Making My Plant Scream at Me When It Needs Watering.

Using some sensors, I took the real-time readings from the plant to trigger a sound file through SonicPi.

Real-time readings from the sensors are received and compared to check whether they are below the critical levels, and if yes, the Arduino sends out a MIDI note: an F# note for sub-critical levels (when the plant needs watering) and a Bb note when the moisture level rises abruptly ( when the plant is watered).

The MIDI note then goes through a virtual port and a serial bridge.

SonicPi listens to the incoming note on the virtual port and compares whether the incoming note is F# or Bb.

If the former, it triggers a sound file, and if the latter, another sound file.

All in all, the plant is putting up a musical performance of just two notes.

Supplies

1. Moisture sensor.
2. Humidity sensor (optional).
3. Arduino Uno.
4. Bluetooth Speaker.
5. Breadboard.
6. LoopMidi.
7. HairlessMidi serial bridge.
8. SonicPi.

Step 1: Connect the Sensors

The connection is rather simple and could be done in a jiffy.

Step 2: Write the Arduino Code

int sensor_pin = A0;

int output_value_new ;

int output_value_old = 0;

int satisfied_note = 0x6A;

int scream_note = 0x66;

int threshold_moisture = 80;

void setup() {

  Serial.begin(9600);

  Serial.println("Reading From the Sensor ...");

  delay(2000);

  }

void loop() {

  output_value_new= analogRead(sensor_pin);

  output_value_new = map(output_value_new,550,0,0,100);

  if (output_value_old ==0){

  output_value_old = output_value_new;

  }

  if (output_value_new <= threshold_moisture) {

   //Note on channel 1 (0x90), some note value (note), silent velocity (0x00):

   noteOn(0x90, scream_note, 0x7F);

   delay(100);

  }

  int output_difference = output_value_new - output_value_old;

  if (output_difference >=30){

  //Note on channel 1 (0x90), some note value (note), middle velocity (0x45):

  noteOn(0x90, satisfied_note, 0x7F);

  delay(100);

  }

  Serial.print("Mositure : ");

  Serial.print(output_value_new);

  Serial.println("%");

  delay(1000);

  output_value_old = output_value_new;

}

void noteOn(int cmd, int pitch, int velocity) {

 Serial.write(cmd);

 Serial.write(pitch);

 Serial.write(velocity);

}

Step 3: Write the SonicPi Sketch

screams = "YOUR_SMAPLE_FOLDER_HERE"

satisfied = "YOUR_SMAPLE_FOLDER_HERE"

live_loop :midi_piano do

 use_real_time

 note, velocity = sync "/midi:loopmidi_port_0:1/note_on"  

 if note == 102 #Fsharp7

  sample screams, rrand_i(1,7)

  sleep(rrand_i(1,5))

 end

 if note == 106 #Bb7

  sample satisfied, rrand_i(1,3)

  sleep(rrand_i(1,4))

 end

end

in_thread do

 use_real_time

 use_real_time

 note, velocity = sync "/midi:loopmidi_port_0:1/note_on"

 if note == 106 #Fsharp7

  sample screams, rrand_i(1,7)

  sleep(rrand_i(2,6))

 end

 if note == 102 #Bb7

  sample satisfied, rrand_i(1,3)

  sleep(rrand_i(1,4))

 end

end

Step 4: The Final Project

I have made the demonstration video along the lines of those sleazy TV infomercial ads we used to see in the days of yore.