Mario Kart is THE party game to play when you have friends over and Mario Kart Wii is THE definitive Mario Kart Experience*. While I’ll concede that no one who plays competitively will ever use motion controls (and neither do I anymore), the intuitive skeuomorphic controls of the Wiimote makes the game accessible to even the most lives-under-a-rock non-gamers. That got me thinking, why aren’t there RC cars that use tilt to steer?

*I’ll also admit that the Wii version is incredibly unbalanced but the courses they introduced are absolutely iconic and beautiful. I’m talking Mushroom Gorge, Toad’s Factory, Coconut Mall (they’ve ruined the end part in MK8), Koopa Cape and one of the most this-is-the-track-made-of-rainbow-that-everyone-falls-off-of renditions of Rainbow Road.

The Build

After a bit of research, I found out that it was possible to connect a Wiimote to a Raspberry Pi and also came across an example script someone had written. This was way back in highschool, but I think it was this one by The Raspberry Pi Guy. It was very straightforward to modify his code to control the GPIO of the Pi.

In terms of electronics and hardware, I started by buying myself a cheap remote control car. After a lot of fruitless tinkering, I found it simplest to just completely bypass the existing circuitry and attach a H-Bridge to the motors directly.

At the time, I had an Arduino starter kit with a bunch of components that I never tried the tutorials for because I couldn’t immediately recognise what they were but I was happily surprised to have exactly what I needed for this project.

After figuring out how to control the motors, I also added wiring to control the LEDs in the headlights as well as a buzzer to use as a horn that I salvaged from something a long time ago. I made horn play La Cucaracha as a reference to Luis’ Van from Antman.

For power, I powered the motors using the original battery tray with AAs and a small phone power bank for the Pi. I couldn’t find an elegant way to put everything inside the car shell so I put the Pi and power bank onto the truck bed (a truck is a type of car). I did use a multi-pin female header (from some computer I assume) for the connection to the Pi to make it easy to pull out and use for something else (I only had the one Raspberry Pi Zero W at the time).

If I recall correctly the controls were:

Input	Output
Tilt	Steering
1	Reverse
2	Forwards
A	Headlights toggle
B	Horn

The controls match the ones in Mario Kart despite the car not handling like the game at all. The turn radius is much too wide. But it was a fun project.