Smart Portable Key ECE 445 Aashay Shah Akshay Chanana TA: Igor Fedorov Project No. 45 Spring 2013

Introduction Portable and secure key Multiple electromechanical locks Functionalities - Wireless communication between lock & key - Fingerprint Scanner to validate smart key - Controller validates encryption - Low power consumption and long system life

Block Diagram

Fingerprint Scanner Integrated Biometrics LEM-100 Module

LEM 100 Specifications Supply Voltage = 3.3 ± 0.5 VDC High Security Level Management of master and user: Registration, Verification, Deletion Template Capacity = 100

LEM 100 Application

Communication Protocol Controller to Scanner: Scanner to Controller:

Microcontroller TI MSP430G ± 0.5 V Low power consumption 1-2 kB Flash Serial Interface/UART

Key Controller Flowchart

Lock Controller Flowchart

XBee 1mW Trace Antenna - Series 1 50mA 250kbps Max data rate 1mW output 300ft (100m) range Built-in antenna RF Transceiver

CoolTerm Software Xbee Explorer USB LED Test Accuracy test (100%) Communication speed 9600 bps Range Test (26m)

Panel of Switches Multiple switches Integrated with Controller Signal sent to lock after validation Debouncing Circuit Pull down resistor at switch

Switch Circuit Pull down resistor Ensures input connected to ground To XBee Input

Debouncing Circuit

Debounced Circuit Simulation

Key Circuit

Lock Servo connected to deadbolt Position & rotation of servo controlled by Controller Unlocks when signal is received by XBee & verified by controller Locks when switch is pressed

Lock

Lock Circuit

Servo Position

Requirements and Verifications ModuleRequirementsVerificationPassed or Failed LockSuccessfully unlocks on receiving the key Sufficient power for servo to lock back Send a PWM signal via the controller for clockwise rotation to unlock Reverse PWM for anti- clockwise rotation using the 9V battery and regulators Passed Failed Rest of the modules SuccessfullyVerifiedPassed Less power received by servo Successful clockwise & anti-clockwise rotation using power supply Soldering issue

Power Considerations 9V battery used to power lock and key UA78M33 voltage regulator (3.3V - XBee, Controller and Fingerprint Scanner) -500 mA max current rating L7805 voltage regulator (5V – Servo and TTL chips) - 500mA max current rating

Calculations 25 oz-in/rotation= W/min Current Servo per revolution = 0.17 A Output Power = V*I = 9*0.17 = 1.53 W Time = 1.53/0.018 = 85 min Time per rotation = 2 sec Rotations = 85/(2/60) = 2550

Future Work PCB for lock and key Electromechanical locks Improve transmission range Multiple keys for users

Credits Professor Carney Igor Federov Mr. Wally Smith Mr. Skee Aldrich Mr. Dan March

Thank You! Questions?