Can’tTouchThis

1
CantTouchThis
KSM Hammer
Jun Wei Chuah Shihong Ng Ming Yang Koh
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Project Concept/Motivation

• Concept
• This project will act as deterrence against
  laptop thefts, providing the owner a greater
  degree of security.
• The prototype integrates off-the-shelf embedded
  components, such as motion-sensing accelerometer,
  buzzer, RFID reader and tags for passive
  activation of the device and the Tmote Sensor.
• Motivation
• A laptop owner today is unable to leave his/her
  laptop unattended without risk of the laptop
  being stolen.
• Using our prototype system, an alarm will be
  activated if the laptop is being handled by
  unauthorized personnel.

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Competitive Analysis

• Caveo Anti-Theft PC Card
• http//caveo.com/products/anti-theft.htm
• The product works by sensing motion and emitting
  an alarm when its moved.
• Our product will automatically activate the lock
  when it does not sense the users presence

• Kensingstone Cable Lock
• http//us.kensington.com/html/11179.html
• The product works by physically locking the
  laptop to a secure object.
• Our product requires less user input and is a
  smaller and lighter solution.

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Requirements

• Functional Requirements
• Detects the presence of the user when in range
  and disarms the device.
• Arms the device when user is out of range.
• Allows software arming and disarming of device.
• Detects movement of laptop when armed and sounds
  alarm accordingly.
• Non-functional Requirements
• Reliability When armed, the device will detect
  significant movement and sound the alarm.
• Usability The device will require minimal user
  input after installation.
• Threshold Non-extended small movements will be
  tolerated by the system.
• Timing The alarm will trigger within 5 seconds
  of detection of motion.

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Technical Specifications
Microcontroller Moteiv Tmote Sky http//www.mot
eiv.com/products/tmotesky.php Buzzer Generic
Buzzer http//export.farnell.com/jsp/endecaSearc
h/partDetail.jsp?sku1192515 2.50 ea Motion
sensor Freescale MMA7260QT Accelerometer
http//www.freescale.com/files/sensors/doc/data_sh
eet/MMA7260QT.pdf 5.68 ea Rechargeable battery
Generic 3V Rechargeable Lithium
Battery http//www.action-electronics.com/batcomp
.htm Quote pending Wireless keycard components
RFID Reader Texas Instruments Series 2000
Micro Reader RI-STU-MRD1 http//www.ti.com/rfid/d
ocs/manuals/pdfSpecs/RI-STU-MRD1.pdf Quote
pending RFID Tag Texas Instruments Card
Transponder TRP-R4FF http//www.ti.com/rfid/docs/
manuals/pdfSpecs/TRP-R4FF.pdf Quote
pending Voltage step-up converter Texas
Instruments TPS61027 http//focus.ti.com/docs/pr
od/folders/print/tps61027.html 3.15 ea
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Architecture Block Diagram
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State Chart for Laptop
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State Chart for Microcontroller
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State chart for RFID reader
State chart for Buzzer
State chart for Accelerometer
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List of Use Cases

• TearDown

• Bootstrapping

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List of Use Cases (continued)

• User leaves laptop

• User moves laptop

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List of Use Cases (continued)

• User approaches laptop

• Thief moves laptop

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Risks

• R1. Compatibility between RFID reader and Telos
  Motes
• R2. Compatibility between voltage regulator, RFID
  reader and Telos Motes
• R3. Compatibility of rechargeable battery with
  rechargeable mechanisms on Telos Motes
• R4. Real-world performance of RFID reader with
  respect to range
• R5. Constraints with respect to the ports
  available on Telos Motes
• R6. Difficulty in finding suitable algorithms
  differentiating significant and non-significant
  movements
• R7. Usage under different laptop operating
  environments

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Mitigation of Risks

• Worst case usage of Zigbee protocol and Telos
  Motes for passive device
• (R1, R2, R4)
• Requires device to always be plugged into laptop
• (R3)
• Usage of 18-348 board to meet specific port
  requirements
• (R5)
• Usage of multiplexers to meet port requirements
• (R5)
• For worst case, any slight movement would trigger
  alarm
• (R6)
• Requires Windows as main Operating System
• (R7)