Introduction: Portable Wrist Mounted Raspberry Pi

Hello everyone,

Welcome to my first tutorial on building a wrist mounted Raspberry Pi.

I am a huge fan of wearable technologies and I thought it would be a cool idea to create a wrist mounted computer for my Robotics class project.

My initial idea for this project came from a guy named "314creator" (here is the link to his original work: https://314reactor.com/2017/03/01/windows-98-wrist... ).

With some modification to a design I create my own version of wrist mounted computer.

Step 1: Components

  • Adafruit PiTFT 2.4" HAT Mini Kit - 320x240 TFT Touchscreen (Preferably go for 2.8 instead of 2.4)
  • Raspberry Pi 2 or better
  • Micro SD card (16GB or higher)
  • Lithium Polymer Battery (1000mAh or higher)

  • PowerBoost 500 Charger - Rechargeable 5V Lipo USB Boost @ 500mA+

  • Micro USB cable

  • Car LED strip lights

  • Galaxy S7 Edge Armband, MoKo Sweatproof Sports Armband Exercise Running Arm Band Case for Samsung Galaxy S7 Edge, with Key Holder, Great Earphone Connection, Black

Step 2: Establishing Power Supply

In this step, we will be connecting a PowerBooster 500 charger to a lithium Ion battery.

Here is a step by step guide on installing a power supply.

https://learn.adafruit.com/adafruit-powerboost-500...

(Note that you won't need to buy any addition switches, because PowerBooster 500 comes with a included switch)

Step 3: Attaching a Touch Screen

Attaching a screen can easily be accomplished by simply lining up a touch screen holes to Raspberry Pi pins.

Step 4: Installing an Operating System

Now before we install any Operating System into a Raspberry Pi, we first have to format the Micro SD card.

Most Raspberry Pi could come with a pre-install program in a Raspberry Pi, therefore it is a good idea to completely format our micro SD card.

To format, you will need to have a desktop or laptop that have micro SD card slot, or just buy a Micro SD card adapter.

You will first have to download a software called SD card formatter. (Here is a link that I used: https://www.sdcard.org/downloads/formatter_4/)

Next, you will need a Win32 Disk Imager (here is a link that I used: https://sourceforge.net/projects/win32diskimager/)

Once you have both of these software downloaded, plug in your SD card to your computer and start out by choosing a SD card drive. It is important to not mess up this step, because if you choose a wrong driver it can potentially wipe out your entire driver. (As for me, my SD card driver showed up as E driver.) After selecting a driver, just click format.

Next step is choosing a Operating System, here is a download link to the image / instructions (https://learn.adafruit.com/adafruit-2-4-pitft-hat-...)

Once you download the image file, boot up Win32 Disk Imager.

Choose a image file and select your SD card as your device. Finish it by clicking "Write" button.

Step 5: Configuring Your Raspberry Pi and Touch Screen

Afterwards follow these steps (https://learn.adafruit.com/adafruit-2-4-pitft-hat-...) to complete your configuration.

You can do these steps with a touchscreen attached, or just connect your Raspberry Pi to a monitor.

As for me, because I couldn't connect to a monitor for some reason, I used a attached touchscreen to complete my configuration.

Either way is fine, but I found out that using a touchscreen to configure a Raspberry Pi was much difficult, as you can see from the picture the resolution were out of place.

If you choose to work with a touchscreen, be sure to go to sudo nano /boot/config.txt. This is where you can change your touchscreen resolution.

These are some of the default code:

[pi1]
device_tree=bcm2708-rpi-b-plus.dtb

[pi2] device_tree=bcm2709-rpi-2-b.dtb

[all] dtparam=spi=on

dtparam=i2c1=on

dtparam=i2c_arm=on

dtoverlay=pitft28r,rotate=90,speed=32000000,fps=20

Try to adjust some of the numbers to fit your resolution.

Step 6: Final Step, Putting Everything Together

For this step, watch a video I made.

Samsung S7 case link: https://www.amazon.ca/MoKo-Sweatproof-Exercise-Ear...

[Some things you can try to improve upon my project]

  • Better way to hold Raspberry Pi and touch screen together (sometimes when you don't ware it, it can fall apart)
  • Better socket for 9 volt battery (only if you are thinking of attaching the LED strips)
  • Using 2.8 instead of 2.4 (If you use 2.4 Adafruit touchscreen you are going to have hard time seeing things on your screen)

[Warning]

Do not charge and use it at the same time, because I found out that PowerBooster got extremely hot and it could potential damage your device.

Credit to: https://314reactor.com/2017/03/01/windows-98-wrist...

Special thanks to my professor: Jordan Kidney for helping me out with this project.