====== Week 6: Computational couture ======

This week's assignment was to create a parametrical pattern using **Grasshopper**, the plugin for Rhino, and 3D print it. I created 2 designs - one 3D printed on fabric and one stand alone design. Both were printed using flexible filament. To download the file for the weave, visit: [[https://oscircularfashion.herokuapp.com/project/-L6RBZO2WvKMLb8Uni3l|https://oscircularfashion.herokuapp.com/project/-L6RBZO2WvKMLb8Uni3l]]

{{:fabricademy2017:students:cheung:final_circles.jpg?300|final_circles.jpg}}{{:fabricademy2017:students:cheung:final_weave_1.jpg?300|final_weave_1.jpg}}{{:fabricademy2017:students:cheung:final_weave_2.jpg?300|final_weave_2.jpg}}

===== First design =====

For the first design, in Grasshopper I created a square grid (via the Vector tab) using number sliders for the X and Y so that the grid can be adjusted to any size. I then used the points in the centre of each square as the starting point for a circle. I made the radius of the circles controllable using a number slider. I then used the pipe function to make the circles more solid.

{{:fabricademy2017:students:cheung:circles_grasshopper.jpg?500x213|circles_grasshopper.jpg}}

After this, I used the settings below in **Cura** (the program for slicing designs ready to be 3D printed) to print the design on fabric. I had to clip the fabric to the bedplate in order to keep the fabric stationary. I used a slower speed because the flexible filament needs more time to be extruded.

{{:fabricademy2017:students:cheung:cura_print_settings.jpg?300|cura_print_settings.jpg}}{{:fabricademy2017:students:cheung:circles_printing.jpg?300|circles_printing.jpg}}

==== Second design ====

For the second design, I wanted to create a stand alone weave structure. Having no experience in Grasshopper, I needed to use a tutorial ([[http://www.grasshopper3d.com/video/defining-a-parametric-weave|http://www.grasshopper3d.com/video/defining-a-parametric-weave]]) to create a weave. The main steps of the tutorial are as follows:

  * Select Square Grid (Vector tab), add number slider to the x and y directions - so that the size of the square grid (therefore the weave) can be adjusted
  * Create a Cull Pattern (Sets tab, Sequence), with boolean toggle values (Params tab, Special) as input i.e. true or false, and link to a tree Branch (Sets tab, Tree) - in order to isolate different points to then manipulate separately (to create the up and down directions for a weave)
  * Use Move (Transform tab, Euclidean) - to move a row of points up
  * Use Vector Amplitude (Vector tab, Vector) with a number slider - to specify the height of points
  * Use Flip Matrix (Sets tab, Tree) - to flip rows and columns to change the direction of the points (from y direction to x direction)
  * Use Weave function (Sets tab, List) - to weave between 2 points, and using a boolean toggle to change the weaving pattern
  * Use Interpolate Curve (Curve tab, Spline) and the weave function as the input - to create curved lines between points
  * Cull again to isolate curves, i.e. the middle curve or the outer curves (of 3 curves)
  * Use Rotate 3D (Transform tab, Euclidean) - to rotate outer curves
  * Copy steps and switch true / false values - to create curves that are inverted/opposite to the original curves that form the basis for the up and down weave structure
  * Use Pipe Component (Surface tab, Freeform) - to change lines (of the curves) into pipes, with a number slider to change thickness

After I produced the weave using the tutorial, I adapted it slightly to experiment with a new design. The change I made to the original design was to mirror the design on top of itself - to create 2 layers of the weave structure. Printing this double structure with flexible filament, I was interested to see the results, how it would feel and what it would be like when pressed together.

I used the same settings in Cura as the previous print on fabric, however I encountered problems with the print. The first layers of the material were not sticking to the bed. I increased the temperature of the bed and also put down some sticky tape to help the layers stick better. The print improved, however, I still had problems. A colleague helped me with this problem by re-calibrating the height of the bedplate so that the nozzle would be closer to the bedplate. This solved the problem and the weave structure was printed successfully.

{{:fabricademy2017:students:cheung:weave_printing.jpg?300|weave_printing.jpg}}{{:fabricademy2017:students:cheung:final_weave_1.jpg?300|final_weave_1.jpg}}

**//Final thoughts//  **

It was useful to experience Grasshopper, however I found the program difficult use. It was hard to me to find the right function that I needed for a design element I had in mind, and to know what input the components required; often, the program produced results I didn't expect. I am aware that my first design is very simple, as I found it difficult to produce a more complicated structure that I wanted.

I am happy with the final products however. The flexible material makes them pleasing to touch and handle. The weave structure is flexible but also firm when pressed; this could perhaps be a useful structure to absorb the impact from movement.