JSM Hammer

1
JSM Hammers

• CantTouchThis

Mid-Semester Demo
http//www.ece.cmu.edu/ece549/spring07/team8/
2
Re-cap Project Concept

• 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.

3
System Architecture
4
Status Update

• Accomplished
• Telos Motes can now send and receive messages to
  Java application
• Accelerometer can send readings to Telos mote
• Arm and disarm state accomplished
• Buzzer will sound when unauthorized motion
  detected
• Risk mitigated
• 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 mechanism 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

5
Parts and Pictures
Breadboard
Accelerometer
Buzzer
Rechargeable battery
Telos Mote
TI RFID reader
TI RFID cards
6
Demo Scenario

• Connection phase
• Arming
• Detect movement and sound alarm
• Disarm
• Detect movement and no alarm

7
Next Steps

• Have RFID reader to work with Telos mote (SW
  HW).
• Password setup and password screen pop-up.
• Integrate the components into a more compact
  device

8
Software Architecture
9
Lessons Learnt

• Sort out workspace properly and backup
  frequently.
• De-soldering can be pain.
• For accelerometer readings, we can use the
  Message Interface Generator (MIG) to generates a
  Java class representing a TOS message. This
  allows easier manipulation of the readings.
• Communicating to Telos mote through UART can be
  confusing format of message to send, or simply
  send single bytes, and initially it prints out in
  ASCII.
• When encountering an extended period of doubt,
  its time to look for TA(s).

10
Tentative Schedule
Week 7 Mid-Sem demo (stillCanTouchThis)
Week 8 Spring Break (notTouchingThis)
Week 9 Work on RFID and voltage regulator (startToTouchThisAgain)
Week 10 Settle all hardware issues
Week 11 Software (password configuration) Vigorous testing
Week 12 Tie up loose ends prevent trivial attacks on system (finishTouchingThis)
Week 13 Final Demo(REALLYcantTouchThis)
11
Q A