My iteration project was built as a stepping-stone from my newly-acquired Arduino skills to my final project. To do so, I built a box with a map of my local area on the front, and a number of LEDs that lit up at 13 different bus stop locations to indicate where certain buses where.
before we dive into the process, here’s the final result:
The three lines near my house are green, gold, and silver, as pictured above.
My previous project for Arduino was a strip of NeoPixel LEDs that could be controlled using a joystick:
This iteration project began with a sketch of some ideas I was considering:
Option (A) was the one I decided to construct, with the integrated LEDs. Option (B) would have involved a sort of clock/timer with rotating servos to indicate approximately when the next bus would arrive. Options (C) and (D) involved using LCD screens, which were a little too advanced for what I was looking to work with for this project.
To design the front of the box, I found a site call snazzy maps that could modify the look of google maps to be whatever I wanted. So I took a screenshot of my local area with just the roads visible and converted it to an SVG for the engraving process. I then found a different online tool to construct the SVG files for my wood-engraved box.
I was initially looking to use individual LED bulbs for each bus stop, but if I wanted to use a multicolor LED, I would have 4 pins on each bulb, and 13bulbs in total… so I decided to change my approach and use NeoPixels. Since I was primarily concerned with accuracy on the map for the bus stops, I hadn’t considered the troubles I might experience when attaching NeoPixels to the board. this resulted in a bit of a haphazard setup, with the NeoPixel strip contorted in order to line up each hole in the board:
I then went over to the Makerspace and learned how to solder! I tried looking at a few youtube tutorials to help me along, but it was still quite a time-consuming process. I asked Niel about how he goes about soldering, and he showed me a technique that involved applying solder to each component separately, and then bringing them together and heating to attach them securely. This made the process much easier, and I was able to successfully attach all of the neopixel strips together. In particular, I made sure that I had the data line all heading in the same direction to avoid trouble later down the line.
Now that the LEDs were setup, I began programming the device! Since I would need to connect to the cuMTD servers to get bus data, I decided to use a Wifi-enabled Arduino. I then installed Postman onto my laptop so I could test my API calls to MTD, and then implemented them into the arduino code once I felt confident.
I ran into some trouble when making API calls through the university wifi, as they likely have security measures in place. With that said, the project is working successfully at my apartment! Here’s the code I used, which utilized a mix of NeoPixels, HTTP requests, and WIFI connectivity code:
Some issues that I was facing with the implementation is that random LEDs would light up for colors that I haven’t even programmed in, as seen here:
My best guess as to the source of this problem was due to power surges in the data signal for the LEDs. After getting access to a resistor and a capacitor, I was able to mitigate this issue.
Here’s a video of the final product in action: