BLOG 4: GRAND FINALE
Updated: Feb 25, 2025
Hello and welcome back to the final entry in this line of blogs. This time I'll be taking you guys through the chemical device that we've made.
It is the ultimate culmination of everything we've learned so far. Arduino programming, 3D printing, and designing are among the other new skills we've learned over the long and arduous journey of bringing this idea to life.
OUR CHEMICAL DEVICE
So what is this elusive highly impressive chemical device I keep mentioning? It is an automatic plant-watering device system that ensures that a plant is consistently able to have an adequate amount of water at any given point in time. According to statistics published by BetterPlanter about 50% of all houseplants die due to a lack of consistent or under-watering and many of these houseplant owners feel guilty for having plant blood on their hands. So in an effort to reduce negligent plant homicide, we came up with a product to solve these issues. Our product employs moisture sensors, gears, and a submersible pump all easy to source and cheap components, so if you really wanted to you could replicate this at home. Here's a sketch of the final prototype of the product that we envisioned. Alongside an embedded 3D model of what it actually ended up looking like. We titled and named our product Aquatomate a fusion between the words Aqua for water and Automate for the function of the prototype.
Pretty neat if I do say so myself. But the journey is far more beautiful.
THE AQUATOMATE-TEAM
As they say, Rome wasn't built in a day and certainly not by one person. And the same goes for our product. None of this prototype would have been possible without each of my fellow group members putting in their best efforts.
The handsome bloke in the red shirt is our CEO (Chief Executive Officer), Nicholas. In charge of making big decisions and ensuring that we stay on task and that things are done up to a standard that we all can consider acceptable. The lovely lady in black is our CSO (Chief Safety Officer), Zhi Ling. In charge of ensuring that whenever we do something we always prioritise safety above all else and that our product as a whole is safe for use. The dashing lad in the black shirt with a surfer on it is our COO (Chief Operations Officer), Kynan. He's in charge of actually executing the planned tasks and reporting issues or challenges back to the CEO so that we can reroute or adjust accordingly. And lastly, we have me (Hasnain) in the cream shirt and I was tasked as the CFO (Chief Financial Officer) of the team, ensuring budgets are being utilised appropriately and optimally as well as purchasing and sourcing materials for the project itself. Despite these fixed roles we continued to be flexible in the tasks that we assigned one another as each of us is unique and has certain skills that may be more useful in other tasks. For instance, despite being the CFO I played a pretty big role in the designing physical assembly aspect of the project. And this flexibility honestly worked to our benefit.
Now that you've met the team let me take you through our plans.
First of all, we had to come up with a bill of materials. As CFO I naturally stepped up and began putting together an Excel sheet with links to each component that we required. Always choose the cheapest or most cost-efficient components, trying to recycle and make use of existing materials in the lab whenever possible given that we only had $100 to work with in total. In the end, we managed to scrape by with about $20 spare in case of any emergency purchases.
Below is the finalised bill of materials with all working hyperlinks should you desire to replicate or improve upon our prototyped design.
BILL OF MATERIALS (BOM) | ||||||
|---|---|---|---|---|---|---|
No | Description of item | Link to Purchase | Quantity Needed | Unit of Measurement | Unit Price (S$) | Total Cost (S$) |
1 | Container | 1 | L | 1.24 | 1.24 | |
2 | Moisture sensor | 1 | pcs | 1.79 | 1.79 | |
3 | Arduino Maker Uno | 1 | pcs | 12.86 | 12.86 | |
4 | 3d printing filament | 1 | kg | 13.99 | 13.99 | |
5 | ½ inch PVC pipe | 3 | m | 2.73 | 5.46 | |
6 | 5V Submersible Pump | 1 | pcs | 1.90 | 1.90 | |
7 | Micro 360 Degree Continuous Rotation Servo | 1 | pcs | 5.00 | 5.00 | |
8 | Power bank 20000 mAh | 1 | pcs | 15.90 | 15.90 | |
9 | 3 Way PVC Pipe | 4 x 12mm (ID) | mm | 0.12 | 0.48 | |
10 | Acrylic Sheet | 500 x 500 x 5mm | 5mm | 7.45 | 7.45 | |
11 | Relay switch 5V | 1 | pcs | 1.07 | 1.07 | |
Grand Total Cost: | $67.14 |
Now that we've planned out all the things we need to buy and acquire we must also plan out what to do with them and when to do it. We're all busy students after all so having an organised schedule with people assigned to their tasks would be ideal. This is where our Gantt chart comes in handy. A Gantt chart, invented by Henry Gantt sometime in the 1910s (yeah something that old is still useful today. Crazy huh) is a bar chart typically used to illustrate a project schedule. Detailing vital information such as the duration allocated to each task on the vertical axis, the person in charge of said task, and what tasks to perform in what order. Using our own finalised Gantt chart as a reference.
We can see precisely how we can expect the workload to progress over the weeks. When planning this chart we took extra care to take note of public holidays such as Chinese New Year or other commitments that members had so that we could plan around them. After all, Getting enough rest and taking time off is also a crucial part of ensuring a project goes well. I opted to help out mainly with the programming and the documentation but as I mentioned earlier these allocations were mainly as a supervisor to ensure that the tasks actually got done. We honestly had to be flexible and switch roles to save time but ultimately if you were in charge of that certain task you are entirely responsible for getting it done. Even if you needed another group member's help to do so. All in all. I think this Gantt chart was really handy in ensuring that our prototype was done on time and not rushed. Honestly, we did not stray too far from it and were pretty stress-free towards the submission date of our prototype a first. So yeah the Gantt Chart is really useful.
DESIGN AND BUILD PROCESS
Oh man, this was harder than we anticipated. Our design and build process can be put into 3 big stages.
STAGE 1: LAYING THE FOUNDATIONS
In this stage, we were just focused on tackling the biggest tasks. As we intended to reuse some PVC pipes as a support structure to build our prototype around we spent a significant portion of the first few weeks learning how to use a saw and other hand tools to size down 2-meter-long PVC pipe into 30cm lengths that we could join together to form the frame. At the same time, we had to start designing the 3D-printed mechanical gears that we would be using to rotate the plant about a point so that we could achieve even watering of the soil.
Another thing that we had to start tackling was the wiring and programming of the code into a functional state. Certain components such as the relay and pump required that we pick up new skills like soldering as well as just generally figuring out how a relay works and how we should be wiring it. Thankfully most of this stage went smoothly and we could then move on to stage 2 which was just cobbling everything together and seeing if they worked as well together as they did individually.
STAGE 2: INTEGRATING EVERYTHING INTO A GREAT BIG BOX
Stage 2 was about starting to put everything together and see if it just works. As well as refining our mechanism's design
Obviously, it didn't "just work" and many adjustments were made. During this stage, we started to build the walls around our foundation using our cardboard joinery skills to ensure stable and strong support for our plant.
During this stage, we were also able to start testing the actual feasibility of our mechanism as our circuitry and Arduino components were seemingly working expectedly. So with the help of some blu-tack and an acrylic plate, we did exactly that.
And it worked! Sort of at least, I'll let you be the judge just see the video below.
Yeah, we still have a ways to go...
STAGE 3: FINAL ROUND
Stage 3 was about making the final few adjustments to get everything working together. This entailed readjusting the mechanism.
After many failed iterations and various adjustments, we came up with this final design and it did work as intended. But only after two failed prints.
After doing a small-scale test as to whether the newly adjusted base could support the weight of our potted plant without toppling over. We finally were happy enough with it to glue things down. Below are two videos demonstrating it working.
My Contribution
Despite being assigned to oversee the Arduino code and the documentation of our project I ended up spending most of my time assisting with the 3D design for the project, coming up with the initial designs for the gear mechanisms as well as any future adjustments. I ended up doing this more as I proved to be surprisingly adept at designing things in fusion especially when given feedback to implement into the design from my team members after each iteration of the mechanism or the base.
PROBLEMS AND SOLUTIONS
Developing our product was definitely not as smooth sailing as the earlier section has made it out to be. We ran into so many problems that just had us banging our heads against a wall trying to think of a solution and it is honestly the biggest source of stress during this whole journey.
PROBLEM 1: BUSTED PUMP
The first issue we encountered was a pump that just wouldn't turn on no matter how we wired it, we tested it in all sorts of ways trying to figure out where our circuitry or programming went wrong but in the end, we just tried to run some power through it to see if it would even turn on. Only then did we discover that the pump itself was not functioning. So, the solution was to just source another pump.
As simple as this solution appears to be it highlighted the importance of ensuring that you test each component of your system before integrating it into a bigger system as lots of time could have been saved if we had just done a simple test to ensure the pump would function under normal circumstances instead of jumping straight into connecting everything and just hoping that it'll work altogether. PROBLEM 2: LIMITATIONS OF A SERVO MOTOR Given that servo motors are only able to turn 180 degrees we had no way of using just the servo to rotate the whole plant 360 degrees. So to solve this we incorporated our mechanism of two gears. We designed two gears such that the gear ratio between them is 2:1 so that when the driver gear turns 90 degrees the larger gear can turn 180 degrees giving the smaller gear full access to 360 degrees of rotation using the 180 degrees of rotation available to a servo motor. Furthermore, we also had to fine-tune the speed at which the driver gear would spin so that it wouldn't spin so fast as to throw the other driven gear off its post. This was achieved through painful trial and error. PROBLEM 3: HOW TO SOLDER???? Another big problem that we encountered is that none of us had ever soldered before and we had to if we wanted to use the submersible pump in our circuit. So being fully capable chemical engineers we sought help from the world's greatest teacher, the internet. With the help of YouTube videos and our helpful Technical Executives to provide some advice and pointers we were able to acquire this new skill of soldering. And ultimately able to implement the pump into our circuit. Here's one of the most helpful videos we found on soldering.
DOWNLOADABLES You can get all the project files we used for this at this link :)
REFLECTIONS
Honestly, I don't know where to start with the reflection on this blog let alone to try and sum up my whole experience this past semester, but I'll try my best to make it coherent. Firstly, the biggest and most important realisation I've had during this journey is that theory is way easier and simpler than reality. To know how concepts work theoretically is a world away from knowing how to apply them, but it certainly is the first step in getting there. A prime example of this during this project is the design of the mechanism utilising the gear ratios to achieve the desired full 360 degrees of rotation Another thing I've grown a sense of appreciation for is good hand skills. Granted, it is very intuitive once you understand the general idea of how to use them but it definitely is more challenging than it seems to transform a sketch into something tangible and feasible. Something that you can feel and touch. Something that doesn't look like it was made by a five-year-old left alone with a set of crayons. Something that you can be proud to put your name on. This obviously only occurred to me after we put together our own prototype cause aesthetics were definitely not the first thing on the priority list. Nonetheless, we had opportunities to hone our skills using new tools such as saws, files, and even a soldering iron. Every project has its ups and downs and typically these ups and downs are not part of the initial plan. These unexpected challenges that show up serve to build another vital quality every engineer should have. Adaptability, solving problems as they arise while maintaining the course for the final goal of the project is a skill that takes time to develop, and during my own time it felt more like improvisation rather than adaptability but I definitely did get a feel for it during my time in this project. LASTLY, the most important thing I've learned about designing and maybe about life in general is that FAILING IS A GOOD THING. Only when you make a mistake do you glean a deeper understanding of why certain things happen under certain circumstances. Hypothetically, if you somehow came up with a plan that is executed perfectly and produces a perfect result you would grow less than someone who had a not-so-great plan but spent the time to work his way through it to attain the same perfect result because not only did he achieve the same result he also has the experiences of his failures to grant him that deeper insight into why and how his plan or design worked. I think this frame of mind can be applied to many other things in life and honestly helps to reframe the fundamental perception of failure in a more positive light focusing more on the growth it brings rather than being so preoccupied with the outcome of whatever pursuit you so chose to pursue.
THE END
AND THAT IS A WRAP FOLKS. It has been a very challenging long and arduous semester and boy am I glad it is over. I think this time around I definitely did achieve all 3 of the goals i set for myself at the start of this blog series. I'll put them below as a reminder. Goal 1: I want to grow even more competent with my hands-on skills and put my theoretical knowledge into use in a meaningful way Goal 2: I want to learn to see the world through a more "engineering" tinted set of glasses,
Goal 3: HAVING FUN WHILE I LEARN!
Yeah, I definitely have begun to bridge the gap between theoretical and practical hands-on skills. The prototype we've made is tangible irrefutable evidence of that. Considering that the only reason this evidence exists, to begin with, is because I bothered to put on my big-boy engineering pants and work with my group to come up with this I can say I have started to see the world with a more engineering perspective frame of mind.
Finally, despite all the challenges my group has faced and our feelings towards the outcome we've arrived that I think the one thing that every one of us will attest to is that we definitely had fun doing not just this prototype but the whole module as an entirety.
Learning a blend of both theoretical and practical skills. For instance, the design of the experiment and understanding of mechanisms I believe will definitely come in helpful next year alongside the improvements we have made to our Arduino programming prowess I am sure will come in handy somewhere further down the road.
Lastly, I want to thank everyone for taking time out of their day to read this incoherent mess of ideas words, and sentences strung together with no helpful format to help the readers. This last blog felt like a massive milestone and achievement and looking back at it now I feel it lacks quite a bit of the distinctive wit and character that my other blogs have but I suppose that is a result of the growth that I have undergone this semester.
I WISH EVERYONE READING THIS THE BEST IN ALL THEIR FUTURE ENDEAVOURS. GOOD LUCK FOR EXAMS MY FELLOW STUDENTS AND THAT IS ALL.
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