Blog 5

Hello everyone, sadly this will be my final blog for CPDD. Thankyou for joining me on this wonderful journey and I hope you guys have learnt many meaningful insights with me. In this final blog, I will be documenting the project development of my chemical device.

Our team Chemical Device

Let me introduce you to my team chemical device 'BrewStars' 

Brief description:

BrewStars revolutionizes tea brewing, ensuring every cup is perfection. It blends tea leaves and monitors temperature, guaranteeing optimal flavor extraction. As the population ages, many elderly individuals contend with musculoskeletal conditions like tendonitis. Since most elderly love tea, the process of brewing can pose challenges, particularly with manual stirring and lifting heavy teapots. BrewStars addresses these concerns by incorporating an impeller for effortless tea mixing and a tap for easy tea dispensing. This design aims to reduce strain and minimize the risk of injury.

Initial Hand sketch:

Final Hand sketch of the chemical device:

To come up with such ideas to create BrewStars, you definitely need a team and in this section I will be talking about

Team Planning, allocation, and execution

Let me introduce you to my team, as the CEO a.k.a big boss of the team we got Jing Yue. As the money man a.k.a CFO is me, Yu Jie. As the COO a.k.a overseer of the team we got Mabelle. Lastly as the CSO a.k.a safety man we got Dhasna.

After thorough planning, we came up with the Bill of material (BOM) and Gantt chart

BOM with links to all items:

BOM.pdf

Download PDF • 60KB

BOM: 2

Gantt Chart:

Here is a simplified version of the Gantt chart

Design and Build process

In this segment, I will be sharing how my team and I designed the teamaker and built it from scratch. From the Final sketch and BOM provided above, you can roughly guess what items are needed to be 3D printed or Laser cut. Feel free to join my team on our designing process!

Part 1

Design and build of impeller and impeller gear (Done by Mabelle)

Mabelle Blog

Part 2

Design and build of Gears and Gear board (Done by Dhasna)

Dhasna Blog

Part 3

Design and build of Box (Done by Jing Yue and Yu Jie)

Jing Yue Blog

I assisted with the laser cutting and the learnt that we could actually use makeabox.io to generate a box .dxf file in just 5minutes! instead of doing it from sketch on fusion, which took Jing Yue 2 days to complete...

video of laser cutting:

Part 4

Programming of Arduino (Done by Yu Jie, Mabelle and Jing Yue)

The implementation of Arduino is to rotate the impeller when a minimum temperature of 40 degrees celcius is read. By doing so, my group decided to use a temperature sensor to constantly monitor temperature and a 360-degree spinning servo to rotate the gears which would simultaneously rotate the impeller,

Below is the code that commands the temperature sensor to constantly read temperature and when it reads a temperature above 40 degrees celcius, it will send a signal to the 360-degree servo to start spinning,

#include <OneWire.h>
#include <DallasTemperature.h>
#include <Servo.h>

#define ONE_WIRE_BUS 9

OneWire oneWire(ONE_WIRE_BUS);

DallasTemperature sensors(&oneWire);

float Celsius = 0;
Servo myservo;
const int Ledpin = 9; // Changed Ledpin to const int
int temperature = 0;
int pos = 0;

// Define minTemp as a global variable
float minTemp = 20; // Corrected minTemp threshold

void setup() {
  sensors.begin();
  myservo.attach(9); // Attached servo to pin 9
  pinMode(Ledpin, OUTPUT); // Initialize LED pin
  Serial.begin(9600);
}

void loop() {
  sensors.requestTemperatures();

  Celsius = sensors.getTempCByIndex(0);

  Serial.print(Celsius);
  Serial.println("C");
  
  // Control servo motor based on temperature
  if (Celsius <= 20 && Celsius != -127) { // Changed to use minTemp variable
    for (pos = 0; pos <= 180; pos += 1) { // goes from 0 degrees to 180 degrees
      myservo.write(pos); // tell servo to go to position in variable 'pos'
      delay(15);
    }
    for (pos = 180; pos >= 0; pos -= 1) { // goes from 180 degrees to 0 degrees
      myservo.write(pos); // tell servo to go to position in variable 'pos'
      delay(15);
    }
  }
  else {
    // Do something else when temperature is below threshold
    // Turn off LED when temperature is below threshold
    digitalWrite(Ledpin, LOW);
  }
}

Setup for Arduino:

Originally, we planned to utilize a micro servo for rotating the gears. However, upon running the code to achieve a 360-degree rotation, I discovered that micro servos are limited to a maximum rotation of 180 degrees. Consequently, I opted for a DC motor as an alternative. Unfortunately, the DC motor proved too fast and impractical for our purposes. Subsequently, I settled on using a 360-degree servo instead.

Video of evidence that i had put my blood and sweat into this programming:

Part 5

Integration of all parts and electronics (Done by everyone)

As you can see from the final sketch, our chemical device is designed in a way where he Arduino setup and gear train will be located at the top of the container. This is done so by gluing the acrylic box on the cover of the container, such that it can house both the arduino and gear train. While setting up the arduino, we realised that only one ground port was functioning. This made us perform extra tasks like soldering. Here is an overview of our integration:

Hand tooling

1.      Soldering

-       Soldering of wires to temperature sensor

-       Soldering of wires to create a modified wire as Arduino Board only have one available ground port

2.      Hot Gluing

-       We had to hot glue the sides of the box together and had to hot glue the box to the cover.

3.      Assembly

-       Servo and driver gear are positioned perpendicular to the gear board so that there is enough space for the gear train.

-       The impeller is immersed to a depth two-thirds of the container height.

-       Temperature probe is partially submerged in the tea.

-       Gears are configured to function as a small speed multiplier.

Enjoy these images:

Final Product:

Problems and solution

Problem 1: Insufficient Ground ports (we needed to use 2 ground port but only one ground wire port was functioning)

Solution: We used the soldering iron to solder 2 male wires to another male wire to create a 2-port splitter. Such that we can connect both ground wire for servo and temperature sensor into one ground port

Problem 2: Arduino Programming and Setup (temperature sensor was constantly reading -127.0°C and servo wasnt spinning)

Solution: We had to troubleshoot the same code with different setup and vice versa till we got the servo to start rotating and temperature sensor to start reading accurately. We also got assisance from our fellow classmate Yu Chen, who helped us with the setup and fixing the code.

Problem 3: Assemblement of the gear train (The gear train was asymmetrical, with some gears positioned at different levels)

Solution: We used cardboard to create an elevation for the servo and driver gear to perpendicularly rest on, and we also used folded paper to elevate the driven gear such that the height is in equilibrium.

Problem 4: Assemblement of acrylic box (The dimensions of the sides prevented us from assembling the box as initially planned)

Solution: We had to modify how we assembled the walls of the box together. We had to stick 2 of the walls on the inner side of the box and the other 2 on the outside.

Problem 5: Water leakage (Tap was not fully secured onto the container)

Solution: We hot-glued the sides of the tap so that when the hot glue solidifies its acts as a barrier so that the water will not leak out and be contained.

Project design files as downloadable files

In this segment I will provide all the design files:

Arduino and Fusion Files

Below is the learning reflection on the overall project development

Throughout this journey in CPDD and ICPD, Im proud that I was able to apply what ever I have learnt onto this project development. It was really a hectic 3 weeks of prototyping as we had to focus on our other modules as well. But thankfully, we had a Gantt chart to guide us on our time management. The BOM was really useful aswell, as it made sure we plan whatever we need for the prototype before starting the prototyping. Ensuring no time wasted in getting neccesary resources. Being as CFO also made me think strategically on how to finiancially manage the budget. Which could also benefit me in the future.

As the person in charge of Arduino, I would like to rant that I have spent more than 10 hours on troubleshooting and testing out codes for the Arduino to function as expected. Without the help of my team members, I feel that the Arduino will forever be incomplete. Although programming the Arduino is fun, it frustrates me when so much time is wasted and we havent gotten a single progress on the code. For example, during the 3hr in the LAB, Jing Yue and I were troubleshooting different codes but couldnt get a single one to work as planned.

During the design and building process, thinking of a way to use implement the gears was really tough as adding it in would make things more complicated. But since it was a criteria, we had no choice but to use it. Thankfully we had many experiences in using Fusion360 and 3D printing, so creating the gears were no problem. Similarly for Laser cutting. However this time, we had to operate the EpilogPro instead of the

Universal660 laser cutter. This made me gain more experience in learning how to operate new equipments. As for 3D printing, I got to learn how to start up a 3D printer by inserting the filament and also heating up the plate.

I am grateful to have this team with me throughout this whole module, as everyone has their own strengths. Which helps benefit us in solving different problems and completing certain tasks. With Jing Yue as the CEO, we were able to finish everything on time as he arranged several meetings to make sure things are done when it is supposed to.

There are definitely some room for improvment. For instance, as the CFO, I should have check what items were needed in the BOM. As we had to make a new purchase after submitting the final BOM. In addition, I have to also improve on my coding skills and doing the wire setup of the arduino board and bread board.

In conclusion, this experience was a fruitful one and I am blessed to have these teammates in my group.

I do hope I can apply this project development skills on my FYP or even in my future projects. I also managed to learnt some new technical skills such as starting the 3D printer, operating EpilogPro and some basic wiring for the Arduino.

THATS ALL FOR THIS BLOG, THANKYOU FOR STICKING WITH ME TILL THE END.

SPECIAL THANKS TO MY WONDERFUL TEAM CONSISTING OF JING YUE, MABELLE AND DHASNA