Transcript Bike Rack Availability Tracking System

Bike Rack Availability Tracking
System
Group 26: Sam Luo, Jason Pao, Jason Wang
Introduction
What is the project?
System that allows bike commuters to find a place to electronically park their bike
through an electronic bike lock that attaches to bike racks
Inspiration for the project:
Seeing cluttered bike racks outside of ECEB
Objective
Goals for this project include:
Find a way to display available bike racks through a common user interface
Creating a safe, easily activatable electronic bike lock that is available to anyone who owns a
RFID device
Solutions this project can accomplish:
Shortens the time bike commuters spend on identifying a safe location to park their bike
Decreases the cost of owning a bike by removing the need to buy a lock
Provides a safe lock for commuters to use due to the secure nature of U-locks
Physical Lock Design
Original Design: Block Diagram
Changes: Pressure Sensor
What was its purpose?
Detect whether or not a user properly inserted the U-portion of the lock
Why was it changed?
Swapped for contact switch
Exact amount of pressure exerted by the U-portion is irrelevant
Only needs to detect whether or not it is properly inserted
Changes: DC Motor + H-bridge
What was its purpose?
Keep the lock unlocked or locked
Why was it changed?
Swapped for servo motor
Horribly inefficient power consumption and fine tuning
Don’t need many rotations
Final Design: Block Diagram
Design: Microcontroller Software Flow Chart
Design: Microcontroller PWM Output
What was it required to do?
Maintain pulse width of 0.5ms for 90
degrees (locked) and 2.2ms for 180
degrees (unlocked)
Verification:
Output locked and unlock state, hold
oscilloscope parallel to PWM
output, verify pulse widths
Horizontal Cell Width: 2ms
Design: Contact Switch
What was it required to do?
Allow current to go through if
pressed
Verification:
Hook up the contact switch in series
with an LED, power source, and
resistor. LED must light up if
switch is pressed
Design: NFC Controller (PN532)
What was it required to do?
Identify a smartphone or RFID equivalent card if held within 1.5 inches of the
antenna
Consistently create a unique ID for each new RFID card read
Verification:
Hold two different RFID cards within 1.5 inches of the antenna. Unique ID for each
card should be consistent every time the cards are read
Design: Server Flow Chart
What was it required to do?
Proper I2C master functionality
Store data through a wifi connection
Verification:
Parse UID and send back verification
bit
Display and verify server data on
PHP server interface
Design: Smartphone UI
What was it required to do?
Query the server data relevant at the
time of the query request
Display the data properly after
queried data is retrieved
Verification:
Queried in 5 minute intervals, lock
status must update properly
Challenges: Power Circuit
What was it required to do?
Boost converter: output a step-up
voltage of 5V +/- 0.7V
Charging circuit: keep the
rechargeable battery above 2.5V
Verification:
Circuit had correct voltage mean but
too large of a voltage ripple
Dimensions: 3.2 x 1.65 x 0.8 inches
Conclusion
What was accomplished:
Available locks and lock status are viewable through an Android application
Electronic lock uniquely identifies RFID cards and smartphones
Electronic lock securely locks and unlocks
What didn’t work?
Voltage ripple was not controlled well due to poor boost converter design
Solar panel charging circuit failed to sustain voltage level
Future Work
What improvements can we make to this project?
Redesign the power system and components to be more efficient and sustainable
Move server to the cloud through IoT chips
Real-time update of info and map visualization of nearby racks
Create a catchy name
The acronym for Bike Rack Availability Tracking System (BRATS) isn’t very
attractive!
Credits
We would like to thank:
ECE 445 Staff
TA: Iain Brearton
Dave Switzer from the Machine Shop
Mark Smart from the Electronics Services Shop
Questions?