MediumOne Cloud ESP8266 Tutorial: Plant Care System (Part I Hardware)
Build an automated cloud controlled system to water the plant and turn on the artificial light for the plant when needed. The hardware has a moisture sensor and a light level sensor to provide the critical data for the system to decide when the plant needs to be watered or given light when it is dark.
Also, temperature and humidity readings are available for the system to evaluate the environment factors for the plant. If the temperature is very high, it can be used to increase the watering duration or alert users in case some sensitive plants cannot tolerate extreme temperatures.
Diagram 1: The complete view of the system board and the plant. The heart of the electron system is ESP8266 processor which has integrated WiFi to communicate to the MediumOne cloud.
Video 1: When the soil moisture level is low (dry), the MediumOne cloud Python code enables the Water pump to transfer water from the water tank to the plant.
Video 2: Based on the reading of the light sensor, the MediumOne cloud Python code turn on or off the artificial light lamp.
Diagram 2: The soil moisture is buried in the soil and can detect moisture in the soil 5 cm deep below the surface.
Diagram 3: The light (photo-resistor) senor (bottom) and the temperature and humidity sensor are shown.
Diagram 4: The ultrasonic senor measures how much water remains in the water tank before it alerts the system of low water lever warning and stop the water pump from drawing water. The floating Styrofoam aids the senor take accurate measurement.
Diagram 5: The water pump sits on the bottom with a tube attached for drawing water from the water tank.
Diagram 6: The OLED display shows the value of the measurements as well as the status of the lamp and water pump.
Diagram 7: The AC relay module provides 2 channels to control the lamp and water pump independently. (For safety concern with AC side, use insulator and heat shrink to cover the bare wires. Alternatively use two AC/DC Control Relays from Digital Loggers)
Full Board Overview:
Diagram 8: All the component's label is added.
1. An Adafruit Huzziah Esp8266. (Adafruit)
2. A 4 channel AC Relay with plastic case. (Alternatively use two AC/DC Control Relays from Digital Loggers) (Amazon)
3. A 128 x 64 OLED I2C display. (Amazon)
4. An analog to digital converter with I2C interface. (Adafruit)
5. A ultraonic sensor. (Amazon)
6. A soil moisture sensor. (Amazon)
7. A photo resistor sensor. (Amazon)
8. A temperature and humidity sensor with I2C interface. (Seeed)
9. A 4 watt water pump with 2" plastic tubing. (Local fish store)
10. 8 Resistors(100K, 4.7k, 1M ohm), 6 NPN transistor, 1 PNP transitors and 1 NFET transistor (see schematic diagram.) (Any electronic store)
11. A plastic water tank. (Walmart or Dollar store)
12. A plant.
13. A 5 Volt AC to DC adapter. (Fry's Electronic store)
14. Two power cords (modified to connect between the relay and the lamp/water pump) (Fry's Electronic store)
Diagram 9: Breadboard Diagram
Diagram 10: Schematic Diagram