ECE 110/120 Honors Lab Section : Electromagnetic Backpack Lock Taser

Alec Saebeler - aws2 - ECE 110

Diego Esquivel - diegoe2 - ECE120

Fred Chang--kehangc2- ECE 110

Introduction

Statement of Purpose

If there is one thing students could not live without, it would be the backpack. A convenient vessels for school work, textbooks, electronics, food (most important), and other miscellaneous yet necessary items. The problem most students and institutions face is theft of valuable items. We proposed a new type of lock, one that both secures the backpack and provides an passive system to notify the owner. Our design would incorporate a Hall effect sensor paired with an electromagnet. This sensor system would connect to an Arduino logic board which processes the signal and indicates whether to alarm or unlock.

Background Research

There are over 83 millions students, in the US alone, and 79 million of those wear backpacks. The reliance on backpacks by students is obviously tremendous. Unfortunately, theft is far more common than any other crime on college campuses. We want to lower the amount of thefts that occurs with students so we don't all lose our very expensive belonging.

Design Details

Block Diagram/Flow Chart

System Overview

Students use their backpacks constantly, so the system must have a small footprint. With this in mind, only the sensor and electromagnet will rest on/near the zipper mechanism. The remaining elements of the circuit will either reside on the outside of the backpack in a housing, or inside the backpack. The electromagnet acts as the input for the Hall effect sensor, which reads the magnetic field strength. Any foreign/non-approved change in the magnetic field will be registered by the sensor, and the signal passed on to the Arduino. The Arduino is the control element of the design. The signal will be handled by logic gates, with the Arduino overseeing and interpreting the inputs. After processing the information, the Arduino will sound an alarm if the magnetic field strength is too low, allow user input to break the system, or maintain its current state. The user can unlock the system through a designated input(whether it be voice, combination lock using XOR gates, or a numeric pad), which will prevent power from reaching the alarm part of the circuit, thus allowing the owner to open the backpack without triggering the alarm.

Parts

Arduino
Hall effect sensor
Logic Gates (AND,OR,NOR, etc)
LED(s)
Electromagnet (Small)
Numeric Pad, voice recognition shield, or combo lock
Resistors
Wires
Backpack
Buzzer/Alarm
Breadboard

Possible Challenges

Coding knowledge(or lack of)

Circuit wiring knowledge(or lack of)

Maintaining a compact size while not reducing effectiveness

Moving from stage to stage of our project

References

1.http://blog.al.com/living/2011/08/back-to-school_burden_79_milli.html

2.https://www.census.gov/prod/2013pubs/p20-571.pdf

3.http://www.pennlive.com/midstate/index.ssf/2009/08/campus_crime.html

Final Report

HonorsLabReport.pdf