physical + electronic lock

[vinnie]

I was thinking for a high security locking mechanism if one were to have all the pins insulated from each other and and upon contacting all pins at once a circuit would be completed allowing for an electromagnet to release another pin. So say there are 5 pins, then a 6th pin is behind them and inaccessible. this 6th pin is held up by a small electromagnet, so when the electromagnet is on this pin is blocking the shear line. If the electromagnet is turned off, the pin falls and the lock can be opened. To switch the electromagnet off, one would have to connect all the other 5 pins at once and turn the lock. This would make it nearly impossible for anything but actually using the key. For security measures the default position of the extra pin is open in the case of a power outage, in which case it would act as a normal lock. The alternative being the it defaults locked, so if someone cuts the power it will be permanently closed.

Does this seem like much more trouble than it's worth? As I could think it might be useful in high security situations like banks where they always always have backup power making these locks at all times practically unpickable

[MacGyver101]

It's a good principle: what you're trying to do, in essence, is you're trying to ensure that you're testing all the pins at once (to prevent someone from manipulating the pins one at a time). Abloy does a good job of this with their Protec system, for example, where the discs are all locked into position before the sidebar tries to move into position.

The main downside I can see is that filling the lock with anything conductive (water, conductive gel, etc.) would defeat the mechanism without interfering with picking.

If you wanted to extend the idea, you could use serrated bottom pins, and a have a second mechanism inside the plug that pushes a "sidebar" into the bottom pins (locking them in place) at the same time that your 6th "check pin" is released. (As a random thought.) I think physically locking the bottom pins in place somehow -- before you release the plug to "test" them against the shear line -- is the important part.

[vinnie]

hmmm, yea I suppose you're right about using a fluid conductor to get by this. as for having serrated pins with a sidebar to lock them in place once 6th pin is in place, one could potentially get by that by just picking the lock first and holding tension with the pins at the right level then applying conductive fluid of some sort.

all in all, I'm thinking to make this a more successful locking mechanism it would require many more intricacies than one really wants to build into a lock. I'm of the idea that simple is better.

[vinnie]

although you did get me thinking about a few other possibilities. thanks! I'll post back in a few days when I have time to draw out an idea I've got on my mind now.

[Squelchtone]

You could make the entire keyblade and the plug electrically Grounded, and make the key pins be insulated all the way around, except the tips that touch the key Positive, then for the key bitting, make it so the key is made of GM VATS resistors (1990's technology used by General Motors automobile manufacturer, where a resistor pellet was pressed into the blade of each key and the car ingition would turn but not start if the resistor value did not match what the vehicle computer was expecting to see) of different values and heights that are "plugged" into the blade of the key, like a make up key, then the lock tests the resistance of each "key cut" as well as the height of the resistor pellet to see if there is a mechanical shearline. If resistance of each one matches within the tolerances, a solenoid or worm gear drive is activated and allows the plug to turn.

example GM VATS key:


chart of the key blanks and their possible resistance ranges in Ohms:


Now just imagine if every key cut was a different resistance, not just the blade of the key.
Squelchtone

[Altashot]

I can just imagine how many problem one could have if these locks were ever used.
In the case of GM VATS for example, sometimes on very hot, sweaty days, VATS keys quit working if they were kept in one's pocket.
they get too hot which increases the electrical resistance. The computer reads it as a higher ohm. Once cooled, they work again.
As for the electromagnet idea, they often suffer from residual magnetism and wont release right away. It would be a bit like a gummed up pin that wont drop.

My $0.02

M.