PRACTICAL 1

In week 3, we attended our very first practical lesson for this module. This practical was named "Reverse Engineering" and this is how it went.

🧰 What did we do in this practical?

Throughout this entire practical, first, we dismantled a coffee maker and find out the different components in it.

Such components are the heating element, which heats up the water supplied to the machine, the plastic white tubes that are used to carry water through the entire machine, and also orange rubber tubing, one of it was a normal orange rubber tubing that is used to carry water throughout the entire machine and one was actually a check valve that the machine uses to stop backflow of tainted water back into the water tank in the coffee machine. 

An example of how a check valve looks like is shown below in the image provided.

This is one of the more major discoveries we have found about the coffee machine as we did not know that there is such a pressure system that might cause a backflow of the liquid, thus such a valve must be used.

Here are some pictures & time-lapse of how the entire dismantling process.

Secondly, we also carried out an experiment on energy transfer from the electrical power input to heat energy output to make the coffee. We used measured amounts of water and coffee powder to make a cup of coffee and we then used the information collected to calculate the efficiency of the system.

💬 How did the team do the practical?

First, as a team, we assigned different roles for everyone such as the team leader, timekeeper, researcher and technical executive. One of our teammates had to take up more than one role due to our shortage of members as we only had 3 members as compare to other teams which has four. Despite the lack of manpower, we were still able to coordinate our actions and thoughts to ensure that everything is done with efficiency and quality.

Secondly, we managed to utilize our time well due to our timekeeper and team leader doing their job responsibly. We provided constant reminders to inform our teammates about the teacher's progress as compared to ours.

Lastly, we listened to Dr. Noel and the lab technical executive attentively and made sure we follow their instructions carefully to ensure that there will be no possible rooms for errors.

👀 What worked and what didn't work?

We learnt a lot throughout this entire practical as it was our first time doing such an experiment and we did not know how to dismantle certain equipment. However, we managed to improvise in certain scenarios although there were mistakes made in the process as well.

👍 What worked for us

1. When we were dismantling the machine and removing the screws, some of them were hidden deep down inside the machine and it was difficult to get them out even after unscrewing them. Thus, we thought of using pliers to grab them out instead so that the screws will be taken out and kept well so that it can be installed back in after.

2. We used masking tape to ensure that all screws taken out from the machine are named such that we would know where should it be screwed back when reassembling.

3. When the water in the water tank is used up, the power supplied will be cut off and time should be recoded. However, there was still a lot of water that retained in the filter and has yet to be filtered out into the jug. Therefore, to not let this situation affect us, we recorded all of the values that should be known down first and we waited for the coffee in the filter to slowly filter out, thus we can get an accurate measurement of the actual amount of coffee brewed and the amount of water that retained in the filter and spent coffee beans.

👎 What didn't work for us

1. When we were reassembling the machine back together, we were met with some problems as certain components could not fit in its original position. Thus, we had to ask for help from the lab technical executive to help us with certain re-assembly parts. After much struggle, we managed to piece the machine back together.

2. Dr. Noel told us to come up with plausible mass and energy balance equations to use for our calculations using the values we recorded during the experiment. However, we were unsure of the variables that were available for us to make sure of, thus this caused a confusion in the group and we could not sort out the correct equation that we should use. The matter was made worse when the team had different and distinct opinions on it. Thus, we had to ask Dr. Noel for advices on how we can tackle this problem.

3. At first, even after research, we could not find out how did the electricity consumption meter work as we were not sure if the power when being supplied to the machine would have significant changes that might affect our calculations in the later parts of the experiment. We actually wanted to take down as many different values as possible throughout the entire duration of the experiment and find the average power input from it. However, when we turned the machine on and there was a reading on the meter, we realized that the reading on the meter do not change the way we thought it will. Thus, we ended up taking the most appeared reading on the meter which is 730W.

OKAY THAT'S THE END OF THE BLOG ENTRY!!!