Biometric fingerprint-based access control solution which can also be integrated with a vehicle ignition system was borne out of the need to proffer solution to challenges faced by apartment/house owners in handling their keys. These challenges can come in the form of loss, misplacement or theft. As an embedded systems designer, I conceptualized what ought to be the functionalities of this solution before I delved into the proper design of the schematic/printed circuit board (PCB) layout with electronic design automation (EDA).
Modules: ATMEGA328p Microcontroller, TFT_ILI9163C 1.4″ display screen, GT-511C3 biometric fingerprint Scanner, 5 volts single pole relay switch, 250kg Magnetic Iron bar, 12 volts 20000mAH standby battery, Rectifier circuit for charging of the battery.
ATMEGA328p microcontroller is a low power, 8-bit system on chip (SoC) reduced instructions set computer (RISK) system designed for embedded system technology. It has a parallel program and data memory to the central processing unit (CPU) thereby enabling it to achieve pipelining protocol, 32kb in-circuit serial program flash memory with reading and writing capabilities,1024B EEPROM, 2KB SRAM, 23 general purposes I/O lines, 32 general purpose working registers. etc
TFT_ILI9163C is an I2C 1.4″ colour display screen for status and other information.
GT-511C3 biometric fingerprint scanner is a 5 volts serial communication scanner with a capacity of 200 fingerprint templates. It can identify one to one (1:1) and one to many (1: N) with high accuracy matching. It has functions to enrol, Identify, Save and also delete. The delete function can be (ID: 1) or (ID: N).
5 volts single pole relay is for deactivating the magnetic Iron bar dock lock by switching between the normally closed and typical of the relay when a user presses a finger that matches fingerprint ID in the memory storage.
Magnetic Iron bar is a 250kg magnetic door lock which ensures that someone apartment is always closed whether there is grid power or not as the magnet can be powered with 12 volts standby battery power supply. The battery is for power supply in the event of power outage. 12 volts 1A rectifier circuit for charging of the battery.
This design after assembling with essential electronic components and ATMEGA 328p 16Mhz microcontroller programmed with Arduino sketch provided functionalities; like capturing of a user fingerprint by simply pressing an onboard push button that put the microcontroller in an enrolment mode.
This same solution can also be integrated into the ignition system of vehicles and customize it to an individual to guard against car snatcher/ theft. It will still be based on the same principle with a little modification between relay and ignition wire so that when a fingerprint is acquired and matched with already saved fingerprint template the relay as an actuator will start the engine.
This solution can be applied in other areas where forensic of an individual(s) are paramount since it has been scientifically proven that no two individuals have the same fingerprint.
You can visit www.henrismartech.wordpress.com for more on my projects.
By Henry Kenechukwu Nwatu
Email address: [email protected]