Introduction: Pocket Pi - a Raspberry Pi Computer for Under $150

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About: I am a person who loves to create inventions and share them with the world!

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This is an affordable $100 raspberry pi computer. This computer is not the thinnest or prettiest thing on Instructables. This is for getting the job done. The shell is 3D printed. There is 1 charging port, for the motherboard. The keyboard has a wire designated for charging the keyboard and will not be noticeable on the outside. There are 3 USB 2.0 ports are for input. 1 will be used by your Bluetooth + wireless USB stick. Luckily, I have included a USB holder that holds your USB's. The screen is 4.3 inches and is not a touchscreen. You can easily make it touch screen compatible. The raspberry pi is a zero. This is because the Adafruit Kippah currently does not support the zero w. You will still need a wifi network! It runs NOOBS, but you can still download PC games on it. All you have to do is to search on google how to install PC games on NOOBS. You can use this to check up on things, play games, and use applications that are normally on PCs. It can do a lot of things that phones can do, but the computer is significantly cheaper. The parts are spread across 3 different websites. If you do not have a 3D printer or a soldering iron, you will have to but different parts. This will be explained in the steps. It should take you around 1 hour to build, but with shipping times and how long your 3D printer takes to print the parts, it could be longer.

Inspirations

https://www.instructables.com/id/Pocket-Sized-Linux-Computer-Pi-Micro/ , I tried to make it as similar as possible to this, but it didn't turn out quite as well.

Advantages

  • Interchangeable storage and software
  • Keyboard with all of the symbols + some extra ones
  • 2500mAh battery
  • Relatively Cheap compared to other ones.
  • Wfi+Bluetooth
  • The keyboard will never die
  • 3 USB ports
  • Has programs that you would find on laptops + desktops (ex. a version of Word)

Disadvantages

  • Very thick
  • 1 USB port used for wifi+bluetooth
  • No touchscreen
  • Everything is quite small on the screen
  • Only fits in big pockets
  • No Audio (unless you have USB audio)

Step 1: Get the Parts!

In order to make this you will need these parts:

40-pin FPC Extension Board + 200mm Cable: https://www.adafruit.com/product/2098 $4.50

Adafruit DPI TFT Kippah for Raspberry Pi: https://www.adafruit.com/product/2454 $13.95

Mini Bluetooth Keyboard: https://www.adafruit.com/product/3601 $12.95

Micro B USB 2-Way Y Splitter Cable: https://www.adafruit.com/product/3030 $2.95

Raspberry Pi Zero Budget Pack - Includes Pi Zero v1.3: https://www.adafruit.com/product/2817 $29.50

Battery: https://www.amazon.com/Attom-Tech-External-Emerge... $12.95

Wireless mouse: https://www.amazon.com/Foutou-Super-Optical-Wirel... $4.20

Display: https://www.aliexpress.com/item/CHIMEI-4-3-inch-4... $13.52

USB splitter: https://www.amazon.com/Onvian-Port-Speed-Splitter...$8.99

Bluetooth and Wifi dongle: https://www.adafruit.com/product/2649 $19.95

2 AAA batteries

Hot Glue Gun

Soldering Iron

Switch

Wire

To save you the math, the total cost is $124 + tax and shipping, so the total will vary. If you don't have a 3D printer, the total will increase. (If you already have some of these parts, you don't have to buy them. I already have the mouse and I already had a Bluetooth and wireless stick from a previous project, so for me, it was $100)

Step 2: Print the Parts!

You can download the USB holders here: https://www.thingiverse.com/thing:989003 (I did not make this, I take no credit)

If you don't have a 3D printer, you can order the parts at Shapeways: https://www.shapeways.com

The files I did create.

Attachments

Step 3: Getting the Parts for the Base

For this step you will need these parts:

Raspberry Pi Zero

Header Pins

SD card with NOOBS

Charging Cable

Kippah

USB OTG Host

Micro USB Splitter

Bluetooth Keyboard

40 pin extension cable

Mouse

USB Hub

Battery

Step 4: Solder the Header to the Pi

Solder the header directly to the Pi. Funnily enough, I had to do this twice, once for the pi zero w (Which I later found out doesn't work with the Kippah) and the pi zero.

Step 5: Attaching the Kippah and Inserting the SD Card

A long title, but an easy step. Insert the SD card and place the Kippah as shown in the picture.

Step 6: Inserting the Wires

This will get complicated later and you might want to label the wires. Connect the USB OTG Host into the micro USB port labeled "USB" THAT IS IMPORTANT. Then connect one of the ends of the Micro USB splitter into the other port labeled "PWR" ALSO IMPORTANT. I had to go back later for troubleshooting because my cables were not in the correct ports.

Step 7: Attaching the Ribbon Cable

This is a delicate procedure. On the extender move up one of the flaps. Insert the cable with the metal pins facing down. The blue should be facing up. Then take the other end and put it in the Kippah. The Kippah is different, instead of moving something up, gently pull the outer parts until the black plastic bar is completely out. Then, when you have put the ribbon cable back in, push in the black parts. The metal tabs should be facing up, NOT like the picture. (This will save you some troubleshooting time, as it took me 10 minutes to figure out what was wrong with my display.)

Step 8: Cracking Open the USB Hub

Take a small item and put it through the plastic case of the USB hub. Carefully remove the plastic parts and plug it into the USB port. Originally I didn't want to have to remove the cover, but it didn't fit in the casing, so I had to.

Step 9: Cramming It Into the Case and Soldering the Switch

Now, start to put the things in the case. Take out the SD card. The Kippah might be a little tilted, but that is okay. Solder the farthest 2 pins to 2 pins on the dpdt switch as shown in the image. You will be programming this switch at the end. You could also edit the casing so that there is no switch port and attach a tilt switch to turn it on. Do this before putting the Kippah. When I put the Kippah on, I had to strip of the plastic off the Micro USB to USB cable. If you do this, put a little hot glue on the side of the USB so nothing shorts. Now hot glue all of the parts. Make sure no hot glue gets into the ports! You can disassemble in order to put the parts in with more control. This is probably my 3rd or 4th version of this case.

Step 10: Coding the Software and the SD Card

You are going to download the pi bakery from http://www.pibakery.org/download.html . Put the SD card in the SD card adapter and launch the program. Make sure you have selected the SD card (mine was named recovery) and hit "prep for NOOBS". Once that is done, download the Raspian image here: http://www.pibakery.org/download.html . Do not select LITE. After around 10 minutes, it should be installed and go back into the program and hit "restore backup". Then choose the raspian-stretch img and wait for the program to finish. Once done, re-plug in the SD card, as it has been ejected. Then open "config.txt" and scroll down. Then, at the bottom, paste these lines of code:

# Disable spi and i2c, we need these pins.

dtparam=spi=off

dtparam=i2c_arm=off

# Set screen size and any overscan required

overscan_left=0

overscan_right=0

overscan_top=0

overscan_bottom=0

framebuffer_width=480

framebuffer_height=272

# enable the DPI display

enable_dpi_lcd=1

display_default_lcd=1

# set up the size to 480x272

dpi_group=2

dpi_mode=87

# set up the hsync/vsync/clock polarity and format

dpi_output_format=520197

# set up the size to 480x272

hdmi_timings=480 0 40 48 88 272 0 13 3 32 0 0 0 60 0 32000000 3

This is for the display in the link. Save the text file and eject the SD card. Plug the SD card back into the Pi. I looked this up on adafruit, where I got the parts, and I am saving you a lot of time by knowing that you can to this instead of setting the pi up on a external HDMI screen, etc.

Step 11: Attaching the Keyboard Holder and the Keyboard

Hot glue the keyboard with the holes facing down, as shown in the picture. The holes should be facing the back! (the back has no USB ports) IMPORTANT: Make sure your ribbon cable goes through the hole along with the charging cable for the keyboard. The backup battery cord needs to be plugged into the longer cable and stuffed inside the box. The battery should still be outside of the base. Then glue the keyboard on top. Your base is now finished! Mine is a little bent due to my impatience when putting it together. The Kippah is not all the way down in mine!

Step 12: Putting the Battery and the Screen in the Top Casing

Parts for the upcoming steps:

Screen

Sandpaper

Electrical tape

Colored Paper

Plug in the screen to the green 40-pin extender. Then, but the wise cable on the very bottom of the case. Place the battery on top of it, leaving the green circuit board and the yellow wire available. Then, bend back the ribbon cable onto the back of the screen and hot glue the screen on top of the battery. I wish I could say this step went without a problem but no, I had to create 3 versions of the screen.

Step 13: Putting on the Outline for the Screen and Hinges

Print the Pi outline and hot glue it to the screen. It might cover the screen by a millimeter, but that is ok. It won't affect how much is on the screen because there is a 2mm border from the edge of the display to what it actually shows. Put in the rods and place them on one side. Glue that one side to the hinge. On the other side, the rod shouldn't be poking through. This is good. Hot glue this end (just a little!) so it doesn't fall out. YAY! I had no problems with this step!

Step 14: Booting It Up!

Almost done! When you plug in your battery to the power cable, you should see a white screen, then a rainbow square. Wait until you see the desktop screen. If that happens, good job! You have successfully installed the software! If not, make sure your battery has been charged or go to the troubleshooting page.

Step 15: What You Get for $130

You get

  • Internet
  • File System
  • Terminal
  • BlueJ Java IDE
  • Geany Programmer's Editor
  • Greenfoot Java IDE(YAY)
  • Mathematica
  • Python 2&3 IDLE
  • Scratch 1&2
  • Sense HAT Emulator
  • Sonic Pi
  • Thonny Python IDE
  • Thonny (simple mode)
  • Wolfram
  • Libre Office- Base, Calc, Draw, Impress, Math, Writer (basically what you find on a windows computer)
  • Mail
  • MagPi
  • VNC Viewer
  • Minecraft Pi
  • Python Games (a lot of them)
  • Archiver
  • Calculator
  • Image Viewer
  • PDFviewer
  • SD Card Copier
  • Task Manager
  • Text Editor
  • Help
  • Preferences

Wow!

Step 16: Getting Wifi+Bluetooth and Coding the Power Switch

Plug in your dongle and boot up your system! Log into your wifi network and click the button on the keyboard for pairing. When it has booted up, open the terminal. Type this: curl https://pie.8bitjunkie.net/shutdown/setup-shutdown.sh --output setup-shutdown.sh , then hit enter. Then type this: sudo chmod +x setup-shutdown.sh , then hit enter. Finally, type in this: ./setup-shutdown.sh ,then hit enter. Go to the menus and hit "shutdown" to turn it off. Flip it twice to get back to the previous position and it should turn back on.

Step 17: Sanding and Glossing

Sand down any rough edges or exposed hot glue. I used a razor blade to take off the glue. Then, take your electrical tape and wrap it around the bottom.

Step 18: Enjoy!

You are all finished! Have fun! If something is not working, go to the troubleshooting page.

Step 19: Troubleshooting

Nothing happens

Make sure all of the connections in the base are correct and your screen is plugged into the extension and the ribbon cable plugged into the kippah. Also, make sure your SD card is plugged in.

Blank Screen

Make sure you have added that last bit of code to the end of config.txt and have plugged in your SD card.

The Switch doesn't work!

Make sure you have soldered the wires to the correct pins and have soldered them to the switch properly: One wire should be on one end, the other right next to it.

If you have more questions, put them in the comments section!

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