Sounds like KISS principal is the best way to go. I definitely think the emergency external 9v battery terminals are required for peace of mind.
I think this is interesting, however, in all my years using electronic door locks, I’ve always been far too annoyed by the “low battery” delay and noise it makes to let it go too long… and well before the actual batteries die. I mean, the noise is annoying, but adding the delay before opening really drives the point home and I get the batteries changed pretty quick… within a week of that nonsense starting… I’ve never encountered a situation where the batteries have actually died on me… but that’s me… and adding external power pegs is easy enough… just make them small pegs so they both fit perfectly into the inside recesses of a 9v battery… don’t make them big lumps that are actually quite difficult to keep the battery terminals on while manipulating the lock (Samsung).
If it’s still needed I’ve got quite a lot of experience using CAD packages and CNC machining that could be put to use on the mechanical side of things. I’m also pretty good with electrics/electronics apart from the programming side of things.
Hows this as a start for the front and part of the internals?
First view is outside (plastic cover ~5mm gap for antenna and led?)
Second view is from inside looking at the securing plate for the external cover.
I’m thinking maybe this motor?
I love it. Personally I think it would be cool if the outer part was just a blank plate with the antenna behind it - not sure if that’s what you’re going for but looks good nevertheless
That’s exactly what I’m going for, I’ll try to finish the design today but there is still some details to be determined.
Like how far off the Centreline the cross for the lock is, how big the electronics are going to be etc before I can finalise it.
OK, so the mechanical side is pretty near done, I just need to know how big the electronics enclosure would need to be, antenna size and shape, which battery is planned on being used, and to mount the motor to the mechanism after some testing of the gearbox tomorrow.
I can add the emergency battery terminals at the front but it will make the front thicker, also does anyone know if there is a limit to how close the antenna can be to a metal surface and still function properly.
Here’s another couple images of the mechanism.
Just out of interest how many people would actually be interested in buying this lock or building it?
If the whole assembly is metal we probably won’t be able to read a glass tag implants. Try and read your implant using your phone with a piece of steel in the way. Aluminum would be a bit better, but it would still reduce the read range somewhat. Might need a plastic cover plate.
I thought the plan was to buy a premade lock mechanism and just stick some electronics in it?
Sorry should have explained better, the order of assembly on the exterior would be:
Steel | antenna | plastic | implant
I’m just concerned with the antenna so close to the steel, would it attenuate the signal at all?
Perhaps that is another way to go yes, I went down this road because if you’re modifying both sides of the lock it makes sense to me to just build one from scratch (with off the shelf bolt, thumbturn and motor).
Pretty sure we will build it.
The whole front plate should be metal with a plastic cover overtop. We will use ferrite polymer between the plate and the antenna coil. The coil itself will rest just outside the metal plate line… can explain more later when not mobile, but we can make this work… so it will go; Steel | polymer | antenna | plastic | implant
I’ve been exploring this plan for some time, and it might be possible to do with European cylinder locks, maybe, but deadbolt makers are just not happy to do that.
I definitely see this going in the right direction. If this is going to be used for outside doors, keep people who live with snow in mind. Cold temps tend to make these crap out fast. It saps the batteries.
… and I look forward to getting some when ready. You guys are making it easier every day.
Ill be first in line to purchase a few of these for my front/back/and side doors.
And will it have the capabilities to store several different tags? For instance, my wife doesn’t want an implant so she would a key fob to get access.
Or will there be a backup in case something fails? So you can still access your home?
I’m sure what you are asking is feasible, at this point I’d think that any tag that works on the 13.56MHz frequency would work.
ISO14443A & ISO15693
The whole idea is to not be tied into any specific fob.
As with the backup, I’m currently designing the battery pegs on the outside for the emergency battery.
How thick are people comfortable with the inside part of the lock being? is 50mm (~2 inches) too large?
I’d say 50mm is fine, the handle comes out further than 50mm.
Now saying that, being in Europe, I’ve never used a deadbolt on any of my doors so it might bother others. If you are housing the electronics on the secure side of the door, they wouldn’t necessarily need to be inline with the motor I would think.
Ok, here’s what I have.
Using the bolt that @amal found and this motor:
And a PP3 sized Lithium Thionyl Chloride battery (9V)
Ok first, zaaaang.
Second, why the 9v battery and not say, 4 AA user replaceable batteries with much more capacity? Is the goal to keep things small?
Also let’s get drawings… 3D and 2D for each mechanical part. We’ll need to run those through DFM and probably tweak things a bit. I do have a factory that is willing to look at the drawings and work with us on design manufacturing.