WEEK 9
Wearables

Build your own soft actuators , Integrate them in a working project, Document what you did, Include all source files, Create an interactive object; if experienced with coding, focus on fully integrating a microncontoller into a textile circuit

Class 9

How to make flip dots (eyes version)

~

First prototype

The first prototype consists of an experimentation of the possible visual and movement result of Liza Stark's flip dots, but in a more visual version using the resource of the eyes.

Materials

The materials are the same as those specified in the tutorial. In this case I have used black neoprene and 0.1 inch magnetic wire, something thicker than normal, with the intention of giving less turns to the wire.

Process

This prototype has made an experimental process, which consists of using the same wire continuously to be able to handle 6 flip dots with a single controller.

Painting the magnets

The experiment has worked, and once connected to a battery, the magnets organize by polarity and you can paint them with color to visualize the flip of the magnets.

Analog test

In this example you can see that you can control the different magnets with a single controller, in this case I have connected a direct battery to the terminals of the wires, and I change the polarity inverting the connectors.

How it works

As we observe in the slide, the magnet changes color depending on the polarity of the battery.

HG7881 (L9110S) H-bridge + arduino

Details and programming exemple

But to be able to control this polarity digitally, I thought about using the HG7881 (L9110S) H-bridge programmed by an arduino, as you can see in the picture, these boards are used for dual stepper motors, but I decided to try the flip dots using the same process and programming.

Programming


 void setup() {
  pinMode(3,OUTPUT);
  pinMode(2,OUTPUT);
  // put your setup code here, to run once:

}

void loop() {
  digitalWrite(3, LOW);  //turn on one direction
  delay(500);
  digitalWrite(3, HIGH);   //turn off one direction
  digitalWrite(2,LOW);     //turn on other direction
  delay(500);
  digitalWrite(2,HIGH);   //turn off other direction

}

Digital test

The board with the board works correctly, but it heats up easily, so I think the wire is too thick to use on this board. So I decided to repeat the process but with a thinner wire.

Attiny44 vs Attimy45

Programing Attiny 44/45

Attiny 45 Data Sheet

Softrobot Board final project

The AVR are a family of RISC microcontrollers from the American manufacturer Atmel, specifically the ATtiny, are small AVR microcontrollers with 0.5 to 8 kB of programmable flash memory, encapsulated from 6 to 20 pins and a limited set of peripherals. Attiny 45 is highly recommended to incorporate in etextiles, being able to control the inputs and outputs for simple projects without having to resort to more complex microcontrollers like the Atmega. For this board I used the Attiny 44 and not the Attiny 45 because, beacuse Attiny 44 has 6 more pins, nedeed to control the drivers; however I incorporated the Attiny 45 into the softrobotics control board.

Softrobot Board final project

HG7881 vs Fab H bridge Board

H bridge Board Files\ Components\ Traces\ Interior

Fab Academy Output devices week.

For me the best option for the digital control of the flip dots is to replace the HG7881 (L9110S) H-bridge for the Fab H bridge. The fab H Bridge has the microcontroller incorporate in the board, and you can programs with the same code and is not necessary use the arduino. This means that the plate is better visible and easier to incorporate into the fabrics and wearables.

Pfaff creative 3.0

Again I have used the Pfaff creative 3.0 embroidery machine, but this time I have learned to embroider in two different colors. Here he prepared the frame with a black cotton cloth.

Embroidering eyes

First of all I embroidered the yellow parts of the eyelashes, to finish with the white color for the eyes. I have noticed that the thread is sometimes hooked, but I am satisfied with the results

Conectiing the eyes

We do the same process of using a single wire for the 6 eyes, but this time with a thinner wire and giving 15 turns to each of the eyes.

Sewing magnetic coil

Now only the magnetic wire is attached to the embroidery, so that with the soft thread a slightly more realistic result of the eyes when they are closed and opened.

Sewing magnet balls

The next step is to hold the magnetic beads to the eyes. For this I used the same needle with the same color.

Green eyes

Finally I painted the eyes green, with a special marker, but I think that the marker generates an anti-sliding layer, generates more friction to the flip dots, not rotating at the same time with the same fluidity. Therefore, my next step is to buy a varnish that protects it and makes it easier to move.