Stand Alone Player SAP
Description.
I designed this to have a two fold purpose. Ever since I built my first Otto I was disappointed that it did not speak, instead it squeaked. My goal was to one day have Otto speak using some kind of mini card player. Now all my robots have this DF mini player case installed on them and included in the design of the robots. Some have changed so much, they don't even look like Otto anymore. This special case is designed to work on Otto though.
Introducing the SAP. This player will work with ardunio, or any 5 volt power source. You must format the names on the SD card and I will later explain on how to do this in this project.
What you will need
- The stl files
- A DF mini player ( you can find it here) https://www.amazon.com/Organizer-YX5200-DFPlayer-Supporting-Arduino/dp/B07XXYQBNS/ref=sr_1_3?crid=3TPEC63LJQJAD&dchild=1&keywords=df+mini+mp3+player&qid=1628010015&sprefix=df+mini%2Caps%2C190&sr=8-3
- Some 28 gauge silicon wires of various colors stranded
- WS2812B led lights that are programmable (here) https://www.amazon.com/BTF-LIGHTING-Flexible-Individually-Addressable-Non-waterproof/dp/B01CDTEJBG/ref=sr_1_12?dchild=1&keywords=w2+led+strip+programmable+5v&qid=1628010178&sr=8-12
- If you want just a led or flickering candle led you can also use that as well. You may have to make some modifications to the object your mounting this on.
- Dupont connectors female
- Adhesive cork (here) https://www.amazon.com/LWR-CRAFTS-Adhesive-Back-Sheet/dp/B094XQRDXW/ref=sr_1_25?dchild=1&keywords=adhesive+cork+craft&qid=1628010342&sr=8-25
- Some tiny screws. ( you must figure this out)
- 1) 1k resistor for the yellow wire
- 1) 470 k ohm resistor for the Neo pixel lights.
- Buck convertor or Ubec to reduce the voltage to only 5V
- A 3D printer
- 2 momentary buttons (here) https://www.amazon.com/BOJACK-Pushbutton-Switches-Momentary-Assortment/dp/B07ZBHXBZ4/ref=sr_1_21?dchild=1&keywords=momentary+button&qid=1628012136&sr=8-21
- 1) 40 mm 2w 8 ohm speaker (here) https://www.amazon.com/a15112300ux1550-Diameter-Internal-Speaker-Loudspeaker/dp/B01BB4YMCU/ref=sr_1_4?dchild=1&keywords=40mm+speaker&qid=1628010436&sr=8-4
- You will have to modify the head of otto with a drill ( I will supply you with a pdf schematic of what to drill)
- Soldering skills above average
- Wire nips and a good soldering iron station
- All the basic electronic skills and tools for electronics
- This include, crimpers, cutters, screwdrivers, meters, testing equipment, etc.
INFORMATION
- FRITZINGS (WIRING)
- STL FILES
- ASSEMBLY PICTURES
- FORMATING THE SONGS TO PLAY
- DISPLAY
- PDF (drilling guide for Otto)
FRITZINGS (WIRING)

This is how you would attach the wires to an Arduino board with a Nano attached to the shield. In the bottom link are the fritzing files. If you need them, they are being shared.

Fritzing files https://drive.google.com/drive/folders/1YaLLq8YqvS18PISXGrcUMG-QY38hGtAw?usp=sharing
You must only use a 5 volt power source to power up the DF mini player. You can use a ubec or some kind of step down convertor for dc. You should research you tube for this information.
STL files
Print all the files at the highest resolution for the best look and fitting. Use supports and table adhesion on these prints. You should expect the prints to take about a day to make. You can decide on what colors you want to make your case. The lens cover must be printed in clear PLA for it to work as it should.
(here) https://drive.google.com/drive/folders/1m0HoiC7T0czz-F7WwrBQNAe_dLq7H8CO?usp=sharing
ASSEMBLY PICTURES

Using the picture and the fritzing pictures, you should be able to figure out how to correctly solder the wire leads to where they go. You should also have a decent skill of soldering at this level before you take this project on. Once you have all the wire soldered in place and the correct resistor installed on the yellow wire. (It should be a 1k resistor)

You can use the above picture as a guide. Showing on this picture is how I used toothpicks as shims for the DF mini player. You should also note how I positioned my wires through the case to the button case. I recommend you don't use any glue on any of the electronic parts at this tiny of a level. It can really mess your components up as I have learned the hard way and short things out. Instead you should use adhesive cork to hold everything in place. It works really good and holds it it nice and tight.

Each picture explains itself



You need to pay special attention to how I snaked in the wires from the DF mini to the speaker. It is very important that you do it as the pictures show. There are little recesses that are designed to make this an easier task.

The next picture shows it all assembled, you may have to do some drilling and fitting to make sure it is assemble correctly.


The neo pixels will only work with a programmable board. They won't work on just a plain power source. You should test out your new player with a simple 9 volt battery that has some kind of ubec or buck convertor installed in between the DF mini and the connector. Remember you can only use 5 volts no more or no less. You can use this player pretty much anywhere there is a 5 volt power source. Below are some examples of how I used mine on various things I created including the "shorty" Otto.


The sound chambers in these designs maximize the most potential of the little speaker. I am told by those who have listened to these say, it sounds very clear, and loud with no distortion at all.
FORMATING THE SONGS TO PLAY
The DF mini plays back files directly from the SD card but it has a limited folder and file naming scheme. To use mount the SD card onto a PC and copy across the folder tracks with their original naming (e.g. albums for folders and track names for files).
If you have used the DF mini, you should know that the filenames of sound files must be named "001.mp3" "002.mp3" and so on, then you must copy them as .wav files, copied to the SD card and then you can play them by their number.
One would think that the DF mini reads the file names but that is not true. When you copy mp3 files with any name, it will still happily play them, but you do not know the order. Truth is, that you need to rename the files, so they got copied in the right order, because the DF mini does not read the names, it simply lists the directory. You can find more about this doing a you tube or internet search for this information.
DISPLAY
You can use Neo pixels, as long as they are programmable, or led's. You just need to figure out what you want and how you want to mount them. I will supply you with the lens cover, it is up to you to decide to what you want it to show.
PDF (drilling guide for Otto)
If you plan to mount this to any Otto you should use the drilling guide that I made to show you where and what size holes you should use to modify the head. I am supplying this template for you to use. It should fit most original and newer otto heads.
(here) https://drive.google.com/drive/folders/1-TfE11SVQm8qMsSRSYzsZNgzu9I892co?usp=sharing
DISCLAIMER
If after reading this you decide this is too much of a task, you can email me and I can work out a deal with me to make one for you. You must provide the shipping costs and be patient if you live anywhere else besides the united states. I am not guaranteeing anything on this article nor the components you would buy. But I will tell you I would build one for you, and test it out before I send it out. There would be no returns and any payment back for loss of any mail. I would only build these for those who would pay me using Paypal. If this interests you please tell me so in the comments along with your email.
I hope you enjoy this project as much as I had making my robots speak, play music, and show off some displays.
Demonstration of the quality of the sound chamber.