This Unique Controller Features Single-Axis Joysticks

We often see video game controllers being used to operate robots and remote vehicles, and those controller designs are sensible when you consider the history of video games. The classic d-pad was a good choice for 2D game worlds and the dual-axis joystick was a natural alternative that happened to work well with 3D graphics when paired with a twin. But are those control schemes actually ideal for your use case? Maybe not, which is why you should take a look at Austin Allen’s DIY single-axis joystick controller design.

Allen didn’t design this for gaming — though it could certainly be adapted for that purpose. Instead, he created this to demonstrate the potential for single-axis joysticks. Compared to typical dual-axis joysticks, these may make more sense for your project. Imagine that, for example, you built a motorized camera slider. It only has a single motor and only moves along a rail in a single axis. In that case, a dual-axis joystick would be less suitable than a single-axis joystick. The superfluous movement in the second axis wouldn’t do anything and could make the joystick’s function ambiguous.

From a technical perspective, this is easy to understand. The joystick just moves on one axis instead of two. In theory, that makes the hardware simpler and cheaper. In practice, however, economies of scale mean that single-axis joysticks tend to a bit more expensive.

Allen’s controller design demonstrates the utility of single-axis joysticks with three different functions. The first adjusts an RGB LED’s color and brightness. One end of the axis is bright green and the opposite end is bright red. The second adjusts the position of a servo arm, with the joystick moving the arm either clockwise or counterclockwise from its center position. The third and final joystick is similar, but controls the rotation direction and speed of a stepper motor.

The only components in the 3D-printed controller enclosure are those single-axis joysticks. Their wires connect to an external Arduino Nano development board. There are fives wires: shared power, shared ground, and one signal wire for each joystick. These are just like potentiometers, so the Arduino only needs to perform an analog read on each signal wire to get the joysticks’ positions. The Arduino can then control the components accordingly. It can control the RGB LED and small hobby servo motor directly, but goes through a TMC2208 driver for the stepper motor.