Goal: I don't want to open my door by inserting a key; instead, I want to unlock it remotely/wirelessly from the outside.

Pictures of my Mortise lockset:

http://i40.tinypic.com/5pftxi.jpg

http://i39.tinypic.com/11ghq9l.jpg

http://i41.tinypic.com/30kzsyc.jpg

Description: The first picture is a full shot of the interior knob. The second is a close up of the space between the lock buttons and the door frame (less than the thickness of a penny). The third is a shot of the lock buttons from the side. In this picture, there are two lock buttons: one for keeping the lock unlocked (bottom) and another to keep the lock always locked (top). Here, it's currently locked. Top one is depressed; bottom one is raised. They are connected, so if one goes up, the other goes down.

Notes: I have already considered electromagnet solenoids, replacing the locks, adding magnetic latches, and so on. I can't do anything to physically modify the current lockset and door.

Current design: My idea (so far) is to place magnetic copper wire into the top lock button. To hold it in place, I may use some sort of non-conductive clay with the radio-controlled power source taped to the interior door. What I'm hoping for is the magnetic copper wire will attract the metal lock button and raise it out of the unlock position.

Questions and concerns: I'm not sure how much copper I need, which direction the magnetic field will pull on the lock button, what type of remote-controlled power source would be most appropriate, how much power (or magnetic force) would be needed to pull the lock button, and what kind of clay or tape I should use to hold everything together without getting shocked and endangering my neighbors. I also don't know where to buy all of these items online. Could someone please guide me in completing this project?

Please critically analyze the faults of my project outline, answer all of my concerns (and add anything else necessary), and provide links to the materials you specify. I would really like to get this done as soon as possible.

Copper is non magnetic. Are you talking about making an electromagnet? With that mortise type lockset, you may not be able to develop enough power to rotate the knob.

I chose copper wire because (I think) it's thin enough to fit in the space around one of the lock buttons. Couldn't I produce a magnetic field by running a current through a coil of copper wire?

The electromagnets I've seen can't fit inside the crevice. It's less than four millimeters. However, is there an electromagnet available that I can stick to the interior door, position it parallel to the lock button, and then (on command) have it "pull" the lock button left and right? If so, could you please tell me where to buy it?

Take the knob off, fix a gear on it, mesh with a very low RPM controller, connect to a battery pack and use a radio control relay. Would be similar to a landing gear system for model airplanes. Try a good hobby shop.

I would like to take the knob off, but I can't. The whole thing is tightly glued to the door, and the institution that I'm staying at forbids disassembling the lockset. Do you have another suggestion?

The idea of placing an electromagnetic made of coils of wire in the depression around the top button is interesting, but I doubt there's enough space to get sufficient number of turns together with large enough wire gauge size to handle the current needed. Can you measure the force necessary to pull the top button out? Also, please confirm that the button is made of steel so is magnetic. As for placing a magnet device on the side of the door - i don't see how that could work. I think a more practical approach would be to build a mechanism that turns the inside door knob - I assume that if the door is locked turning the inside knob unlocks it, right?

Ebaines,

Yes, I'm worried that there's not enough space inside the depression for the wire. The force needed to push the bottom button in so that the top button pushes out is less than one pound. The buttons are indeed made of iron/steel.

Turning the interior knob with devices like these?

1. https://sites.google.com/site/teamto...id-door-opener

2. http://varenhor.st/2009/07/idoor-iph...ydraulic-door/

3. http://brettinman.com/blog/2010/01/0...#comment-10904

The first one seems simple enough, but I'm not good at coding. I'm also not good at setting up such devices. I'm not even sure which one will work best for me. And you are correct about the locking mechanism for the interior door knob. Turning it right will unlock the door. Would you be able to help me design a very, very simple device?

I like the second one (the hydraulic door opener at MIT), but you don't actually need the hydraulic stuff, just the mechanism that turns the door knob. A radio-controlled actuator with a mecahism that turns the knob like they've done would work. A contr9oller like this coupled to a 12V motor would be a god start: Amazon.com: Long Range 80 Amp RF Remote Control Reverse Polarity 12VDC Motor Control: Automotive