FAILURE TO INITIATE AND FOLLOW YOUR OWN SAFETY PROCEDURES MAY RESULT IN BODILY INJURY OR DEATH!

Transcription

1 Potted Plant Protector PART NO Build a digital guardian for your favorite plants! Using an Arduino and a few inexpensive sensors, you can keep your plants extremely happy with the proper amount of moisture, warmth, and light. The simplest version of Potted Plant Protector senses the brightness of the light, wetness of the soil, and warmth of the air that your plant is exposed to. It outputs these readings over USB, displaying on your computer screen. WARNING: If you are unsure of the dangers involved with your particular project, consult with someone who is experienced. Always wear eye protection and gloves. FAILURE TO INITIATE AND FOLLOW YOUR OWN SAFETY PROCEDURES MAY RESULT IN BODILY INJURY OR DEATH! Time Required: 1 day depending on experience Experience Level: Advanced Required tools and parts: Wire cutter / stripper Computer running Arduino IDE software Soldering iron and solder USB cable Bill of Materials: Qty Jameco SKU Component Name Arduino Uno Surface Mount (Revision 3) Cell 1 Alkaline Manganese Dioxide 9V 2-Pin Point Solderless Breadboard Resistor Carbon Film 10k Ohm 1/4 Watt 5% Wire Jumper Reinforced 300 Volt 24 AWG Thermistor PTC 100 Ohm 2 Pin Photocell 250mw 250V Peak 12K Ohm Max Light 1M Ohm MIN Dark Pin 10mm Diffused RGB LED - Common Anode Resistor Carbon Film 330 Ohm 1/4 Watt 5% Display LCD 16X2 Serial Potentiometer 10K Rv24A-10-15R1-B10K Linear Taper 1/2 Watt.335" /8" PHILLIPS PAN HEAD SCREW Nuts Hex 0.125in Steel Zinc 8-32 Step 1 - Basic build: Light, heat, and moisture sensing In a scrap of plastic, drill 2 holes 1/2" to fit your bolts. Make a second spacer and thread your bolts through both spacers, to keep them separated at a distance that won't vary.

2 Step 2 - Build the 3-sensor circuit. Here we'll use this setup for our 3 sensors "soil moisture, temperature, and light" and put them all together to create the circuit shown in the second schematic. Following the schematic, build the circuit on the breadboard as shown in the third photo. The thermistor and photoresistor are on the breadboard; the soil probe is just 2 long wires, each wrapped around a bolt and secured with a nut. The soil probe is connected to the Arduino's analog pin A0, the thermistor to pin A1, and the photoresistor to pin A2. Step 3 - Program the Arduino. To read the 3 sensors, we simply repeat this code for all 3 sensors, add variable declarations, and set up our serial port. Open THE CODE in the Arduino IDE, and upload it to your Arduino. //initialize variables for sensor pins int moistpin = 0; int temppin = 1; int lightpin = 2; //initialize variables to store readings from sensors int moistval = 0; int tempval = 0; int lightval = 0;

3 void setup() //initialize the serial port Serial.begin(9600); void loop() //read values from the sensors moistval = analogread(moistpin); tempval = analogread(temppin); lightval = analogread(lightpin); //display the readings on the serial monitor in a coherent way Serial.print("moisture reads "); Serial.println(moistVal); Serial.print("temperature reads "); Serial.println(tempVal); Serial.print("light reads "); Serial.println(lightVal); //wait one second before continuing. We're doing this so that we don't just see readings fly by the screen delay(1000); Step 4 - Place and calibrate sensors. In open air: both sensors read 0 Very dry soil: 2% Vegetronix, 5 DIY Slightly moist: 7%, 150 Slightly moister: 8%, 250 Wet soil: 28%, 370 Very wet soil: 51%, 385 Probe immersed in water: 85%, 480 So if I want to water my soil to about 28% moisture, I should watch for a sensor reading of about 385 as my cutoff point.

4 Step 5 - Intermediate build: Add an RGB LED indicator. Generally, you can connect an LED to an Arduino with the circuit shown in the first diagram here. On the schematic symbol for an LED, the triangle points to the anode (negative side). On an actual LED, the longer lead is the one youâ ll connect to ground. The resistor regulates current to the LED: too much current, and our LED will burn out after a couple of seconds rather than lasting the 10,000-odd hours that it should. Step 6 - Connect the LED into your circuit. Following the schematic, connect the LED to +5V power and to the Arduino's digital input/output (I/O) pins D9, D10, and D11.

5 Step 7 - Reprogram the Arduino. code:::: //initialize variables for sensor pins int moistpin = 0; int temppin = 1; int lightpin = 2; //initialize variables to store readings from sensors int moistval = 0; int tempval = 0; int lightval = 0; //initialize variables for LED pins int redpin = 11; int greenpin = 10; int bluepin = 9; void setup() //initialize the serial port Serial.begin(9600); //set LED pins to output mode pinmode(redpin, OUTPUT); pinmode(greenpin, OUTPUT); pinmode(bluepin, OUTPUT); //set LED pins to off digitalwrite(greenpin, digitalwrite(bluepin, void loop() //read values from the sensors moistval = analogread(moistpin); tempval = analogread(temppin); lightval = analogread(lightpin); //display the readings on the serial monitor in a coherent way Serial.print("moisture reads "); Serial.println(moistVal); Serial.print("temperature reads "); Serial.println(tempVal); Serial.print("light reads "); Serial.println(lightVal); //wait one second before continuing. We're doing this so that we don't just see readings fly by the screen delay(1000); //turn on LED to blue, others off if moisture pins are touching together if (moistval > 1000) blue(); //wait one second delay(1000); if (tempval > 148) red();

6 //wait one second delay(1000); //turn on green if light sensor reads 600 or brighter if (lightval > 600) green(); //wait one second delay(1000); void blue() digitalwrite(greenpin, digitalwrite(bluepin, LOW); void red() digitalwrite(redpin, LOW); digitalwrite(greenpin, digitalwrite(bluepin, void green() digitalwrite(greenpin, LOW); digitalwrite(bluepin, void off() digitalwrite(greenpin, digitalwrite(bluepin, void on() digitalwrite(redpin, LOW); digitalwrite(greenpin, LOW); digitalwrite(bluepin, LOW); This will cycle our LED through its different colors over the course of 5 seconds, depending on our plant's conditions:

7 The LED will flash blue for 1 second if the soil is moist. The LED will flash red if our plants are warm. The LED will flash green if our plants are getting sun. Step 8 - Advanced: Display readings on an LCD screen. You'll need to do some soldering to wire up the LCD screen. It's easy if you use good tools and proper technique. Step 9 - Connect the LCD display and test it. Following the schematic, connect the LCD into your circuit: LCD pin #1 to Ground on your breadboard LCD pin #2 to 5V and also the potentiometer outer pin --does not matter which outer pin, just pick one. LCD pin #3 to the potentiometer wiper --that is the middle pin. LCD pin #4 to the Arduino digital pin #7 --this is different from the stock LCD Library. LCD pin #5 to GND and also the potentiometer's other outer pin. LCD pin #6 to the Arduino digital pin #6 --this is different from the stock LCD Library. LCD pins #7 - #10 do not connect to anything. LCD pin #11 to the Arduino digital pin #5 LCD pin #12 to the Arduino digital pin #4 LCD pin #13 to the Arduino digital pin #3 LCD pin #14 to the Arduino digital pin #2 LCD pins #14 and #15 do not connect to anything. To test your LCD, here's their sample code, adapted for our pins. #include // initialize the library with the numbers of the interface pins LiquidCrystal lcd(7, 6, 5, 4, 3, 2);

8 void setup() // set up the LCD's number of columns and rows: lcd.begin(16, 2); // Print a message to the LCD. lcd.print("hello, world!"); void loop() // Turn off the display: lcd.nodisplay(); delay(500); // Turn on the display: lcd.display(); delay(500); Turn the potentiometer until you can see "hello world" displayed on the screen. If your LCD is connected correctly, this should blink on and off every second. Step 10 - Reprogram the Arduino. /* // Potted Plant Protector using sensors // By Dibyajyoti Das // With thanks to */ //potted plant protector with rgb indicator LED and LCD //with thanks to // Include the LCD Library #include //initialize variables for sensor pins int moistpin = 0; int temppin = 1; int lightpin = 2; //initialize variables to store readings from sensors int moistval = 0; int tempval = 0; int lightval = 0; //initialize variables for LED pins int redpin = 11; int greenpin = 10; int bluepin = 9;

9 // initialize the library with the numbers of the interface pins LiquidCrystal lcd(7, 6, 5, 4, 3, 2); void setup() //initialize the serial port Serial.begin(9600); //set LED pins to output mode pinmode(redpin, OUTPUT); pinmode(greenpin, OUTPUT); pinmode(bluepin, OUTPUT); //set LED pins to off digitalwrite(greenpin, digitalwrite(bluepin, // set up the LCD's number of columns and rows: lcd.begin(16, 2); void loop() moistval = analogread(moistpin); //display moisture reading on lcd lcd.clear(); lcd.print("moisture "); lcd.print(moistval); //turn on LED to blue, others off if moisture pins are touching together if (moistval > 1000) blue(); //wait 4 seconds delay(4000); //display moisture reading on lcd tempval = analogread(temppin); lcd.clear(); lcd.print("temperature "); lcd.print(tempval); if (tempval > 148) red(); delay(4000); lightval = analogread(lightpin); //display moisture reading on lcd lcd.clear(); lcd.print("light "); lcd.print(lightval);

10 //turn on green if light sensor reads 600 or brighter if (lightval > 600) green(); delay(4000); void blue() digitalwrite(greenpin, digitalwrite(bluepin, LOW); void red() digitalwrite(redpin, LOW); digitalwrite(greenpin, digitalwrite(bluepin, void green() digitalwrite(greenpin, LOW); digitalwrite(bluepin, void off() digitalwrite(greenpin, digitalwrite(bluepin, void on() digitalwrite(redpin, LOW); digitalwrite(greenpin, LOW); digitalwrite(bluepin, LOW);

11 Step 11 - Growing further We will soon add controls, power management, solar power, connectivity, better sensors.