The model of sliding doors is built from the Lego Wedo 2.0 educational kit. A combination of mechanical gears is used to operate the sliding doors. Namely, these are auxiliary belt and bevel transmissions, and the main one is rack and pinion. When an object enters the range of the distance sensor, the doors slide open, and after a few seconds they close back.
The set includes step-by-step building instructions and an example of program (in Lego Wedo 2.0 environment).