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Productivity management with a twist — a rotary time tracker that uses magnets!

Arduino TeamAugust 14th, 2021

The recent explosion of the number of people working from home has led to some interesting problems, one of these being that getting distracted from your current task is easier than ever. To combat this issue, member quincy came up with an innovative solution that utilizes a small light-up disk to track what kind of work is being done and for how long, thus keeping the user accountable. 

Rather than creating a boring task-tracking cube or a simple timer, Quincy wanted something a bit more, in his words, “magical,” so of course this device would integrate magnets and blinking lights to achieve this goal. It consists of an upper disk with a central bearing that allows it to rotate freely between one of eight different options. The base meanwhile contains a central green LED and a set of three photoresistors. These components are combined in such a way that the channels within the underside of the upper disk form a sort of binary code for each task, so a position can be uniquely identified by seeing which photoresistors are currently active. There is a magnet under each task’s icon that lets it snap into place easily and prevents it from rotating further.

With the hardware completed, Quincy tested out his new rotary time tracker by having it output which task is currently being performed over serial, and then having a separate program take this data and display it in a nice graphical format. You can read more about this project and see the code/components used here on