What Is Drift Exactly?
When a joystick develops “drift” it means that the controller is picking up inputs when you aren’t providing any. It’s a false reading that results in a character that keeps moving or a camera that just keeps spinning, even when your thumbs are off the sticks.
Nintendo’s Joy-Cons have become notorious for developing drift rapidly, but none of the current console makers offer controllers immune to drift. There have been reports of PlayStation 5 controllers having short lifespans before developing drift, and we’ve had a few Xbox controllers drift not long after buying them too!
Why Do Joysticks Develop Drift?
The analog sticks in these popular controllers use “potentiometers” to provide positional data to the video game’s computer.
Joystick potentiometers use Ohm’s law of electrical resistance as a way to measure position. Each potentiometer has a resistor in it, in the form of a curved track. Running on this track is a contact arm. As the contact arm moves up or down the track, the electrical resistance increases or decreases. The exact amount of resistance corresponds to a specific position on the track. Using two potentiometers to represent the two axes of the stick, you can determine the stick’s exact position with a high accuracy level.
Potentiometers are cheap devices that are effective for use in joysticks, but they have a major downside. The mechanism wears out as the contact arm moves up and down its track repeatedly. Eventually, the resistance level becomes unreliable as the resistor and contact arm wear on each other, which manifests as unwanted input.
How Does the Hall Effect Solve the Drift Issue?
The Hall Effect, named for Edwin Hall, is a measurable change in voltage caused by a magnetic field interfering with the flow of electricity in an electrical conductor. Hall Effect sensors in joysticks use permanent magnets and an electrical conductor that never physically touch. As the magnet moves relative to the conductor, the change in voltage is measured and translated into positional data.
Since there is no physical contact between these two components, the sensor should not wear out at the same rate compared to potentiometer sensors.
The Hall Effect Isn’t Perfect
To say that a Hall Effect sensor is immune to drift isn’t completely accurate. However, we’re talking about decades of use compared to as little as a few hundred hours for potentiometer sensors.
Besides this immaterial long-term wear and tear, Hall Effect sensors are sensitive to extreme cold and hot temperatures, but nothing that a human would tolerate or play video games in.
On the plus side, Hall Effet sensors aren’t susceptible to dust, dirt, moisture, or other similar issues that plague potentiometer sensors. Hall Effect sensors are the superior choice in all the ways that matter in the context of playing video games with a controller.
Why Aren’t All Controllers Using Hall Sensors?
There are already Hall Effect sensors in gaming devices you can buy today. You can buy upgrade kits for the Steam Deck that swaps in Hall Effect sensors.
The Ayaneo Air also comes with Hall Effect sensors, but it’s a rather premium device!
The truth is that Hall Effect sensors are only a few cents more expensive than existing controller sensors. Still, it’s only recently become practical to put them into the same space as current joystick sensors. We expect to see many upgrade kits for existing controllers and that major controller manufacturers will eventually switch to this technology. So keep an eye out for a Hall Effect version of your favorite controller, and kiss worries about controller drift goodbye for good.
