Sliding Greenhouse door opening and closing mechanism

thingiverse

This is a functional prototype setup. https://youtu.be/Uu6XQSz9-hE I adapted the frame so it fits snugly into my greenhouse door's slot, ensuring clearance when the door opens and closes. Two of these units are bolted side by side in that slot. To secure the bolt heads within the plastic casing, I used a screwdriver bit on an electric drill to rapidly rotate it, generating enough friction to melt the plastic and sink the head while preserving the teeth's integrity. Next, I modified the original pinion gear to fit onto the shaft of a 5rpm high-torque electric motor with a D-shaped pin. I'll connect this setup to an ESP8266 and a L298N H-bridge to remotely control the door based on temperature and humidity levels, as my greenhouse overheats even when the window is fully open. The reason for halving the gear ratio lies in incorporating a magnet hole. A hall effect sensor will detect disengagement of the teeth, serving as the standard parking position, allowing for door operation when not in use (the engaged teeth would lock the door). I'll also fit sensors to prevent excessive opening and closing. Warning: A safety feature is recommended - install an obstacle detection sensor in the door's path to prevent crushing injuries. In my setup, I anticipate that the teeth or motor shaft may jump or strip upon encountering an object, but this shouldn't be relied upon as a safety mechanism. A kill switch has been installed on mine for emergencies. Lastly, it's possible to leave the door closed with engaged teeth; if you're inside, you could be locked in! In such cases, the drive pinion gear can be slid off the shaft to allow door opening (no questions asked).