1. Safety Motion Detector Final Presentation Senior Design I December 1, 2011

2. Safety Motion Detector Team Alden Stennis Jason Smith Programming Sensors Geoff Jakins PCB Design Website PCB Design Sensors Dr. Donohoe Faculty Advisor Electrical Engineer Programming Sensors Electrical Engineer Justin Parker Electrical Engineer

3. Outline Problem Solution System Overview Constraints Technical Practical Evaluation Senior Design II References

4. Problem and Solution

5. Problem Utility workers alone are in the field getting injured and are unable to receive help within a reasonable amount of time. There are approximately 600 deaths yearly from falling accidents in the work field.

6. Solution Safety Motion Detector – Wrist device monitors user’s movement – Signals the base station when no movement is detected

7. System Overview (Wrist Device) Motion Sensor Power Supply Transceiver MicrocontrollerInterface

8. Technical and Practical Constraints

9. Technical Constraints ConstraintDescription NotificationsVisual displays must indicate the safety status based on the user’s movement. Transmission DistanceThe base station must communicate data with the detection unit up to 200 feet. Battery LifeThe batteries must last for at least 24 hours. Temperature RangeThe SMD must withstand temperatures in the range of -40° to 185° F. Motion Detector Sensitivity Minimal motion, acceleration between -1.5 and +1.5 g 0 with minimum increments of 0.1 g 0. must be detected along one or more axes.

10. Practical Constraints TypeNameDescription ManufacturabilitySize The dimensions must be no larger than 3” wide, 3”long and 1.5” high SustainabilityRuggedness The wearable device must be capable of withstanding everyday use in the field.

11. Manufacturability Device must be small in size – Device will be no larger than 3” wide, 3” long, and 1.5” high – Must be wrist wearable to increase efficiency – Must not interfere with the user’s work

12. Sustainability Must withstand everyday use in the field – Water resistant – Function properly in hot or cold weather conditions Device encasement durability – Strong enough to handle accidental impact

13. Evaluation

14. Wrist Device

15. Microcontroller

16. Wrist Device Accelerometer

17. Wrist Device Notifications

18. Wrist Device Transceiver

19. Base Station

20. Transceiver

21. Base Station Microcontroller

22. Base Station Notifications

23. Acceleration Wrist Device: Standstill While the wrist device is at a standstill, the voltage output of each axis remains constant. The voltage of the z-axis is higher because of gravity pushing down on the top of the accelerometer.

24. Acceleration Wrist Device: Free Fall The highlighted values represent the wrist device in freefall. The Z-axis voltages were graphically plotted to show constant acceleration.

25. Range Testing A range test was done by separating the wrist device from the base station in 50 ft increments to check for proper functionality. Once the constraint of 200 ft was met, additional tests were done in increments of 10 ft to measure the maximum range.

26. Out of Range Test If the user is out of range, the notification lights will blink repeatedly. This will continue until the devices are back in range to communicate with each other.

27. Battery Life Current Draw - Microcontroller Awake Current: 1.173 mASleep Current: 0.034 mA

28. Battery Life Current Draw - Transceiver Awake Current: 49.447 mASleep Current: 0.033 mA

29. Battery Life Current Draw – Accelerometer Sleep and Awake Current: 0.268 mA

30. Battery Life Current Draw – Total Circuit Awake Current: 64.327 mASleep Current: 5.365 mA

31. Actual Battery Life DeviceAwake Current (mA)Sleep Current (mA) Microcontroller 1.1730.034 Accelerometer 0.268N/A Transceiver49.4470.033 Total64.3275.365 Time Asleep(s) Time Awake(s) Sleep/Wake Cycle(s) Average Current(mA) Battery Life(hours) Battery Life(days) 060 64.33046.631.94 8.51.51014.205211.198.80

32. Senior Design II Goals

33. Improve Battery Life PCB Design Build Enclosure and Package Improve Software Test Final Design

34. Timeline for Senior Design I AugustSeptemberOctoberNovember Research Ordering Parts Design Programming And Construction Prototype

35. Timeline for Senior Design II JanuaryFebruaryMarchApril PCB Design Software Refinement PCB Populating Testing Enclosure

36. References [1] "Census of Fatal Occupational Injuries (CFOI) - Current and Revised Data." U.S. Bureau of Labor Statistics. Web. 07 Sept. 2011..http://www.bls.gov/iif/oshcfoi1.htm [2] “Pic24FJ64GA102” http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en536117 [3] ”Pic24HJ32GP202” http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en530328 [4] ”AD22285-R2” http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=AD22285-R2TR-ND [5] “MMA7660FCT” http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=MMA7660FCT+ [6] “ADXL335” http://www.sparkfun.com/products/9269 [7] “How does ZigBee compare with other wireless standards?” http://www.stg.com/wireless/ZigBee_comp.html [8] “Xbee, Xbee Pro, Xbee Pro XSC” Page 5 http://www.sparkfun.com/datasheets/Wireless/Zigbee/XBee-Datasheet.pdf

37. Safety Motion Detector Final Presentation Senior Design I December 1, 2011