PiChuk, a wireless Raspberry Pi joystick controller.

This is my attempt to stick a Pi Zero inside of a Wii Nunchuk. I use this to control an organization-type program I made, but I can see this being useful for videogames as well.

It is powered by a 750mAH LiPo battery used for drones. I used an Adafruit Powerboost to regulate the power. It uses the Wii Nunchuk's joystick PCB, buttons, and top cover.

I tried to get this as compact as possible, but there wasn't nearly enough room to actually fit a Pi Zero completely in a Wii Nunchuk, not even considering the other parts. I modelled the lower body of the Nunchuk to fit all the components in the hand-grip part. I planned to make a cover for the grip portion, but it feels ok to hold already, and I didn't want to add extra bulk.

I use this with my Vufine wearable display, which is why I needed it to have a standard HDMI port.

Thankfully, the Nunchuk's PCB has a built-in analogue-digital converter, so I didn't have to use a separate one.

Components:

• Wii Nunchuk
• Adafruit Powerboost 1000C
• 750mAH 3.7V Holy Stone Model 752555
• HDMI ribbon cable assembly:
  • Female standard HDMI
  • Male mini HDMI
  • 10cm ribbon cable

To get the Pi to recognize the joystick's signal, I used this module.To use the Nunchuk's hardware to control the cursor, I used the Python module Pynput.

This is the script I made to control the mouse and click buttons:

from nunchuck import nunchuck
import time
from pynput.mouse import Button, Controller
wii = nunchuck()
mouse = Controller()


while True:

    x = wii.joystick_x()
    y = wii.joystick_y()
    x_scaled  = ((x - 130)*2)/260
    y_scaled = ((y-135)*2)/270
    x_curve = int((x_scaled * abs(x_scaled))*100)
    y_curve = int((y_scaled * abs(y_scaled))*100)

    time.sleep(0.02)
    mouse.move(x_curve, y_curve)

    if wii.Button_z() = True:
        mouse.click(left,1)

    if wii.Button_c() = True:
        mouse.click(right,1)
'''
You might have to tweak the values for x_curve and y_curve because each Wii joystick potentiometer I've tried had different limits.
It's just rise over run, where 2(x-130) is Δx and 260 is Δy, so if your cursor moves in the opposite direction after moving the joystick all the way,
you need to lower the value of that direction. 
'''