1. SmartCup – Team 42 Harington Lee, Chirag Patil, Arjun Sharma 1

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3. Introduction  SmartCup  A module that attaches to the bottom of existing cups that tracks liquid levels and sends data to restaurant employees.  Simple design with built-in scalability  iOS application: Displays all cups and their beverage levels.  Hub: Performs error correction and Bluetooth transmission.  Attachment: Measures weight and cup motion. 3

4. Objectives  Motivations  Restaurant patrons want their drinks refilled and restaurants want to keep their customers happy (hopefully).  Better service = better reviews and higher tips.  Accuracy  Make sure data being sent is correct by detecting when the cup is not in motion.  Ease of Use  Wireless charging to keep enclosure closed.  iOS application for quick access. 4

5. Overall System Block Diagram 5

6. Attachment 6

7. Attachment Block Diagram 7

8. Attachment PCB 8

9. Wireless Charging Coils 9

10. Cockcroft Walton Generator  Voltage Multiplier and AC to DC converter  Ladder network of capacitors and Schottky diodes 10

11. Battery Charging  MAX1555 Battery IC  Controls charging of the battery from the output of the Cockcroft Walton Generator  Output goes to 3.3V voltage regulator  Powers weight sensor, accelerometer, amplifier, and transceiver 11

12. Weight Sensor  3kg load cell  1.2 mV/V Output  Instrumental Amplifier (INA122UA)  With R G = 47  Voltage ranged from 1V to 3V 12

13. Accelerometer  ADXL335  3 axis detection  Starting voltage reading ± 0.07 V as threshold  Mapping voltage to microcontroller  analogRead() maps input voltages of 0 – 3.3V to 0 – 1023 13

14. Attachment Microcontroller Logic  Initial weight and accelerometer values recorded at start  Pulsing transmitter on and off  Interfered with instrumental amplifier voltage readings  Data formatted into packet and Checksum is generated  Thresholds for empty and full set in the app 14

15. Flowchart 15

16.  90/10 split between receiving and transmitting Attachment Battery Life Task Current ( Receiving)Current ( Transmitting) Total25mA29mA 16

17. RF Transceiver  Need to communicate data between the attachment and the hub.  RF communication is preferred.  Long distance  Multiple devices  Texas Instruments CC1000 RF transceiver  Programmable to 315/433/868/915 MHZ  Adaptable for ideal power reception at 3.0-3.7V  External impedance matching network. 17

18. How to Transmit RF Data? AttachmentHub 433 ±10 MHz Encoded data, known clock speed, known baud rate 433 ± ??? MHz Unknown data, possible clock drift, unknown baud rate?? TransmitterReceiver 18

19. Packet Transmission Protocol PreambleCIByte 1Byte 2Byte 3 EOM Data Packet (35 bytes) 19

20. Clock Data Recovery **Keysight, Electrical and Optical Clock Data Recovery Solutions 20

21. Impedance Matching Network 88-j26 Ω 50 Ω 21

22. LC Network Simulation 22

23. Transmitter Antenna Response -29.96 dBM at 1.5 feet 23

24. Transmitter Antenna Response -36.70 dBm at 30 feet 24

25. Receiver Harmonic Response 25

26. Attachment PCB Schematic 26

27. Attachment PCB Layout 27

28. Hub  Performs error correction on incoming RF packet.  Transmits data via Bluetooth. 28

29. Hub Block Diagram 29

30. Hub Microcontroller Code  Primarily does ECC and packet conversion between async systems.  Maintain message FIFO from attachment. PreambleCIByte 1Byte 2Byte 3 EOM PreambleUUID Header Advert. Channel Payload Access ID Prefix EOM RF packet Bluetooth packet 30

31. Bluetooth Module  HM-10 Bluetooth 4.0 module  4-wire SPI interface  Switched to serial due to solder issues 31

32. Hub PCB Schematic 32

33. Hub PCB Layout 33

34. Software 34

35. iOS CoreBluetooth  iOS7 has a provided CoreBluetooth SDK  Peripheral: Bluetooth Hub (uses UUID to connect)  Central: Phone 35

36. Peripheral Broadcasting  Important to understand layout of the broadcasted data  CBService: Weight Info  Characteristic 1: Cup ID  Characteristic 2: Cup Weight 36

37. Multiple Weight Values  Each Cup has to have its own view controller 37

38. User Interface Decisions  Green  100%-51%  Yellow  50%-26%  Red  25%-0% 38

39. System Integration  Completely Integrated  Weight Sensor  Microcontroller code  Bluetooth/RF  iOS App  Partially Integrated  Accelerometer 39

40. Future Work  Multiple Attachments  (2400 bits/sec)(1byte/8bits)(1device/35bytes)(10sec) = 85 attachments  BLE range  Use Android Instead  Minimize physical footprint  3D Print/Moldable Plastic Attachment  Cup/Table layout 40