Electronic lock state detection systems and methods
An electronic key may include a partial capacitor comprising a capacitive metal plate in communication with a processor. The capacitive metal plate of the partial capacitor is configured to form a capacitor with a corresponding capacitive metal plate of a lock when brought into proximity with the metal plate of the lock. Data may be transferred from the key to the lock using a capacitor formed by combining the two metal plates, wherein a common ground is established between the metal plate of the key and the metal plate of the lock through a parasitic capacitance present between the key and lock circuitry. Audit trail data may be recorded based on usage of the key.
1. A method of detecting a lock state of an electronic lock, the method comprising:
by an electronic key comprising a hardware processor,
transmitting an unlock signal to an electronic lock that is mated to the electronic key;
receiving a confirmation signal indicating that the electronic lock is in an unlocked state;
storing a first time value corresponding to an unlock event time associated with the unlocking of the electronic lock;
transmitting a first heartbeat signal to the electronic lock;
receiving a response to the first heartbeat signal from the electronic lock;
determining based at least in part on the response to the first heartbeat signal that the electronic lock remains unlocked;
transmitting a second heartbeat signal to the electronic lock;
determining based at least in part on not receiving a response to the second heartbeat signal that the electronic lock is in a locked state; and
storing a second time value corresponding to a lock event time associated with the locking of the electronic lock.
2. The method of claim 1 , wherein said storing the first time value comprises storing the first time value at a memory of the electronic key.
3. The method of claim 1 , further comprising storing an indication of a length of time between the unlocking of the electronic lock and the locking of the electronic lock.
4. The method of claim 1 , wherein the second heartbeat signal is one of a plurality of second heartbeat signals.
5. The method of claim 4 , wherein the plurality of second heartbeat signals are transmitted to the electronic lock on a periodic basis.
6. The method of claim 4 , wherein a frequency with which the plurality of second heartbeat signals are transmitted to the electronic lock changes in response to not receiving a response to at least one heartbeat signal of the plurality of second heartbeat signals.
7. The method of claim 4 , wherein said determining that the electronic lock is in the locked state comprises determining that a response is not received to multiple sequential heartbeat signals from the plurality of second heartbeat signals.
8. The method of claim 1 , further comprising outputting the first time value and/or the second time value as audit trail data.
9. The method of claim 8 , wherein outputting the first time value and/or the second time value comprises transmitting the audit trail data directly or indirectly to an administrative system or an electronic lock management system.
10. The method of claim 1 , further comprising determining a location of the electronic key during the unlock event time associated with the unlocking of the electronic lock and storing the location of the electronic key in a memory that stores the first time value.
11. The method of claim 1 , wherein the confirmation signal is received from the electronic lock.
12. The method of claim 1 , wherein the confirmation signal is received in response to determining a relative position of the electronic key with respect to the electronic lock when the electronic key is mated with the electronic lock.
13. An electronic key comprising:
a memory configured to store computer-executable instructions; and
a hardware processor in communication with the memory and configured to execute the computer-executable instructions to at least:
transmit an unlock signal to an electronic lock that is mated to the electronic key;
receive a confirmation signal indicating that the electronic lock is in an unlocked state;
store a first time value corresponding to an unlock event time associated with the unlocking of the electronic lock;
transmit a first heartbeat signal to the electronic lock;
receive a response to the first heartbeat signal from the electronic lock;
determine based at least in part on the response to the first heartbeat signal that the electronic lock remains unlocked;
transmit a second heartbeat signal to the electronic lock;
determine based at least in part on not receiving a response to the second heartbeat signal that the electronic lock is in a locked state; and
store a second time value corresponding to a lock event time associated with the locking of the electronic lock.
14. The electronic key of claim 13 , wherein the hardware processor is further configured to execute the computer-executable instructions to at least:
store the first time value the memory of the electronic key; or
transmit the first time value to one or more of an administrative system, an electronic lock management system, a docking station, or a key retention device.
15. The electronic key of claim 13 , wherein the second heartbeat signal is one of a plurality of second heartbeat signals transmitted to the electronic lock with a particular frequency.
16. The electronic key of claim 15 , wherein the particular frequency with which the plurality of second heartbeat signals are transmitted to the electronic lock changes in response to not receiving a response to at least one heartbeat signal of the plurality of second heartbeat signals.
17. The electronic key of claim 15 , wherein the hardware processor is further configured to determine that the electronic lock is in the locked state by determining that a response is not received to multiple sequential heartbeat signals from the plurality of second heartbeat signals.
18. The electronic key of claim 13 , wherein the hardware processor is further configured to execute the computer-executable instructions to at least:
determine a location of the electronic key during the unlock event time associated with the unlocking of the electronic lock; and
store the location of the electronic key in the memory.
19. The electronic key of claim 13 , wherein the confirmation signal is received from the electronic lock.
20. The electronic key of claim 13 , wherein, when the electronic key is mated with the electronic lock, the confirmation signal is generated in response to a position of the electronic key with respect to the electronic lock satisfying a particular position associated with the unlocked state of the electronic lock.