Looking to build a small enclosure for a robovac that can open/close a small light door (40cm x 15cm) via HA automation so the vaccuum can go out from his bat cave and do his thing.
In theory I would have a sonoff wifi switch that will control a linear actuator (like this https://www.amazon.co.uk/Justech-Actuator-Electric-Vehicles-Equipment/dp/B07S1N32FG/ref=sr_1_6?crid=3GJDJOCX62VK4&dchild=1&keywords=linear+actuator&qid=1596186528&sprefix=linear+actuator%2Caps%2C135&sr=8-6) for the opening/closing.
That does seem like a bit of overkill as I would need very little force to open this tiny door.
Does anyone have any better suggestions on how to open/close the door?
40 x 15. That is small.
You should be able to do that with a standard servo with a longer horn that pushes a stiff metal rod which then opens the door.
If you buy a servo with a reasonable torque - which rotates 180 degrees - and let us say a horn has its most far mounting hole 30 mm from the center then it moves a total of 60 mm from end to end.
If you let a stiff think rod push the door open 60 mm from the hinge (your door is 150 mm and I assume it is hinged on the long side then 60 mm is almost half way down. It should be a reasonable force that can open a thin door.
It is easy to control a servo from an ESP8266 and with a bit of simple code you can connect this to HA with MQTT.
I have a couple of servos that I control this way for rotating two cameras, and it was easy to make. Let me know if you need some sources.
I also have a small but heavy window which is bottom hinged which I pull open and push closed with a small micro linear actuator. I use a Actronix L12-50-210-6-P. It can push 50 mm. It runs on 5 V. It is controlled with a simple H-bridge and then I let the A/D on ESP8266 measure a voltage from the potentiometer of the actuator. And then again - connected to HA with MQTT.
You can see the linear actuator on my little Youtube video. It is only of the first sequences.
Warning. The A word is said many times.
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Ok so something like this might work, the door is plastic and quite light (kitchen plinth) https://www.youtube.com/watch?v=tlgLA-PT5eE
Yes the door is hinged on the long side at the top and it will open up, though I might need something that pushes/pulls a rob against the door. The one in that video only goes left/right