Building a Wireless Charger That Never Misses

Wireless smartphone charging is great in theory, but much less so in practice. Personally, I abandoned it altogether, because half of the time my alignment would be slightly off and I’d wake up with 10% battery on my phone. It is easier to just plug in an old-fashioned and reliable cable. But HTX Studio didn’t want to give up on wireless charging, so they built this desk that always achieves perfect alignment.

The basic idea here is to move the wireless charger to the phone, no matter where the user places the phone on the desk. Alignment isn’t a problem and the user can set the phone down wherever is the most convenient.

To pull that off, HTX Studio had to build a motion system to physically move the wireless charger around underneath the desk’s top. That is a two-axis motion system, similar to what you’d find on a pen plotter. Stepper motors turn lead screws, providing actuation on each axis to move the wireless charger to any XY coordinate. Stepper drivers send power to those motors and they operate under the control of an Arduino board.

But how does the desk know where the phone is? HTX Studio used an overhead camera to detect the position of the phone — though they don’t provide information on how it does so. Presumably, it is some kind of computer vision or object recognition model.

There are also several extras, including some kind of screen to display graphics, the ability to move between different things that need charging (like an iPhone and then AirPods), a built-in Mac Mini, and motorized desk height adjustment. Unfortunately, HTX Studio didn’t give any technical details about any of that, so I can’t tell you how it works.

However, I can tell you that this desk is very cool and I wish I had it. It would probably be enough for me to embrace wireless charging.