Justin Simmons
Mike Stein
Bryan Edelman
Alex Fosdick
SPACE WOLVERINES
CAPSTONE SPRING 2010
MISSION STATEMENT

Design and implement an automated beverage
dispensing system
 System
eliminates the need for human servers
 On demand beverage dispensing for users
WHY?


Crowded/Long Lines
Customer
Satisfaction


Money
Theft

Regulated
Volume
SYSTEM OVERVIEW


Beverage dispenser will monitor and control its environment
Owners can




Users will




control and limit access
monitor system status
track customer trends
be registered
have their beverage purchases tracked
be billed automatically
Two operator interfaces


PC with GUI
Handheld unit with touch screen LCD
CASE STUDY- 5 GUYS BURGERS AND
FRIES
Beverage Dispensing Unit
(BDU)
Wireless Control Unit (WCU)
Computer Module (CM)
1 CM
Longmont
(Medium Volume)
1 CM
Fort Collins
(High
volume)
Master
Database
1 CM
Aurora
(Low volume)
BEVERAGE DISPENSING SYSTEM (BDS)
Beverage Dispensing Unit (BDU)
•System Data Acquisition:
•Temperature, Pressure, Volume
•System Regulation
•User Interface
•Database Access
Computer Module (CM)
Wireless Control Unit (WCU)
•Displays Current State
•Control System
•Home Database
•Statistics Regarding Usage
•Graphical User Interface
•Displays Current State
•Control System
•User Interface
•Database Access
PHYSICAL SYSTEM FOR DISPENSING UNIT







Used Refrigerator
Refillable Sankey Keg Shell
CO2 Tank
Dual Gauge - Adjustable
Pressure Regulator
Keg Tap
Misc. Hosing and O-rings
Spout
FLOW DIAGRAM (BDU)
BDU
dispenses
liquid
UI Shows
Approval
Yes
System
Monitors
State
(Idle)
User
Places
Cup
User
Swipes
Card
BDU
Signals
Host PC
Is User in
Database?
No
UI
Shows
Error
DISPENSING UNIT
3-Track Card
Reader
BEVERAGE DISPENSING UNIT (BDU)

Custom PCB


Microcontroller
Wireless Transceivers





Magnetic Card Reader (3-track reader)
Interactive (Graphic LCD/LED’s)
External Data Memory (Flash)
Database Accesses


Nordic/ZigBEE
Prompts Database for User Authenticity (MySQL)
Servos/Motors for Controlling System State (TBD)


Starting/Stopping Flow
Drink Tilt (Motor controlled/Counterbalance)
BDU CONTINUED

Temperature

Analog Devices Temp Sensor
± 0.50C accuracy, 16-bit I2C or SPI
 0.06250C resolution


Digital Potentiometer used for control temp
 I2C

Pressure Detection

Multiple CO2 pressure transducers


or SPI
0 – 30 psi and 0 – 1800 psi
Volume Detection


Flow meter (SwissFlow Meter)
Force sensor

FlexiForce Sensor 0-100 lb. range
FLOW SENSOR
Track the flow for each beverage pour
 Calculate the remaining volume of the system
 SwissFlow Sensor Type 800


Designed to measure liquid flows for a large variety of
liquids
Flow is measured by a turbine in the flow path
 Infrared beam is used to detect rotation of
turbine
 High sensitivity: ± 6000 pulses/liter

SOFTWARE AND FIRMWARE (BDU)

Wireless Communication


3-Track Magnetic Card Reader




Get_Temp( ), Get_Pressure( ),Get_Volume( )
Ambient Lighting Control
Status LED Control
Regulation of BDU (temperature, pressure, etc.)


Get_User_Info( )
Data Acquisition


Send_Drink_Request( ), Wait_For_State( )
Set_Temp( ), Set_Pressure( )
Drink Delivery

Dispense_Drink( ), Monitor_Flow( )
OBSTACLES WITH DISPENSING UNIT

Pressure Determination
 Analog
 How

 Dual
Pressure Gauges
to Convert this to a Digital Signal
Calculations Using System State?
Gauge System
 Difficulty

Flow Meters Effect on Beverage
 Slow

in Keeping Accurate Measurements
Pours, Foamy Dispensing
We are Electrical Engineers, not Mech E’s
WIRELESS CONTROL UNIT
External Flash
WIRELESS CONTROL UNIT (WCU)


Custom PCB
Microcontroller


4 wire Resistive Touch Panel





ADC outputs
External Flash/EEPROM
Wireless Module – Nordic/ZigBEE
3-Track Card Reader – Serial
Battery Powered



High Speed for LCD
Switch-Mode Power Supply (SMPS)
Battery Monitoring IC
Additional Buttons for Initial design and debug
WCU USER INTERFACE

Graphic LCD – 3.5”
 18
bit Parallel/SPI
 320X240 RGB

Built in LCD Controller
 172Kbytes
Internal RAM
Integrated Touch Screen
 Low Power

WIRELESS COMMUNICATION
RF Design…no thanks (Time, $, Skills, Tools)
 nRF24L01 - 2.4GHz Transceiver IC

Cheap $8
 13.5mA/11.3mA peak RX/TX current
 900nA powered down
 2Mbps
 Protocol Stack already written
 10Mbps SPI interface
w/ interrupt

SOFTWARE AND FIRMWARE (WCU)

LCD Display


Touchscreen


Set_New_Temp( ), Set_New_Pressure( )
Database Access


Get_User_Info( )
Wireless Control


Get_Touch_Input( )
3-Track Reader


Refresh_Display( ), Highlight_Selection( )
New_User( ), Add_Drink( ), Remove_Drink( ), Check_User( ),
Block_User( )
Power

Check_Battery_State( )
FLOW DIAGRAM (WCU)
System
Displays
State
(Idle)
User makes Yes
Selection?
WCU
Highlights
Selection
No
WCU
Updates
Screen
WCU
Receives
System
Data
Database
Query?
No
Yes
WCU
Accesses
Database
Send or
Receive
Data
COMPUTER MODULE (CM)
COMPUTER MODULE

Wireless Module
Communicate w/ BDU and Wireless Control Unit
 Serial connection w/ PC


Database Window


Contains all valid customer ID’s
User Interface
Display statistics and system status
 Ability to control system

 Pressure,

Temperature
Internet Status Display
DELEGATION OF WORK
Task
Person Responsible
Wireless Control Unit ft. Touchscreen
Riley
Wireless Communication
Riley
MySQL Database
Riley
Pressure Transducers
Riley
Magnetic Card Reader
Riley
Flow Sensors
Riley
Temperature Sensors
Riley
Board Design
Riley
GUI design
Riley
DELEGATION OF WORK
Task
Person Responsible
Wireless Control Unit ft. Touchscreen
Alex & Mike
Wireless Communication
Bryan
Database Programming
Justin
Pressure Transducers
Bryan & Mike
Magnetic Card Reader
Justin
Flow Sensors
Alex & Justin
Temperature Sensors
Mike
Board Design
Alex
GUI design
Bryan
DELIVERABLES
Milestone 1
3.16.2010
BDU built, BDU
PCB rev 1,
BDU Board
tested w/
functioning
sensors
BDU functional
w/ wireless
comm.
All systems
tested and
working
LCD SW
development, UI
designed
LCD interface
functional, WCU
PCB rev 1,
Functional LCD
interface w/
wireless comm.
Documentation
Initial Database
set up
Wireless comm.
development
Computer
Module
Complete
Zero all nighters
in the last week
SUPPLEMENTARY FEATURES
Ambient Mood Lighting
 User Interaction on BDU

 LCD/Graphic
LCD (Nokia 6100)
Charging WCU
 Internet module for remote access to database

RISKS AND MITIGATIONS
LCD/ touchscreen
incomplete
Wireless comm.
incomplete
Difficulties w/ flow
sensing & control
PCB design and/or
population mistakes
Pressure Sensor
Failure
•Switch to smaller, simpler screen or a non-Graphic
LCD
•Implement control system on personal computer
using wired connection (serial)
•Measure volume using force sensors
•Fix mistakes and order another rev if there is time
•Cut traces and hand solder wires
•Approximate pressure using system variables
BUDGET
Item
PCB’s (3 boards, 1-2 revs)
Price
$200.00
Graphic LCD w/ touchscreen
$30.00
General Components
$50.00
Card Reader (2)
$30.00
Force Sensor (2)
$50.00
Flow Meter
$50.00
Temp Sensor
$10.00
Pressure Sensors
$50.00
Kegerator (system)
$150.00
nRF24L01 Wireless transceiver (3 modules)
$25.00
Misc. (Shipping etc.)
$100.00
Total
$745.00
QUESTIONS???