PCB Design

One of the more important things to do between demo days was the development of a PCB that could house all of our circuitry. With 32 motors and LEDs planned for the final product, condensing everything was very important in order to make a display that not only looks nice, but that does not take up unnecessary space with ugly wires.

Baseline Demo Day

Today we had our baseline demo and it went as really well! Many people liked our project, including Rahul, Sid, and Parth.

We had a little bit of a panic before our actual demo because after setting everything up with my laptop, the display was reacting incredible slowly, and we still have no idea what was going on. We ended up having to use the Raspberry Pi, without testing stuff on the laptop because for some reason the display was much more reactive using the Pi. However, the Pi started acting up as well. The library we used to communicate with the Kinect, libfreenect, suddenly wouldn't connect with the Kinect and would throw an error that none of the suggestions solutions could solve. After repeatedly killing the program and retrying, we finally got it to run and didn't touch it for the remainder of the demo day.

This is something that really needs to be looked at before the final demo, these kinds of issues shouldn't be happening.

After our demo we talked to Rahul about our reach goals. We decided on the following reach goals:

1. Bigger display (6 x 4)
2. Audio Interaction
3. PCB
4. More advanced hand tracking (incorporate more depth)

Almost Final form

Here's a nice clip showing off our almost fully completed project (created automatically by Google Photos):
https://goo.gl/photos/SyYrKWrHZT31GpRS8

Organizing Wires

Here is the display pre-consolidation:

Note that the servo wires are not attached in this picture. That's another 48 wires to add to that heaping cloud of copper.

Here is the result after soldering many connections together and organizing the (now connected) servo wires.

Mass Production

After working with our 3 cubes for a few days and working the kinks out of our algorithms, we were ready to make the rest of the necessary cubes. This post is dedicated to pictures and information about that process.

Laser cutting:

Assembly:

After many hours of manufacturing, assembly, finding issues, disassembly, more manufacturing, more assembly, etc, our project assumed its final form (laptop for scale):

Attaching lighting

With all the flickering issues gone, it was time to solder the LEDs to longer wires and attach them to the boxes. Using red as Power, black as Gnd, and white as Din/Dout, this is what a few of the LEDs looked like:

After attaching them to the central rod of each box, this is what we were left with:

Through the magical use of electrical tape and hot glue, we managed to get each of them attached, while hiding the ugly wires from view.

Further LED issue

The video in the last LED post is not of the greatest quality, but the LEDs were flickering a noticeable amount. Given that we did not know the WS2812 in and out, we couldn't determine the root cause of this at first, but we googled and googled until we came up with..........nothing that worked. The only fix we found was to lower the voltage to 4.5 V from 5 V, but we had already done this earlier when the LEDs did not want to cooperate with us.

So, the magical fix is................a capacitor from power to ground. That was it. Flickering gone. Yay hardware.