Shopping

solar panels and polycarbonate sheets

Yip Wan Ting Shopping 0 Comment

The last component we needed to settle was the power source. Currently, we have been drawing power directly from the socket, but in order to make the boat travel freely on its own, we would need to give it a kind of portable batteries.

Which required reading of labels I would never have noticed until you were intentionally looking for them. 

We learnt about input and output voltages and currents, how DCs and ACs are used in real life appliances. Turns out, most of our appliances take in the same measurements of current and voltage, and it wasn’t the data we were looking for either… 

After a while we figured out where to look for the data, and then we were able to calculate the total voltages and current needed. 

Tony suggested instead of building a battery out of scratch, we could consider solar panels which would give the boat this rechargeability element, and it was a great idea in that now it was “self-sustainable”, and utilizes the natural energy from the sun!

We found out that this technology actually came from the idea of photosynthesis, and studying the components of chlorophyll — finally, a word that is familiar. 

Its quite interesting to see how biology is applied in the engineering scene. 

So after trying out different positions of the solar panels on the boat, we figured the best way was to place solar panels flat on top of the raft to capture the most sunlight. 

Which also meant we had to get the dimensions of our boat.

We also decided how to attached the observational camera at the bottom, and under Tony’s guidance and experience, he suggested using an acrylic board held by aluminum profiles to extend the camera further below the boat so that the view is not blocked. 

So it was another round of shopping for us, purchasing boards, aluminium profile brackets, longer cables and solar panels.

 

Continued

Yip Wan Ting Brainstroming, Shopping 0 Comment

Apparently, there were some miscommunications. The guys expected a larger diameter of the pipe, and Tony, well let’s just say Tony didn’t expect us to purchase the pipe at all. In the moment, it was a sense of helplessness and frustration.

Tony was confused as to the mechanics of our boat. That session, we learnt what the PVC pipes were for: stability. One on each side, not on all 4 sides due to the unstable nature of the box. The PVC pipes were meant to be used to prevent capsize, if the pipes were longer than the box. Putting PVC pipes as a lifebuoy would not help with stability at all. 

Moreover, the box we purchased was too buoyant. The high volume ratio meant that little water would be displaced when put into a pool, something we greatly overlooked. We only considered buoyancy, and having made rough calculations, we decided to play super safe in getting a large box such that it would be able to float. While we thought we had settled the issue of not floating; we failed to consider the other extreme: too much floating! 

“Then how?”

Anita took it all in stride. “No blaming. We are a team.” She was a role model and her moving forward mindset carried the disheartened us forward. We gathered together and discussed the next steps. What if we bought a smaller box? What if we used a swimming board? Can we get ideas from other boats? How about that previous project on the ‘Underwater Drone’?

It felt like we were back to the drawing board; like we took a sprint forward, but only to realize we had to go back to the starting line. But as Zheng Xun rightfully pointed out, “we are better now than we once was, nothing was wasted.” It was all part of learning, you win some, you lose some. 

And though it was not the ideal experience, it was a fruitful and lesson filled one. We came together as a team,  instead of falling apart. We took into account a lot of other considerations: first buoyancy, now stability, and then in the later part, mobility. It wasn’t easy, but we sat ourselves down and came up with many drafts and drew many rafts (yes I am a poet now)… 

Sketches and Workings

After discussing for an hour, we came up with a second draft and presented it to Tony. Anita our spokesperson made the meeting light hearted albeit the initial downcast atmosphere.

Though he was rushing home, he stayed back to help us figure out a compromise and how to move forward from here. 

Armed with a way forward, we were slightly more optimistic and had a better direction on how to proceed for the next meeting! 

Yet another long and tiring day, that paved way for the next.

Make-shift lifebuoy

Yip Wan Ting Shopping, Tinkering 0 Comment

“I tell you so many [university] students come to me before one… I tell you what to do…” -Boss of Bes-Gro Enterprise PTE LTD

Anita and I agreed to meet at IMM. But I was running late, so Anita had kindly already gone to purchase the 55L container from Giant by the time I arrived. Carrying the bulky box from IMM to the next bus stop under the hot sun got us drenched in perspirations by the time we arrived at the next stop: Bes-Gro Enterprise PTE LTD

  

the place was definitely any engineer’s dream, it had all possible tinkering supplies — from industrial scale torchlights and spades, PVC pipes and wires… and a buzz of truck drivers littered around the perimeter getting their pre-purchased goods. Everyone knew what they were doing there, they came with a mission and purpose — and honestly, so did we, but we still stood out like tourists in a sea of locals. 

Sunlight filtered through the clouds, and it was all very idealistic and dreamy — until the reality of not really knowing enough engineering mechanics hit us. What to tell the person at the counter?

We didn’t have to grab his attention, because it was only a good 10seconds of hesitation before “Ah girl ah, what you want?” prompted us to speak. 

Showing him the containers and describing the essence of our project as comprehensively as possible, he proceeded to prompt us further. Where will the pipes be? What are the pipes for? How are we planning to attach the pipes? What is the design like? 

Bombarded and at a loss, we showed him the image of our model and the blueprints. 

“Something like this-“

He ponders, and proceeds to reply:

“I tell you what; you do like that.”

The uncle whips out a pen and draws something similar to this design; describing how the PVC pipe will float if connected like a lifebuoy. 

And thinking this is a great solution as well, we bought it. The idea, and the materials. He gives us 2m worth of PVC pipes, 4 elbow connectors and PVC Brian Glue to stick the PVC pipes together.

The following scene spelt an incoming problem: 2 short and blur students stranded in the middle of nowhere — ie. Jurong Industrial Centre — with a 2m long PVC pipe, a maze of large container trucks and previously struggling to handle 55L containers on the bus led us to one logical conclusion: Private Hire. (update: thankfully, Dr Ho was kind enough to allow us to claim the money from the transport back)

With that, our next destination was NTU; where the guys were busy cracking their heads coding and discussing software matters, familiarizing themselves with Blue Iris and the RPi module.

To be continued.