Download Rechargeable Battery System (REBATEM)

Mid Semester Presentation
February 24, 2011
Team Members
Kevin Wellman
Adam Teague
Duties:
Duties:
Real Time Clock
Dr. Winton
Website
PCB Design
Electrical Engineering
Reginald Lott
Power Circuit
Electrical Engineering
Faculty Advisor
Matthew Adkins
Duties:
Duties:
User Interface
Sensors
Microprocessor
Programming
PCB Design
Electrical Engineering
Electrical Engineering
Overview:
 Problem
 Solution
 System Overview
 Constraints
 Technical
 Practical
 Approach
 Progress
Problem
 Current residential sprinkler systems are inadequate
in the following areas:
 Efficiency
 Ease of use
 Cost
Digital Sun S. Sense
Add-on device
Battery operated
(sensors and control unit)
$199 MSRP
[1]
Cyber Rain XCI
Requires internet access
Weather reports cover
general area
$499 MSRP
[2]
Solution
 Water Conserving Sprinkler Control
 Periodically monitors moisture content and
temperature
 Operates on user-defined schedule
 Requires no external devices for modifying settings
 Costs less than $150
System Overview
Moisture
Sensor
Temperature
Sensor
Microcontroller
Real Time
Clock
Power Supply
Sprinkler
Interface
Technical Constraints:
Name
Description
Moisture Sensor The WCSC must be able to sense the volumetric water content of the
Range
soil from 20 to 50 percent.
Outputs
Display
The WCSC must be able to output 24 V AC at 0.6A .
The WCSC display must provide relevant information and options to
the user, and it must be readable in well or dimly lit environments.
Technical Constraints (Cont.):
Name
Description
Temperature
Sensor Range
The WCSC must sense temperatures from 15 to 50 degrees
Fahrenheit.
Voltage
The WCSC must operate from a standard 120V wall outlet.
Practical Constraints
Type
Constraint
Description
Environmental
Durability
The device must be able to operate in
harsh conditions.
Usability
Customer
Convenience
The device must be easy to use and
change watering schedule.
Environmental
•Sensors must withstand a variety of
weather elements
• Heat
• Cold
• Water Resistant
•Control unit encasement durability
•Must be rugged enough to withstand incidental
impact
Usability
•The unit must be simple to configure
and operate.
• Water scheduling
• Time changes
• Display and Button Interface
Moisture Probe
Model
Power
Consumption
Prong Type
Price
VG400
< 800uA
single
$29.95
10mA
double
$91.95
EC-5
[3][4]
Component
Chosen
Power Control
Model
Solid State
Size in mm
Price
TRIAC
#568-3687-ND
Yes
4.2x4.8x5.2
$0.78
Relay
#306-1152-2-ND
No
10x5x5
$19.34
[5][6]
Component
Chosen
Power
Model
Ratio
Power
Rating
Price
Plug in
Transformer
120/24VAC
20VA
$16.18
On board
Transformer
120/24VAC
20VA
$13.78
[7][8]
Component
Chosen
Timeline
January
Research
Ordering
Parts
Design
Constructing
and test
Prototype
Working
Prototype
February
March
April
Progress
Progress
Pic uC
Progress
RTC
Progress
Temp
Progress
Opto-Coupler
TRIAC
Simulated
24v AC Load
References:
[1] Sprinkler Warehouse. [Online]. Available: http://www.sprinklerwarehouse.com/Ground-Soil-Moisture-Sensorss/7666.htm. [Accessed: January 18, 2011].
[2] Beanworthy. [Online]. Available: http://homegarden.beanworthy.com/CyberRain-XCI-16Zone-Automated-SprinklerController/A/B000ZHTXEC.htm. [Accessed: January 18, 2011].
[3] “VG400 Moisture Probe” [Online] Available: http://www.vegetronix.com/Products/VG400/.
[4] “EC-5” [Online]. Available: http://www.decagon.com/products/sensors/soil-moisture-sensors/ec-5-soil-moisture-smallarea-of-influence/
[5] “Triac" [Online] Available: http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=5683687+ND%09%09
[6] “Relay.” [Online] Available: http://parts.digikey.com/1/parts/1791165-relay-reed-hi-rf-bga-3-3v-spst-b10-03b.html
[7] “Plug in Transformer." [Online] Available: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=T1009ND.
[8] “On Board Transformer.” [Online] Available: http://parts.digikey.com/1/parts/999877-transf-lo-pro-dual-12vac-1-66apl20-24-130b.html
Any Questions?