00_FinalProject

a desktop
material machine

I'm really intersted in how detached designers are from the materials and processes of making. We have developed synthetic materials that are further and further away from their base ingredients and machines that bring us further and further away from the act of making . But even though 'digital fabrication' is in vogue in our discipline, we don't understand the tools we us to make. At least I dont!

I'd like to make a desktop material mixer : a machine that'll let me tailor the recipe of a custom material and mix it for me, ready for fabrication.

updated parts diagram

spiralling

And so with that I've decided that my priorities are:

parametric material selection via UI and mechanical mixing
apply heat for better mixing
manual 'pouring' or extruding for molding/casting
add to 3 axis extrusion system

Right now I am shooting for a machine that'll have (hopefully a significant) number of ingredients which I can select via a UI, it can dispense them into a mixer where they will be heated while they are mixed. The mixer will be designed to be detachable and easy to pour the custom material into an externally prepared mold for casting.

What would be really great is to leave room to hook it up to an extruder later. But honestly, not going to worry about that right now!

final design

i was hoping to make something really minimal with minimal materials. Unfortunately I was leaning on 3D printing a lot with the joints and the cannisters. I would like to recycle transparent plastic bottles of some kind next time and only 3D print the funnel/wheel house instead of the entire cannister.

There are only 3 main processes and materials: laser cutting (plywood), 3D printing (joints and cannisters on Sindoh) and cutting metal (copper pipes)

I feel confident about this construction but I am worried that my electronics wont work to do the project justice!

joints and parts

I was a little worried about the assembly of the cannisters given that the wheel had to be inside , which had to be precisely attached to the servo on the outside, which had to be fixed securely and have a good connection to the wires.

I think the way that I designed it made use of 3D printing nicely so that I had bespoke joints to my advantage. This helped me make a fuss-free design.

dry foods dispensers + cat feeders

dispenser system

Most of the ingredients in these bio materials are powders or a courser aggregates. Somehow I had immediately imagined push syringes and was worried about how the best way to dispense powders would be but soon remembered dry food dispensers like the cereal dispensers you find at hotel buffets. There isn't a great use in automating these but I found a lot of people have automated cat feeders with arduino! These will be useful references moving forward:

paddle wheel mechanism

Most of the systems I looked at involved something that looked like this from a patent document for a dry foods dispenser. Automatic cat feeders sometimes have a version of this where the paddle wheel is 'vertical' instead of 'horizontal' but I think this version might be logistically easier to plug a servo to.

Using this, I would be able to translate 'turns' into volume of the powder - this might be a little tricky but absolutely do-able.

time-based controls

revolving door

this video describes an automatic cat feeder made with arduino. I drew out the mechanism they used to dispense the cat food at particular times. Shows mechanism, construction and code.

Here the quantity is determined by the time that the revolving door is 'open'. I think there is less contron in this and it won't be as effective if I'm using powders that don't 'flow' as easily as larger grains.

rotating keyhole

this video goes through the construction of very similar system but the mechanism is quite different. There are two layers with corresponding openings. One surface rotates and when the holes line up the dry food is released.

Quantity is similarly controlled by time but I somehow feel quantity is even more difficult to control here so I am not going to replicate it.

this project is similar but is button controlled and walks through the code and hardware.

paddle wheel feeder

paddle-wheels are the choice for commercial pet feeders, so they must be effective for dispensing aggregate/grains/powders. I think these are more appropriate because volume is determined by rotations instead of time, so it will give more accurate amounts.

The vertical wheel is what is most popular in DIY projects and manual cereal dispensors. I can imagine that this will be best to keep the ingredients moving. A lot of these examples say how difficult it is to construct an anti-clog design this may be why the vertical wheel is popular - because it is best at scooping up the grain.

I can find loads of these examples online:

The horizontal paddle mechanism is common in commercial cat feeders. It relies on gravity to pull the grain into the paddle, which then falls out of a few segments into the bowl. I'm not sure why this isn't more popular but I am also a little nervous that the ingredients would clog up or bottleneck with humidity.

There is just one sort-of example online:

Automatic Pet Feeder

vertical auger conveyor

my biggest concern is that the ingredients will clog or stick with humidity so I need to have a mechanism that makes sure they keep moving within the container or cannister. The most convincing way of doing that seems to be an auger mechanism, but I think this needs some testing.

This is the orientation of augers in the pet feeders but I'm still worried that humidity might make the aggregates/powers stick and clog. I think in this orientation is might be just as effective to use a 'paddle wheel'. I think the paddle-wheel might even be easier to translate into volumes or quantities of ingredients.

I can find loads of these examples online:

I think a vertical auger might be the most effective way to ensure that the ingredients keep moving. It looks like the vertical auger is usually used as a coveyor to move aggregates upwards, I can't think why it wouldn't work the other direction so definitely worth a test!

I can only find one example of a vertical auger online. This just goes through the construction but not the programming.

Dog feeding station

Power + Control

Final PCBs

Powering my four servos was a big problem and with such little time it was difficult to solve. I made this board which integrated the charge/discharge module which we thought might be a power source. I milled and cut the board and it turns out it was a module to control the charge of lithium batteries! I'm going to try and hack the baord to hook up my servos to the variable output supply in the shop.

Although I had spent a whole day drawing up, milling and stuffing a new D21E board to have on display in my final project, I think I make lots of mistakes when I'm under pressure. A trace or two came up when I was trying to fix a little solder error and I just decided I would use my output board.

This board had been bootloaded incorrectly the first time and then had refused to be bootloaded again. After a few weeks Alek had a go and it eventually gave in and was working properly! Frustrating, but I was so glad just to have a working board.

The above board is the hacked charge/discharge module board. I added a pin to the VCC In so that I could clamp on the power clip of the variable adapter in the shop and connected what would have been in the in and out pins of this module. I therefore had 6 ground break outs and 6 power break outs that could host my servos seperately to my controller board.

I would have to connect my power board ground to my controller ground.

just Desktop

code + interfacing

This was the interface I began during the interface week. Calvin helped me debug it when hooking it up to my arduino script. My main difficulty was how to parse out the 4 instructions for my 4 different servos in the code. This was mostly done in arduino but it was also useful to print the values to check the servos were doing the right thing.

interface

//Sasha McKinlay_ How to Make GUI 2021

import controlP5.*;//import ControlP5 library
import processing.serial.*;// allows processing to speak to Arduino

Serial port; //setting up serial

ControlP5 cp5; //create ControlP5 object
PFont font_Title; // Creating Fonts
PFont font_Sub;
PFont font_Button;
PFont font;

void setup() { //same as arduino

size (1000,1000); //window size (width, height)

// initializing serial
printArray(Serial.list()); // prints all available serial ports
port = new Serial (this, "COM7", 9600);// connect to arduino port, whichever Controller is connected to

cp5 = new ControlP5(this); //initialize CP5

//Managing Fonts
font_Title = createFont ("calibri light bold", 30); //custom fonts for buttons and title
font_Sub = createFont ("BaskervilleURW-Reg", 15); //custom fonts for buttons and title
font_Button = createFont ("BaskervilleURW-Reg", 20); //custom fonts for buttons and title
font = createFont("calibri light bold", 12);

// Add Button
cp5.addButton ("Mix_this") //this is the name of the button
.setPosition(375,825) //coodinates of upper left corner of button
.setSize(250,60) //(width, height)
.setFont(font_Button)
.setColorBackground(#231F23)
;

// Adding Text Fields
cp5.addTextfield("T_Ing1") //name of text field
.setPosition(170,700)
.setSize(120,30)
.setColorBackground(#B4B4B4) // set background colour
;

cp5.addTextfield("T_Ing2") //name of text field
.setPosition(350,700)
.setSize(120,30)
.setColorBackground(#B4B4B4) // set background colour
;

cp5.addTextfield("T_Ing3") //name of text field
.setPosition (530,700)
.setSize(120,30)
.setColorBackground(#B4B4B4) // set background colour
;

cp5.addTextfield("T_In43") //name of text field
.setPosition(710,700)
.setSize(120,30)
.setColorBackground(#B4B4B4) // set background colour
;

// Adding Sliders
cp5.addSlider("SliderVal")// name of slider
.setPosition (200,275)
.setSize( 60, 400)
.setRange (0,12)
.setValue(6)
.setNumberOfTickMarks (13)
.showTickMarks(false)
.setColorForeground (#231F23) // set foreground colour
.setColorBackground(#FFFFFF) // set background colour
.setColorActive (#231F23) //set active colour
.snapToTickMarks (true)
;

cp5.addSlider("SliderVal2")// name of slider
.setPosition (380,275)
.setSize( 60, 400)
.setRange (0,12)
.setValue(6)
.setNumberOfTickMarks (13)
.showTickMarks(false)
.setColorForeground (#231F23) // set foreground colour
.setColorBackground(#FFFFFF) // set background colour
.setColorActive (#231F23) //set active colour
.snapToTickMarks (true)
;

cp5.addSlider("SliderVal3")// name of slider
.setPosition (560,275)
.setSize( 60, 400)
.setRange (0,12)
.setValue(6)
.setNumberOfTickMarks (13)
.showTickMarks(false)
.setColorForeground (#231F23) // set foreground colour
.setColorBackground(#FFFFFF) // set background colour
.setColorActive (#231F23) //set active colour
.snapToTickMarks (true)
;

cp5.addSlider("SliderVal4")// name of slider
.setPosition (740,275)
.setSize( 60, 400)
.setRange (0,12)
.setValue(6)
.setNumberOfTickMarks (13)
.showTickMarks(false)
.setColorForeground (#231F23) // set foreground colour
.setColorBackground(#FFFFFF) // set background colour
.setColorActive (#231F23) //set active colour
.snapToTickMarks (true)
;

}

void draw (){ //same as loop in arduino

background (255,255,255); // background colour of window(r,g,b) or (0 to 255)

//making title backing
fill (35,31,32);
rect (200 , 70, 600, 45); // (X, Y, Width, Height)

// rect (560,275,60,400);

// making a title
fill (255,255,255); //text colour (r,g,b)
textFont(font_Title);
text ("The Desktop Material Mixer",325, 100); // ("text", x coordinate, y coordinate)

// making a subtitle
fill (35,31,32); //text colour (r,g,b)
textFont(font_Sub);
text ("INGREDIENTS" , 200, 240); // ("text", x , y )

}

// adding functions to controls

void Mix_this(){ // button sends current numbers to controller
//port.write(720);
println("sent");
float value = cp5.getController("SliderVal").getValue();
float value2 = cp5.getController("SliderVal2").getValue();
float value3 = cp5.getController("SliderVal3").getValue();
float value4 = cp5.getController("SliderVal4").getValue();

println(value);
println(value2);
println(value3);
println(value4);

int SendVal1 = int(value);
int SendVal2 = int(value2);
int SendVal3 = int(value3);
int SendVal4 = int(value4);

port.write(SendVal1);
port.write(SendVal2);
port.write(SendVal3);
port.write(SendVal4);

//println("Sent " + SendVal+" to Arduino");
}

arduino

#include <Servo.h>

Servo servo1; // create servo object to control a servo
Servo servo2;
Servo servo3;
Servo servo4;

int pos = 0; // variable to store the servo position
//int val = 0;
int buttonState = 0;
int val=0;
int val2 =0;
int val3=0;
int val4 = 0;
int i;
int counter = 0;

void setup() {
servo1.attach(5); // attaches the servo on pin 9 to the servo object
servo1.write(0);
servo2.attach(6);
servo2.write(0);
servo3.attach(7);
servo3.write(0);
servo4.attach(4);
servo4.write(0);
Serial.begin (9600); // start serial
pinMode(2, OUTPUT);
pinMode(3, INPUT);

}

void loop() {
buttonState = digitalRead(3);
if (buttonState == LOW) {
digitalWrite(2,LOW);
}

if(Serial.available()) {
digitalWrite(2, HIGH);

val = Serial.read();

for (int k = 0; k<=val; k++){
digitalWrite(2,HIGH);
delay(50);
digitalWrite(2,LOW);
delay(50);
}

for (int i=0; i <= val; i++) {
if (i<4) {
servo1.write(i*60);
delay(500);
}
else if (i>3 && i<7) {
servo1.write(180-((i-3)*60));
delay(500);
}
else if (i>6 && i<10) {
servo1.write((i-6)*60);
delay(500);
}
else if (i>9) {
servo1.write(180-((i-9)*60));
delay(500);
}
}

val2 = Serial.read();
for (int k = 0; k<=val2; k++){
digitalWrite(2,HIGH);
delay(50);
digitalWrite(2,LOW);
delay(50);
}

for (int i=0; i <= val2; i++) {
if (i<4) {
servo2.write(i*60);
delay(500);
}
else if (i>3 && i<7) {
servo2.write(180-((i-3)*60));
delay(500);
}
else if (i>6 && i<10) {
servo2.write((i-6)*60);
delay(500);
}
else if (i>9) {
servo2.write(180-((i-9)*60));
delay(500);
}
}

val3 = Serial.read();
for (int k = 0; k<=val3; k++){
digitalWrite(2,HIGH);
delay(50);
digitalWrite(2,LOW);
delay(50);
}

for (int i=0; i <= val3; i++) {
if (i<4) {
servo3.write(i*60);
delay(500);
}
else if (i>3 && i<7) {
servo3.write(180-((i-3)*60));
delay(500);
}
else if (i>6 && i<10) {
servo3.write((i-6)*60);
delay(500);
}
else if (i>9) {
servo3.write(180-((i-9)*60));
delay(500);
}
}

val4 = Serial.read();
for (int k = 0; k<=val4; k++){
digitalWrite(2,HIGH);
delay(50);
digitalWrite(2,LOW);
delay(50);
}

for (int i=0; i <= val4; i++) {
if (i<4) {
servo4.write(i*60);
delay(500);
}
else if (i>3 && i<7) {
servo4.write(180-((i-3)*60));
delay(500);
}
else if (i>6 && i<10) {
servo4.write((i-6)*60);
delay(500);
}
else if (i>9) {
servo4.write(180-((i-9)*60));
delay(500);
}
}
}
}

Calvin and Laura really saved me when they helped me with my ardino code. Laura and I weren't understanding how to 'add' to our position every time we hit the 'Mix this' button.

When I approached Calvin with the same problem he came up with the best way to bypass it completely!.

Because the servo can only move 180 degree, he helped me figure out a way to map the input numbers from the Gui to positions that made sernse. e.g. 1 to 60, 2 to 120, 3 to 180, 4 back to 120 and so on.

This is just repeated for each servo, making sure to write the correct value to each servo.

3 Servos working with code worked out with Calvin. Responds go GUI, positioning corresponds to integer sent from GUI.

All 4 Servos working in the system without aggregate. I was honestly worried now that the paddle dispensing system wouldn't work!

in the workshop

fabrication + assembly

some parts

I used one sheet of 1/8" plywood from artists and craftsman for about $7 each for the box and the carriage.

The most expensive part of this project (other than the 3D prints probably) was the copper tubing which was about $7 each. I needed two of these.

Some transparent film (usually used for inket printers) for my windows for approx 13 dollars

Hardware was used from the shop but is can be found for very reasonable prices from hardware stores.
4x HK 15138 for $4 each, sourced from the lab.

The aggregates were discarded materials such as coffee grounds and tea leaves.

I used a lot of processes including 3D printing, laser cutting, drilling, metal cutting, assembly with hardware.

machine + assessment

stystem integration

success!

I had triaged throughout the semester and especially in my last week. I decided that my definition of success was a system that could dispense a fine aggregate by a variable amount determined by a user through a GUI.

There are a few wrinkles I would like to iron our for Material Mixer 2.0:

The servo has to restart at position 0 so it throws out some material when it does this. This means there isn't perfect portion control.
I had triaged out a version where there were two paddles in operation: a finer one and a larger one. I would like to fold this back in so that binders (which are usually used in smaller quantities) could be controlled more
The frame I had designed needed a little more cross bracing. My partner helped me add some fishing line to it to give it a bit more rigidity. I had planned to drill it into the base a little more to give it that stiffness. A 'machine' that's this flimsy is definitely not one anyone can take seriously!

The copper pipes as the legs of the elevated cannister carraige and the housing for my wires worked quite well. I didnt' exactly find a way to hind my wiring completely but it's pretty discrete as it is.

I had to improvise where the electronics would go as my 'presentation-ready' pcb board didn't make it and my plans for a power supply changed over the course of the last week ( I wish I had planned this better)!

presentation video

a desktop
material machine

brainstorm

spiralling

questions to answer

final design

joints and parts

paddle wheel mechanism

time-based controls

revolving door

rotating keyhole

paddle wheel feeder

vertical auger conveyor

interface

arduino

some parts

success!

a desktop material machine

brainstorm

spiralling

questions to answer

final design

joints and parts

paddle wheel mechanism

time-based controls

revolving door

rotating keyhole

paddle wheel feeder

vertical auger conveyor

interface

arduino

some parts

success!

a desktop
material machine