E-textile and wearable II

Objective
DESIGN PROCESS INFORMED BY DATA.
This approach helps the design to respond to specific needs with a customized design.
I will make a stretch sensor to inform the digital design.

Anatomy Research
The relation between the human body and the electronic is becoming a stronger relation year by year. However, the human body doesn’t accept this electronics on all the body.
By a research from National Institute on Disability, Independent Living, and Rehabilitation Research, is well explained in which parts of the human body is possible to place the electronics in order to don’t have a discomfort.    Without be an impedance for the body and taking the best performance.
(link: https://wcc.gatech.edu/content/wearable-technology-affordances-body-maps)

 

MAP IMPEDANCE           –          MAP SENSOR PROXIMITY         –       MAP PLACE ELECTRONICS


STRETCH SENSORS
EeonTex Conductive Stretchable Fabric.
The Eeon tex is a bidirectionally stretchy nylon/spandex, elastic fabric coated with a
long-lasting conductive formulation. EeonTex Conductive Stretchable Fabric is highly conductive with a tunable surface resistivity in the range of 10E4 to 10E7 ohm/square. Additionally, it is extremely flexible with a mass per unit area of 4.8 oz/sq.yd. and a warp of 198–248 with an 85 percent warp recovery.

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notes: the resistance is depending on the fabric’s size.


PHYSICAL FARICATION
The purpose is to use the physical Sensor as an input in a digital simulation.

  • Build the stretch sensor. Cut a EeonTex swatch.
  • Place on the sides the metal button.
    The metal button will be useful to attach the sensor on a t-shirt, but also for its conductivity.

IMG_7943   IMG_7944

 

Sketch_Arduino_bb

  •  Open Arduino and prepare the board.
  • I used Firefly Firmata sketch, provided on the Firefly folder, to connect Arduino with  Grasshopper.

Problem: Arduino Serial Monitor
If the Serial Monitor makes a random number, check the Baund Value. The Baud value has to be the same for the sketch and for Serial Monitor

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  • Once the Arduino is reading the sensor stretch correctly,  is possible to open grasshopper. In Grasshopper will use FIREFIRMATA Plugin to visualize data.
    Below the Alghoritm:

FIREFLY FIRMATA

FIREFLY FIRMATA_.JPG

 

Notes: Be sure to close the Port in Arduino. The algorithm doesn’t work if there is already a COM port open.
Problems: Even if the algorithm was running correctly I couldn’t visualize the data.

 

 


FROM ARDUINO TO GRASSHOPPER
The stretch sensor inform the design

  • Connect the stretch sensor with the design-build in grasshopper and start to play!
    Find here the algorithm :
    Here the gh. file.

Cattura

 

02 01 03

01Video


STRETCH SENSOR – SOFT CIRCUIT
Once both Arduini Sketch and Grasshopper Alghoritm works is possible to think how to build the circuit on a t-shirt.

  • I design the circuit in illustrator to understand the electronics connection and the materials needs.
    For this assignment, I use the Lilypad, which allows me to work with more than one sensor

171126_arduino-draw-01.jpg

  • Once the graphics circuit is ready, I design it on top of the body following the body lines.
  • Draw correctly the whole circuit path, being careful to go under Lylipad connections ( PINS- BATTERY – GROUND )and to don’t cross the paths. This path will be used as input for the embroidery machine.

171126_arduino draw-04171126_arduino draw-03-03-03171129_graphic-06.jpg

  • To make a soft circuit I used the embroidery machine, using cotton and copper threads.
  • The embroidery machine helps to have a clean and precise path. However is important to use the correct thread according to the function. In my case, the stiff copper thread went against the stretch function.

 

IMG_7954IMG_7955.JPG

IMG_7975

 

  • The copper thread has to be sand in order to conduct the energy through the circuit.This action might ruin the fabric and brock the copper thread.

Notes:
-In order to have a powerful circuit would be better have both the thread conductive.
-The copper thread should be sand before the stitching.


PLACE THE SENSOR ON T-SHIRT
To conclude the assignment I  used the High conductive thread, stitched by hands.
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