PComp Project 3

Idea Sketch & Inspiration

I wanted to do something with a physical output for this project, and I really liked the video Yeseul showed us in class of the automat toolkit by Dada Machines.

So my original idea was to do a physical drum machine, using a similar drum head from the video, maybe a cowbell, or a triangle. I played with the idea of either doing a digital interface on P5 or a physical interface like buttons or a Playstation controller.

A basic sketch below is what I thought it could look like and an example of a digital interface.

While I was looking at the materials I would need, I decided to do glasses of water and spoons instead because it would be significantly cheaper. Plus, I like the idea better of having six glasses all tuned to different notes with the amount of water in them.

While I was home over break, I bought a bunch of spoons from Ikea and had my step dad help me drill holes into them so that I would be able to mount it onto a servo motor.

The sketch below is what I’d like the layout of the servos / spoons / glasses to be in.

My thought is to have six glasses of different amounts of water tuned to C – D – E – F – G – A. And what’s great is that if I want to change the tune I can simply just change the amount of water. I will also have six buttons correlating to each ‘note’ as well as a couple of preprogrammed buttons that will play a tune.

I think I will call this project SPOONS. Very creative, I know.

Below is a bill of materials and rough production schedule.

I started by making sure that I’d be able to mount the spoons onto the servo motors.

When purchasing the servo motors, I had thought they’d be larger and closer to the model we’ve been using in class. They’re pretty tiny, BUT luckily the servo motors have so far managed to hold up and operate as I’d intended.

And of course I had to test that the little servo could handle the spoon.

Before jumping to six servos and buttons, I started off testing with three.

Next, I moved on to rigging up the three spoons to three glasses of water and I also programmed one button to play a series of notes. Nothing a little cardboard and gaff tape can’t handle.

So, I spent about half an hour one afternoon trying to ‘tune’ the glasses to a C, D, E, F, G, and A… only to discover that the glasses I have purchased will tune to a highest note of G flat at best. Which eliminates my ability to have an A. The highest note it tunes to is a kind of sharp G flat, so I’m going to use it to pass as my G note.

Next, I’m planning out the layout of all the glasses and motors/spoons.

I then mounted the (now) five servos to a small strip of wood in a straight line, just so I can finish programming everything and testing.

The video below I’ve gotten all five buttons to play each note/servo correctly.

I then moved on to programming a few buttons to play an entire melody. It’s been a bit tricky finding sheet music that only uses C, D, E, F, G.

When coding this, I also wanted a better / cleaner way of writing the songs. So what I did was made functions for each of the notes, called them individually for their individual buttons, and that way it made it much easier to code the tunes, instead of copying and pasting several lines of code for each note, I simply just had to call the function and space the notes with a delay.

A lovely (automated) rendition of Jingle Bells.

The third servo as you can see in the video spazzes a little, I need to try and fix that. I’ve since replaced the motor, but it seems to still do that more than the others, I’ll look into it.

Also, on my quest to find songs that only use the five notes I have, I figured I should just add a B below the C and bring my number of notes/motors back to my original intended six.

Next, I’m going to fabricate the center mount for the motors, solder everything onto a PCB, figure out the wiring, and also the interface. I still haven’t decided if I wanted to just use buttons or make some other type of user interface.

So originally I wanted everything to be in a circle, but I figured creating the center mount would be easier if it were just straight rows. I also like the idea better of being able to see directly into the middle of everything.

After building the mounts for the servos, I worked on moving everything to protoboards. I need to have a separate protoboard under the platform where the servos are on, and from the protoboard it needs to connect to the Arduino, and I need a second protoboard in the user interface enclosure for the buttons which will also connect to the Arduino.

At the start I was mounting everything onto one protoboard, and soon realized I needed the two separate ones. On the PCB for the servos, I solder on dip sockets so that in case a servo needed to be replaced, it would be easier to swap them out.

I purchased screw terminals for the Arduino Uno, because it felt more sturdy and reliable than just popping the wires into the dip sockets on the Uno.

After finishing the servo proto-board, I tested it with my breadboard that still had the buttons from before.

I ran into an issue where two of the servos wouldn’t work. At first it was the second and third, then it changed. I tried reseating the header pins and making sure the connections were secure. Eventually it started working, I’m not exactly sure what the issue is, but I’m pretty sure it was how the servos were seated in the dip sockets.

I then worked on building the enclosure for the buttons and mounting everything, and hot gluing all of the panels together.

I then tested the buttons with the servos after everything was transferred onto proto-boards. And lo and behold — ISSUES!!!

The four buttons programmed to play songs weren’t working. So I looked all over the board seeing if anything was disconnected, or shorting, only to finally discover that I forgot to connect the power lines to the power bus from the Arduino that everything else is on.

Once I soldered those connections, I tested it again and all 10 buttons worked, thank god! The last thing to do was to finish assembling the enclosures. As a precaution, because I had a weird issue with a couple of the servo connections, I taped them securely to the header pins on the proto-board with some electrical tape.

The last step was to safely walk it to the floor and play-testing in class!

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