile shops)
× non-conductive thread (online or textile shops)
Tools:
× Sewing machine
× LED
× Breadboard
× Computer with arduino and the library for the microcontroller* you are using if it is not yet installed
× USB cable
× Lighter or heat gun (for shrink tube)
Examples of Microcontrollers: Arduino Uno / Nano / Teensy / ESP32
Step 1: Materials
Step 2: How the Finger Bend Is Made:
Step 3: Let's Start
Cut the stretch jersey fabric to the length of your finger from the knuckle to the beginning of your nail and width of ~ 8 cm.
Cut a piece of stretchy piezoresistive material and top fabric, both at the same size, similar to the top left photo.
Place piezoresistive stretchy fabric in between the base and top fabrics.
Step 4: Sew 3 Lines to Slide the 2 Copper Threads in Between Them
Step 5: Cut Extremities for Closing
Step 6: Sew the ‘inside’ to Close
Step 7: Slide a Finger Through It to Feel the Size
Step 8: Slide Copper Thread Through Pathways With a Tight Knot at the Entrance Before Going Through Hole
Step 9: Make Copper Pins
× Circle pin around copper thread
× Slide it through shrink tube
× Shrink it with heat gun or lighter to tighten it around the copper circle that you made around the male pin
× Do the same with the next thread
Step 10: How to Test It:
How to test it:
Connect the copper threads pins to alligator clips, and connect those to a multimeter with the ohm measurement selected. Observe the change in ohms as your finger bends. Make sure the copper threads do not touch
Step 11: Wiring
The Longer pin of the LED goes to pin 4 of the board.
Step 12: Make the Connections
Step 13: Arduino Code
// WILLPOWER @ Swatch Exchange 2021
#define LED_BUILTIN 13
#define LED 4
int bendSensorValue;
int light;
// the setup function runs once when you press reset or power the board
void setup() {
Serial.begin(9600);
// initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
pinMode(LED, OUTPUT);
pinMode(A0, INPUT_PULLUP);
}
void loop() {
bendSensorValue = analogRead(A0);
light = map(bendSensorValue, 740, 840, 255, 0);
light = constrain(light, 0, 255);
digitalWrite(LED_BUILTIN, light);
digitalWrite(LED, light);
Serial.println(bendSensorValue);
}
/*
All Finger Bends are a bit different in terms of the data they are generating, so you may have to calibrate yours.
To do this, after you uploaded your code to your microcontroller, open the Serial Monitor in Arduino and compare the numbers between the highest and lowest… basically when you finger is straight versus bent.
Replace these numbers in the map function from 740, 840 to your numbers.
Keep playing with them until you get the result desired.
( the code is also on github: https://github. 673