Markus Opitz Builds "The Smallest DIY Joystick Remote Control in the World" with an Espressif ESP32

Maker and educator Markus Optiz has designed and built what he claims may be the smallest joystick-based remote control ever built — powered by an Espressif ESP32 microcontroller and communicating over the ESP-NOW protocol.

"The aim [of this project] is to make a remote control even smaller," Opitz explains of his latest creation, which builds on previous work building an already pretty-darn-dinky remote control. "And it works! According to my research, this is actually the smallest DIY joystick remote control in the world! It is useful for RC vehicles, robots, pan-tilt cameras, garage gates, and much more."

The tiny controller, roughly the size of the first joint of its creator's thumb, is, perhaps surprisingly, not built using a custom PCB or hand-wiring. Instead, its housing contains a Seeed Studio XIAO ESP32C6 microcontroller development board — though Opitz says other Espressif ESP32-based models, like the XIAO ESP32C5 or ESP32C3, will also work just fine. A compact five-way joystick is desoldered from its too-bulky breakout board and connected directly on top of the XIAO board — straddling its general-purpose input/output (GPIO) pins like a dead bug.

The remainder of the space in the custom case is taken up by a 100mAh lithium-polymer battery, linked to the XIAO ESP32C6 via a physical switch to cut the power when the remote isn't in use. Signals from the joystick — the four cardinal directions plus a "fire" button activated by pushing the joystick in — are transmitted to a receiver via Espressif's in-house 2.4GHz ESP-NOW protocol. "With antennas on the transmitter and receiver, I was able to achieve a distance of 300m [around 984 feet]," Opitz says. "Enough for an RC vehicle or a garage door."

The project is documented in full, including source code, on Instructables.