New Textiles 2012 » anasto

A Dress that Breathes

anasto — Mon, 21 May 2012 23:00:55 +0000

As a continuation of my project from the moving textile assignment, I made a dress with fabric origami panels that are actuated by nitinol shape memory wire. The repetitive contracting and expanding motion of the panels is reminiscent of breathing. The panels are made in a pair to mimic anatomical lungs.

I created a pattern for a dress with a straight skirt and a princess-seamed bodice and sewed the dress out of polyester satin. To make the origami panels, I laser cut the fold pattern on a piece of cotton/poly blend fabric. Then, I folded the fabric along the fold lines and stitched the folds in place. To stiffen the fabric, I made my own starch (by dissolving 2 tbsp. of cornstarch in 1/4 c. of water, then whisking in 2 c. of boiling water) and dipped the fabric in it, then set the starch by ironing the fabric when just barely damp.

To make the nitinol springs, I wrapped wire around a screw and held it in place with nuts. I put them in a furnace at 500 degrees Celsius for 10 minutes to set the shape.

The Voronoi lace pattern of the peplum is inspired by the Voronoi patterns present in alveoli, which are structures in lungs that are responsible for gas exchange.

: sciencephoto.com

I laser cut the peplum pattern that I designed using Processing and a random Voronoi generator code.

A Lilypad Arduino is used to control the nitinol actuated panels. The panels are programmed so that the current switches on and off, causing the wire to expand and contract to create a repetitive motion that is reminiscent of breathing.

Here are videos of the dress in action:

The motion is quite subtle, but I think that is ideal for mimicking respiration since breathing is subtle as well. I would have liked to have had the panels be attached so that they contour the body of the dress. However, when I tried this, the panels were too constrained to produce the desired motion. I was pleased with how the fabrication of the fabric origami worked out. I think it would be interesting to use this technique to make other origami structures out of fabric.

Final presentation slides

Project Update

anasto — Tue, 08 May 2012 03:52:30 +0000

My plan is to make a dress with fabric origami panels that will be actuated with nitinol to create the illusion of breathing. I will make two panels for the front of the bodice of the dress. To add to the theme of respiration, I will add laser cut voronoi lace to the skirt of the dress to emulate the voronoi patterns of alveoli, which are hollow structures in lungs that allow for optimal gas exchange with their large surface areas.

I purchased fabric and a battery that will be appropriate for my project. I trained nitinol that I ordered from McMaster by wrapping nitinol wire around screws and heating them in the furnace to create spring shapes. I will use these nitinol springs to move my origami fabric pieces.

I experimented with cotton fabric and a starching process to create stiff fabric origami. First, I laser cut the origami pattern with dashed lines onto the fabric.

Then, I folded the fabric along the dashed lines and sewed the folds in place. I made my own starching solution by dissolving cornstarch in cold water, then adding boiling water. I dipped fabric in the solution and let it dry until barely damp. Then, I used an iron to press folds in place and set the starching. I was satisfied with the result and will use this type of fabric and technique for my garment panels.

These are the remaining steps to complete my project:

Create the pattern for the dress and figure out appropriate dimensions for lace pieces and nitinol actuated panels.
Laser cut lace and origami pieces.
Stitch and starch origami pieces.
Cut and sew dress from the fabric I purchased.
Iron on lace pieces.
Add origami panels with circuitry.

I will complete the first three bullet points this week, and the last three bullet points next week.

3D printed “knitting”

anasto — Tue, 01 May 2012 15:55:18 +0000

This is my first 3D designed and printed object, so I tried a basic textile design featuring rows of interlocked loops, reminiscent of a knitted textile. I used SolidWorks, a 3D CAD design software popular among engineers and designers. First, I made a single “stitch”.

Then I made an assembly of these stitch parts in rows. I rotated and fit together the stitch rows in an alternating pattern to make the loops interlock.

This is the finished 3D design:

I used a 3D printer at MIT’s main campus and used ABS plastic. I would have preferred to use a softer and more flexible material, but this was the only kind of material available for the printer I used.

The textile is printed with lots of support material on a tray.

I chemically dissolved the support material in a bath. Here is the end product:

Here’s a video of the textile in action. The textile can bend and is quite floppy, considering that it is made from stiff ABS plastic.

Topological Knitting

anasto — Tue, 10 Apr 2012 16:30:18 +0000

I was fascinated by creating 3D knit structures with interesting topologies on a knitting machine, and wanted to see if I could create 3D structures by hand. Most hand knitting that I have done creates surfaces with some texture, but not with 3D protrusions. Here, I have experimented with a few techniques.

With the knitting machine, and the pattern that was provided for part 1 of the assignment, I knitted this swatch with a triangular protrusion.

By holding stitches, protrusions are created with the knitting machine by selectively knitting stitches more or less times than other stitches, creating a desired 3D shape. I have never tried this method by hand, so I decided to see what kind of structures could result by doing this same method with hand knitting.

I created this stitch pattern to make a swatch with 3 columns of bumps that are made by selectively working some stitches more than others, similar to the method of the knitting machine. However, with hand knitting, the gauge is larger and there are less stitches, so the visual effect is more subtle.

Using size 7 needles and worsted weight yarn, cast on 27 stitches.
Stockinette stitch first four rows (knit and purl every other row)
All in stockinette: slip 1, knit 7, slip 1. continue working only these nine stitches. slip 2, purl 5, slip 2. slip 3, knit 3, slip 3. slip 4, purl 1, slip 4. and backwards: slip 3, knit 3, slip 3, slip 2, purl 5, slip 2. slip 1, knit 7, slip 1.
Continue onto next nine stitches in the row in the same pattern. Then do the next nine after that.
Purl, knit, purl next three rows.
Continue repeating the pattern until desired length.

I also tried a technique different from the one employed by the knitting machine. Here, I created a stitch pattern where stitches are put on stitch holders and then knitted after the main body of the swatch is completed. This creates flaps that stick out perpendicular to the surface of the swatch.

Using size 7 needles and worsted weight yarn. Cast on 24 stitches, stockinette stitch 6 rows.
On a purl row, make increases on the first 6 stitches by purling in the front and the back of each stitch. Use markers to keep track of the increased stitches. Purl the remaining stitches in the row.
For the increased stitches: knit 1, slip 1 onto a safety pin or scrap piece of yarn, repeat until you have knitted 6 stitches and placed 6 stitches on hold. Knit the remaining 18 stitches.
Stockinette stitch 6 more rows.
On a purl row, purl the first 6 stitches, then increase the next 6 by purling in the front and the back of each stitch, purl the remaining 12 stitches.
In the next row, knit the first 12 stitches. For the increased stitches: knit 1, slip 1 onto a stitch holder until there are 6 knit and 6 on the stitch holder. Knit the remaining 6 stitches.
Stockinette stitch 6 more rows.
On a purl row, purl the first 12 stitches, then increase the next 6 by purling in the front and the back of each stitch, purl the remaining 6 stitches.
In the next row, knit the first 6 stitches. For the increased stitches: knit 1, slip 1 onto a stitch holder until there are 6 knit and 6 on the stitch holder. Knit the remaining 12 stitches.
Stockinette stitch 6 more rows.
On a purl row, purl the first 18 stitches, then increase the last 6 by purling in the front and the back of each stitch.
For the increased stitches: knit 1, slip 1 onto a stitch holder until there are 6 knit and 6 on the stitch holder. Knit the remaining 18 stitches.
Stockinette stitch 6 more rows. Bind off.
Pick up stitches that are held on safety pins or scrap yarn. Knit 5 rows (garter stitch), then bind off. Do this for all the stitches on holders.

A Garment That Breathes

anasto — Tue, 03 Apr 2012 15:18:37 +0000

For the final project, I will expand on my project from the moving textile assignment. I folded a collapsable structure with paper and used nitinol shaped like a spring to expand and collapse the structure as the current is switched on and off. The resulting motion made the paper structure look like it was breathing, so I called it “paper lungs”.

I will translate this concept to a larger scale project, where I will create a garment with fabric instead of paper. The creases will be created in the fabric by stitching fabric together along fold lines. I will use nitinol springs along the length of the panels to expand and contract the fabric, to give the impression that the garment is breathing.

presentation slides

Scaled, Rotated, Translated

anasto — Tue, 20 Mar 2012 03:39:02 +0000

I made a tank top with laser cut iron-on lace. The same pattern, created computationally from a Voronoi diagram generator, was laser cut out of iron-on adhesive backed fabric three times in different sizes and ironed on the front of the shirt in different rotation positions.

I created a pattern for a tank top based on the dimensions of another top that I had in my closet. I modified the neckline to make it a boatneck shape, maximizing space for the iron-on pieces to let the focus of the top be on the lace designs.

The pattern for the lace was generated using Processing with a Voronoi diagram generator. I modified several parameters in Jennifer’s spiral and circle Voronoi code, which draws points in the pattern of a combination of spirals and circles. Voronoi diagrams are generated from this set of points by partitioning the plane into convex polygons so that each of the points are contained within the polygon and any point in a given polygon is closer to this generating point than to any other generating points (more at Wolfram Math World).

This is the resulting lace pattern after cropping lines which extended beyond the drawing area:

I ironed iron-on adhesive to a piece of yellow lining fabric. Then, I laser cut this pattern three times in slightly different sizes.

I used tweezers to carefully remove the paper backing. Then, I arranged the three lace pieces on the shirt front and ironed them in place.

Here is the Processing code for the Voronoi lace pattern:

/*This example illustrates a simple method to generate a set of deliberately placed

points to control the structure of a voronoi diagram. This particular example

combines spiral and circle structures to produce the overall design.*/

void setup() {

size(600,600,P3D); //size of your intended pattern

noLoop(); // don’t need to use the draw loop

/*unique name for your file. if left unchanged,

will simply save file with current milisecond*/

String fileName= “voronoi”+millis()+”.pdf”;

beginRaw(PDF, fileName); //enables you to save your design to a pdf

setupVoronoi(); // create your voronoi generator

// =========GENERATE CIRCLES=============== //

int outerCircle_center=10; // variable to set the center positions of the outer circle

int diameter = 20; //diameter of your circles

/*generates 5 evenly spaced points, one in the center of your stage and 4 in the outside corners

as set by the outerCircle_center value. These points will be the center of the 5 circles in the final design */

voronoi.addPoint(new Vec2D(width/2, height/2)); // adds a new point to your voronoi generator

voronoi.addPoint(new Vec2D(width/outerCircle_center, height/outerCircle_center));

voronoi.addPoint(new Vec2D(width-width/outerCircle_center, height/outerCircle_center));

voronoi.addPoint(new Vec2D(width-width/outerCircle_center, height-height/outerCircle_center));

voronoi.addPoint(new Vec2D(width/outerCircle_center, height-height/outerCircle_center));

int drawLimit = 3; // we will define the circles by a set of evenly spaced points. This variable controls the number of points in your circles

for(int i=0;i

float _alpha = (float)Math.PI*2/drawLimit; // determines the degree position of your current point

float cirtheta = i*_alpha; //current position on circle for your intended point

drawPoint(width/2, height/2,cirtheta,diameter); //this will generate the center circle

/*these calls will generate 4 outer circles with diameteriuses that are one half that of your center circle*/

drawPoint(width/outerCircle_center, height/outerCircle_center,cirtheta,diameter/2);

drawPoint(width-width/outerCircle_center, height/outerCircle_center,cirtheta,diameter/2);

drawPoint(width-width/outerCircle_center, height-height/outerCircle_center,cirtheta,diameter/2);

drawPoint(width/outerCircle_center, height-height/outerCircle_center,cirtheta,diameter/2);

}

// =========GENERATE SPIRALS=============== //

int centerLimit = 300; // variable to control the diameter of the spiral

int theta = 0; //increases with every point in your spiral, producing the spiral effect.

//this will draw the four smaller spirals

theta=0; //reset theta

//this will draw the four larger spirals

for(int k=0;k

theta +=1;

drawPoint(width/2,height/4,theta/16,theta/2);

drawPoint(width/2,height-height/4,theta/16,theta/2);

drawPoint(width/4,height/2,theta/16,theta/2);

drawPoint(width-width/4,height/2 ,theta/16,theta/2);

}

drawVoronoi(); //renders your voronoi

endRaw(); //ends the recording

}

void drawPoint(float orgX, float orgY, float theta, float diameter) { //function that generates and adds circular points

float xPos = sin(theta)*diameter+orgX;

float yPos = cos(theta)*diameter+orgY;

voronoi.addPoint(new Vec2D(xPos, yPos));

}

Composite Variations

anasto — Tue, 13 Mar 2012 15:54:10 +0000

This week I made three composite textiles using a duplication polymer that is mostly used in dentistry. I also use this polymer to make many of the samples I use in my research, so I thought it would be fun to use it in new and experimental ways.

I made a composite with acrylic yarn and purple duplication polymer. First, I crocheted a fishnet pattern out of purple yarn.

Then, I mixed the polymer components 1:1 in two parts and poured it over the net in an acrylic tray. I wanted the yarn to get soaked with the polymer to see what kind of texture would result if the polymer got in between the yarn fibers.

The resulting textile has an interesting combination of smoothness from the polymer and roughness from the yarn texture.

In this next textile, I wanted to experiment with a composite that combines two-dimensionality and three-dimensionality, with balloons and duplication polymer. I inflated several latex water balloons and taped them to the bottom of an acrylic tray.

I then mixed and poured the duplication polymer into the tray. The polymer, when set, holds the balloon bases in place.

The resulting textile is a 2D sheet of polymer with 3D balloons protruding from the surface.

Unfortunately, the balloons slowly deflate after a few days. So, I suppose one could say this textile also has a temporal component.

My third textile probably doesn’t really go with this assignment, since it’s technically a woven material, yet it is made out of a non-woven “yarn” that is cast with duplication polymer. This isn’t strictly a composite by the traditional definition, but I would say it is a composite of techniques since it combines a non-woven fabrication process to make the yarn with a traditional weaving (or knitting) technique. My labmate makes these green “spaghetti rods” for his model experiments on rod mechanics (most recently, the mechanics of curly hair!). I thought it would be interesting to knit these rods into a textile. I made “yarn” with the duplication polymer using a syringe and plastic tubing. I taped the tubing to a long piece of 80/20 to hold it in place and poured the duplication polymer into a syringe. The polymer is then extruded from the syringe into the plastic tubing.

Then, the plastic tubing is cut away after the polymer sets. This is what the “yarn” looks like:

Then I used knitting needles to knit a small sample. This material was particularly difficult to knit with since the “yarn” is quite rubbery and doesn’t like to slide along the knitting needles.

This is what the finished sample looks like:

Paper lungs

anasto — Tue, 06 Mar 2012 02:28:33 +0000

I decided to call this project “paper lungs” since the way piece of origami contracts and expands with the motion of the nitinol wire reminds me of lungs. To amplify the subtle motion of nitinol wire, I folded a chevron patterned origami piece that cooperatively expands or contracts in both the horizontal and vertical directions with pulling or pushing in either of those directions. This way, actuation in one direction would lead to the entire structure expanding or contracting.

I trained 0.25 mm nitinol wire by wrapping it around a screw and putting it in a furnace hotter than 500 degrees C. The resulting nitinol piece acted like a spring. I stretched the spring and soldered it pieces of copper tape at to two ends of my origami piece.

When the wire heats up by running a current through it, it returns into the tightly coiled spring shape and moves the paper ends along with it. I used an Arduino Lilypad and a 3.7 V battery to control and heat the wire.

The 0.25 mm nitinol can withstand 1050 mA of current. With a 3.7 V battery, the resistance should be at least 3.52 Ω to prevent the nitinol wire from overheating and losing its shape memory. I measured the resistance to be 2.7 Ω, which was too low. To fix this, I added a 1 Ω resistor in series to make the total resistance 3.7 Ω, putting the current at 1 A, which the wire can withstand. Unfortunately, before measuring the resistance of the wire, I tested the nitinol wire using the battery and perhaps made the wire lose some of its shape, as I found the spring to be less “springy” after testing it a few times. Now I know to be mindful of the resistance of the wire and how much current it can handle.

Glittering Mittens

anasto — Mon, 27 Feb 2012 02:39:18 +0000

I used LEDs as rhinestones to make mittens sparkle in response to hand motions. Using velostat, I made a resistive sensor that senses how bent or flexed the wrist is. Incorporating the sensor into the natural bending motion of the wrist, more LEDs light up the more the wearer moves the wrist, capturing and amplifying gestures that the wearer might make while conversing excitedly.

To make the sensor, I used two pieces of felt, conductive thread, and two strips of velostat. I didn’t take a picture while making the one for the glove. However, they were assembled in a similar manner to this other velostat sensor that I made. The conductive thread is stitched across the felt pieces and the velostat pieces are sandwiched in between the two layers.

I made a pattern for a mitten by tracing my hand. I cut the pieces out of fleece and used snaps to connect the Arduino Lily Pad and the sensor to the mitten. I decided to stitch the LEDs to bows and have the bows conceal the microcontroller.

These are the measurements and calculations I made with the velostat sensor.

	activated	unactivated
resistance	1 MΩ	4 kΩ
excpted voltage	0.379 V	3.57 V
measured voltage	0.30 V	2.5 V

Here is the glove in action:

If I made this glove again, I would put the sensor over the fingers rather than the wrist, since the fingers have a wider range of motion.

Color Changing Flower Applique

anasto — Tue, 14 Feb 2012 02:41:34 +0000

Using thermocrohmic paint, cotton, conductive thread, a switch, a battery, and some scrap fabric, I made this flower applique. This could be used as a decoration that is sewed or glued onto a variety of garments, or perhaps fastened onto a safety pin or a hair barrette.

Using a multimeter, I made these measurements:

voltage of the battery: 3.7 volts
resistance of traces: 1 Ω and 22.4 Ω

Using Ohm’s law, V = IR, I calculated that the current should be 158 mA, which would be enough to change the color of the ink when the current passes through the thread. However, when I measured the current with the multimeter and the battery plugged in, I got a reading of 78 mA, which is slightly below the threshold for color changing.

This video shows the applique with the switch on. The color change is quite subtle, probably due to the fact that there isn’t much current going through.

First, I stitched the circuit components and a circuit using conductive thread.

Then, I painted the fabric with thermochromic paint. I tried a few colors and found that this green color showed the most dramatic color change. I discovered that the trick was to use only a little bit of regular paint mixed in with the thermochromic paint.

Then, I stitched some layers of sheer yellow fabric and red fabric for the flower’s center. This layer conceals the underlying circuitry.