Assignment :
Design and produce something with a digital fabrication process
(incorporating computer-aided design and manufacturing) not covered
in another assignment, documenting the requirements that your
assignment meets, and including everything necessary to reproduce
it.
This week is something different. This is the time to try something that we never done before
I am a greate fan of Anouk Wipprecht and her wonderful dynamic dresses.So I wanted to design something that couid impart a dynamic nature to our fasion.
I wanted to create a hood that automatically changes its appearance with respect to the wantings of it's user. It needs a lots of painstaking stichings and gluing . But am excited about the end result ,So i decided to do it.
I have no idea wether this will work or not. But i decided to have a try in fusion 360.
We need to be a little carefull while designing.
Remark! I Tried some miniature versons to finalize the design.
The assembly of all the functional components is a painstaking procedure .We need to be more patient and conscious while assembling the components.
Marking all the componets with identification number will reduce any future errors.I placed all componets in a flat surface inthe proper order .Then I connected them with masking tape with proper overlapping. After connecting all together connect each strip with nylon thread.hold the threads in place with a piece of tape . after completing the threading we can remove the supporting tape pieces .I tested the structure with an aluminium rod as the shaft.It worked perfectly.
Then I laser cutted a supporting base structure in accrylic.It is always preferable to have a test cut in cardboard or papper to ensure the diamensions.
I decided to use NodeMCU for my project .So that I could avoide a lot of wiring a simple app in app inventor could replace a lot of wiring.The app itself is so simple .It has a text box where i can write the IP address of my device(NodeMCU) and 2 buttons for opening and closing the hood.
This article from Medium.com discuses about the integration of nodemcu with MIT app Inventor.
For programming NodeMCU for a biginner this Instructables page I found much helpful.
I just modified an example code provided with the esp8266 board manager It is available in File -> Examples -> Esp8266 WiFi -> WiFiWebServer
I added a function to controll the servomotors while a esponse will get from the android app.
#include <ESP8266WiFi.h>
#include <Servo.h>
#define LEFT 5
#define RIGHT 4
Servo left;
Servo right;
int pos = 0;
const char* ssid = "jogin";
const char* password = "12345678";
WiFiServer server(80);
void setup() {
Serial.begin(9600);
delay(10);
// prepare GPIO2
pinMode(2, OUTPUT);
digitalWrite(2, 0);
// Connect to WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
// Start the server
server.begin();
Serial.println("Server started");
// Print the IP address
Serial.println(WiFi.localIP());
left.attach(LEFT);
right.attach(RIGHT);
right.write(173);
left.write(7);
}
void loop() {
// Check if a client has connected
WiFiClient client = server.available();
if (!client) {
return;
}
// Wait until the client sends some data
Serial.println("new client");
while (!client.available()) {
delay(1);
}
// Read the first line of the request
String req = client.readStringUntil('\r');
Serial.println(req);
client.flush();
// Match the request
int val;
if (req.indexOf("/gpio/1") != -1) {
val = 0;
Serial.println("offff");
for (pos = 170; pos >= 7; pos -= 1) {
left.write(pos);
right.write(180 - pos);
delay(15);
}
}
else if (req.indexOf("/gpio/0") != -1) {
val = 1;
Serial.println("onnn");
for (pos = 7; pos <= 170; pos += 1) {
left.write(pos);
right.write(180 - pos);
delay(15);
}
}
else {
Serial.println("invalid request");
client.stop();
return;
}
// Set GPIO2 according to the request
digitalWrite(2, val);
client.flush();
// Prepare the response
String s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>\r\nGPIO is now ";
s += (val) ? "high" : "low";
s += "</html>\n";
// Send the response to the client
client.print(s);
delay(1);
Serial.println("Client disonnected");
}
The end result looks like this
Android App apk
Lasercut File 1
Lasercut File 2
After completing my hood and while sharing my experiences with my instructures.They said that I had to use a new manufacturing process in this week . Actually I got confused because I was suppose to make something with a robotics arm like 3d print food or plastic with an extruder attached to it But I thought it says I had to make some robotic things with digital fabrication.So I decided to make a small composite also.So lets start the process .
A composite material is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure, differentiating composites from mixtures and solid solutions.
The new material may be preferred for many reasons: common examples include materials which are stronger, lighter, or less expensive when compared to traditional materials.More recently, researchers have also begun to actively include sensing, actuation, computation and communication into composites, which are known as Robotic Materials.
For this week I decided to make a small flower vase using linen fabric and epoxy resin
I designed my vase in autodesk fusion 360.
This is my design
Since I designed a not much complicated design .I decided to use the laser cutter for creating my mold.I stacked 7 pieces of 6 mm acrylic to make my mold.
While designing the mold I put a 5mm hole in the center of each piece .It helped me to stack each piece correctly using a 5 mm metal rod.I used Super Glue to keep the individual pieces in place.
I also used laser cutter to cut my fabric.I layed the fabric on the laser cutter bed and focused with the focusing tool'
I set origin a few distance away from the corners so that i could get a flat surface and also reduce the entangle ment of fabric with cutting head.
I selected the settings for cardbord for cutting the fabric.
It cutted all required pieces perfectly.
These are the essential parts of a vaccum bag
Vacuum bag film This is a polypropylene film, modified to resist elevated temperatures. The elastic nature of the film offers high formability and resistance to puncture, also permitting the film to be stretched over complex moulds without need for a large number of tucks and folds, so improving the efficiency of the vacuum. The film is suitable for use with prepreg and wet-lay-up laminating systems.
Breather/bleed fabric This is a 5 mm or 10 mm thick uncompressed felt of temperature-resistant synthetic fibres, treated with mould release. The material has good drapeability, allowing use with large and complicated mould patterns. It can also be used as a bleed fabric to absorb excess resin from wet lay-ups.Perforated release films These are made from modified polypropylene and can be rigid (recommended for use on flat or uncomplicated mould surfaces) or elastic (thin and stretchable, for large complex moulds with the need for tucks and folds). The films have good mechanical properties and performance at elevated temperature and are naturally self-releasing, treated on one side to assist adhesion to the breather fabric or a protective film.
Tacky tape This is a butyl-based vacuum bag sealant giving high elasticity and tenacity. It has exceptional sealant properties, eliminating the risk of imperfect seals often found in the initial phases of vacuum bag application, so improving the vacuum efficiency and reducing labour. It is suitable for polyester, vinyl ester and epoxy laminating systems.
Release Film Basic purpose of the release film is to ensure the proper release of the helping material use for vacuum bagging. Release Films are placed directly in contact with the laminate. They separate the laminate from breather/bleeder fabrics, which have no release characteristics.
This is how we stacked layers for making the composit.
Cover the mold material with Release Film .I manually cutted the pieces with a pen knife.
I used Easy Cast Transparent Epoxy Resin and it' having mixing ratio of 100A:50B and the curing time is about 24 hrs.
Safty first, Wear gloves to protect our skin from chemicals.
1st place the glass on the weight scale and re calibrate to set that as zero. Then measure 50 mg part A and then set the scale to zero again .Now measure 25 mg of part B on the same galss. Mix the resin thoroughly.
Gently sock the fabric inthe resin and lay alternatively .1st lay the vertical pieces and then the horizontal pieces. Apply 2 or 3 similar layers above it .
Place the mold and composite on the preset vacuum bag.The bag shoulg be prepared befor mixing the resing . It will ease the vacuuming process to suck excess resin from the composite.
place the composit above the base of vacuum bag .Then place the perforated filim above it . Place the Breather and Bleeder layer above it . At last seal the bag by placing the top of vacuum bag.
Connect the vacuum hose to the bag and start the vacuuming(I used vacuum cleaner for this).
I let 24 hour for the composit to cure.Carefully remove the composit from the mould and trim the excess material.
This is the final outcome.
Design files