Final Presentation November 29, 2011

Team Members Duties: Real Time Clock Website Kevin Wellman Electrical Engineering Reginald Lott Adam Teague Matthew Adkins Duties: Power Circuit PCB Design Duties: User Interface Microprocessor Programming Duties: Sensors PCB Design Dr. Winton Faculty Advisor

Overview Problem Solution System Overview Constraints Technical Practical Improvements PCB Enclosure Final Product Testing Production Cost References Questions

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] Competing Products Cyber Rain XCI Requires internet access Weather reports cover general area $499 MSRP

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 $175

System Overview Microcontroller Moisture Sensor Temperature Sensor Power Supply Sprinkler Interface Real Time Clock

Physical Model

Technical Constraints Name Description Moisture Sensor Range The WCSC must be able to sense the volumetric water content of the soil from 20 to 50 percent. Outputs The WCSC must be able to output 24 V AC at 0.6A. Display 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 20 to 50 degrees Fahrenheit. Voltage The WCSC must operate from a standard 120V wall outlet.

Practical Constraints TypeConstraintDescription EnvironmentalDurabilityThe device must be able to operate in harsh conditions. UsabilityCustomer Convenience The device must be easy to use and change watering schedule.

Improvements From Design 1 RTC from breakout board to through hole mountable components AC/DC converter resized from 12VDC to 6VDC Implementation of PCB from Breadboard

PCB

Enclosure NEMA 4 / IP65 Case with Clear Cover Dimensions of 7” x 6” x 3”

Final Product

Systems Test Test were conducted on the following components in this order after the arrival of the PCB: PCB Power supply Microprocessor LCD RTC Temperature Sensor Moisture Sensors Enclosure Entire System

Temperature Probe Test Data Ambient temp measured using a Fluke 189 temp probe and compared to LM 60 measurements.

Test Preparations Soil Preparation Bake at 225°F for 24 hours as per manufacturer recommendations Sample size of 16oz of dirt for each zone Test were performed in increments of VWC

Moisture Sensor Test Data

Testing of Entire System Moisture (VWC) Current Moisture (VWC) Test 1 Moisture content greater than Moisture Setting Temperature greater than Temperature Setting Sprinkler should not operate Test 2 Moisture content less than Moisture Setting Temperature less than Temperature Setting Sprinkler should not operate Test 3 Moisture content less than Moisture Setting Temperature greater than Temperature Setting Sprinkler should operate

Operation and Testing

Production Cost Part #DescriptionQuantityPrice per UnitPrice per Unit for 100 VG 400Vegetronix Moisture Sensor PIC24HJ32GP202-I/SO-NDMicroprocessor LM60CIZ-NDTemperature Sensor LM2940CT-5.0-ND5V Regulator LM2937ET-3.3-ND3.3V Regulator F3167TR-ND1/2A Fuse10.29 EG4788-NDPush Button MOC3011M-NDOpto-coupler Triac Out NDLED NDTRIAC 600V 1A TO Y L-NDPotentiometer 10K CFAH2402A-YYH-JTLCD BEN-80PCBLKEnclosure A-20-24B28-ND120/24V Transformer BP5063-5AC/DC Converter 5V 200mA Pushbutton Switches DS1307+-NDRTC SER3302-NDCrystal P2.4KBACT-ND24 Ohm Resisitor P91BACT-ND910 Ohm Resistor P220KBACT-ND2.2K Ohm Resistor P4.3BACT-ND4.3K Ohm Resistor P2.2MBACT-ND2.2M Ohm Resistor ND10pF Capacitor ND0.1uF Capacitor CustomPCB Total Cost of Parts for 1 Unit

References: [1] Sprinkler Warehouse. [Online]. Available: Soil-Moisture-Sensors-s/7666.htm. [Accessed: January 18, 2011]. Soil-Moisture-Sensors-s/7666.htm [2] Beanworthy. [Online]. Available: 16Zone-Automated-Sprinkler-Controller/A/B000ZHTXEC.htm. [Accessed: January 18, 2011]. 16Zone-Automated-Sprinkler-Controller/A/B000ZHTXEC.htm [3] “VG400 Moisture Probe” [Online] Available:

Any Questions?