eHome

1. eHome Group 3 Matthew Beck Kyle Ferguson Travis Helms Dejan Lee-Hue

2. Goals To grant the user full control of their home via a Smartphone

3. Objectives • Household Power Monitoring • Outlet specific power monitoring and control • Light control • Keyless Door Entry

4. Specification • Power readings must be accurate to 2 kWh • Delay must be less than 5 seconds • Must accommodate at least 256 nodes (8 bit addresses)

5. Requirements • Power Readings must be accurate • Devices must be: • Self-contained • Small • Low Power • Safe • The user must be able to add/subtract devices easily • The user must always have control over their home • Entire system must be “plug and play”

6. Block Diagram

7. XBee Routing Protocol <’$’> <TTTTTTTT> <AAAAAAAA> <CCCCCCCC> • TTTTTTTTindicates device Type that is SENDING the message 00000000: hub 00000001: light 00000010: outlet 00000011: door lock 00000100 – 11111111: reserved for possible future use • AAAAAAAA indicates the Address of the End device (10 bits = 1024 possible devices) • CCCCCCCCindicates command requested (from hub) or responding to (from device) 00000000: CHECK_STATE 00000001: TOGGLE 00000010: SET_ON 00000011: SET_OFF 00000100: READ_CURRENT 00000101: READ_VOLTAGE 00000110: OPEN_DOOR 00000111 – 11111111: reserved for possible future use

8. Handshake

9. Whole House Power Monitoring • Monitor whole house power without messing with existing wiring • Use existing equipment: The residential power meter outside • Use a camera to record the meter and “read” it with software

10. Camera • Requirements • Weather Resistant • Built-in lights • Wireless streaming • Camera we chose: • Wansview NCB541W

11. Software • Image processing software • Will “read” the power meter to monitor power use • Will be hosted on our web server • Using C# • Built mostly from scratch • Simple imaging functions from existing library

12. Aforge.NET • An open-source imaging library • Provides basic imaging functions • Color, blurring and size filters, for resizing or grayscale conversion, etc • Provides Canny Edge Detector class

13. Classifying the Meter • 3 types of meters • “Clock-style” digit meter • Digital 7-segment digit meter • Analog rolling digit meter • Our system reads digital meters • Becoming more common • Easier to interpret – standard digit structure (7-segment rectangular digit)

14. Digit Locations • Multi-purpose • Setting digit locations for the first time will also provide the system with its first meter reading • Given by user on website • Website shows a frame from the camera • User clicks image to determine digit locations • Individual digit reading given immediately to help get it just right

15. “Read” the meter • Reading digits will be similar to finding them, using the same template key points. • Quicker, because digit locations are known, so only check there • Combine the individual digit readings to get the full meter reading

16. Storing Data • Reading history, along with account data and all of the calibration settings, will be saved in a SQL database • Database will be hosted on the same web server as the website and the software

17. Outlet Power Monitoring Overview • Device will plug directly into a home outlet • Web control granted • Obtain Power usage • Sent to web for user viewing

18. Outlet Power Monitoring Design • Voltage • Obtained directly • Wired to A/D pin • Run through peak detecting circuit

19. Outlet Power Monitoring Design • Voltage • Obtained directly • Wired to A/D pin • Run through peak detecting circuit • Over voltage protection via Zener (D1)

20. Outlet Power Monitoring Design • Current • Obtained using Indirect Current Sensor • Monitor gives time dependent AC output • Wrapped insulated live wire through sensor 4x for higher precision • Wired to A/D

21. Outlet Power Monitoring Design • Current Reading Software • Stores 200 readings at a time into an array • More than necessary to cover a 60 Hz time period • Low pass digital filter applied to array • Current value is averaged with 4 previous readings • Used for noise reduction • Maximum and minimum values are found in array • ((MAX – MIN) – TYP_NOISE) * GAIN_FACTOR

22. Outlet Control • Type C Relay used • SPDT • Normally closed track connected to 120V • Coil connected to ATMega controlled BJT

23. Light Control • Device will grant control of existing light • Push Button Switch • Digital Switch (via application)

24. Light Control Design • Digital Control • BJT grants user control of light

25. Light Control Design • Analog Control • 5V out connected to push button switch • State of switch monitored by I/O pin • Change of state = Change state of Input to BJT

26. Door Lock Challenges • Front door must always be accessible • Lost Phone • Power Outage • Front door lock must also accept key eHome

27. Door Lock Design • Electric Door Strike • 1.5A • 3-7V • Perfect for use with ATMega • MOSFET used to give logic level input • Handles 1.5A Safely

28. Door Lock Schematic

29. Website Overview • Objectives • Display current/projected bill • Display outlet power consumption • Toggle devices over internet • User login

30. Website Interface Structure • ASP.NET/C#, MSSQL • Abyss Web Server

31. Website User Account • Account Settings • Change password • Prompt for Cell phone number • Registration • Create username and password

32. Website Home Page Design • Current Bill/Projected Bill • Power Used to date • Log in/out • Video Feed

33. Website Device Page • Lists current connected devices • Can then monitor power (where enabled) and change state of device

34. Website Communication • Addressing • IP camera • Microcontroller/central hub • Xbee wireless communication

35. Website System Settings • Metertype • Price per watt rate

36. Work Distribution

37. Expenditures & Budget