Download - Growing Food With Open Source (Sarah Sharp)
Growing Foodwith Open Source
OSCON 2011Sarah Sharp@sarahsharp
Hello!
✔ Linux Kernel hacker
✔ Gardener
I'm still a lazy hacker
github.com/sarahsharp/GardenGeek
Problem #1: Scheduling
Garden Calendar tool
● 904 lines of C● Object oriented representation of plants● Takes a CSV file for input
● 11 magic fields● not all are required
oregon spring tomatoes,1,7,3,2010-04-13,0,75,.80,6,14,0
Garden Calendar tool: Phase I
● Started Feb 21, 2010● Plain text output on Mar 7, 2010
Issues with Phase I
● Worked pretty well● Seed germination
rates are optimistic!● Often forgotten● No integration with
other calendaring tools
Garden Calendar tool: Phase II
● Goal: output iCalendar and integrate with google calendar.
● Issues: RFC 2445
Issues with Phase II
● Google calendar update lag● Really should be a todo list
● Integration with Remember The Milk?● Need an easy way to defer tasks
● Web front end?● Storage for users
Problem #2: Frost
How Frost Works
How Gardeners deal with frost
Dealing with Spring Weather:“Cold Snaps”
Data Source: WunderGround.com,Portland, Oregon, USA,
April 2010
Lazy Hacker: Polling vs. Interrupts
Search for the Perfect Android App
● Need an alert for frosts● Alert must be timely● Nice: open source app
Weather Checker
● Need an alert for frosts● Alert must be timely● Nice: open source app
Weather Checker
Search for the Perfect Android App
● Need an alert for frosts● Alert must be timely● Nice: open source app
Weather Checker● Alerts too often● Alerts at the wrong time● “average” temperature?
● Need an alert for frosts● Alert must be timely● Nice: open source app
Weather Checker● Alerts too often● Alerts at the wrong time● “average” temperature?
DIY
“You may not use the Wunderground Data Feed for use in a mobile
application for mass distribution, even if there is no monetary cost for the mobile
application.”
Open Government Data
● NOAA weather data● No history, only future predictions● Only for the United States● SOAP interface that returns XML
Garden Weather Alert
Garden Weather Alert TODO
● Add a background task for alerts● Alert on hail, wind, extreme heat● Use GPS coordinates● Support international locations● Options for °F vs. °C
Automatic Wateringwith Arduinos
Garduino: Gardening + Arduino
● Automatically waters your plants based on soil moisture
● Good tutorial on instructables.com
http://www.instructables.com/id/Garduino-Gardening-Arduino/
Soil Moisture Sensor
http://www.cheapvegetablegardener.com/2009/11/how-to-make-cheap-soil-moisture-sensor-2.html
Soil Moisture Sensor Science
V=I*R
R = infinite ohms I = 0 ampsV = 0 volts
R is finite I > 0 amps V > 0 volts
Garduino Step 1:Build Soil Moisture Sensors
Garduino Step 2:Hello Blinky LEDs
Garduino Step 2:Hello Blinky LEDs
Garduino Step 2:Hello Blinky LEDs
Garduino Step 3:Hello digital output
Garduino Step 4:Set up watering system
Garduino Step 4:Set up watering system
http://powerswitchtail.com/
Garduino Step 5:Calibrate System
● Soil moisture sensor takes a while to react● Need Arduino code to:
● Limit how often the pump runs● Don't water more often than N seconds
● Issues:● No RTC on the Arduino● Use milliseconds from start
● ~80 lines of code (with detailed comments)
Final Garduino
powertail
switch
wallpower
Arduino
soilmoisturesensor
GarduinoDemo
What's next?
● Wireless communication● JeeNodes - $22 kit
● Finish irrigation system
Want get involved?
● http://www.gardengeek.org● http://github.org/sarahsharp/GardenGeek● Twitter/Identica: @gardengeekery
Thank you!
