Robotics 1.0 Lesson Plan
Lesson 15: Plant Detective

Purpose: To help students use moisture and photoresistor sensors with Crickit to monitor environmental conditions for plant growth.

No. of. Classes

1 - (Time: 1 hour and 30 minutes; maximum of 4 children per group).

Materials Required

Laptop or desktop with Mu Editor installed.

CircuitPython installed on the CPX board.

Circuit Playground Express (CPX) board with USB cable.

Crickit

Photoresistor sensor.

Moisture sensor.

Jumper wires.

Curriculum Content 5.1 Introduction to Crickit
6.5 Moisture Sensor
6.8 Photoresistor (external)
Prior knowledge

Students should know how to connect Crickit with the CPX and connect external sensors to Crickit.

Exercises

Exercise:1


Connect a moisture sensor and a light sensor to the Crickit board and read its values.


Moisture sensor LDR Sensor

  • View the Connection part of the moisture sensor and photoresistor sensor with the CPX here.


  • Read the value of moisture sensor and light sensor using the instructions in this document


  • Implement this pseudocode to read the environmental conditions for plant growth

    • Solution


  • Click here to see the solution video for Exercise 1
  • Click here to see the solution document for Exercise 1
    • Teacher's Instruction
    1. Go around and check if children are facing any troubleshooting issues, and help them solve them.
    2. Click here to know more about photoresistor working.
    3. Click here to know more about moisture sensor working.
    4. Ask why we need to check sensor values continuously.
    5. Discuss how this can be used in real life (greenhouse, smart garden, etc.).
    6. Ask students to unplug and carefully remove the wires.
    7. Discuss with students why we need external sensors and why we do not use the light sensor on the CPX.
    8. Explain about different variants of light sensor (digital, analog) and teach them to adjust the sensitivity of the sensor using the potentiometer on the sensor
    9. How do you think a photoresistor or a moisture sensor converts changes in light or soil moisture into electrical signals that a controller like the CPX can understand?