Week 3: More Testing and Building (and Breaking?)

Mechanical

This past week we finished all the printing and laser cutting for our chassis! We left off last week having completed the tank and the main pot, but this week we were able to finish everything and see them all together! The image below shows all the parts for our chassis which is mostly printed with help from WatiMake. In terms of the printing, most of the parts were printed with ease, except we did have some issues with some of the smaller and thinner pieces. Because of this, we were required to reprint one of them, but seeing as we are estimated to be well below budget, and the price of the piece was very cheap, this was not a hassle. Additionally, some sanding was required to give our chassis a nice smooth finish like seen below.

Testing into the waterproofness of the tank was also going to be performed sometime next week. We received all our parts and had a meeting with our professors last week who brought up the importance of waterproofing our tank. While the gasket should provide us with 100% waterproofing, and the tank is completely separated from the inside of our pot, more rigorous testing will be performed to ensure no water leaks into our electronics.

Software

In terms of software, this week we tested out our IR sensors. We had to do some more investigation into how to wire the sensors and what resistors were needed because this was a newer concept for the team. After some tinkering with our parts, trying a handful of different resistors, and blowing up one of our LEDs (oops) we figured it out. By using our photodiodes (black LED) as IR emitters and phototransistors (clear LED) as receivers, along with 10K resistors, we were successfully able to detect objects/surfaces with our Arduino Mega. This was a good start for the team as the code can easily be integrated into the rest of our finite state machine. A few tweaks to the threshold values in our code (to determine if we've detected an edge or not) will have to be performed once we put the entire product together.

The two pictures below show the wiring and setup for the test with the IR sensors. Additionally, the video shows the IR sensors working real-time detecting a piece of paper.

The team also investigated the capacitive touch sensor a little bit more. This sensor would be used for determining the water level in the tank, to see if the user needed to refill it. We were in the process of wiring and hooking it up when we realized that we forgot to order an integral part... the copper tape :( Because of this, we had to put testing this sensor on hold. We did however find the correct tape we needed on Amazon and would be ordering it sometime this week. This would cause a small delay in testing, but with prime we knew the tape would come soon! In the meantime, we plan to put together the test code and solder the pins onto the capacitive sensing breakout board so when the tape comes we'll be ready.

Other

This week we wrap up the first version of our website and prepare for official launch tonight (official as in we have to submit our website link to our professors tonight). We hope that what we have right now will be enough to excite website visitors about our project! As we progress through building our system we plan to slowly add more details to our website including pictures, videos, mock-ups, and more so stay tuned!