ECE 110/120 Honors Lab Section : RFID Door Lock

Statement of Purpose

Our goal is to create an RFID door lock, or an electronic lock that can only be opened by a key with the specific radio frequency as the lock. We hope to build this secure lock because it is a contactless and convenient type of technology that can reduce the spread of COVID (no contact) and the chance of unauthorized entry to a person's home.

Background Research

We have started to research the different systems in our project, paying particular attention to the areas of RF and microcontroller programming. In the area of RF engineering, we are researching antenna design and general RF design procedures to preserve signal integrity. We are also looking into how we can make the RF part of our project smaller. This seems to be the limiting factor in how we can actually mount the lock in the door. For the microcontroller we have found the using NodeMCU, which has a Wifi Antenna, to be the most effective. This will ensure that we can make the device IoT enabled. Luckily, this microcontroller is very similar to an Arduino and uses the Arduino IDE - a primary reason for why we are using it. Finally, to come up with the idea for this project, we drew inspiration from retail IoT and home security devices. Our device is different in that we want it to fit on the inside facing part of the door, rather than outside the door. There also are not many (if any) IoT NFC/RFID security devices for residential use, although many hotels use this technology.

In regards to the lock itself, the point of this lock is so it is in theory completely inward facing and changing the lock will not be required. In theory it should be able to turn any deadbolt in which the lock turns a standard 90 degrees. The mechanical component of this will be done using gears. and a stepper motor to turn the deadbolt and we will attach the deadbolt to the door by using strong but removable when needed adhesive. This solution has been done on some Smart Locks already such as the Sesame smart lock. (https://candyhouse.co/) Because of how RFID works it can go through wood and most other materials except metal. As long as the user does not have a metal door it should work through the door, with moderate range. I have tested this theory using a HID RFID reader that I own, as long as we make a proper coil we should be able to achieve this.

Block Diagram / Flow Chart

System Overview

Parts

Possible Challenges

We are struggling with how to power our RFID door lock. If we use batteries, they would be inefficient and would not last long. If we use a cable connected to the wall, it would be bulky and not user friendly. We also do not know if the coils in the motor or the WiFi module will interfere with the RFID network, so we might need to build shielding.

References

"What Is The RFID Lock? - Make Locks". Makelocks.Com, 2021, https://www.makelocks.com/news/what-is-the-rfid-lock.html#:~:text=An%20RFID%20lock%2C%20also%20called,physical%20contact%20with%20a%20reader. Accessed 18 Feb 2021.