Magic Wand Design + Fab

So many pieces. So many parts. So much testing. So many changes.

Board Design:

(1)

First board design - look at that rats next ughhh … thanks for the help Andy!

(2)

Final design, accelerometer will be cut from this board and placed somewhere else - it was too long to fit on the board in a straight line

(3)

Most recent board with caps in the wrong spot. Added more lines in for cutting. Unsure why the bantam didn’t lift in between cuts on the dimension layer though.

Parts Testing:

got the mac address set up

Blinking light test shows code and libraries I have on my comp are correct

Audio test shows code and component working

Touch test shows code and component working

Accelerometer test shows code and component working (together with touch sensor!)

Circuit Diagram

Board Fab:

Had some initial errors with board fab but they were fixed on second pass… or so I thought.

Used liquid tin in the morning thinking it was going to be nice and quick… nope!

Enclosure plans:

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The final board looks so good! But actually the large cap pads are in the wrong spot - they should be in the 10 and 22uF spots (3), not 100 and 220pF spots (2). I’ll need to mill again :.(

This is where I started to learn a bunch more about the Bantam. As in.. the errors really started to occur. I realized my packages were too big for my board. Then I noticed my board traces were too thin. Then I couldn’t figure out why the thing said no window on when all windows were on (the back one wasn’t actually). Then my comp died and had to be restarted mid job. In total this 4 hours meant I went through 4 boards only to be left needing to do more. My parts didn’t arrive, and I broke 2 bits. Great evening.

Final project materials

I want to make a magic wand. Science + technology, when executed right, is indistinguishable from magic. This is what I hope to create. I think some pathway from accelerometer + microphone input, via wifi enabled microprocessor to a centralized database that runs machine learning scripts on the inputs could be used for a wide variety of automation projects. Think of the things that are super simple that need no more of an input than on or off, up or down, open or close, high or low, left or right, forward or back, on and on.

products required:

microphone + board design + circuits for op amp + noise balance

esp32 wroom + accelerometer example

accelerometer + datasheet

touch sensor + setup instructions

The idea is that the person can touch the sensor, say something, or move the wand to generate a response, these three actions and their infinite possibilities will give users endless control over their Iot systems, without the pain of squinting at a tiny screen for endless hours, or even at all.

This can be enough for me to set up now, for this class. Later perhaps this summer, I’d like to set up the TensorFlow program to intake my training so I can assign my generated actions to programmatic actions. But that will take some time. For now, this hardware will eat up all my time, and likely then some.

EAGLE designs

This was super fun! I kinda love the idea of designing my own paths and board placements from scratch. Especially as later I can even get artistic with it and try to draw images using the paths… but that’s a little deep down the rabbit hole. For now I’m content with getting all three of these together with only one Via. The last one was pretty complex and I couldn’t find a way to reroute it. Luckily one simple via is quite fine and easy to wrap my head around. Also, I did quite like making the paths curvy in the last one.

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1_attiny85_jig - I didn’t resize this board so it looks a bit big with a lot of empty space surrounding the components, made a mental note to do the next design smaller.

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2_attiny85_LED - For some reason wanted to do a vertical design, not sure why. This was a little smaller, but the routes are kind of crazy… made a mental note here to have cleaner more sensible routes for the final design schematic.

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3_attiny85_transistor - The piece with the Via. And the curvy routes. The really S shaped route tool is a bit hard to control without clicking a lot, so I found myself switching back and forth between downward shaped S and upward shaped S curves. Sometimes it resulted in weird clunky areas I guess I forgot to resolve, as in the far left spot. Otherwise though, I like how this board turned out the most of all, especially as it was the most complicated and took some time thinking about specific pieces, as well as continually referencing the electrical schematic.

First post

Got this tiny lil thing soldered together and got a light blinking, not sure why it's blinking at 1/10th time... did the beep test and nothing was short circuited. So small! I also think I did the wrong thing and soldered the ATtiny direct to the board.