Original lock for door based on Arduino and capacitive sensor
Rob Hemsley from MIT made an original lock for the door based on the Arduino and the capacitive sensor.
This is the second version of the lock, the first version of the lock was developed based on RFID, its main disadvantage is the high cost of RFID equipment: about $ 80 needed to be spent on one lock.
The new version uses a capacitive sensor connected to a metal door handle. This solution is cheaper and more practical (you do not need to carry an RFID card, there is no RFID equipment that takes up additional space).
The device detects the touch of a person's hand on the door handle and monitors the intervals between hand touches the door handle. If the combination of touching the handle coincides with that stored in the EEPROM, the door will open.
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The existing door opening code can be changed quickly and simply: just touch the external door lock and after that “tapping” a new code on the handle.
The video shows the lock device in action, as well as the process of changing the opening code.
The door is opened using a servo that is attached to an internal lock. The capacitive sensor is attached to the metal door handle with an ordinary copper strip.
The capacitive sensor is sensitive to changes in the environment, which can lead to interference and false alarms. The device has a mechanism to counter this: an automatic calibration takes place every few minutes. Of course, this is not the ideal solution, but it works well and eliminates the need to carry around an RFID card with you everywhere.
For this device you will need:
The full source code of the project is available in the GitHub repository .
and drawings of servo mounting to the lock - here .
via
This is the second version of the lock, the first version of the lock was developed based on RFID, its main disadvantage is the high cost of RFID equipment: about $ 80 needed to be spent on one lock.
The new version uses a capacitive sensor connected to a metal door handle. This solution is cheaper and more practical (you do not need to carry an RFID card, there is no RFID equipment that takes up additional space).
The device detects the touch of a person's hand on the door handle and monitors the intervals between hand touches the door handle. If the combination of touching the handle coincides with that stored in the EEPROM, the door will open.
')
The existing door opening code can be changed quickly and simply: just touch the external door lock and after that “tapping” a new code on the handle.
The video shows the lock device in action, as well as the process of changing the opening code.
The door is opened using a servo that is attached to an internal lock. The capacitive sensor is attached to the metal door handle with an ordinary copper strip.
The capacitive sensor is sensitive to changes in the environment, which can lead to interference and false alarms. The device has a mechanism to counter this: an automatic calibration takes place every few minutes. Of course, this is not the ideal solution, but it works well and eliminates the need to carry around an RFID card with you everywhere.
For this device you will need:
- Arduino uno
- Servo
- Resistor (resistance 25 MΩ)
- Fiberboard sheet (for mounting servporivoda and lock)
- Several meters of wire
- Copper strip
The full source code of the project is available in the GitHub repository .
and drawings of servo mounting to the lock - here .
via
Source: https://habr.com/ru/post/149270/
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