This blog will cover my team's chemical device, our team planning and allocation, our design and building process, problems and solutions, our downloadable design files, and finally my reflection.
Our team Chemical Device
· In this section, I will briefly describe my team chemical device.
· What it is. What problems will the chemical device solve?
· Below is the hand sketch of the chemical device.
Background:
Tea is the most consumed beverage in the world. Cultures like Japanese culture even have tea ceremonies. Tea is a beloved drink that many enjoy. People drink tea for many reasons. For its calming effect, the flavour and its benefits to our health. Hence, we wanted to create something that they would enjoy and use practically.
Our objective: To achieve an ideal cup of tea in a convenient manner, by using a tea brewer machine for the user to enjoy.
It is required that the process is safe and the machine is compact while easy to use.
Overall ensuring user-friendliness and better quality of life for user.
My team is making a tea maker. But it isnt just a simple tea maker, it's a lifestyle. We wanted to make something that tealovers would find convenient, while also making a perfectly brewed cup of tea. It works by sensing the specific temperature of the tea that it needs to be brewed at, and then lowering the tea into the cup and allowing for an optimum brewing time. Once the brewing time is over, a tune is played and the teabag rises.
We made it specifically for black tea, which is the most consumed tea around the world.
The problem our device will solve is the inconvenience of brewing a perfect cup of tea. If a user did not have our device, they would need to manually measure the temperature of the water and time the brewing duration.
Team Planning, allocation, and execution
· In this section, I will list down my team member's name and their respective roles (CEO, CFO, COO, CSO)
· I will show the finalized BOM (BILL OF MATERIALS) table.
· I will show the finalized Gantt chart (planned and actual) and the tasks allocation for each team member.
Below are our roles:
CEO - Leader of the group
CFO - Maintains finance
COO - Maintains organisation
CSO - Maintains safety
Below is our BOM:
Below is our Gantt chart:
Below is our task allocation:
Design and Build Process
In this section, I will provide documentation of the design and build process.
We developed our final design and sketch after many trials, using systematic design and TRIZ.
From our final sketch, as a group we first decided to create a cardboard prototype based on our chosen cup's size, to help us check whether our idea was feasible, with the opening placement for the servo and temperature sensor.
Thankfully, all the measurements worked well. After we decided on the design. Hong Yi worked on the Part 1: CAD and lever for 3D printing, Cheryl worked on the Part 2: laser cutting, and Kieron and I worked on Part 3: the programming. We then worked on Part 4: integration all together.
Part 1. Design and Build of CAD and Lever (done by Hong Yi). Link to Hong Yi's blog:
Part 2. Design and Build of laser cutting (done by CHERYL) Link to Cheryl's blog:
Part 3. Programming of servo and temperature sensor (done by Kieron and ME). Link to Kieron's blog:
Below is my documentation of programming:
To start off this programming, Kieron took the temperature sensor and I took the Servo. To get the basic code for the servo, I went back to my arduino programming pre practical which included my codes.
Once I had the basics, it was difficult for me to work without both electronics, so i went to the internet to find out how to code the two electronics together. I came across this website https://www.instructables.com/Temperature-and-Servos/ , which I thought would help me. Hence, I applied the code from the website and tried to tweak it to our product's function. So I went ahead to tinkerCAD to help me work with what I had, only the 360 servo.
However, since our temperature sensor was not available on tinkerCAD, the code didnt actually work on our temperature sensor when we met up to try it out. So after that, we decided to take the 2 electronics home in turns. We decided what the code would do and in what order:
With the basic code of the temperature sensor from kieron, we added in the servo code in the void setup and void loop respectively, as well as the code for the music which I also referred back to my pre practical for help. I ensured that the codes were in order.
Through many trials, the code worked in the end. However, through the many versions of the code, each code was very similar to each other. Just a bit of tweaking was needed.
Below is the code:
Before void setup, we include all necessary libraries, and establish all variables for temperature sensor, servo, music played and the loop to go once.
Void setup included establishing connections, and establishing the servo as attached to pin 9.
Void loop first included the code for the temperature to be read and shown on the serial monitor.
This string of code helps the code loop only once each time the board is reset.
The aFunction() sets the runOnce flag to 1 and it won't ever run again until the device is reset due to the if statement inside loop().
Under void aFunction, everything here loops once. This code shows that when the temperature displayed is 60 degrees celsius and above, runOnce =1, means the loop is done and wont happen again. The servo moves from 120 degrees to 50 degrees in a duration of 30ms. and remains at 50 degrees for 180000ms for the brewing time.
After 180000ms, the melody here plays according to the duration.
After the sound is played, the servo moves from 50 degrees back to 120 degrees in the duration of 30ms, and remains at 120 degrees for 3000ms just in case.
If the temperature is not = 60 degrees celsius or above, the servo stays at 120 degrees.
After I got the code working, I took a hero shot:
Part 4. Integration of all parts and electronics (done by ALL)
· Embed the finalized fusion 360 design files.
· Documentation for integration.
· Hero shot for integration.
For the integration, we had to glue the acrylic parts, insert the electronics and glue on velcro to make the top and base detachable.
Here is cheryl acrylic glueing:
Here is us testing out the servo in the acrylic panel that holds it:
We then neatly placed at the boards and wiring into the base and pillar, and glues the velcro onto the base and cover of the base:
Here is our final product :)
Hero shot:
CAD :
Demonstration:
Problems and solutions
In this section I will describe the problems encountered in the design and build process and how the team solved them.
For the code, there were 3 main problems:
· Problem 1 and how we solved it
For the first issue, all we had to do was ensure all the strings of code were in order, based on our steps we wanted the code to do. In the end this helped the code to work.
· Problem 2 and how we solved it
For the second issue, we thought the delay was the issue, but it was actually that the bracket for one part of the code was not sectioned off well, affecting the delay of the servo. Hence to fix this we just went through each line of code, and ensured each bracket had its partner in the correct position until we found the outlier.
· Problem 3 and how we solved it
For the third issue, we thought the best solution was to code for the loop to go once only. Hence, I did some research and found this website which helped the code loop once, fixing the problem: To Loop Once .
· Problem 4 and how we solved it
For the last issue, we had problems with the lever diameter, and getting it to fit and stay on the servo. To do this, we tried many different sizes of the diameter, going down each time. However, the lever would still come loose. Hence, hong yi thought to make a hole through the diameter where we can insert a screw which would help keep the lever attached to the servo no matter what, we then also changed the kind of servo so that a screw would be able to hold on nicely.
Project Design Files as downloadable files
In this section, I will provide all the design files (Fusion360 files, .dxf files, .stl files, arduino programs files) as downloadable files.
(upload these files in onedrive or google drive of your personal account. Each person must have these files. Always check that the links to download the files are working.)
Google drive containing all the files : CPDD Group 3
Arduino programming;
CAD & 3D Printing:
Laser Cutting:
My Reflection
This project definitely was a tiresome one, but I did learn a lot from it. Not just how to code, but more on teamwork, team dynamics and how to overcome problems, which I suppose is an important aim from the project. The whole project started with choosing which device we wanted to create. We thought that a tea maker might be slightly easier, but also quite interesting to make. Boy were we wrong about it being easy. During the planning stages, we always had to keep in mind how our final product would look and that we could just put anything on paper because it would need to be executed in the end. This meant we could not be very ambitious as we are amateurs. I learnt that the planning was for sure the most important part and once done properly, everything else would fall into place. We learnt that before even starting the designing, we should finalise the size of the cup, because all the measurements revolved around it.
When it came to the designing, I chose to take part in the programming because I felt that it was really cool and honestly i find it very fun especially when the code turns out right. At first Kieron and I split the parts, me with the servo and Kieron with the temperature sensor. This part was easy as we had already undergone coding for servo, I just needed to change the angles. However, at first we bought a 360 servo thinking we could control its angle. Turns out we can only control its speed. This taught me to do my own research on things before getting them :(. After doing our individual codes, we came together and took turns working on the code to get both parts working together coherently. It took us many hours to get the code right, but it was worth it because without the code, nothing would work literally. Coding once again taught me patience and to not give up :). After doing the basic codes, it was difficult to put the two codes together. Many issues arose, such as the temperature readings being wrong, lever angle being wrong, and other small issues we wanted to fix to perfect the teamaker. Overall, it took a great amount of effort.
After all our parts were completed, we came together as a team to assemble our product. This part required some thinking as we needed to figure out what acrylic parts to glue first so that the wiring was not touching any acrylic glue. Hence, we learnt strategizing was important when it came to small things like this. We also did not want to glue the whole thing as we wanted to easily access the arduino board in case anything happened. So we adapted and figured to use some velcro to make it detachable. After this, our product was done and everything fit perfectly.
All in all, the project was a good lesson and showed us how difficult things can be, but if you put your mind to it, it can be done and done in a fun way. I learnt a few new hard skills as well, such as acrylic glueing and coding definitely. Some soft skills I learnt were communication, teamwork and adaptability. Interesting journey overall.