Transcript Digital Shower Controller

DIGITAL SHOWER CONTROLLER
BY
NATHAN GARNER
KASUN KUMARAGE
CONTENTS
•
GOALS
•
INITIAL DESIGN
•
TECHNICAL DESCRIPTION
•
BLOCK DIAGRAM
•
OVERALL CIRCUIT DIAGRAM
•
POWER REGULATOR
•
COMPONENTS
•
SOFTWARE FLOW CHART
•
COST
•
FUTURE IMPROVEMENTS
•
CONCLUSIONS
•
FUTURE CONSIDERATIONS
GOALS
• TAKE USER INPUT TO CONTROL THE TEMPERATURE OF A SHOWER
• OFFER CONVENIENCES TO THE USER THAT CONVENTIONAL SYSTEMS CANNOT
• AUTOMATICALLY AND ACCURATELY MAINTAIN DESIRED TEMPERATURE
• FOUR PROGRAMMABLE PRESET BUTTONS
• ALLOW FOR USER TO ADJUST DESIRED TEMPERATURE DEPENDING ON DAILY PREFERENCE
INITIAL DESIGN
• ARDUINO UNO
• PIN EXPANSION
• ELECTRONIC FLOW CONTROL VALVES
• CAPACITIVE TOUCH SCREEN
• DIAL INPUT TO ADJUST TEMPERATURE
TECHNICAL DESCRIPTION
• User Interface
• Takes user input
• Gets readings from temperature sensors
• Tells servo which direction to turn
depending on current temperature
reading and desired temperature
reading
• Temperature Sensors
• One on each water output to read
temperatures
• Servo Motor
• Turns the rough in valve to control the
hot/cold water mixture
• Solenoid Valve
• Normally closed
• Opens when user selects bath
Temperature
Sensor
User
Interface
Servo
Motor
Temperature
Sensor
Solenoid
Valve
BLOCK DIAGRAM
Sensors
Solenoid
Valve
Servo
Motor
Microprocessor
Push Buttons
LCD Screeen
OVERALL CIRCUIT DIAGRAM
• ELECTRICAL CIRCUIT SCHEMATIC
• VOLTAGE REGULATOR
• DARLINGTON PAIR TRANSISTOR TO CONTROL
SOLENOID VALVE
POWER REGULATOR
• WE USED THE LM7805 VOLTAGE REGULATOR
• 12V 2A REGULATED INPUT SUPPLY
• 5V OUTPUT VOLTAGE
• TWO CAPACITORS AT THE INPUT AND
OUTPUT OF THE LM7805
• REDUCES NOISE INTO AND OUT OF LM7805
• INCREASES EFFICIENCY OF VOLTAGE
REGULATOR
COMPONENTS
• SAINSMART MEGA2560
• ATMEGA2560 MICROPROCESSOR
• 5V SUPPLY VOLTAGE
• 54 DIGITAL I/O PINS
• 16 ANALOG PINS
• 16MHZ
COMPONENTS
• LCD SCREEN
• 2X16 CHARACTER DISPLAY
• RGB BACKLIGHT
• CONTRAST CONTROLLED BY PWM
COMPONENTS
• WATERPROOF TEMPERATURE SENSOR
(DS18B20)
• ±0.5°C ACCURACY
• -55°C TO 125°C RANGE
• DALLAS SEMICONDUCTORS 1 WIRE
INTERFACE
• SIMILAR TO I2C
• SLOWER BUT LONGER RANGE
COMPONENTS
• DIGITAL SERVO MOTOR
•
•
•
•
WATERPROOF
5V INPUT
125 OZ-IN TORQUE (0.651 LB-FT)
140 DEGREES RANGE
• SOLENOID VALVE
•
•
•
•
NORMALLY CLOSED
12V
2W
CONTROLLED BY TIP 120
SOFTWARE FLOW CHART
Power button
HW interrupt
Tub/Shower
interrupt
Tub or Shower
Get data from
Shower shower temperature
sensor
Set solenoid for
shower
Start
Tub
Get data from Tub
temperature sensor
Set solenoid for Tub
Toggle power state
Pwr state = ON
NO
Display
temparature
Display message to
user.
Turn the servo to
close the valve
Check for preset
status
Delay
No
YES
Pres and hold
Initialize sensors, LCD and
memory for presets.
Update button press status
Yes
Store the
temperature value
to the memory
location
Check if the
temperatures
with in the
tolerance
No
Preset temp <
actual
(need colder)
NO(Needs warmer water)
No
Up button
pressed
Yes
Open the valve by
turning the servo
CW
Yes
Close the valve by
turning the servo
CCW
No
Down button
pressed
Delay
Delay
Adjust servo to open
the valve
Yes
Adjust servo to close
the valve
COST
Parts
Cost
Sainsmart Mega
12.70
LCD Screen
14.95
Temperature Sensors
19.90
Push Buttons
4.00
Servo Motor
46.00
Solenoid Valve
19.00
Total
116.55
FUTURE IMPROVEMENTS
• ADD A TOUCH SCREEN GUI TO OUR DESIGN
• INTEGRATE SPEAKERS AND BLUETOOTH TO CONNECT TO WIRELESS DEVICES AND HOME
AUTOMATION SYSTEM
• REPLACE THE SERVO DRIVEN VALVE WITH AN ELECTRIC FLOW CONTROL VALVE
• WATERPROOF USER INTERFACE
CONCLUSIONS
• DESIGNED A SYSTEM THAT AUTOMATICALLY ADJUSTS TEMPERATURE
• SYSTEM CONTAIN FOUR PRESET BUTTONS
• TEMPERATURE CAN BE ADJUSTED AT ANY TIME DURING OPERATION
• MADE AN AFFORDABLE DESIGN
FUTURE CONSIDERATIONS
• DESIGN A CURRENT LIMITING CIRCUIT FOR OUR SOLENOID
• ADD HARDWARE DEBOUNCE CIRCUITS
• ADD A BACKUP BATTERY SYSTEM
ACKNOWLEDGEMENTS
• SPECIAL THANKS TO:
• STANISLAW LEGOWSKI
• JERRY HAMANN
• VICTOR BERSHINSKY
• GEORGE JANACK
• GALE BANDSMA
QUESTIONS?