Project Development

Project Development: Half-boiled Egg Boiler Project

Our Team's Chemical Device

For the final assessment of our module, our team has been tasked to put the skills we have used to the test to make a functional chemical product. For our group, we chose to do a half-boiled egg boiler.

What made our group want to solve this problem was that... well first, we love food. And thinking back to the number of times where I personally would want a half-boiled egg and failing miserably by getting an egg that is either cracked and becoming a failed poach, undercooked or overcooked is enough to deter me from trying again. We want to be able to make the perfect soft-boiled egg at home consistently, and hence why we set out on this problem.

After doing some brainstorming, we conceived our first design, as shown here:

In this initial design, we designed a boiler where the user places the egg in the basket, presses the start button and the egg will be lowered in the boiling water for the 6 minutes needed for the egg to cook. After the time, the egg will be raised out of the water and the egg comes out perfectly soft-boiled. This was only the very first iteration of the design, however, and it will be bound to change, as seen in the Design and Build Processes below.

Team Planning, Allocation and Execution

Our team consists of:

1.  Uzair as the Chief Safety Officer
2.  Zelene as the Chief Financial Officer
3.  Zhi Wei as the Chief Operating Officer
4.  Ryan Andrew (me) as the Team Leader and Chief Operating Officer

Design and Build Processes

As mentioned earlier, the initial design of the egg boiler had gone through changes before we had started making the product. Our group applied the method of using TRIZ (an acronym that, in English, stands for Theory of Inventive Problem Solving. I like the acronym TIPS too!) In this method, we look at a problem that our product has that gets in the way of achieving our goal.

For our half boiled egg boiler, the main problem we were addressing was not overcooking the egg. This could come about in our first iteration, as when the egg is raised in the basket, the heat has nowhere to go. Air is a good insulator of heat, hence the heat cannot easily escape the egg and cause the albumen (egg white) to overcook. We hence used TRIZ to solve this problem by looking at the engineering characteristics that can help to solve the problem.

After applying the TRIZ method, we have found that the areas of improvement Extraction and Another Dimension. Brainstorming how to apply the changes in these areas was relatively quick, and the changes that manifested from applying TRIZ were:

1.  Removing the egg basket entirely.
2.  Adding a second layer to the egg boiler, where the egg will fall into after cooking. The second layer will house ice that will cool the egg once it is done cooking.

After taking these changes into account, here is the improved design of our egg boiler:

However, difficulties were borne from the new design, especially with having to have a custom container. More on that in the Problems and Solutions section later.

Now for the building process. In terms of the building, we split our team into two halves: Zelene and I were tasked with making the parts that make up the body of the egg boiler, while Uzair and Zhi Wei were in charge of making the Arduino code for our product.

Designing and Building the Maker Uno and Servo Holders (done by Me)

Now, you may be thinking, where are the Maker Uno and Servo holders in the design we just saw? That part will be addressed later in the Problems and Solutions sections later. For these parts, I had to design and 3D print the components that do exactly as their names suggest - hold the servo in place and contain the Maker Uno boards.

I used Fusion 360 to design and make the parts parametrically. I am again forever thankful for having learnt designing parametrically as it has saved me so much time, and I will let you know more on that later. For now, I first had to design a hinged box for the Maker Uno board, with a hole for the USB cable to pass through. I started with defining the parameters I wanted.

I would like to note that the box width and length were actually 65 mm and 70 mm initially, which were just 5 mm of an allowance. I then used the box tool to create a box with the dimensions I needed.

I then cut the box in half and started on the sketch for the hinge.

I extruded the hinges as needed, cut it up into sections and removed the sections I did not want.

Continuing on, I made a sketch on top of the box and extruded the necessary area for the Servo holder.

I also extruded a hole for the wires to pass through.

I then made the top cover of the servo holder and the place to hold the screw for the servo.

Finally, I made a latch on the servo holder that will secure it onto the Maker Uno holder.

You can have a full 360-degree look at the final product here:

And here is a photo of the final product after printing:

Designing and Making the Platform (done by Zelene)

You can see Zelene's blog post here.

Zelene was in charge of designing the platform. She also used Fusion 360 to create the platform and the extruding rods to act as pivot points for the platform to turn about on.

You can see the platform in action here:

Programming the Servo (done by Zhi Wei and Uzair)

You can see Zhi Wei's blog post here, and Uzair's blog post here.

Zhi Wei and Uzair had collaborated to programme the servo so that it is raised when the machine is idle, goes into a horizontal position after the button is pressed so that the user can put the ice, and then lower down once the 5.5 minutes needed to cook is done. The .ino file for the code (which opens with the Arduino IDE) is in the folder linked in the Project Design Files folder below.

Problems and Solutions

As mentioned before, the group encounter problems that prompted a redesign that made our execution easier. The first problem was that after Zhi Wei had designed the initial container, slicing it in Ultimaker Cura resulted in a print time of 1 day and 2 minutes. Since we did not have the luxury of being able to use the 3D printer that long, we had decided to make do with a new design, as shown here:

In this new design, we had made some changes from the previous one. First, the container would be store-bought instead of custom made. We also had made new enclosures to house the Maker Uno board and Servo, which you saw I designed above. We had also changed the way the product works, where instead of dropping the egg and the boiling water in the ice, we were planning to instead drop the ice into the egg and water, as we found that we would not be able to completely water seal the upper level.

Although the design was a lot more feasible, we failed to consider how we were gonna put the platform in the container. This ended up making our design not work in the end :( Hence, we should have considered using laser cutting for the container as it would be able to fit to our exact specification instead.

Project Design Files

This is the final section of this post. If you would like to see any of the files we had made for this project, you can see them by clicking on this link to the Google Drive folder with all the files.