I've had several requests for an electric door lock or remote operated door lock so I decided to make a simple one using a cheap sliding bolt and an RC set-up using one servo.
You could just use the servo with a battery and a switch or button if you modify the servo by removing the circuit board inside. There are plenty of videos on YouTube showing how to do this.
RC transmitter and receiver
Probably a drill and screwdriver to mount the bolt on the door
I only used double sided tape for this demonstration.
In response to several requests I am giving the eBay listings used for my R/C equipment, but please understand I am not recommending these items to you for any special purpose. These are just the ones that I used. I would recommend you did your own search on eBay or Amazon or anywhere you like and make your own choice. In fact I would recommend you bought a simple 1 or 2 channel remote control relay unit designed for this sort of job which is much cheaper although you would need to modify the servo to make it work with DC voltage. Using a proper r/c transmitter is a waste of money for a door lock unless you intend to use it for planes or cars afterwards.
The radio control transmitter and receiver listing www.ebay.co.uk/itm/190888163364
Last time I bought servos I got 10 on this listing www.ebay.co.uk/itm/261521757538
and recently I bought a 12V Single Channel Fixed Encoding Wireless Remote Control Switch on this listing www.ebay.co.uk/itm/400628157682
The battery pack is 4 AAA batteries in a holder that came from a small torch that I modified by adding a suitable plug to match the receiver.
If you don't want to use an r/c servo then you could buy a 'door lock solenoid' actually designed for the job, here is an example www.ebay.co.uk/itm/190856003511
On the subject of modifying servos here is a very comprehensive video by Forrest Trenaman which is worth watching even though it leaves the servo controlled by a radio receiver so it is unsuitable for this case youtu.be/6G1nHfvl4aI
You could follow the general flow of this video but the simple change is that you remove the circuit board entirely and connect your DC power supply directly to the motor via your switch so the servo drives your door bolt in and out continuously and you have to judge when it is locked or unlocked.
Filmed using FujiFilm FinePix S4800
Edited using Serif MoviePlus Starter Edition
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