Even Toothbrushes Run Doom These Days

The “smartification” of consumer products is getting out of control, y’all. It seems like it was only yesterday that we were all making fun of smart, internet-connected toasters and refrigerators. But those are practically antiques compared to the Evowera Planck Mini smart toothbrush. This toothbrush has a powerful microcontroller, WiFi and Bluetooth adapters, sensors, and even a color display to help people scrub their teeth more effectively. Aaron Christophel developed a method for hacking Planck Mini toothbrushes to load custom firmware. And it turns out that, yes: even toothbrushes run Doom these days.

Inside a Planck Min is a full-on ESP32-C3 microcontroller. It monitors sensors, like an IMU (Inertial Measurement Unit), to determine how well the user brushes their teeth. It can, for example, tell the user if they missed brushing a specific “zone” in their mouth. It shows the results on a 0.96” full-color TFT LCD screen, which can also show other information like the weather — because IoT. It is also capable of connecting wirelessly to an app and users can do ridiculous things with that, such as sending messages to friends’ toothbrushes. It’s all very silly, but we can see it being useful for parents that want to make sure their kids brush properly.

Our readers, however, know where this is going. After some experimentation, Christophel found that he could send over-the-air firmware updates to the Planck Mini’s ESP32 using his own ESP32 development board. That gave him the ability to load whatever code he wanted onto the toothbrush; he could display Rick Astley and read the data coming from the toothbrush’s sensors.

Naturally, Christophel decided to load Doom onto the toothbrush. That wasn’t even hard to do after he gained the access described in the last paragraph. Other hackers have already created Doom ports that run on ESP32 microcontrollers, so Christophel was able to load one of those onto the toothbrush as a firmware update.

That worked surprisingly well and the game is clearly visible on the toothbrush’s TFT LCD. To control gameplay, Christophel connected a Bluetooth mouse to the toothbrush’s ESP32. It seems a bit clunky, but forward-backward movement of the mouse maps to movement of Doom Guy (as opposed to looking up and down). That let Christophel play the game with just the mouse — no keyboard necessary.

We’ve covered many, many Doom projects over the years, but this one may take the cake. If you had told the developers at id software back in the early ‘90s that someone would run their game on a toothbrush, they wouldn’t have even been able to comprehend the idea.