Never be locked outside your apartment again!

A smart system to warn the user when he's not carrying important objects when leaving the house

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The idea of the project consists in preventing the user from leaving the room forgetting important objects such as wallet, phone, keys and similar objects. Everyone can benefit of the system because it exploits low cost hardware and doesn’t require any direct interaction.

When the user is leaving the room, the system can detect if he’s not carrying some important object and warns him in multiple ways. It can also check presence of the objects when the user gets back in the room.

The system can warn the user on ad-hoc devices or on smart devices such as smartphone or smart watches.
For example it could show the items the user is forgetting on a display and emit a vocal warning (for instance "you are forgetting your smartphone !")
If the user registered a smartphone, it can get a warning on it (for instance "you are forgetting me !")


The only required setup consists in “tagging” important objects and teach the system to recognize them. Additionally, smart devices used to warn the user must be paired with the system.

For example, to teach the system to recognize the keys the user has just to tag the keys and show them to the interface.
The interface will ask the user what the object is and will start tracking it.

Information about tracked objects can be modified by the user on a dedicated web page, without having to deal with any complex electronic interface.


The system can work in environments of any size with no limit on doors number, but we will focus on a simpler system working on just one door because of restricted hardware and time resources.

It can track any kind of taggable object but we will work on easy-to-track important objects such as keys, wallets and smartphones.

Functional requirements

  • The system should be able to sense RFID tags placed on objects when the user is leaving the room.
  • The system should compare the carried objects with the objects saved on the database and check if some object is being leaved in the house.
  • If the user is forgetting some object the system must emit a warning on the device display (placed near the door) naming the object(s) the user is forgetting.
  • Additionally the system has a "do not allow door lock" signal wich can be integrated with external actuators to prevent the door from being locked in such cases.
  • After receiving the warning, the user must take the forgotten object or else tell the system that he wants to leave without the object, using the touch interface on the device (placed near the door) in order for the "do not allow door lock" signal to be released.
  • The user must be able to edit objects associated with him (remove or edit information) by mean of a web page so that each device equipped with a web browser can be used in order to do that.

Non-functional requirements

  • A warning can be emitted on paired smart devices such as a smartphone or a smartwatch, but in order to do this the user must download an app on the device.
  • Additionally, an internet connection is needed on the device to receive warnings.
  • Each device should then have a display with a touch screen, an RFID reader and an internet connection (either a WiFi or a cabled one).
  • RFID passive tags are used to tag objects so that they can be tracked by the RFID reader.
    RFID tags are available in many shapes to fit the objects they have to be placed on.
  • Since multiple devices should share information about user's objects and since the user must be able to edit information on associated objects on a web page, a web server is needed in order to sync objects data on multiple device and to serve web pages to the user when he wants to edit objects' information.
  • To identify the user on the web server a personal account is needed, so the user must create its own or use a default unique one, provided with the system.

The following diagram shows a sample architecture that can be used for this project.

Project Members

  • Tecu Artemis Adina
  • Fabio Fenoglio